kernel_optimize_test/kernel/locking/lockdep_proc.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
// SPDX-License-Identifier: GPL-2.0
/*
* kernel/lockdep_proc.c
*
* Runtime locking correctness validator
*
* Started by Ingo Molnar:
*
* Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
* Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
*
* Code for /proc/lockdep and /proc/lockdep_stats:
*
*/
#include <linux/export.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/kallsyms.h>
#include <linux/debug_locks.h>
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
#include <linux/vmalloc.h>
#include <linux/sort.h>
#include <linux/uaccess.h>
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
#include <asm/div64.h>
#include "lockdep_internals.h"
static void *l_next(struct seq_file *m, void *v, loff_t *pos)
{
return seq_list_next(v, &all_lock_classes, pos);
}
static void *l_start(struct seq_file *m, loff_t *pos)
{
return seq_list_start_head(&all_lock_classes, *pos);
}
static void l_stop(struct seq_file *m, void *v)
{
}
static void print_name(struct seq_file *m, struct lock_class *class)
{
char str[KSYM_NAME_LEN];
const char *name = class->name;
if (!name) {
name = __get_key_name(class->key, str);
seq_printf(m, "%s", name);
} else{
seq_printf(m, "%s", name);
if (class->name_version > 1)
seq_printf(m, "#%d", class->name_version);
if (class->subclass)
seq_printf(m, "/%d", class->subclass);
}
}
static int l_show(struct seq_file *m, void *v)
{
struct lock_class *class = list_entry(v, struct lock_class, lock_entry);
struct lock_list *entry;
char usage[LOCK_USAGE_CHARS];
if (v == &all_lock_classes) {
seq_printf(m, "all lock classes:\n");
return 0;
}
seq_printf(m, "%p", class->key);
#ifdef CONFIG_DEBUG_LOCKDEP
seq_printf(m, " OPS:%8ld", debug_class_ops_read(class));
#endif
#ifdef CONFIG_PROVE_LOCKING
seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class));
seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class));
#endif
get_usage_chars(class, usage);
seq_printf(m, " %s", usage);
seq_printf(m, ": ");
print_name(m, class);
seq_puts(m, "\n");
list_for_each_entry(entry, &class->locks_after, entry) {
if (entry->distance == 1) {
seq_printf(m, " -> [%p] ", entry->class->key);
print_name(m, entry->class);
seq_puts(m, "\n");
}
}
seq_puts(m, "\n");
return 0;
}
static const struct seq_operations lockdep_ops = {
.start = l_start,
.next = l_next,
.stop = l_stop,
.show = l_show,
};
#ifdef CONFIG_PROVE_LOCKING
static void *lc_start(struct seq_file *m, loff_t *pos)
{
if (*pos < 0)
return NULL;
if (*pos == 0)
return SEQ_START_TOKEN;
return lock_chains + (*pos - 1);
}
static void *lc_next(struct seq_file *m, void *v, loff_t *pos)
{
*pos = lockdep_next_lockchain(*pos - 1) + 1;
return lc_start(m, pos);
}
static void lc_stop(struct seq_file *m, void *v)
{
}
static int lc_show(struct seq_file *m, void *v)
{
struct lock_chain *chain = v;
struct lock_class *class;
int i;
static const char * const irq_strs[] = {
[0] = "0",
[LOCK_CHAIN_HARDIRQ_CONTEXT] = "hardirq",
[LOCK_CHAIN_SOFTIRQ_CONTEXT] = "softirq",
[LOCK_CHAIN_SOFTIRQ_CONTEXT|
LOCK_CHAIN_HARDIRQ_CONTEXT] = "hardirq|softirq",
};
if (v == SEQ_START_TOKEN) {
locking/lockdep: Reuse freed chain_hlocks entries Once a lock class is zapped, all the lock chains that include the zapped class are essentially useless. The lock_chain structure itself can be reused, but not the corresponding chain_hlocks[] entries. Over time, we will run out of chain_hlocks entries while there are still plenty of other lockdep array entries available. To fix this imbalance, we have to make chain_hlocks entries reusable just like the others. As the freed chain_hlocks entries are in blocks of various lengths. A simple bitmap like the one used in the other reusable lockdep arrays isn't applicable. Instead the chain_hlocks entries are put into bucketed lists (MAX_CHAIN_BUCKETS) of chain blocks. Bucket 0 is the variable size bucket which houses chain blocks of size larger than MAX_CHAIN_BUCKETS sorted in decreasing size order. Initially, the whole array is in one chain block (the primordial chain block) in bucket 0. The minimum size of a chain block is 2 chain_hlocks entries. That will be the minimum allocation size. In other word, allocation requests for one chain_hlocks entry will cause 2-entry block to be