xfs: don't serialise adjacent concurrent direct IO appending writes
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / proc / array.c
blob3a1dafd228d14c5e11b142084305e8b60161f84c
1 /*
2 * linux/fs/proc/array.c
4 * Copyright (C) 1992 by Linus Torvalds
5 * based on ideas by Darren Senn
7 * Fixes:
8 * Michael. K. Johnson: stat,statm extensions.
9 * <johnsonm@stolaf.edu>
11 * Pauline Middelink : Made cmdline,envline only break at '\0's, to
12 * make sure SET_PROCTITLE works. Also removed
13 * bad '!' which forced address recalculation for
14 * EVERY character on the current page.
15 * <middelin@polyware.iaf.nl>
17 * Danny ter Haar : added cpuinfo
18 * <dth@cistron.nl>
20 * Alessandro Rubini : profile extension.
21 * <rubini@ipvvis.unipv.it>
23 * Jeff Tranter : added BogoMips field to cpuinfo
24 * <Jeff_Tranter@Mitel.COM>
26 * Bruno Haible : remove 4K limit for the maps file
27 * <haible@ma2s2.mathematik.uni-karlsruhe.de>
29 * Yves Arrouye : remove removal of trailing spaces in get_array.
30 * <Yves.Arrouye@marin.fdn.fr>
32 * Jerome Forissier : added per-CPU time information to /proc/stat
33 * and /proc/<pid>/cpu extension
34 * <forissier@isia.cma.fr>
35 * - Incorporation and non-SMP safe operation
36 * of forissier patch in 2.1.78 by
37 * Hans Marcus <crowbar@concepts.nl>
39 * aeb@cwi.nl : /proc/partitions
42 * Alan Cox : security fixes.
43 * <alan@lxorguk.ukuu.org.uk>
45 * Al Viro : safe handling of mm_struct
47 * Gerhard Wichert : added BIGMEM support
48 * Siemens AG <Gerhard.Wichert@pdb.siemens.de>
50 * Al Viro & Jeff Garzik : moved most of the thing into base.c and
51 * : proc_misc.c. The rest may eventually go into
52 * : base.c too.
55 #include <linux/types.h>
56 #include <linux/errno.h>
57 #include <linux/time.h>
58 #include <linux/kernel.h>
59 #include <linux/kernel_stat.h>
60 #include <linux/tty.h>
61 #include <linux/string.h>
62 #include <linux/mman.h>
63 #include <linux/proc_fs.h>
64 #include <linux/ioport.h>
65 #include <linux/uaccess.h>
66 #include <linux/io.h>
67 #include <linux/mm.h>
68 #include <linux/hugetlb.h>
69 #include <linux/pagemap.h>
70 #include <linux/swap.h>
71 #include <linux/smp.h>
72 #include <linux/signal.h>
73 #include <linux/highmem.h>
74 #include <linux/file.h>
75 #include <linux/fdtable.h>
76 #include <linux/times.h>
77 #include <linux/cpuset.h>
78 #include <linux/rcupdate.h>
79 #include <linux/delayacct.h>
80 #include <linux/seq_file.h>
81 #include <linux/pid_namespace.h>
82 #include <linux/ptrace.h>
83 #include <linux/tracehook.h>
85 #include <asm/pgtable.h>
86 #include <asm/processor.h>
87 #include "internal.h"
89 static inline void task_name(struct seq_file *m, struct task_struct *p)
91 int i;
92 char *buf, *end;
93 char *name;
94 char tcomm[sizeof(p->comm)];
96 get_task_comm(tcomm, p);
98 seq_puts(m, "Name:\t");
99 end = m->buf + m->size;
100 buf = m->buf + m->count;
101 name = tcomm;
102 i = sizeof(tcomm);
103 while (i && (buf < end)) {
104 unsigned char c = *name;
105 name++;
106 i--;
107 *buf = c;
108 if (!c)
109 break;
110 if (c == '\\') {
111 buf++;
112 if (buf < end)
113 *buf++ = c;
114 continue;
116 if (c == '\n') {
117 *buf++ = '\\';
118 if (buf < end)
119 *buf++ = 'n';
120 continue;
122 buf++;
124 m->count = buf - m->buf;
125 seq_putc(m, '\n');
129 * The task state array is a strange "bitmap" of
130 * reasons to sleep. Thus "running" is zero, and
131 * you can test for combinations of others with
132 * simple bit tests.
