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>
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index a14122e..d597d30 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1474,13 +1474,6 @@
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 @@
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 @@
{
.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,
},
};