returned and hence 1 entry will be wasted. Allocation requests for the chain_hlocks are fulfilled first by looking for chain block of matching size. If not found, the first chain block from bucket[0] (the largest one) is split. That can cause hlock entries fragmentation and reduce allocation efficiency if a chain block of size > MAX_CHAIN_BUCKETS is ever zapped and put back to after the primordial chain block. So the MAX_CHAIN_BUCKETS must be large enough that this should seldom happen. By reusing the chain_hlocks entries, we are able to handle workloads that add and zap a lot of lock classes without the risk of running out of chain_hlocks entries as long as the total number of outstanding lock classes at any time remain within a reasonable limit. Two new tracking counters, nr_free_chain_hlocks & nr_large_chain_blocks, are added to track the total number of chain_hlocks entries in the free bucketed lists and the number of large chain blocks in buckets[0] respectively. The nr_free_chain_hlocks replaces nr_chain_hlocks. The nr_large_chain_blocks counter enables to see if we should increase the number of buckets (MAX_CHAIN_BUCKETS) available so as to avoid to avoid the fragmentation problem in bucket[0]. An internal nfsd test that ran for more than an hour and kept on loading and unloading kernel modules could cause the following message to be displayed. [ 4318.443670] BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low! The patched kernel was able to complete the test with a lot of free chain_hlocks entries to spare: # cat /proc/lockdep_stats : dependency chains: 18867 [max: 65536] dependency chain hlocks: 74926 [max: 327680] dependency chain hlocks lost: 0 : zapped classes: 1541 zapped lock chains: 56765 large chain blocks: 1 By changing MAX_CHAIN_BUCKETS to 3 and add a counter for the size of the largest chain block. The system still worked and We got the following lockdep_stats data: dependency chains: 18601 [max: 65536] dependency chain hlocks used: 73133 [max: 327680] dependency chain hlocks lost: 0 : zapped classes: 1541 zapped lock chains: 56702 large chain blocks: 45165 large chain block size: 20165 By running the test again, I was indeed able to cause chain_hlocks entries to get lost: dependency chain hlocks used: 74806 [max: 327680] dependency chain hlocks lost: 575 : large chain blocks: 48737 large chain block size: 7 Due to the fragmentation, it is possible that the "MAX_LOCKDEP_CHAIN_HLOCKS too low!" error can happen even if a lot of of chain_hlocks entries appear to be free. Fortunately, a MAX_CHAIN_BUCKETS value of 16 should be big enough that few variable sized chain blocks, other than the initial one, should ever be present in bucket 0. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200206152408.24165-7-longman@redhat.com
2020-02-06 23:24:08 +08:00
if (!nr_free_chain_hlocks)
seq_printf(m, "(buggered) ");
seq_printf(m, "all lock chains:\n");
return 0;
}
seq_printf(m, "irq_context: %s\n", irq_strs[chain->irq_context]);
for (i = 0; i < chain->depth; i++) {
class = lock_chain_get_class(chain, i);
if (!class->key)
continue;
seq_printf(m, "[%p] ", class->key);
print_name(m, class);
seq_puts(m, "\n");
}
seq_puts(m, "\n");
return 0;
}
static const struct seq_operations lockdep_chains_ops = {
.start = lc_start,
.next = lc_next,
.stop = lc_stop,
.show = lc_show,
};
#endif /* CONFIG_PROVE_LOCKING */
static void lockdep_stats_debug_show(struct seq_file *m)
{
#ifdef CONFIG_DEBUG_LOCKDEP
unsigned long long hi1 = debug_atomic_read(hardirqs_on_events),
hi2 = debug_atomic_read(hardirqs_off_events),
hr1 = debug_atomic_read(redundant_hardirqs_on),
hr2 = debug_atomic_read(redundant_hardirqs_off),
si1 = debug_atomic_read(softirqs_on_events),
si2 = debug_atomic_read(softirqs_off_events),
sr1 = debug_atomic_read(redundant_softirqs_on),
sr2 = debug_atomic_read(redundant_softirqs_off);
seq_printf(m, " chain lookup misses: %11llu\n",
debug_atomic_read(chain_lookup_misses));
seq_printf(m, " chain lookup hits: %11llu\n",
debug_atomic_read(chain_lookup_hits));
seq_printf(m, " cyclic checks: %11llu\n",
debug_atomic_read(nr_cyclic_checks));
