aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorNeil Horman <nhorman@tuxdriver.com>2007-10-18 23:40:37 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-19 11:53:42 -0700
commitd85f50d5e1aa99ab082035f94265847521819e58 (patch)
treee0c96611352d760dfa54199e706fc76ce8975871
parent14ed9d23aa9acd79210a92ac561a728b42a8e281 (diff)
downloadvexpress-lsk-d85f50d5e1aa99ab082035f94265847521819e58.tar.gz
proc: export a processes resource limits via /proc/pid
Currently, there exists no method for a process to query the resource limits of another process. They can be inferred via some mechanisms but they cannot be explicitly determined. Given that this information can be usefull to know during the debugging of an application, I've written this patch which exports all of a processes limits via /proc/<pid>/limits. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> 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>
-rw-r--r--fs/proc/base.c75
1 files changed, 75 insertions, 0 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 991482811f1..54c2e5621af 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -63,6 +63,7 @@
#include <linux/mm.h>
#include <linux/rcupdate.h>
#include <linux/kallsyms.h>
+#include <linux/resource.h>
#include <linux/module.h>
#include <linux/mount.h>
#include <linux/security.h>
@@ -303,6 +304,78 @@ static int proc_oom_score(struct task_struct *task, char *buffer)
return sprintf(buffer, "%lu\n", points);
}
+struct limit_names {
+ char *name;
+ char *unit;
+};
+
+static const struct limit_names lnames[RLIM_NLIMITS] = {
+ [RLIMIT_CPU] = {"Max cpu time", "ms"},
+ [RLIMIT_FSIZE] = {"Max file size", "bytes"},
+ [RLIMIT_DATA] = {"Max data size", "bytes"},
+ [RLIMIT_STACK] = {"Max stack size", "bytes"},
+ [RLIMIT_CORE] = {"Max core file size", "bytes"},
+ [RLIMIT_RSS] = {"Max resident set", "bytes"},
+ [RLIMIT_NPROC] = {"Max processes", "processes"},
+ [RLIMIT_NOFILE] = {"Max open files", "files"},
+ [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
+ [RLIMIT_AS] = {"Max address space", "bytes"},
+ [RLIMIT_LOCKS] = {"Max file locks", "locks"},
+ [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
+ [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
+ [RLIMIT_NICE] = {"Max nice priority", NULL},
+ [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
+};
+
+/* Display limits for a process */
+static int proc_pid_limits(struct task_struct *task, char *buffer)
+{
+ unsigned int i;
+ int count = 0;
+ unsigned long flags;
+ char *bufptr = buffer;
+
+ struct rlimit rlim[RLIM_NLIMITS];
+
+ rcu_read_lock();
+ if (!lock_task_sighand(task,&flags)) {
+ rcu_read_unlock();
+ return 0;
+ }
+ memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
+ unlock_task_sighand(task, &flags);
+ rcu_read_unlock();
+
+ /*
+ * print the file header
+ */
+ count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
+ "Limit", "Soft Limit", "Hard Limit", "Units");
+
+ for (i = 0; i < RLIM_NLIMITS; i++) {
+ if (rlim[i].rlim_cur == RLIM_INFINITY)
+ count += sprintf(&bufptr[count], "%-25s %-20s ",
+ lnames[i].name, "unlimited");
+ else
+ count += sprintf(&bufptr[count], "%-25s %-20lu ",
+ lnames[i].name, rlim[i].rlim_cur);
+
+ if (rlim[i].rlim_max == RLIM_INFINITY)
+ count += sprintf(&bufptr[count], "%-20s ", "unlimited");
+ else
+ count += sprintf(&bufptr[count], "%-20lu ",
+ rlim[i].rlim_max);
+
+ if (lnames[i].unit)
+ count += sprintf(&bufptr[count], "%-10s\n",
+ lnames[i].unit);
+ else
+ count += sprintf(&bufptr[count], "\n");
+ }
+
+ return count;
+}
+
/************************************************************************/
/* Here the fs part begins */
/************************************************************************/
@@ -2110,6 +2183,7 @@ static const struct pid_entry tgid_base_stuff[] = {
REG("environ", S_IRUSR, environ),
INF("auxv", S_IRUSR, pid_auxv),
INF("status", S_IRUGO, pid_status),
+ INF("limits", S_IRUSR, pid_limits),
#ifdef CONFIG_SCHED_DEBUG
REG("sched", S_IRUGO|S_IWUSR, pid_sched),
#endif
@@ -2435,6 +2509,7 @@ static const struct pid_entry tid_base_stuff[] = {
REG("environ", S_IRUSR, environ),
INF("auxv", S_IRUSR, pid_auxv),
INF("status", S_IRUGO, pid_status),
+ INF("limits", S_IRUSR, pid_limits),
#ifdef CONFIG_SCHED_DEBUG
REG("sched", S_IRUGO|S_IWUSR, pid_sched),
#endif