kernel_optimize_test/fs/proc/array.c
Eric W. Biederman ab521dc0f8 [PATCH] tty: update the tty layer to work with struct pid
Of kernel subsystems that work with pids the tty layer is probably the largest
consumer.  But it has the nice virtue that the assiation with a session only
lasts until the session leader exits.  Which means that no reference counting
is required.  So using struct pid winds up being a simple optimization to
avoid hash table lookups.

In the long term the use of pid_nr also ensures that when we have multiple pid
spaces mixed everything will work correctly.

Signed-off-by: Eric W. Biederman <eric@maxwell.lnxi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:32 -08:00

489 lines
12 KiB
C

/*
* linux/fs/proc/array.c
*
* Copyright (C) 1992 by Linus Torvalds
* based on ideas by Darren Senn
*
* Fixes:
* Michael. K. Johnson: stat,statm extensions.
* <johnsonm@stolaf.edu>
*
* Pauline Middelink : Made cmdline,envline only break at '\0's, to
* make sure SET_PROCTITLE works. Also removed
* bad '!' which forced address recalculation for
* EVERY character on the current page.
* <middelin@polyware.iaf.nl>
*
* Danny ter Haar : added cpuinfo
* <dth@cistron.nl>
*
* Alessandro Rubini : profile extension.
* <rubini@ipvvis.unipv.it>
*
* Jeff Tranter : added BogoMips field to cpuinfo
* <Jeff_Tranter@Mitel.COM>
*
* Bruno Haible : remove 4K limit for the maps file
* <haible@ma2s2.mathematik.uni-karlsruhe.de>
*
* Yves Arrouye : remove removal of trailing spaces in get_array.
* <Yves.Arrouye@marin.fdn.fr>
*
* Jerome Forissier : added per-CPU time information to /proc/stat
* and /proc/<pid>/cpu extension
* <forissier@isia.cma.fr>
* - Incorporation and non-SMP safe operation
* of forissier patch in 2.1.78 by
* Hans Marcus <crowbar@concepts.nl>
*
* aeb@cwi.nl : /proc/partitions
*
*
* Alan Cox : security fixes.
* <Alan.Cox@linux.org>
*
* Al Viro : safe handling of mm_struct
*
* Gerhard Wichert : added BIGMEM support
* Siemens AG <Gerhard.Wichert@pdb.siemens.de>
*
* Al Viro & Jeff Garzik : moved most of the thing into base.c and
* : proc_misc.c. The rest may eventually go into
* : base.c too.
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/tty.h>
#include <linux/string.h>
#include <linux/mman.h>
#include <linux/proc_fs.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/signal.h>
#include <linux/highmem.h>
#include <linux/file.h>
#include <linux/times.h>
#include <linux/cpuset.h>
#include <linux/rcupdate.h>
#include <linux/delayacct.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/io.h>
#include <asm/processor.h>
#include "internal.h"
/* Gcc optimizes away "strlen(x)" for constant x */
#define ADDBUF(buffer, string) \
do { memcpy(buffer, string, strlen(string)); \
buffer += strlen(string); } while (0)
static inline char * task_name(struct task_struct *p, char * buf)
{
int i;
char * name;
char tcomm[sizeof(p->comm)];
get_task_comm(tcomm, p);
ADDBUF(buf, "Name:\t");
name = tcomm;
i = sizeof(tcomm);
do {
unsigned char c = *name;
name++;
i--;
*buf = c;
if (!c)
break;
if (c == '\\') {
buf[1] = c;
buf += 2;
continue;
}
if (c == '\n') {
buf[0] = '\\';
buf[1] = 'n';
buf += 2;
continue;
}
buf++;
} while (i);
*buf = '\n';
return buf+1;
}
/*
* The task state array is a strange "bitmap" of
* reasons to sleep. Thus "running" is zero, and
* you can test for combinations of others with
* simple bit tests.