locking/lockdep: Avoid creating redundant links Two boots + a make defconfig, the first didn't have the redundant bit in, the second did: lock-classes: 1168 1169 [max: 8191] direct dependencies: 7688 5812 [max: 32768] indirect dependencies: 25492 25937 all direct dependencies: 220113 217512 dependency chains: 9005 9008 [max: 65536] dependency chain hlocks: 34450 34366 [max: 327680] in-hardirq chains: 55 51 in-softirq chains: 371 378 in-process chains: 8579 8579 stack-trace entries: 108073 88474 [max: 524288] combined max dependencies: 178738560 169094640 max locking depth: 15 15 max bfs queue depth: 320 329 cyclic checks: 9123 9190 redundant checks: 5046 redundant links: 1828 find-mask forwards checks: 2564 2599 find-mask backwards checks: 39521 39789 So it saves nearly 2k links and a fair chunk of stack-trace entries, but as expected, makes no real difference on the indirect dependencies. At the same time, you see the max BFS depth increase, which is also expected, although it could easily be boot variance -- these numbers are not entirely stable between boots. The down side is that the cycles in the graph become larger and thus the reports harder to read. XXX: do we want this as a CONFIG variable, implied by LOCKDEP_SMALL? Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Nikolay Borisov <nborisov@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akpm@linux-foundation.org Cc: boqun.feng@gmail.com Cc: iamjoonsoo.kim@lge.com Cc: kernel-team@lge.com Cc: kirill@shutemov.name Cc: npiggin@gmail.com Cc: walken@google.com Link: http://lkml.kernel.org/r/20170303091338.GH6536@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-03 17:13:38 +08:00
seq_printf(m, " redundant checks: %11llu\n",
debug_atomic_read(nr_redundant_checks));
seq_printf(m, " redundant links: %11llu\n",
debug_atomic_read(nr_redundant));
seq_printf(m, " find-mask forwards checks: %11llu\n",
debug_atomic_read(nr_find_usage_forwards_checks));
seq_printf(m, " find-mask backwards checks: %11llu\n",
debug_atomic_read(nr_find_usage_backwards_checks));
seq_printf(m, " hardirq on events: %11llu\n", hi1);
seq_printf(m, " hardirq off events: %11llu\n", hi2);
seq_printf(m, " redundant hardirq ons: %11llu\n", hr1);
seq_printf(m, " redundant hardirq offs: %11llu\n", hr2);
seq_printf(m, " softirq on events: %11llu\n", si1);
seq_printf(m, " softirq off events: %11llu\n", si2);
seq_printf(m, " redundant softirq ons: %11llu\n", sr1);
seq_printf(m, " redundant softirq offs: %11llu\n", sr2);
#endif
}
static int lockdep_stats_show(struct seq_file *m, void *v)
{
unsigned long nr_unused = 0, nr_uncategorized = 0,
nr_irq_safe = 0, nr_irq_unsafe = 0,
nr_softirq_safe = 0, nr_softirq_unsafe = 0,
nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
sum_forward_deps = 0;
2019-07-09 18:15:22 +08:00
#ifdef CONFIG_PROVE_LOCKING
struct lock_class *class;
list_for_each_entry(class, &all_lock_classes, lock_entry) {
if (class->usage_mask == 0)
nr_unused++;
if (class->usage_mask == LOCKF_USED)
nr_uncategorized++;
if (class->usage_mask & LOCKF_USED_IN_IRQ)
nr_irq_safe++;
if (class->usage_mask & LOCKF_ENABLED_IRQ)
nr_irq_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
nr_softirq_safe++;
if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ)
nr_softirq_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
nr_hardirq_safe++;
if (class->usage_mask & LOCKF_ENABLED_HARDIRQ)
nr_hardirq_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
nr_irq_read_safe++;
if (class->usage_mask & LOCKF_ENABLED_IRQ_READ)
nr_irq_read_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
nr_softirq_read_safe++;
if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ_READ)
nr_softirq_read_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
nr_hardirq_read_safe++;
if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ)
nr_hardirq_read_unsafe++;
sum_forward_deps += lockdep_count_forward_deps(class);
}
#ifdef CONFIG_DEBUG_LOCKDEP
DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused);
2019-07-09 18:15:22 +08:00
#endif
#endif
seq_printf(m, " lock-classes: %11lu [max: %lu]\n",
nr_lock_classes, MAX_LOCKDEP_KEYS);
seq_printf(m, " direct dependencies: %11lu [max: %lu]\n",
nr_list_entries, MAX_LOCKDEP_ENTRIES);
seq_printf(m, " indirect dependencies: %11lu\n",
sum_forward_deps);
/*
* Total number of dependencies:
*
* All irq-safe locks may nest inside irq-unsafe locks,
* plus all the other known dependencies:
*/
seq_printf(m, " all direct dependencies: %11lu\n",
nr_irq_unsafe * nr_irq_safe +
