kernel_optimize_test/fs/proc
Chinwen Chang ff9f47f6f0 mm: proc: smaps_rollup: do not stall write attempts on mmap_lock
smaps_rollup will try to grab mmap_lock and go through the whole vma list
until it finishes the iterating.  When encountering large processes, the
mmap_lock will be held for a longer time, which may block other write
requests like mmap and munmap from progressing smoothly.

There are upcoming mmap_lock optimizations like range-based locks, but the
lock applied to smaps_rollup would be the coarse type, which doesn't avoid
the occurrence of unpleasant contention.

To solve aforementioned issue, we add a check which detects whether anyone
wants to grab mmap_lock for write attempts.

Signed-off-by: Chinwen Chang <chinwen.chang@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Song Liu <songliubraving@fb.com>
Cc: Jimmy Assarsson <jimmyassarsson@gmail.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Daniel Kiss <daniel.kiss@arm.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Link: http://lkml.kernel.org/r/1597715898-3854-4-git-send-email-chinwen.chang@mediatek.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:31 -07:00
..
array.c seccomp: Report number of loaded filters in /proc/$pid/status 2020-07-10 16:01:51 -07:00
base.c mm, oom: make the calculation of oom badness more accurate 2020-08-12 10:57:56 -07:00
bootconfig.c proc/bootconfig: Fix to use correct quotes for value 2020-06-16 21:21:03 -04:00
cmdline.c
consoles.c
cpuinfo.c proc: faster open/read/close with "permanent" files 2020-04-07 10:43:42 -07:00
devices.c block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
fd.c
fd.h
generic.c proc: add option to mount only a pids subset 2020-04-22 10:51:22 -05:00
inode.c proc: Use new_inode not new_inode_pseudo 2020-06-12 14:13:33 -05:00
internal.h proc: faster open/read/close with "permanent" files 2020-04-07 10:43:42 -07:00
interrupts.c
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
kcore.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
kmsg.c proc: faster open/read/close with "permanent" files 2020-04-07 10:43:42 -07:00
loadavg.c
Makefile proc: bootconfig: Add /proc/bootconfig to show boot config list 2020-01-13 13:19:39 -05:00
meminfo.c proc/meminfo: avoid open coded reading of vm_committed_as 2020-08-07 11:33:26 -07:00
namespaces.c Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-01-29 11:20:24 -08:00
nommu.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
page.c mm: Add PG_arch_2 page flag 2020-09-04 12:46:06 +01:00
proc_net.c bpf: Refactor to provide aux info to bpf_iter_init_seq_priv_t 2020-07-25 20:16:32 -07:00
proc_sysctl.c Call sysctl_head_finish on error 2020-07-03 14:10:46 -04:00
proc_tty.c
root.c proc: s_fs_info may be NULL when proc_kill_sb is called 2020-06-10 14:54:54 -05:00
self.c proc: Use new_inode not new_inode_pseudo 2020-06-12 14:13:33 -05:00
softirqs.c
stat.c proc: faster open/read/close with "permanent" files 2020-04-07 10:43:42 -07:00
task_mmu.c mm: proc: smaps_rollup: do not stall write attempts on mmap_lock 2020-10-13 18:38:31 -07:00
task_nommu.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
thread_self.c proc: Use new_inode not new_inode_pseudo 2020-06-12 14:13:33 -05:00
uptime.c fs/proc: Respect boottime inside time namespace for /proc/uptime 2020-01-14 12:20:56 +01:00
util.c
version.c
vmcore.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00