cgroup files: move notify_on_release file to separate write handler

This patch moves the write handler for the cgroups notify_on_release
file into a separate handler. This handler requires no cgroups locking
since it relies on atomic bitops for synchronization.

Signed-off-by: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Paul Menage 2008-07-25 01:47:01 -07:00 committed by Linus Torvalds
parent 84eea84288
commit 6379c10615

View file

@ -1474,13 +1474,6 @@ static ssize_t cgroup_common_file_write(struct cgroup *cgrp,
case FILE_TASKLIST:
retval = attach_task_by_pid(cgrp, buffer);
break;
case FILE_NOTIFY_ON_RELEASE:
clear_bit(CGRP_RELEASABLE, &cgrp->flags);
if (simple_strtoul(buffer, NULL, 10) != 0)
set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
else
clear_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
break;
default:
retval = -EINVAL;
goto out2;
@ -2252,6 +2245,18 @@ static u64 cgroup_read_notify_on_release(struct cgroup *cgrp,
return notify_on_release(cgrp);
}
static int cgroup_write_notify_on_release(struct cgroup *cgrp,
struct cftype *cft,
u64 val)
{
clear_bit(CGRP_RELEASABLE, &cgrp->flags);
if (val)
set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
else
clear_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
return 0;
}
/*
* for the common functions, 'private' gives the type of file
*/
@ -2268,7 +2273,7 @@ static struct cftype files[] = {
{
.name = "notify_on_release",
.read_u64 = cgroup_read_notify_on_release,
.write = cgroup_common_file_write,
.write_u64 = cgroup_write_notify_on_release,
.private = FILE_NOTIFY_ON_RELEASE,
},
};