aboutsummaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
authorOleg Nesterov <oleg@tv-sign.ru>2008-07-25 01:47:41 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-25 10:53:39 -0700
commit999d9fc1670bc082928b93b11d1f2e0e417d973c (patch)
treee540e7fd2fab970ba2be5e39ac9f8282a373bc24 /fs
parent32ecb1f26dd50eeaac4e3f4dea4541c97848e459 (diff)
downloadlinux-2.6.34-ux500-999d9fc1670bc082928b93b11d1f2e0e417d973c.tar.gz
coredump: move mm->core_waiters into struct core_state
Move mm->core_waiters into "struct core_state" allocated on stack. This shrinks mm_struct a little bit and allows further changes. This patch mostly does s/core_waiters/core_state. The only essential change is that coredump_wait() must clear mm->core_state before return. The coredump_wait()'s path is uglified and .text grows by 30 bytes, this is fixed by the next patch. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
-rw-r--r--fs/exec.c21
1 files changed, 11 insertions, 10 deletions
diff --git a/fs/exec.c b/fs/exec.c
index 71734568f01..50de3aaff4d 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -722,12 +722,10 @@ static int exec_mmap(struct mm_struct *mm)
* Make sure that if there is a core dump in progress
* for the old mm, we get out and die instead of going
* through with the exec. We must hold mmap_sem around
- * checking core_waiters and changing tsk->mm. The
- * core-inducing thread will increment core_waiters for
- * each thread whose ->mm == old_mm.
+ * checking core_state and changing tsk->mm.
*/
down_read(&old_mm->mmap_sem);
- if (unlikely(old_mm->core_waiters)) {
+ if (unlikely(old_mm->core_state)) {
up_read(&old_mm->mmap_sem);
return -EINTR;
}
@@ -1514,7 +1512,7 @@ static void zap_process(struct task_struct *start)
t = start;
do {
if (t != current && t->mm) {
- t->mm->core_waiters++;
+ t->mm->core_state->nr_threads++;
sigaddset(&t->pending.signal, SIGKILL);
signal_wake_up(t, 1);
}
@@ -1538,11 +1536,11 @@ static inline int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
if (err)
return err;
- if (atomic_read(&mm->mm_users) == mm->core_waiters + 1)
+ if (atomic_read(&mm->mm_users) == mm->core_state->nr_threads + 1)
goto done;
/*
* We should find and kill all tasks which use this mm, and we should
- * count them correctly into mm->core_waiters. We don't take tasklist
+ * count them correctly into ->nr_threads. We don't take tasklist
* lock, but this is safe wrt:
*
* fork:
@@ -1590,7 +1588,7 @@ static inline int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
}
rcu_read_unlock();
done:
- return mm->core_waiters;
+ return mm->core_state->nr_threads;
}
static int coredump_wait(int exit_code)
@@ -1603,9 +1601,12 @@ 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;
up_write(&mm->mmap_sem);
if (unlikely(core_waiters < 0))
@@ -1623,8 +1624,8 @@ static int coredump_wait(int exit_code)
if (core_waiters)
wait_for_completion(&core_state.startup);
+ mm->core_state = NULL;
fail:
- BUG_ON(mm->core_waiters);
return core_waiters;
}
@@ -1702,7 +1703,7 @@ int do_coredump(long signr, int exit_code, struct pt_regs * regs)
/*
* If another thread got here first, or we are not dumpable, bail out.
*/
- if (mm->core_waiters || !get_dumpable(mm)) {
+ if (mm->core_state || !get_dumpable(mm)) {
up_write(&mm->mmap_sem);
goto fail;
}