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author | Davidlohr Bueso <dave@stgolabs.net> | 2017-01-03 13:43:11 -0800 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2017-01-14 11:14:11 +0100 |
commit | 0039962a1473f07fd5c8355bd8264be1eb87eb3e (patch) | |
tree | 1611eeff5b2804ebaa7bd89172d85dcd77ac9228 /kernel/exit.c | |
parent | aef591cd3d1ddccb268f64c836d38382007373c1 (diff) | |
download | linux-stable-0039962a1473f07fd5c8355bd8264be1eb87eb3e.tar.gz linux-stable-0039962a1473f07fd5c8355bd8264be1eb87eb3e.tar.bz2 linux-stable-0039962a1473f07fd5c8355bd8264be1eb87eb3e.zip |
kernel/exit: Compute 'current' directly
This patch effectively replaces the tsk pointer dereference (which is
obviously == current), to directly use get_current() macro. In this
case, do_exit() always passes current to exit_mm(), hence we can
simply get rid of the argument. This is also a performance win on some
archs such as x86-64 and ppc64 -- arm64 is no longer an issue.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@stgolabs.net
Cc: mark.rutland@arm.com
Link: http://lkml.kernel.org/r/1483479794-14013-2-git-send-email-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/exit.c')
-rw-r--r-- | kernel/exit.c | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index 8f14b866f9f6..2385d434a46e 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -468,12 +468,12 @@ assign_new_owner: * Turn us into a lazy TLB process if we * aren't already.. */ -static void exit_mm(struct task_struct *tsk) +static void exit_mm(void) { - struct mm_struct *mm = tsk->mm; + struct mm_struct *mm = current->mm; struct core_state *core_state; - mm_release(tsk, mm); + mm_release(current, mm); if (!mm) return; sync_mm_rss(mm); @@ -491,7 +491,7 @@ static void exit_mm(struct task_struct *tsk) up_read(&mm->mmap_sem); - self.task = tsk; + self.task = current; self.next = xchg(&core_state->dumper.next, &self); /* * Implies mb(), the result of xchg() must be visible @@ -501,22 +501,22 @@ static void exit_mm(struct task_struct *tsk) complete(&core_state->startup); for (;;) { - set_task_state(tsk, TASK_UNINTERRUPTIBLE); + set_task_state(current, TASK_UNINTERRUPTIBLE); if (!self.task) /* see coredump_finish() */ break; freezable_schedule(); } - __set_task_state(tsk, TASK_RUNNING); + __set_task_state(current, TASK_RUNNING); down_read(&mm->mmap_sem); } atomic_inc(&mm->mm_count); - BUG_ON(mm != tsk->active_mm); + BUG_ON(mm != current->active_mm); /* more a memory barrier than a real lock */ - task_lock(tsk); - tsk->mm = NULL; + task_lock(current); + current->mm = NULL; up_read(&mm->mmap_sem); enter_lazy_tlb(mm, current); - task_unlock(tsk); + task_unlock(current); mm_update_next_owner(mm); mmput(mm); if (test_thread_flag(TIF_MEMDIE)) @@ -823,7 +823,7 @@ void __noreturn do_exit(long code) tsk->exit_code = code; taskstats_exit(tsk, group_dead); - exit_mm(tsk); + exit_mm(); if (group_dead) acct_process(); |