nr_hardirq_unsafe * nr_hardirq_safe +
nr_list_entries);
#ifdef CONFIG_PROVE_LOCKING
seq_printf(m, " dependency chains: %11lu [max: %lu]\n",
lock_chain_count(), MAX_LOCKDEP_CHAINS);
locking/lockdep: Reuse freed chain_hlocks entries Once a lock class is zapped, all the lock chains that include the zapped class are essentially useless. The lock_chain structure itself can be reused, but not the corresponding chain_hlocks[] entries. Over time, we will run out of chain_hlocks entries while there are still plenty of other lockdep array entries available. To fix this imbalance, we have to make chain_hlocks entries reusable just like the others. As the freed chain_hlocks entries are in blocks of various lengths. A simple bitmap like the one used in the other reusable lockdep arrays isn't applicable. Instead the chain_hlocks entries are put into bucketed lists (MAX_CHAIN_BUCKETS) of chain blocks. Bucket 0 is the variable size bucket which houses chain blocks of size larger than MAX_CHAIN_BUCKETS sorted in decreasing size order. Initially, the whole array is in one chain block (the primordial chain block) in bucket 0. The minimum size of a chain block is 2 chain_hlocks entries. That will be the minimum allocation size. In other word, allocation requests for one chain_hlocks entry will cause 2-entry block to be returned and hence 1 entry will be wasted. Allocation requests for the chain_hlocks are fulfilled first by looking for chain block of matching size. If not found, the first chain block from bucket[0] (the largest one) is split. That can cause hlock entries fragmentation and reduce allocation efficiency if a chain block of size > MAX_CHAIN_BUCKETS is ever zapped and put back to after the primordial chain block. So the MAX_CHAIN_BUCKETS must be large enough that this should seldom happen. By reusing the chain_hlocks entries, we are able to handle workloads that add and zap a lot of lock classes without the risk of running out of chain_hlocks entries as long as the total number of outstanding lock classes at any time remain within a reasonable limit. Two new tracking counters, nr_free_chain_hlocks & nr_large_chain_blocks, are added to track the total number of chain_hlocks entries in the free bucketed lists and the number of large chain blocks in buckets[0] respectively. The nr_free_chain_hlocks replaces nr_chain_hlocks. The nr_large_chain_blocks counter enables to see if we should increase the number of buckets (MAX_CHAIN_BUCKETS) available so as to avoid to avoid the fragmentation problem in bucket[0]. An internal nfsd test that ran for more than an hour and kept on loading and unloading kernel modules could cause the following message to be displayed. [ 4318.443670] BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low! The patched kernel was able to complete the test with a lot of free chain_hlocks entries to spare: # cat /proc/lockdep_stats : dependency chains: 18867 [max: 65536] dependency chain hlocks: 74926 [max: 327680] dependency chain hlocks lost: 0 : zapped classes: 1541 zapped lock chains: 56765 large chain blocks: 1 By changing MAX_CHAIN_BUCKETS to 3 and add a counter for the size of the largest chain block. The system still worked and We got the following lockdep_stats data: dependency chains: 18601 [max: 65536] dependency chain hlocks used: 73133 [max: 327680] dependency chain hlocks lost: 0 : zapped classes: 1541 zapped lock chains: 56702 large chain blocks: 45165 large chain block size: 20165 By running the test again, I was indeed able to cause chain_hlocks entries to get lost: dependency chain hlocks used: 74806 [max: 327680] dependency chain hlocks lost: 575 : large chain blocks: 48737 large chain block size: 7 Due to the fragmentation, it is possible that the "MAX_LOCKDEP_CHAIN_HLOCKS too low!" error can happen even if a lot of of chain_hlocks entries appear to be free. Fortunately, a MAX_CHAIN_BUCKETS value of 16 should be big enough that few variable sized chain blocks, other than the initial one, should ever be present in bucket 0. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200206152408.24165-7-longman@redhat.com
2020-02-06 23:24:08 +08:00
seq_printf(m, " dependency chain hlocks used: %11lu [max: %lu]\n",
MAX_LOCKDEP_CHAIN_HLOCKS -
(nr_free_chain_hlocks + nr_lost_chain_hlocks),