134 static const char * const task_state_array[] = {
135 "R (running)", /* 0 */
136 "S (sleeping)", /* 1 */
137 "D (disk sleep)", /* 2 */
138 "T (stopped)", /* 4 */
139 "t (tracing stop)", /* 8 */
140 "Z (zombie)", /* 16 */
141 "X (dead)", /* 32 */
142 "x (dead)", /* 64 */
143 "K (wakekill)", /* 128 */
144 "W (waking)", /* 256 */
147 static inline const char *get_task_state(struct task_struct *tsk)
149 unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;
150 const char * const *p = &task_state_array[0];
152 BUILD_BUG_ON(1 + ilog2(TASK_STATE_MAX) != ARRAY_SIZE(task_state_array));
154 while (state) {
155 p++;
156 state >>= 1;
158 return *p;
161 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
162 struct pid *pid, struct task_struct *p)
164 struct group_info *group_info;
165 int g;
166 struct fdtable *fdt = NULL;
167 const struct cred *cred;
168 pid_t ppid, tpid;
170 rcu_read_lock();
171 ppid = pid_alive(p) ?
172 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
173 tpid = 0;
174 if (pid_alive(p)) {
175 struct task_struct *tracer = ptrace_parent(p);
176 if (tracer)
177 tpid = task_pid_nr_ns(tracer, ns);
179 cred = get_task_cred(p);
180 seq_printf(m,
181 "State:\t%s\n"
182 "Tgid:\t%d\n"
183 "Pid:\t%d\n"
184 "PPid:\t%d\n"
185 "TracerPid:\t%d\n"
186 "Uid:\t%d\t%d\t%d\t%d\n"
187 "Gid:\t%d\t%d\t%d\t%d\n",
188 get_task_state(p),
189 task_tgid_nr_ns(p, ns),
190 pid_nr_ns(pid, ns),
191 ppid, tpid,
192 cred->uid, cred->euid, cred->suid, cred->fsuid,
193 cred->gid, cred->egid, cred->sgid, cred->fsgid);
195 task_lock(p);
196 if (p->files)
197 fdt = files_fdtable(p->files);
198 seq_printf(m,
199 "FDSize:\t%d\n"
200 "Groups:\t",
201 fdt ? fdt->max_fds : 0);
202 rcu_read_unlock();
204 group_info = cred->group_info;
205 task_unlock(p);
207 for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
208 seq_printf(m, "%d ", GROUP_AT(group_info, g));
209 put_cred(cred);
211 seq_putc(m, '\n');
214 static void render_sigset_t(struct seq_file *m, const char *header,
215 sigset_t *set)
217 int i;
219 seq_puts(m, header);
221 i = _NSIG;
222 do {
223 int x = 0;
225 i -= 4;
226 if (sigismember(set, i+1)) x |= 1;
227 if (sigismember(set, i+2)) x |= 2;
228 if (sigismember(set, i+3)) x |= 4;
229 if (sigismember(set, i+4)) x |= 8;
230 seq_printf(m, "%x", x);
231 } while (i >= 4);
233 seq_putc(m, '\n');
236 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
237 sigset_t *catch)
239 struct k_sigaction *k;
240 int i;
242 k = p->sighand->action;
243 for (i = 1; i <= _NSIG; ++i, ++k) {
244 if (k->sa.sa_handler == SIG_IGN)
245 sigaddset(ign, i);
246 else if (k->sa.sa_handler != SIG_DFL)
247 sigaddset(catch, i);
251 static inline void task_sig(struct seq_file *m, struct task_struct *p)
253 unsigned long flags;
254 sigset_t pending, shpending, blocked, ignored, caught;
255 int num_threads = 0;
256 unsigned long qsize = 0;
257 unsigned long qlim = 0;
259 sigemptyset(&pending);
260 sigemptyset(&shpending);
261 sigemptyset(&blocked);
262 sigemptyset(&ignored);
263 sigemptyset(&caught);
265 if (lock_task_sighand(p, &flags)) {
266 pending = p->pending.signal;
267 shpending = p->signal->shared_pending.signal;
268 blocked = p->blocked;
269 collect_sigign_sigcatch(p, &ignored, &caught);
270 num_threads = get_nr_threads(p);
271 rcu_read_lock(); /* FIXME: is this correct? */
272 qsize = atomic_read(&__task_cred(p)->user->sigpending);
273 rcu_read_unlock();
274 qlim = task_rlimit(p, RLIMIT_SIGPENDING);
275 unlock_task_sighand(p, &flags);
278 seq_printf(m, "Threads:\t%d\n", num_threads);
