+ vfree-dont-schedule-free_work-if-llist_add-returns-false.patch added to -mm tree

+ vfree-dont-schedule-free_work-if-llist_add-returns-false.patch added to -mm tree

[akpm]

Subject: + vfree-dont-schedule-free_work-if-llist_add-returns-false.patch added to -mm tree
To: oleg@redhat.com,viro@zeniv.linux.org.uk
From: akpm@linux-foundation.org
Date: Mon, 17 Jun 2013 16:31:52 -0700


The patch titled
     Subject: vfree: don't schedule free_work() if llist_add() returns false
has been added to the -mm tree.  Its filename is
     vfree-dont-schedule-free_work-if-llist_add-returns-false.patch

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------------------------------------------------------
From: Oleg Nesterov <oleg@redhat.com>
Subject: vfree: don't schedule free_work() if llist_add() returns false

vfree() only needs schedule_work(&p->wq) if p->list was empty, otherwise
vfree_deferred->wq is already pending or it is running and didn't do
llist_del_all() yet.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmalloc.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff -puN mm/vmalloc.c~vfree-dont-schedule-free_work-if-llist_add-returns-false mm/vmalloc.c
--- a/mm/vmalloc.c~vfree-dont-schedule-free_work-if-llist_add-returns-false
+++ a/mm/vmalloc.c
@@ -1477,7 +1477,6 @@ static void __vunmap(const void *addr, i
  *	conventions for vfree() arch-depenedent would be a really bad idea)
  *
  *	NOTE: assumes that the object at *addr has a size >= sizeof(llist_node)
- *	
  */
 void vfree(const void *addr)
 {
@@ -1489,8 +1488,8 @@ void vfree(const void *addr)
 		return;
 	if (unlikely(in_interrupt())) {
 		struct vfree_deferred *p = &__get_cpu_var(vfree_deferred);
-		llist_add((struct llist_node *)addr, &p->list);
-		schedule_work(&p->wq);
+		if (llist_add((struct llist_node *)addr, &p->list))
+			schedule_work(&p->wq);
 	} else
 		__vunmap(addr, 1);
 }
_

Patches currently in -mm which might be from oleg@redhat.com are

linux-next.patch
fput-task_work_add-can-fail-if-the-caller-has-passed-exit_task_work-fix.patch
posix_cpu_timer-consolidate-expiry-time-type.patch
posix_cpu_timers-consolidate-timer-list-cleanups.patch
posix_cpu_timers-consolidate-expired-timers-check.patch
posix-timers-correctly-get-dying-task-time-sample-in-posix_cpu_timer_schedule.patch
posix_timers-fix-racy-timer-delta-caching-on-task-exit.patch
include-linux-schedh-dont-use-task-pid-tgid-in-same_thread_group-has_group_leader_pid.patch
lockdep-introduce-lock_acquire_exclusive-shared-helper-macros.patch
lglock-update-lockdep-annotations-to-report-recursive-local-locks.patch
vfree-dont-schedule-free_work-if-llist_add-returns-false.patch
kernel-sysc-do_sysinfo-use-get_monotonic_boottime.patch
autofs4-allow-autofs-to-work-outside-the-initial-pid-namespace.patch
autofs4-translate-pids-to-the-right-namespace-for-the-daemon.patch
ptrace-x86-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch
ptrace-powerpc-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch
ptrace-arm-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch
ptrace-sh-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch
ptrace-revert-prepare-to-fix-racy-accesses-on-task-breakpoints.patch
ptrace-x86-simplify-the-disable-logic-in-ptrace_write_dr7.patch
ptrace-x86-dont-delay-disable-till-second-pass-in-ptrace_write_dr7.patch
ptrace-x86-introduce-ptrace_register_breakpoint.patch
ptrace-x86-ptrace_write_dr7-should-create-bp-if-disabled.patch
ptrace-x86-cleanup-ptrace_set_debugreg.patch
ptrace-ptrace_detach-should-do-flush_ptrace_hw_breakpointchild.patch
ptrace-x86-flush_ptrace_hw_breakpoint-shoule-clear-the-virtual-debug-registers.patch
x86-kill-tif_debug.patch
ptrace-add-ability-to-get-set-signal-blocked-mask.patch
usermodehelper-kill-the-sub_info-path-check.patch
coredump-format_corename-can-leak-cn-corename.patch
coredump-introduce-cn_vprintf.patch
coredump-cn_vprintf-has-no-reason-to-call-vsnprintf-twice.patch
coredump-kill-cn_escape-introduce-cn_esc_printf.patch
coredump-kill-call_count-add-core_name_size.patch
coredump-%-at-the-end-shouldnt-bypass-core_uses_pid-logic.patch
coredump-%-at-the-end-shouldnt-bypass-core_uses_pid-logic-fix.patch
fs-execc-de_thread-use-change_pid-rather-than-detach_pid-attach_pid.patch
move-exit_task_namespaces-outside-of-exit_notify-fix.patch
exitc-unexport-__set_special_pids.patch
fs-proc-uptimec-uptime_proc_show-use-get_monotonic_boottime.patch
kernel-forkc-copy_process-unify-clone_thread-or-thread_group_leader-code.patch
kernel-forkc-copy_process-dont-add-the-uninitialized-child-to-thread-task-pid-lists.patch
kernel-forkc-copy_process-consolidate-the-lockless-clone_thread-checks.patch
fs-execc-do_execve_common-use-current_user.patch
fs-execc-de_thread-mt-exec-should-update-real_start_time.patch
wait-introduce-wait_event_commonwq-condition-state-timeout.patch
wait-introduce-wait_event_commonwq-condition-state-timeout-checkpatch-fixes.patch
wait-introduce-prepare_to_wait_event.patch
wait-introduce-prepare_to_wait_event-checkpatch-fixes.patch