*/
static const char *task_state_array[] = {
"R (running)", /* 0 */
"S (sleeping)", /* 1 */
"D (disk sleep)", /* 2 */
"T (stopped)", /* 4 */
"T (tracing stop)", /* 8 */
"Z (zombie)", /* 16 */
"X (dead)" /* 32 */
};
static inline const char * get_task_state(struct task_struct *tsk)
{
unsigned int state = (tsk->state & (TASK_RUNNING |
TASK_INTERRUPTIBLE |
TASK_UNINTERRUPTIBLE |
TASK_STOPPED |
TASK_TRACED)) |
(tsk->exit_state & (EXIT_ZOMBIE |
EXIT_DEAD));
const char **p = &task_state_array[0];
while (state) {
p++;
state >>= 1;
}
return *p;
}
static inline char * task_state(struct task_struct *p, char *buffer)
{
struct group_info *group_info;
int g;
struct fdtable *fdt = NULL;
rcu_read_lock();
buffer += sprintf(buffer,
"State:\t%s\n"
"SleepAVG:\t%lu%%\n"
"Tgid:\t%d\n"
"Pid:\t%d\n"
"PPid:\t%d\n"
"TracerPid:\t%d\n"
"Uid:\t%d\t%d\t%d\t%d\n"
"Gid:\t%d\t%d\t%d\t%d\n",
get_task_state(p),
(p->sleep_avg/1024)*100/(1020000000/1024),
p->tgid, p->pid,
pid_alive(p) ? rcu_dereference(p->real_parent)->tgid : 0,
pid_alive(p) && p->ptrace ? rcu_dereference(p->parent)->pid : 0,
p->uid, p->euid, p->suid, p->fsuid,
p->gid, p->egid, p->sgid, p->fsgid);
task_lock(p);
if (p->files)
fdt = files_fdtable(p->files);
buffer += sprintf(buffer,
"FDSize:\t%d\n"
"Groups:\t",
fdt ? fdt->max_fds : 0);
rcu_read_unlock();
group_info = p->group_info;
get_group_info(group_info);
task_unlock(p);
for (g = 0; g < min(group_info->ngroups,NGROUPS_SMALL); g++)
buffer += sprintf(buffer, "%d ", GROUP_AT(group_info,g));
put_group_info(group_info);
buffer += sprintf(buffer, "\n");
return buffer;
}
static char * render_sigset_t(const char *header, sigset_t *set, char *buffer)
{
int i, len;
len = strlen(header);
memcpy(buffer, header, len);
buffer += len;
i = _NSIG;
do {
int x = 0;
i -= 4;
if (sigismember(set, i+1)) x |= 1;
if (sigismember(set, i+2)) x |= 2;
if (sigismember(set, i+3)) x |= 4;
if (sigismember(set, i+4)) x |= 8;
*buffer++ = (x < 10 ? '0' : 'a' - 10) + x;
} while (i >= 4);
*buffer++ = '\n';
*buffer = 0;
return buffer;
}
static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
sigset_t *catch)
{
struct k_sigaction *k;
int i;
k = p->sighand->action;
for (i = 1; i <= _NSIG; ++i, ++k) {
if (k->sa.sa_handler == SIG_IGN)
sigaddset(ign, i);
else if (k->sa.sa_handler != SIG_DFL)
sigaddset(catch, i);
}
}
static inline char * task_sig(struct task_struct *p, char *buffer)
{
unsigned long flags;
sigset_t pending, shpending, blocked, ignored, caught;
int num_threads = 0;
unsigned long qsize = 0;
unsigned long qlim = 0;
sigemptyset(&pending);
sigemptyset(&shpending);
sigemptyset(&blocked);
sigemptyset(&ignored);
sigemptyset(&caught);
rcu_read_lock();
if (lock_task_sighand(p, &flags)) {
pending = p->pending.signal;
shpending = p->signal->shared_pending.signal;
blocked = p->blocked;
collect_sigign_sigcatch(p, &ignored, &caught);
num_threads = atomic_read(&p->signal->count);
qsize = atomic_read(&p->user->sigpending);
qlim = p->signal->rlim[RLIMIT_SIGPENDING].rlim_cur;
unlock_task_sighand(p, &flags);
}
rcu_read_unlock();
buffer += sprintf(buffer, "Threads:\t%d\n", num_threads);
buffer += sprintf(buffer, "SigQ:\t%lu/%lu\n", qsize, qlim);
/* render them all */
buffer = render_sigset_t("SigPnd:\t", &pending, buffer);
buffer = render_sigset_t("ShdPnd:\t", &shpending, buffer);
buffer = render_sigset_t("SigBlk:\t", &blocked, buffer);
buffer = render_sigset_t("SigIgn:\t", &ignored, buffer);
buffer = render_sigset_t("SigCgt:\t", &caught, buffer);
return buffer;
}
static inline char *task_cap(struct task_struct *p, char *buffer)
{
return buffer + sprintf(buffer, "CapInh:\t%016x\n"
"CapPrm:\t%016x\n"
"CapEff:\t%016x\n",
cap_t(p->cap_inheritable),
cap_t(p->cap_permitted),
cap_t(p->cap_effective));
}
int proc_pid_status(struct task_struct *task, char * buffer)
{
char * orig = buffer;
struct mm_struct *mm = get_task_mm(task);
buffer = task_name(task, buffer);
buffer = task_state(task, buffer);
if (mm) {
buffer = task_mem(mm, buffer);
mmput(mm);
}
buffer = task_sig(task, buffer);
buffer = task_cap(task, buffer);
buffer = cpuset_task_status_allowed(task, buffer);