MAX_LOCKDEP_CHAIN_HLOCKS);
seq_printf(m, " dependency chain hlocks lost: %11u\n",
nr_lost_chain_hlocks);
#endif
#ifdef CONFIG_TRACE_IRQFLAGS
seq_printf(m, " in-hardirq chains: %11u\n",
nr_hardirq_chains);
seq_printf(m, " in-softirq chains: %11u\n",
nr_softirq_chains);
#endif
seq_printf(m, " in-process chains: %11u\n",
nr_process_chains);
seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n",
nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
seq_printf(m, " number of stack traces: %11llu\n",
lockdep_stack_trace_count());
seq_printf(m, " number of stack hash chains: %11llu\n",
lockdep_stack_hash_count());
#endif
seq_printf(m, " combined max dependencies: %11u\n",
(nr_hardirq_chains + 1) *
(nr_softirq_chains + 1) *
(nr_process_chains + 1)
);
seq_printf(m, " hardirq-safe locks: %11lu\n",
nr_hardirq_safe);
seq_printf(m, " hardirq-unsafe locks: %11lu\n",
nr_hardirq_unsafe);
seq_printf(m, " softirq-safe locks: %11lu\n",
nr_softirq_safe);
seq_printf(m, " softirq-unsafe locks: %11lu\n",
nr_softirq_unsafe);
seq_printf(m, " irq-safe locks: %11lu\n",
nr_irq_safe);
seq_printf(m, " irq-unsafe locks: %11lu\n",
nr_irq_unsafe);
seq_printf(m, " hardirq-read-safe locks: %11lu\n",
nr_hardirq_read_safe);
seq_printf(m, " hardirq-read-unsafe locks: %11lu\n",
nr_hardirq_read_unsafe);
seq_printf(m, " softirq-read-safe locks: %11lu\n",
nr_softirq_read_safe);
seq_printf(m, " softirq-read-unsafe locks: %11lu\n",
nr_softirq_read_unsafe);
seq_printf(m, " irq-read-safe locks: %11lu\n",
nr_irq_read_safe);
seq_printf(m, " irq-read-unsafe locks: %11lu\n",
nr_irq_read_unsafe);
seq_printf(m, " uncategorized locks: %11lu\n",
nr_uncategorized);
seq_printf(m, " unused locks: %11lu\n",
nr_unused);
seq_printf(m, " max locking depth: %11u\n",
max_lockdep_depth);
#ifdef CONFIG_PROVE_LOCKING
seq_printf(m, " max bfs queue depth: %11u\n",
max_bfs_queue_depth);
#endif
lockdep_stats_debug_show(m);
seq_printf(m, " debug_locks: %11u\n",
debug_locks);
/*
* Zappped classes and lockdep data buffers reuse statistics.
*/
seq_puts(m, "\n");
seq_printf(m, " zapped classes: %11lu\n",
nr_zapped_classes);
#ifdef CONFIG_PROVE_LOCKING
seq_printf(m, " zapped lock chains: %11lu\n",
nr_zapped_lock_chains);
locking/lockdep: Reuse freed chain_hlocks entries Once a lock class is zapped, all the lock chains that include the zapped class are essentially useless. The lock_chain structure itself can be reused, but not the corresponding chain_hlocks[] entries. Over time, we will run out of chain_hlocks entries while there are still plenty of other lockdep array entries available. To fix this imbalance, we have to make chain_hlocks entries reusable just like the others. As the freed chain_hlocks entries are in blocks of various lengths. A simple bitmap like the one used in the other reusable lockdep arrays isn't applicable. Instead the chain_hlocks entries are put into bucketed lists (MAX_CHAIN_BUCKETS) of chain blocks. Bucket 0 is the variable size bucket which houses chain blocks of size larger than MAX_CHAIN_BUCKETS sorted in decreasing size order. Initially, the whole array is in one chain block (the primordial chain block) in bucket 0. The minimum size of a chain block is 2 chain_hlocks entries. That will be the minimum allocation size. In other word, allocation requests for one chain_hlocks entry will cause 2-entry block to be returned and hence 1 entry will be wasted. Allocation requests for the chain_hlocks are fulfilled first by looking for chain block of matching size. If not found, the first chain block from bucket[0] (the largest one) is split. That can cause hlock entries fragmentation and reduce allocation efficiency if a chain block of size > MAX_CHAIN_BUCKETS is ever zapped and put back to after the primordial chain block. So the MAX_CHAIN_BUCKETS must be large enough that this should seldom happen. By reusing the chain_hlocks entries, we are able to handle workloads that add and zap a lot of lock classes without the risk of running out of chain_hlocks entries as long as the total number of outstanding lock classes at any time remain within a reasonable limit. Two new tracking counters, nr_free_chain_hlocks & nr_large_chain_blocks, are added to track the total number of chain_hlocks entries in the free bucketed lists and the number of large chain blocks in