The patch titled
pacct: add pacct_struct to fix some pacct bugs.
has been added to the -mm tree. Its filename is
pacct-two-phase-process-accounting.patch
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: pacct: add pacct_struct to fix some pacct bugs.
From: KaiGai Kohei <kaigai@xxxxxxxxxxxxx>
The pacct facility need an i/o operation when an accounting record is
generated. There is a possibility to wake OOM killer up. If OOM killer is
activated, it kills some processes to make them release process memory
regions.
But acct_process() is called in the killed processes context before calling
exit_mm(), so those processes cannot release own memory. In the results, any
processes stop in this point and it finally cause a system stall.
---- in kernel/exit.c : do_exit() ------------
group_dead = atomic_dec_and_test(&tsk->signal->live);
if (group_dead) {
hrtimer_cancel(&tsk->signal->real_timer);
exit_itimers(tsk->signal);
acct_process(code);
}
:
- snip -
:
exit_mm(tsk);
----------------------------------------------
This patch separates generating an accounting record facility into two-phase.
In the first one, acct_collect() calculate vitual memory size of the process
and stores it into pacct_struct before exit_mm(). Then, acct_process()
generates an accounting record and write it into medium.
Signed-off-by: KaiGai Kohei <kaigai@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
include/linux/acct.h | 4 +++
include/linux/sched.h | 7 +++++
kernel/acct.c | 51 ++++++++++++++++++++++++++++------------
kernel/exit.c | 4 ++-
kernel/fork.c | 1
5 files changed, 51 insertions(+), 16 deletions(-)
diff -puN include/linux/acct.h~pacct-two-phase-process-accounting include/linux/acct.h
--- a/include/linux/acct.h~pacct-two-phase-process-accounting
+++ a/include/linux/acct.h
@@ -121,12 +121,16 @@ struct vfsmount;
struct super_block;
extern void acct_auto_close_mnt(struct vfsmount *m);
extern void acct_auto_close(struct super_block *sb);
+extern void acct_init_pacct(struct pacct_struct *pacct);
+extern void acct_collect();
extern void acct_process(long exitcode);
extern void acct_update_integrals(struct task_struct *tsk);
extern void acct_clear_integrals(struct task_struct *tsk);
#else
#define acct_auto_close_mnt(x) do { } while (0)
#define acct_auto_close(x) do { } while (0)
+#define acct_init_pacct(x) do { } while (0)
+#define acct_collect() do { } while (0)
#define acct_process(x) do { } while (0)
#define acct_update_integrals(x) do { } while (0)
#define acct_clear_integrals(task) do { } while (0)
diff -puN include/linux/sched.h~pacct-two-phase-process-accounting include/linux/sched.h
--- a/include/linux/sched.h~pacct-two-phase-process-accounting
+++ a/include/linux/sched.h
@@ -358,6 +358,10 @@ struct sighand_struct {
spinlock_t siglock;
};
+struct pacct_struct {
+ unsigned long ac_mem;
+};
+
/*
* NOTE! "signal_struct" does not have it's own
* locking, because a shared signal_struct always
@@ -449,6 +453,9 @@ struct signal_struct {
struct key *session_keyring; /* keyring inherited over fork */
struct key *process_keyring; /* keyring private to this process */
#endif
+#ifdef CONFIG_BSD_PROCESS_ACCT
+ struct pacct_struct pacct; /* per-process accounting information */
+#endif
};