279 seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
281 /* render them all */
282 render_sigset_t(m, "SigPnd:\t", &pending);
283 render_sigset_t(m, "ShdPnd:\t", &shpending);
284 render_sigset_t(m, "SigBlk:\t", &blocked);
285 render_sigset_t(m, "SigIgn:\t", &ignored);
286 render_sigset_t(m, "SigCgt:\t", &caught);
289 static void render_cap_t(struct seq_file *m, const char *header,
290 kernel_cap_t *a)
292 unsigned __capi;
294 seq_puts(m, header);
295 CAP_FOR_EACH_U32(__capi) {
296 seq_printf(m, "%08x",
297 a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);
299 seq_putc(m, '\n');
302 static inline void task_cap(struct seq_file *m, struct task_struct *p)
304 const struct cred *cred;
305 kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
307 rcu_read_lock();
308 cred = __task_cred(p);
309 cap_inheritable = cred->cap_inheritable;
310 cap_permitted = cred->cap_permitted;
311 cap_effective = cred->cap_effective;
312 cap_bset = cred->cap_bset;
313 rcu_read_unlock();
315 render_cap_t(m, "CapInh:\t", &cap_inheritable);
316 render_cap_t(m, "CapPrm:\t", &cap_permitted);
317 render_cap_t(m, "CapEff:\t", &cap_effective);
318 render_cap_t(m, "CapBnd:\t", &cap_bset);
321 static inline void task_context_switch_counts(struct seq_file *m,
322 struct task_struct *p)
324 seq_printf(m, "voluntary_ctxt_switches:\t%lu\n"
325 "nonvoluntary_ctxt_switches:\t%lu\n",
326 p->nvcsw,
327 p->nivcsw);
330 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
332 seq_puts(m, "Cpus_allowed:\t");
333 seq_cpumask(m, &task->cpus_allowed);
334 seq_putc(m, '\n');
335 seq_puts(m, "Cpus_allowed_list:\t");
336 seq_cpumask_list(m, &task->cpus_allowed);
337 seq_putc(m, '\n');
340 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
341 struct pid *pid, struct task_struct *task)
343 struct mm_struct *mm = get_task_mm(task);
345 task_name(m, task);
346 task_state(m, ns, pid, task);
348 if (mm) {
349 task_mem(m, mm);
350 mmput(mm);
352 task_sig(m, task);
353 task_cap(m, task);
354 task_cpus_allowed(m, task);
355 cpuset_task_status_allowed(m, task);
356 task_context_switch_counts(m, task);
357 return 0;
360 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
361 struct pid *pid, struct task_struct *task, int whole)
363 unsigned long vsize, eip, esp, wchan = ~0UL;
364 long priority, nice;
365 int tty_pgrp = -1, tty_nr = 0;
366 sigset_t sigign, sigcatch;
367 char state;
368 pid_t ppid = 0, pgid = -1, sid = -1;
369 int num_threads = 0;
370 int permitted;
371 struct mm_struct *mm;
372 unsigned long long start_time;
373 unsigned long cmin_flt = 0, cmaj_flt = 0;
374 unsigned long min_flt = 0, maj_flt = 0;
375 cputime_t cutime, cstime, utime, stime;
376 cputime_t cgtime, gtime;
377 unsigned long rsslim = 0;
378 char tcomm[sizeof(task->comm)];
379 unsigned long flags;
381 state = *get_task_state(task);
382 vsize = eip = esp = 0;
383 permitted = ptrace_may_access(task, PTRACE_MODE_READ);
384 mm = get_task_mm(task);
385 if (mm) {
386 vsize = task_vsize(mm);
387 if (permitted) {
388 eip = KSTK_EIP(task);
389 esp = KSTK_ESP(task);
393 get_task_comm(tcomm, task);
395 sigemptyset(&sigign);
396 sigemptyset(&sigcatch);
397 cutime = cstime = utime = stime = cputime_zero;
398 cgtime = gtime = cputime_zero;
400 if (lock_task_sighand(task, &flags)) {
401 struct signal_struct *sig = task->signal;
403 if (sig->tty) {
404 struct pid *pgrp = tty_get_pgrp(sig->tty);
405 tty_pgrp = pid_nr_ns(pgrp, ns);
406 put_pid(pgrp);
407 tty_nr = new_encode_dev(tty_devnum(sig->tty));
410 num_threads = get_nr_threads(task);
