The patch titled
coredump: simplify core_state->nr_threads calculation
has been added to the -mm tree. Its filename is
coredump-simplify-core_state-nr_threads-calculation.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: coredump: simplify core_state->nr_threads calculation
From: Oleg Nesterov <oleg@xxxxxxxxxx>
Change zap_process() to return int instead of incrementing
mm->core_state->nr_threads directly. Change zap_threads() to set
mm->core_state only on success.
This patch restores the original size of .text, and more importantly now
->nr_threads is used in two places only.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Roland McGrath <roland@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/exec.c | 33 ++++++++++++++++-----------------
1 file changed, 16 insertions(+), 17 deletions(-)
diff -puN fs/exec.c~coredump-simplify-core_state-nr_threads-calculation fs/exec.c
--- a/fs/exec.c~coredump-simplify-core_state-nr_threads-calculation
+++ a/fs/exec.c
@@ -1504,9 +1504,10 @@ out:
return ispipe;
}
-static void zap_process(struct task_struct *start)
+static int zap_process(struct task_struct *start)
{
struct task_struct *t;
+ int nr = 0;
start->signal->flags = SIGNAL_GROUP_EXIT;
start->signal->group_stop_count = 0;
@@ -1514,31 +1515,32 @@ static void zap_process(struct task_stru
t = start;
do {
if (t != current && t->mm) {
- t->mm->core_state->nr_threads++;
sigaddset(&t->pending.signal, SIGKILL);
signal_wake_up(t, 1);
+ nr++;
}
} while_each_thread(start, t);
+
+ return nr;
}
static inline int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
- int exit_code)
+ struct core_state *core_state, int exit_code)
{
struct task_struct *g, *p;
unsigned long flags;
- int err = -EAGAIN;
+ int nr = -EAGAIN;
spin_lock_irq(&tsk->sighand->siglock);
if (!signal_group_exit(tsk->signal)) {
tsk->signal->group_exit_code = exit_code;
- zap_process(tsk);
- err = 0;
+ nr = zap_process(tsk);
}
spin_unlock_irq(&tsk->sighand->siglock);
- if (err)
- return err;
+ if (unlikely(nr < 0))
+ return nr;
- if (atomic_read(&mm->mm_users) == mm->core_state->nr_threads + 1)
+ if (atomic_read(&mm->mm_users) == nr + 1)
goto done;
/*
* We should find and kill all tasks which use this mm, and we should
@@ -1581,7 +1583,7 @@ static inline int zap_threads(struct tas
if (p->mm) {
if (unlikely(p->mm == mm)) {
lock_task_sighand(p, &flags);
- zap_process(p);
+ nr += zap_process(p);
unlock_task_sighand(p, &flags);
}
break;
@@ -1590,7 +1592,9 @@ static inline int zap_threads(struct tas
}
rcu_read_unlock();
done:
- return mm->core_state->nr_threads;
+ core_state->nr_threads = nr;
+ mm->core_state = core_state;
+ return nr;
}
static int coredump_wait(int exit_code)
@@ -1603,12 +1607,7 @@ static int coredump_wait(int exit_code)
init_completion(&mm->core_done);
init_completion(&core_state.startup);
- core_state.nr_threads = 0;
- mm->core_state = &core_state;
-
- core_waiters = zap_threads(tsk, mm, exit_code);
- if (core_waiters < 0)
- mm->core_state = NULL;
+ core_waiters = zap_threads(tsk, mm, &core_state, exit_code);
up_write(&mm->mmap_sem);
if (unlikely(core_waiters < 0))
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
get_user_pages-fix-possible-page-leak-on-oom.patch
posix-timers-timer_delete-remove-the-bogus-it_process-=-null-check.patch
posix-timers-release_posix_timer-kill-the-bogus-put_task_struct-it_process.patch
signals-collect_signal-remove-the-unneeded-sigismember-check.patch
signals-collect_signal-simplify-the-still_pending-logic.patch
signals-change-collect_signal-to-return-void.patch
__exit_signal-dont-take-rcu-lock.patch
signals-dequeue_signal-dont-check-signal_group_exit-when-setting-signal_stop_dequeued.patch
signals-do_signal_stop-kill-the-signal_unkillable-check.patch
coredump-zap_threads-comments-use-while_each_thread.patch
signals-make-siginfo_t-si_utime-si_sstime-report-times-in-user_hz-not-hz.patch
kernel-signalc-change-vars-pid-and-tgid-types-to-pid_t.patch
include-asm-ptraceh-userspace-headers-cleanup.patch
ptrace-give-more-respect-to-sigkill.patch
ptrace-never-sleep-in-task_traced-if-sigkilled.patch
ptrace-kill-may_ptrace_stop.patch
introduce-pf_kthread-flag.patch
kill-pf_borrowed_mm-in-favour-of-pf_kthread.patch
coredump-zap_threads-must-skip-kernel-threads.patch
coredump-elf_core_dump-skip-kernel-threads.patch
coredump-turn-mm-core_startup_done-into-the-pointer-to-struct-core_state.patch
coredump-move-mm-core_waiters-into-struct-core_state.patch
coredump-simplify-core_state-nr_threads-calculation.patch
coredump-turn-core_state-nr_threads-into-atomic_t.patch
pidns-remove-now-unused-kill_proc-function.patch
pidns-remove-now-unused-find_pid-function.patch
pidns-remove-find_task_by_pid-unused-for-a-long-time.patch
distinct-tgid-tid-i-o-statistics.patch
--
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