AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

[PATCH] Decrease number of pointer derefs in exit.c

Browse Source 
Decrease the number of pointer derefs in kernel/exit.c

Benefits of the patch:
 - Fewer pointer dereferences should make the code slightly faster.
 - Size of generated code is smaller
 - improved readability

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Jesper Juhl 2006-01-09 20:54:39 -08:00 committed by Linus Torvalds
parent a547dfe956
commit 3795e1616f
1 changed files with 21 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
kernel/exit.c
View File

@ -1071,6 +1071,9 @@ static int wait_task_zombie(task_t *p, int noreap,
}
if (likely(p->real_parent == p->parent) && likely(p->signal)) {
struct signal_struct *psig;
struct signal_struct *sig;
/*
* The resource counters for the group leader are in its
* own task_struct. Those for dead threads in the group
@ -1087,24 +1090,26 @@ static int wait_task_zombie(task_t *p, int noreap,
* here reaping other children at the same time.
*/
spin_lock_irq(&p->parent->sighand->siglock);
p->parent->signal->cutime =
cputime_add(p->parent->signal->cutime,
psig = p->parent->signal;
sig = p->signal;
psig->cutime =
cputime_add(psig->cutime,
cputime_add(p->utime,
cputime_add(p->signal->utime,
p->signal->cutime)));
p->parent->signal->cstime =
cputime_add(p->parent->signal->cstime,
cputime_add(sig->utime,
sig->cutime)));
psig->cstime =
cputime_add(psig->cstime,
cputime_add(p->stime,
cputime_add(p->signal->stime,
p->signal->cstime)));
p->parent->signal->cmin_flt +=
p->min_flt + p->signal->min_flt + p->signal->cmin_flt;
p->parent->signal->cmaj_flt +=
p->maj_flt + p->signal->maj_flt + p->signal->cmaj_flt;
p->parent->signal->cnvcsw +=
p->nvcsw + p->signal->nvcsw + p->signal->cnvcsw;
p->parent->signal->cnivcsw +=
p->nivcsw + p->signal->nivcsw + p->signal->cnivcsw;
cputime_add(sig->stime,
sig->cstime)));
psig->cmin_flt +=
p->min_flt + sig->min_flt + sig->cmin_flt;
psig->cmaj_flt +=
p->maj_flt + sig->maj_flt + sig->cmaj_flt;
psig->cnvcsw +=
p->nvcsw + sig->nvcsw + sig->cnvcsw;
psig->cnivcsw +=
p->nivcsw + sig->nivcsw + sig->cnivcsw;
spin_unlock_irq(&p->parent->sighand->siglock);
}