buckets[0] respectively. The nr_free_chain_hlocks replaces nr_chain_hlocks. The nr_large_chain_blocks counter enables to see if we should increase the number of buckets (MAX_CHAIN_BUCKETS) available so as to avoid to avoid the fragmentation problem in bucket[0]. An internal nfsd test that ran for more than an hour and kept on loading and unloading kernel modules could cause the following message to be displayed. [ 4318.443670] BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low! The patched kernel was able to complete the test with a lot of free chain_hlocks entries to spare: # cat /proc/lockdep_stats : dependency chains: 18867 [max: 65536] dependency chain hlocks: 74926 [max: 327680] dependency chain hlocks lost: 0 : zapped classes: 1541 zapped lock chains: 56765 large chain blocks: 1 By changing MAX_CHAIN_BUCKETS to 3 and add a counter for the size of the largest chain block. The system still worked and We got the following lockdep_stats data: dependency chains: 18601 [max: 65536] dependency chain hlocks used: 73133 [max: 327680] dependency chain hlocks lost: 0 : zapped classes: 1541 zapped lock chains: 56702 large chain blocks: 45165 large chain block size: 20165 By running the test again, I was indeed able to cause chain_hlocks entries to get lost: dependency chain hlocks used: 74806 [max: 327680] dependency chain hlocks lost: 575 : large chain blocks: 48737 large chain block size: 7 Due to the fragmentation, it is possible that the "MAX_LOCKDEP_CHAIN_HLOCKS too low!" error can happen even if a lot of of chain_hlocks entries appear to be free. Fortunately, a MAX_CHAIN_BUCKETS value of 16 should be big enough that few variable sized chain blocks, other than the initial one, should ever be present in bucket 0. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200206152408.24165-7-longman@redhat.com
2020-02-06 23:24:08 +08:00
seq_printf(m, " large chain blocks: %11u\n",
nr_large_chain_blocks);
#endif
return 0;
}
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
#ifdef CONFIG_LOCK_STAT
struct lock_stat_data {
struct lock_class *class;
struct lock_class_stats stats;
};
struct lock_stat_seq {
struct lock_stat_data *iter_end;
struct lock_stat_data stats[MAX_LOCKDEP_KEYS];
};
/*
* sort on absolute number of contentions
*/
static int lock_stat_cmp(const void *l, const void *r)
{
const struct lock_stat_data *dl = l, *dr = r;
unsigned long nl, nr;
nl = dl->stats.read_waittime.nr + dl->stats.write_waittime.nr;
nr = dr->stats.read_waittime.nr + dr->stats.write_waittime.nr;
return nr - nl;
}
static void seq_line(struct seq_file *m, char c, int offset, int length)
{
int i;
for (i = 0; i < offset; i++)
seq_puts(m, " ");
for (i = 0; i < length; i++)
seq_printf(m, "%c", c);
seq_puts(m, "\n");
}
static void snprint_time(char *buf, size_t bufsiz, s64 nr)
{
s64 div;
s32 rem;
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
nr += 5; /* for display rounding */
div = div_s64_rem(nr, 1000, &rem);
snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
}
static void seq_time(struct seq_file *m, s64 time)
{
char num[15];
snprint_time(num, sizeof(num), time);
seq_printf(m, " %14s", num);
}
static void seq_lock_time(struct seq_file *m, struct lock_time *lt)
{
seq_printf(m, "%14lu", lt->nr);
seq_time(m, lt->min);
seq_time(m, lt->max);
seq_time(m, lt->total);
seq_time(m, lt->nr ? div_s64(lt->total, lt->nr) : 0);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
}
static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
{
const struct lockdep_subclass_key *ckey;
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
struct lock_class_stats *stats;
struct lock_class *class;
const char *cname;
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
int i, namelen;
char name[39];
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
class = data->class;
stats = &data->stats;
namelen = 38;
if (class->name_version > 1)
namelen -= 2; /* XXX truncates versions > 9 */
if (class->subclass)
namelen -= 2;
rcu_read_lock_sched();
cname = rcu_dereference_sched(class->name);
ckey = rcu_dereference_sched(class->key);
if (!cname && !ckey) {
rcu_read_unlock_sched();
return;
} else if (!cname) {
char str[KSYM_NAME_LEN];
const char *key_name;
key_name = __get_key_name(ckey, str);
snprintf(name, namelen, "%s", key_name);
} else {
snprintf(name, namelen, "%s", cname);
