[PATCH] pacct: none-delayed process accounting accumulation
In current 2.6.17 implementation, signal_struct refered from task_struct is
used for per-process data structure. The pacct facility also uses it as a
per-process data structure to store stime, utime, minflt, majflt. But those
members are saved in __exit_signal(). It's too late.
For example, if some threads exits at same time, pacct facility has a
possibility to drop accountings for a part of those threads. (see, the
following 'The results of original 2.6.17 kernel') I think accounting
information should be completely collected into the per-process data structure
before writing out an accounting record.
This patch fixes this matter. Accumulation of stime, utime, minflt and majflt
are done before generating accounting record.
[mingo@elte.hu: fix acct_collect() siglock bug found by lockdep]
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/acct.c b/kernel/acct.c
index 4c85fdf..368c4f0 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -428,7 +428,6 @@
u64 elapsed;
u64 run_time;
struct timespec uptime;
- unsigned long jiffies;
/*
* First check to see if there is enough free_space to continue
@@ -469,12 +468,6 @@
#endif
do_div(elapsed, AHZ);
ac.ac_btime = xtime.tv_sec - elapsed;
- jiffies = cputime_to_jiffies(cputime_add(current->utime,
- current->signal->utime));
- ac.ac_utime = encode_comp_t(jiffies_to_AHZ(jiffies));
- jiffies = cputime_to_jiffies(cputime_add(current->stime,
- current->signal->stime));
- ac.ac_stime = encode_comp_t(jiffies_to_AHZ(jiffies));
/* we really need to bite the bullet and change layout */
ac.ac_uid = current->uid;
ac.ac_gid = current->gid;
@@ -497,16 +490,16 @@
read_unlock(&tasklist_lock);
spin_lock(¤t->sighand->siglock);
+ ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
+ ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
ac.ac_flag = pacct->ac_flag;
ac.ac_mem = encode_comp_t(pacct->ac_mem);
+ ac.ac_minflt = encode_comp_t(pacct->ac_minflt);
+ ac.ac_majflt = encode_comp_t(pacct->ac_majflt);
ac.ac_exitcode = pacct->ac_exitcode;
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 +
- current->min_flt);
- ac.ac_majflt = encode_comp_t(current->signal->maj_flt +
- current->maj_flt);
ac.ac_swaps = encode_comp_t(0);
/*
@@ -532,6 +525,7 @@
void acct_init_pacct(struct pacct_struct *pacct)
{
memset(pacct, 0, sizeof(struct pacct_struct));
+ pacct->ac_utime = pacct->ac_stime = cputime_zero;
}
/**
@@ -555,7 +549,7 @@
up_read(¤t->mm->mmap_sem);
}
- spin_lock(¤t->sighand->siglock);
+ spin_lock_irq(¤t->sighand->siglock);
if (group_dead)
pacct->ac_mem = vsize / 1024;
if (thread_group_leader(current)) {
@@ -569,7 +563,11 @@
pacct->ac_flag |= ACORE;
if (current->flags & PF_SIGNALED)
pacct->ac_flag |= AXSIG;
- spin_unlock(¤t->sighand->siglock);
+ pacct->ac_utime = cputime_add(pacct->ac_utime, current->utime);
+ pacct->ac_stime = cputime_add(pacct->ac_stime, current->stime);
+ pacct->ac_minflt += current->min_flt;
+ pacct->ac_majflt += current->maj_flt;
+ spin_unlock_irq(¤t->sighand->siglock);
}
/**