/* Context switch must be unlocked if interrupts are to be enabled */
diff -puN kernel/acct.c~pacct-two-phase-process-accounting kernel/acct.c
--- a/kernel/acct.c~pacct-two-phase-process-accounting
+++ a/kernel/acct.c
@@ -421,9 +421,9 @@ static u32 encode_float(u64 value)
*/
static void do_acct_process(long exitcode, struct file *file)
{
+ struct pacct_struct *pacct = ¤t->signal->pacct;
acct_t ac;
mm_segment_t fs;
- unsigned long vsize;
unsigned long flim;
u64 elapsed;
u64 run_time;
@@ -505,20 +505,9 @@ static void do_acct_process(long exitcod
ac.ac_flag |= ACORE;
if (current->flags & PF_SIGNALED)
ac.ac_flag |= AXSIG;
-
- vsize = 0;
- if (current->mm) {
- struct vm_area_struct *vma;
- down_read(¤t->mm->mmap_sem);
- vma = current->mm->mmap;
- while (vma) {
- vsize += vma->vm_end - vma->vm_start;
- vma = vma->vm_next;
- }
- up_read(¤t->mm->mmap_sem);
- }
- vsize = vsize / 1024;
- ac.ac_mem = encode_comp_t(vsize);
+ spin_lock(¤t->sighand->siglock);
+ ac.ac_mem = encode_comp_t(pacct->ac_mem);
+ spin_unlock(¤t->sighand->siglock);
ac.ac_io = encode_comp_t(0 /* current->io_usage */); /* %% */
ac.ac_rw = encode_comp_t(ac.ac_io / 1024);
ac.ac_minflt = encode_comp_t(current->signal->min_flt +
@@ -546,6 +535,38 @@ static void do_acct_process(long exitcod
}
/**
+ * acct_init_pacct - initialize a new pacct_struct
+ */
+void acct_init_pacct(struct pacct_struct *pacct)
+{
+ memset(pacct, 0, sizeof(struct pacct_struct));
+}
+
+/**
+ * acct_collect - collect accounting information into pacct_struct
+ */
+void acct_collect(void)
+{
+ struct pacct_struct *pacct = ¤t->signal->pacct;
+ unsigned long vsize = 0;
+
+ if (current->mm) {
+ struct vm_area_struct *vma;
+ down_read(¤t->mm->mmap_sem);
+ vma = current->mm->mmap;
+ while (vma) {
+ vsize += vma->vm_end - vma->vm_start;
+ vma = vma->vm_next;
+ }
+ up_read(¤t->mm->mmap_sem);
+ }
+
+ spin_lock(¤t->sighand->siglock);
+ pacct->ac_mem = vsize / 1024;
+ spin_unlock(¤t->sighand->siglock);
+}
+
+/**
* acct_process - now just a wrapper around do_acct_process
* @exitcode: task exit code
*
diff -puN kernel/exit.c~pacct-two-phase-process-accounting kernel/exit.c
--- a/kernel/exit.c~pacct-two-phase-process-accounting
+++ a/kernel/exit.c
@@ -894,7 +894,7 @@ fastcall NORET_TYPE void do_exit(long co
if (group_dead) {
hrtimer_cancel(&tsk->signal->real_timer);
exit_itimers(tsk->signal);
- acct_process(code);
+ acct_collect();
}
if (unlikely(tsk->robust_list))
exit_robust_list(tsk);
@@ -906,6 +906,8 @@ fastcall NORET_TYPE void do_exit(long co
audit_free(tsk);
exit_mm(tsk);
+ if (group_dead)
+ acct_process(code);
exit_sem(tsk);
__exit_files(tsk);
__exit_fs(tsk);
diff -puN kernel/fork.c~pacct-two-phase-process-accounting kernel/fork.c
--- a/kernel/fork.c~pacct-two-phase-process-accounting
+++ a/kernel/fork.c
@@ -874,6 +874,7 @@ static inline int copy_signal(unsigned l
tsk->it_prof_expires =
secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur);
}
+ acct_init_pacct(&sig->pacct);
return 0;
}
_
Patches currently in -mm which might be from kaigai@xxxxxxxxxxxxx are
origin.patch
pacct-two-phase-process-accounting.patch
pacct-avoidance-to-refer-the-last-thread-as-a-representation-of-the-process.patch
pacct-none-delayed-process-accounting-accumulation.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