}
rcu_read_unlock_sched();
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
namelen = strlen(name);
if (class->name_version > 1) {
snprintf(name+namelen, 3, "#%d", class->name_version);
namelen += 2;
}
if (class->subclass) {
snprintf(name+namelen, 3, "/%d", class->subclass);
namelen += 2;
}
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
if (stats->write_holdtime.nr) {
if (stats->read_holdtime.nr)
seq_printf(m, "%38s-W:", name);
else
seq_printf(m, "%40s:", name);
seq_printf(m, "%14lu ", stats->bounces[bounce_contended_write]);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
seq_lock_time(m, &stats->write_waittime);
seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_write]);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
seq_lock_time(m, &stats->write_holdtime);
seq_puts(m, "\n");
}
if (stats->read_holdtime.nr) {
seq_printf(m, "%38s-R:", name);
seq_printf(m, "%14lu ", stats->bounces[bounce_contended_read]);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
seq_lock_time(m, &stats->read_waittime);
seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_read]);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
seq_lock_time(m, &stats->read_holdtime);
seq_puts(m, "\n");
}
if (stats->read_waittime.nr + stats->write_waittime.nr == 0)
return;
if (stats->read_holdtime.nr)
namelen += 2;
for (i = 0; i < LOCKSTAT_POINTS; i++) {
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
char ip[32];
if (class->contention_point[i] == 0)
break;
if (!i)
seq_line(m, '-', 40-namelen, namelen);
snprintf(ip, sizeof(ip), "[<%p>]",
(void *)class->contention_point[i]);
seq_printf(m, "%40s %14lu %29s %pS\n",
name, stats->contention_point[i],
ip, (void *)class->contention_point[i]);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
}
for (i = 0; i < LOCKSTAT_POINTS; i++) {
char ip[32];
if (class->contending_point[i] == 0)
break;
if (!i)
seq_line(m, '-', 40-namelen, namelen);
snprintf(ip, sizeof(ip), "[<%p>]",
(void *)class->contending_point[i]);
seq_printf(m, "%40s %14lu %29s %pS\n",
name, stats->contending_point[i],
ip, (void *)class->contending_point[i]);
}
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
if (i) {
seq_puts(m, "\n");
seq_line(m, '.', 0, 40 + 1 + 12 * (14 + 1));
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
seq_puts(m, "\n");
}
}
static void seq_header(struct seq_file *m)
{
seq_puts(m, "lock_stat version 0.4\n");
if (unlikely(!debug_locks))
seq_printf(m, "*WARNING* lock debugging disabled!! - possibly due to a lockdep warning\n");
seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1));
seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s %14s %14s "
"%14s %14s\n",
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
"class name",
"con-bounces",
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
"contentions",
"waittime-min",
"waittime-max",
"waittime-total",
"waittime-avg",
"acq-bounces",
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
"acquisitions",
"holdtime-min",
"holdtime-max",
"holdtime-total",
"holdtime-avg");
seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1));
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
seq_printf(m, "\n");
}
static void *ls_start(struct seq_file *m, loff_t *pos)
{
struct lock_stat_seq *data = m->private;
struct lock_stat_data *iter;
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
if (*pos == 0)
return SEQ_START_TOKEN;
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
iter = data->stats + (*pos - 1);
if (iter >= data->iter_end)
iter = NULL;
return iter;
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
}
static void *ls_next(struct seq_file *m, void *v, loff_t *pos)
{
(*pos)++;
return ls_start(m, pos);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
}
static void ls_stop(struct seq_file *m, void *v)
{
}
static int ls_show(struct seq_file *m, void *v)
{
if (v == SEQ_START_TOKEN)
seq_header(m);
else
seq_stats(m, v);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
return 0;
}
static const struct seq_operations lockstat_ops = {
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
.start = ls_start,
.next = ls_next,
.stop = ls_stop,
.show = ls_show,
};
static int lock_stat_open(struct inode *inode, struct file *file)
{
int res;
struct lock_class *class;
struct lock_stat_seq *data = vmalloc(sizeof(struct lock_stat_seq));
