diff options
| author | Pavel Emelyanov <xemul@openvz.org> | 2008-04-29 01:00:08 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-04-29 08:06:09 -0700 |
| commit | d447ea2f30ec60370ddb99a668e5ac12995f043d (patch) | |
| tree | f5d53c03d32323f3e916237f8ec0e0b2572f93b0 | |
| parent | 46ae220bea40bd1cf4abec2d5cdfb4f9396c7115 (diff) | |
cgroups: add the trigger callback to struct cftype
Trigger callback can be used to receive a kick-up from the user space. The
string written is ignored.
The cftype->private is used for multiplexing events.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Paul Menage <menage@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/cgroup.h | 8 | ||||
| -rw-r--r-- | kernel/cgroup.c | 4 |
2 files changed, 12 insertions, 0 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 785a01cfb49d..2d1d151258cf 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -243,6 +243,14 @@ struct cftype { */ int (*write_s64) (struct cgroup *cgrp, struct cftype *cft, s64 val); + /* + * trigger() callback can be used to get some kick from the + * userspace, when the actual string written is not important + * at all. The private field can be used to determine the + * kick type for multiplexing. + */ + int (*trigger)(struct cgroup *cgrp, unsigned int event); + int (*release) (struct inode *inode, struct file *file); }; diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 436e26f4d624..7c8cc5141877 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1410,6 +1410,10 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *buf, return cft->write(cgrp, cft, file, buf, nbytes, ppos); if (cft->write_u64 || cft->write_s64) return cgroup_write_X64(cgrp, cft, file, buf, nbytes, ppos); + if (cft->trigger) { + int ret = cft->trigger(cgrp, (unsigned int)cft->private); + return ret ? ret : nbytes; + } return -EINVAL; } |