lkml.org 
[lkml]   [2015]   [Feb]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/8] x86, fpu: unlazy_fpu: don't reset thread.fpu_counter
Date
From: Oleg Nesterov <oleg@redhat.com>

It is not clear why the "else" branch clears ->fpu_counter, this makes
no sense.

If use_eager_fpu() then this has no effect. Otherwise, if we actually
wanted to prevent fpu preload after the context switch we would need to
reset it unconditionally, even if __thread_has_fpu().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
---
arch/x86/kernel/i387.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 47348653503a..c3b92c0975cd 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -122,8 +122,7 @@ void unlazy_fpu(struct task_struct *tsk)
if (__thread_has_fpu(tsk)) {
__save_init_fpu(tsk);
__thread_fpu_end(tsk);
- } else
- tsk->thread.fpu_counter = 0;
+ }
preempt_enable();
}
EXPORT_SYMBOL(unlazy_fpu);
--
1.9.3


\
 
 \ /
  Last update: 2015-02-06 21:21    [W:0.161 / U:0.120 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site