if (!data)
return -ENOMEM;
res = seq_open(file, &lockstat_ops);
if (!res) {
struct lock_stat_data *iter = data->stats;
struct seq_file *m = file->private_data;
list_for_each_entry(class, &all_lock_classes, lock_entry) {
iter->class = class;
iter->stats = lock_stats(class);
iter++;
}
data->iter_end = iter;
sort(data->stats, data->iter_end - data->stats,
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
sizeof(struct lock_stat_data),
lock_stat_cmp, NULL);
m->private = data;
} else
vfree(data);
return res;
}
static ssize_t lock_stat_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct lock_class *class;
char c;
if (count) {
if (get_user(c, buf))
return -EFAULT;
if (c != '0')
return count;
list_for_each_entry(class, &all_lock_classes, lock_entry)
clear_lock_stats(class);
}
return count;
}
static int lock_stat_release(struct inode *inode, struct file *file)
{
struct seq_file *seq = file->private_data;
vfree(seq->private);
return seq_release(inode, file);
}
static const struct proc_ops lock_stat_proc_ops = {
.proc_open = lock_stat_open,
.proc_write = lock_stat_write,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = lock_stat_release,
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
};
#endif /* CONFIG_LOCK_STAT */
static int __init lockdep_proc_init(void)
{
proc_create_seq("lockdep", S_IRUSR, NULL, &lockdep_ops);
#ifdef CONFIG_PROVE_LOCKING
proc_create_seq("lockdep_chains", S_IRUSR, NULL, &lockdep_chains_ops);
#endif
proc_create_single("lockdep_stats", S_IRUSR, NULL, lockdep_stats_show);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
#ifdef CONFIG_LOCK_STAT
proc_create("lock_stat", S_IRUSR | S_IWUSR, NULL, &lock_stat_proc_ops);
lockstat: human readability tweaks Present all this fancy new lock statistics information: *warning, _wide_ output ahead* (output edited for purpose of brevity) # cat /proc/lock_stat lock_stat version 0.1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------- class name contentions waittime-min waittime-max waittime-total acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------- &inode->i_mutex: 14458 6.57 398832.75 2469412.23 6768876 0.34 11398383.65 339410830.89 --------------- &inode->i_mutex 4486 [<ffffffff802a08f9>] pipe_wait+0x86/0x8d &inode->i_mutex 0 [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d &inode->i_mutex 0 [<ffffffff802a0e18>] pipe_read+0x74/0x3a5 &inode->i_mutex 0 [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae ................................................................................................................................................................. &inode->i_data.tree_lock-W: 491 0.27 62.47 493.89 2477833 0.39 468.89 1146584.25 &inode->i_data.tree_lock-R: 65 0.44 4.27 48.78 26288792 0.36 184.62 10197458.24 -------------------------- &inode->i_data.tree_lock 46 [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f &inode->i_data.tree_lock 31 [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba &inode->i_data.tree_lock 0 [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f &inode->i_data.tree_lock 0 [<ffffffff8026f6e4>] find_get_page+0x1a/0x58 ................................................................................................................................................................. proc_inum_idr.lock: 0 0.00 0.00 0.00 36 0.00 65.60 148.26 proc_subdir_lock: 0 0.00 0.00 0.00 3049859 0.00 106.81 1563212.42 shrinker_rwsem-W: 0 0.00 0.00 0.00 5 0.00 1.73 3.68 shrinker_rwsem-R: 0 0.00 0.00 0.00 633 2.57 246.57 10909.76 'contentions' and 'acquisitions' are the number of such events measured (since the last reset). The waittime- and holdtime- (min, max, total) numbers are presented in microseconds. If there are any contention points, the lock class is presented in the block format (as i_mutex and tree_lock above), otherwise a single line of output is presented. The output is sorted on absolute number of contentions (read + write), this should get the worst offenders presented first, so that: # grep : /proc/lock_stat | head will quickly show who's bad. The stats can be reset using: # echo 0 > /proc/lock_stat [bunk@stusta.de: make 2 functions static] [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 16:48:57 +08:00
#endif
return 0;
}
__initcall(lockdep_proc_init);