#if defined(CONFIG_S390)
buffer = task_show_regs(task, buffer);
#endif
return buffer - orig;
}
static int do_task_stat(struct task_struct *task, char * buffer, int whole)
{
unsigned long vsize, eip, esp, wchan = ~0UL;
long priority, nice;
int tty_pgrp = -1, tty_nr = 0;
sigset_t sigign, sigcatch;
char state;
int res;
pid_t ppid = 0, pgid = -1, sid = -1;
int num_threads = 0;
struct mm_struct *mm;
unsigned long long start_time;
unsigned long cmin_flt = 0, cmaj_flt = 0;
unsigned long min_flt = 0, maj_flt = 0;
cputime_t cutime, cstime, utime, stime;
unsigned long rsslim = 0;
char tcomm[sizeof(task->comm)];
unsigned long flags;
state = *get_task_state(task);
vsize = eip = esp = 0;
mm = get_task_mm(task);
if (mm) {
vsize = task_vsize(mm);
eip = KSTK_EIP(task);
esp = KSTK_ESP(task);
}
get_task_comm(tcomm, task);
sigemptyset(&sigign);
sigemptyset(&sigcatch);
cutime = cstime = utime = stime = cputime_zero;
rcu_read_lock();
if (lock_task_sighand(task, &flags)) {
struct signal_struct *sig = task->signal;
if (sig->tty) {
tty_pgrp = pid_nr(sig->tty->pgrp);
tty_nr = new_encode_dev(tty_devnum(sig->tty));
}
num_threads = atomic_read(&sig->count);
collect_sigign_sigcatch(task, &sigign, &sigcatch);
cmin_flt = sig->cmin_flt;
cmaj_flt = sig->cmaj_flt;
cutime = sig->cutime;
cstime = sig->cstime;
rsslim = sig->rlim[RLIMIT_RSS].rlim_cur;
/* add up live thread stats at the group level */
if (whole) {
struct task_struct *t = task;
do {
min_flt += t->min_flt;
maj_flt += t->maj_flt;
utime = cputime_add(utime, t->utime);
stime = cputime_add(stime, t->stime);
t = next_thread(t);
} while (t != task);
min_flt += sig->min_flt;
maj_flt += sig->maj_flt;
utime = cputime_add(utime, sig->utime);
stime = cputime_add(stime, sig->stime);
}
sid = signal_session(sig);
pgid = process_group(task);
ppid = rcu_dereference(task->real_parent)->tgid;
unlock_task_sighand(task, &flags);
}
rcu_read_unlock();
if (!whole || num_threads<2)
wchan = get_wchan(task);
if (!whole) {
min_flt = task->min_flt;
maj_flt = task->maj_flt;
utime = task->utime;
stime = task->stime;
}
/* scale priority and nice values from timeslices to -20..20 */
/* to make it look like a "normal" Unix priority/nice value */
priority = task_prio(task);
nice = task_nice(task);
/* Temporary variable needed for gcc-2.96 */
/* convert timespec -> nsec*/
start_time = (unsigned long long)task->start_time.tv_sec * NSEC_PER_SEC
+ task->start_time.tv_nsec;
/* convert nsec -> ticks */
start_time = nsec_to_clock_t(start_time);
res = sprintf(buffer,"%d (%s) %c %d %d %d %d %d %lu %lu \
%lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
%lu %lu %lu %lu %lu %lu %lu %lu %d %d %lu %lu %llu\n",
task->pid,
tcomm,
state,
ppid,
pgid,
sid,
tty_nr,
tty_pgrp,
task->flags,
min_flt,
cmin_flt,
maj_flt,
cmaj_flt,
cputime_to_clock_t(utime),
cputime_to_clock_t(stime),
cputime_to_clock_t(cutime),
cputime_to_clock_t(cstime),
priority,
nice,
num_threads,
start_time,
vsize,
mm ? get_mm_rss(mm) : 0,
rsslim,
mm ? mm->start_code : 0,
mm ? mm->end_code : 0,
mm ? mm->start_stack : 0,
esp,
eip,
/* The signal information here is obsolete.
* It must be decimal for Linux 2.0 compatibility.
* Use /proc/#/status for real-time signals.
*/
task->pending.signal.sig[0] & 0x7fffffffUL,
task->blocked.sig[0] & 0x7fffffffUL,
sigign .sig[0] & 0x7fffffffUL,
sigcatch .sig[0] & 0x7fffffffUL,
wchan,
0UL,
0UL,
task->exit_signal,
task_cpu(task),
task->rt_priority,
task->policy,
(unsigned long long)delayacct_blkio_ticks(task));
if(mm)
mmput(mm);
return res;
}
int proc_tid_stat(struct task_struct *task, char * buffer)
{
return do_task_stat(task, buffer, 0);
}
int proc_tgid_stat(struct task_struct *task, char * buffer)
{
return do_task_stat(task, buffer, 1);
}
int proc_pid_statm(struct task_struct *task, char *buffer)
{
int size = 0, resident = 0, shared = 0, text = 0, lib = 0, data = 0;
struct mm_struct *mm = get_task_mm(task);
if (mm) {
size = task_statm(mm, &shared, &text, &data, &resident);
mmput(mm);
}
return sprintf(buffer,"%d %d %d %d %d %d %d\n",
size, resident, shared, text, lib, data, 0);
}