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

cgroup: make CSS_* flags bit masks instead of bit positions

Browse Source 
Currently, CSS_* flags are defined as bit positions and manipulated
using atomic bitops.  There's no reason to use atomic bitops for them
and bit positions are clunkier to deal with than bit masks.  Make
CSS_* bit masks instead and use the usual C bitwise operators to
access them.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
This commit is contained in:
Tejun Heo 2012-11-19 08:13:36 -08:00
parent febfcef60d
commit 38b53abaa3
2 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
include/linux/cgroup.h
View File

@ -81,7 +81,7 @@ struct cgroup_subsys_state {
/* bits in struct cgroup_subsys_state flags field */
enum {
CSS_ROOT, /* This CSS is the root of the subsystem */
CSS_ROOT = (1 << 0), /* this CSS is the root of the subsystem */
};
/* Caller must verify that the css is not for root cgroup */
@ -100,7 +100,7 @@ static inline void __css_get(struct cgroup_subsys_state *css, int count)
static inline void css_get(struct cgroup_subsys_state *css)
{
/* We don't need to reference count the root state */
if (!test_bit(CSS_ROOT, &css->flags))
if (!(css->flags & CSS_ROOT))
__css_get(css, 1);
}
@ -113,7 +113,7 @@ static inline void css_get(struct cgroup_subsys_state *css)
extern bool __css_tryget(struct cgroup_subsys_state *css);
static inline bool css_tryget(struct cgroup_subsys_state *css)
{
if (test_bit(CSS_ROOT, &css->flags))
if (css->flags & CSS_ROOT)
return true;
return __css_tryget(css);
}
@ -126,7 +126,7 @@ static inline bool css_tryget(struct cgroup_subsys_state *css)
extern void __css_put(struct cgroup_subsys_state *css);
static inline void css_put(struct cgroup_subsys_state *css)
{
if (!test_bit(CSS_ROOT, &css->flags))
if (!(css->flags & CSS_ROOT))
__css_put(css);
}

2
kernel/cgroup.c
View File

@ -4020,7 +4020,7 @@ static void init_cgroup_css(struct cgroup_subsys_state *css,
css->flags = 0;
css->id = NULL;
if (cgrp == dummytop)
set_bit(CSS_ROOT, &css->flags);
css->flags |= CSS_ROOT;
BUG_ON(cgrp->subsys[ss->subsys_id]);
cgrp->subsys[ss->subsys_id] = css;