411 collect_sigign_sigcatch(task, &sigign, &sigcatch);
413 cmin_flt = sig->cmin_flt;
414 cmaj_flt = sig->cmaj_flt;
415 cutime = sig->cutime;
416 cstime = sig->cstime;
417 cgtime = sig->cgtime;
418 rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
420 /* add up live thread stats at the group level */
421 if (whole) {
422 struct task_struct *t = task;
423 do {
424 min_flt += t->min_flt;
425 maj_flt += t->maj_flt;
426 gtime = cputime_add(gtime, t->gtime);
427 t = next_thread(t);
428 } while (t != task);
430 min_flt += sig->min_flt;
431 maj_flt += sig->maj_flt;
432 thread_group_times(task, &utime, &stime);
433 gtime = cputime_add(gtime, sig->gtime);
436 sid = task_session_nr_ns(task, ns);
437 ppid = task_tgid_nr_ns(task->real_parent, ns);
438 pgid = task_pgrp_nr_ns(task, ns);
440 unlock_task_sighand(task, &flags);
443 if (permitted && (!whole || num_threads < 2))
444 wchan = get_wchan(task);
445 if (!whole) {
446 min_flt = task->min_flt;
447 maj_flt = task->maj_flt;
448 task_times(task, &utime, &stime);
449 gtime = task->gtime;
452 /* scale priority and nice values from timeslices to -20..20 */
453 /* to make it look like a "normal" Unix priority/nice value */
454 priority = task_prio(task);
455 nice = task_nice(task);
457 /* Temporary variable needed for gcc-2.96 */
458 /* convert timespec -> nsec*/
459 start_time =
460 (unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
461 + task->real_start_time.tv_nsec;
462 /* convert nsec -> ticks */
463 start_time = nsec_to_clock_t(start_time);
465 seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \
466 %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
467 %lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
468 pid_nr_ns(pid, ns),
469 tcomm,
470 state,
471 ppid,
472 pgid,
473 sid,
474 tty_nr,
475 tty_pgrp,
476 task->flags,
477 min_flt,
478 cmin_flt,
479 maj_flt,
480 cmaj_flt,
481 cputime_to_clock_t(utime),
482 cputime_to_clock_t(stime),
483 cputime_to_clock_t(cutime),
484 cputime_to_clock_t(cstime),
485 priority,
486 nice,
487 num_threads,
488 start_time,
489 vsize,
490 mm ? get_mm_rss(mm) : 0,
491 rsslim,
492 mm ? (permitted ? mm->start_code : 1) : 0,
493 mm ? (permitted ? mm->end_code : 1) : 0,
494 (permitted && mm) ? mm->start_stack : 0,
495 esp,
496 eip,
497 /* The signal information here is obsolete.
498 * It must be decimal for Linux 2.0 compatibility.
499 * Use /proc/#/status for real-time signals.
501 task->pending.signal.sig[0] & 0x7fffffffUL,
502 task->blocked.sig[0] & 0x7fffffffUL,
503 sigign .sig[0] & 0x7fffffffUL,
504 sigcatch .sig[0] & 0x7fffffffUL,
505 wchan,
506 0UL,
507 0UL,
508 task->exit_signal,
509 task_cpu(task),
510 task->rt_priority,
511 task->policy,
512 (unsigned long long)delayacct_blkio_ticks(task),
513 cputime_to_clock_t(gtime),
514 cputime_to_clock_t(cgtime));
515 if (mm)
516 mmput(mm);
517 return 0;
520 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
521 struct pid *pid, struct task_struct *task)
523 return do_task_stat(m, ns, pid, task, 0);
526 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
527 struct pid *pid, struct task_struct *task)
529 return do_task_stat(m, ns, pid, task, 1);
532 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
533 struct pid *pid, struct task_struct *task)
535 unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
536 struct mm_struct *mm = get_task_mm(task);
538 if (mm) {
539 size = task_statm(mm, &shared, &text, &data, &resident);
540 mmput(mm);
542 seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
543 size, resident, shared, text, data);
545 return 0;