[PATCH 2/4] threadgroup: rename signal->threadgroup_fork_lock to ->group_rwsem
Tejun Heo
htejun at gmail.com
Sun Sep 4 11:01:18 PDT 2011
From: Tejun Heo <tj at kernel.org>
Make the following renames to prepare for extension of threadgroup
locking.
* s/signal->threadgroup_fork_lock/signal->group_rwsem/
* s/threadgroup_fork_read_lock()/threadgroup_change_begin()/
* s/threadgroup_fork_read_unlock()/threadgroup_change_done()/
* s/threadgroup_fork_write_lock()/threadgroup_lock()/
* s/threadgroup_fork_write_unlock()/threadgroup_unlock()/
This patch doesn't cause any behavior change.
Signed-off-by: Tejun Heo <tj at kernel.org>
Cc: Oleg Nesterov <oleg at redhat.com>
Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: Paul Menage <menage at google.com>
Cc: Li Zefan <lizf at cn.fujitsu.com>
---
include/linux/init_task.h | 9 ++++-----
include/linux/sched.h | 30 +++++++++++++++---------------
kernel/cgroup.c | 12 ++++++------
kernel/fork.c | 8 ++++----
4 files changed, 29 insertions(+), 30 deletions(-)
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index d14e058..3a0d9f2 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -23,11 +23,10 @@ extern struct files_struct init_files;
extern struct fs_struct init_fs;
#ifdef CONFIG_CGROUPS
-#define INIT_THREADGROUP_FORK_LOCK(sig) \
- .threadgroup_fork_lock = \
- __RWSEM_INITIALIZER(sig.threadgroup_fork_lock),
+#define INIT_GROUP_RWSEM(sig) \
+ .group_rwsem = __RWSEM_INITIALIZER(sig.group_rwsem),
#else
-#define INIT_THREADGROUP_FORK_LOCK(sig)
+#define INIT_GROUP_RWSEM(sig)
#endif
#define INIT_SIGNALS(sig) { \
@@ -46,7 +45,7 @@ extern struct fs_struct init_fs;
}, \
.cred_guard_mutex = \
__MUTEX_INITIALIZER(sig.cred_guard_mutex), \
- INIT_THREADGROUP_FORK_LOCK(sig) \
+ INIT_GROUP_RWSEM(sig) \
}
extern struct nsproxy init_nsproxy;
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 6d45ce7..da74d6f 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -635,13 +635,13 @@ struct signal_struct {
#endif
#ifdef CONFIG_CGROUPS
/*
- * The threadgroup_fork_lock prevents threads from forking with
+ * The group_rwsem prevents threads from forking with
* CLONE_THREAD while held for writing. Use this for fork-sensitive
* threadgroup-wide operations. It's taken for reading in fork.c in
* copy_process().
* Currently only needed write-side by cgroups.
*/
- struct rw_semaphore threadgroup_fork_lock;
+ struct rw_semaphore group_rwsem;
#endif
int oom_adj; /* OOM kill score adjustment (bit shift) */
@@ -2364,29 +2364,29 @@ static inline void unlock_task_sighand(struct task_struct *tsk,
spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
}
-/* See the declaration of threadgroup_fork_lock in signal_struct. */
+/* See the declaration of group_rwsem in signal_struct. */
#ifdef CONFIG_CGROUPS
-static inline void threadgroup_fork_read_lock(struct task_struct *tsk)
+static inline void threadgroup_change_begin(struct task_struct *tsk)
{
- down_read(&tsk->signal->threadgroup_fork_lock);
+ down_read(&tsk->signal->group_rwsem);
}
-static inline void threadgroup_fork_read_unlock(struct task_struct *tsk)
+static inline void threadgroup_change_done(struct task_struct *tsk)
{
- up_read(&tsk->signal->threadgroup_fork_lock);
+ up_read(&tsk->signal->group_rwsem);
}
-static inline void threadgroup_fork_write_lock(struct task_struct *tsk)
+static inline void threadgroup_lock(struct task_struct *tsk)
{
- down_write(&tsk->signal->threadgroup_fork_lock);
+ down_write(&tsk->signal->group_rwsem);
}
-static inline void threadgroup_fork_write_unlock(struct task_struct *tsk)
+static inline void threadgroup_unlock(struct task_struct *tsk)
{
- up_write(&tsk->signal->threadgroup_fork_lock);
+ up_write(&tsk->signal->group_rwsem);
}
#else
-static inline void threadgroup_fork_read_lock(struct task_struct *tsk) {}
-static inline void threadgroup_fork_read_unlock(struct task_struct *tsk) {}
-static inline void threadgroup_fork_write_lock(struct task_struct *tsk) {}
-static inline void threadgroup_fork_write_unlock(struct task_struct *tsk) {}
+static inline void threadgroup_change_begin(struct task_struct *tsk) {}
+static inline void threadgroup_change_done(struct task_struct *tsk) {}
+static inline void threadgroup_lock(struct task_struct *tsk) {}
+static inline void threadgroup_unlock(struct task_struct *tsk) {}
#endif
#ifndef __HAVE_THREAD_FUNCTIONS
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index bd1fb5f..e81f403 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1985,8 +1985,8 @@ static int css_set_prefetch(struct cgroup *cgrp, struct css_set *cg,
* @cgrp: the cgroup to attach to
* @leader: the threadgroup leader task_struct of the group to be attached
*
- * Call holding cgroup_mutex and the threadgroup_fork_lock of the leader. Will
- * take task_lock of each thread in leader's threadgroup individually in turn.
+ * Call holding cgroup_mutex and the group_rwsem of the leader. Will take
+ * task_lock of each thread in leader's threadgroup individually in turn.
*/
int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
{
@@ -2012,8 +2012,8 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
* step 0: in order to do expensive, possibly blocking operations for
* every thread, we cannot iterate the thread group list, since it needs
* rcu or tasklist locked. instead, build an array of all threads in the
- * group - threadgroup_fork_lock prevents new threads from appearing,
- * and if threads exit, this will just be an over-estimate.
+ * group - group_rwsem prevents new threads from appearing, and if
+ * threads exit, this will just be an over-estimate.
*/
group_size = get_nr_threads(leader);
/* flex_array supports very large thread-groups better than kmalloc. */
@@ -2246,7 +2246,7 @@ static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup)
}
if (threadgroup)
- threadgroup_fork_write_lock(tsk);
+ threadgroup_lock(tsk);
ret = -ENODEV;
if (cgroup_lock_live_group(cgrp)) {
if (threadgroup)
@@ -2256,7 +2256,7 @@ static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup)
cgroup_unlock();
}
if (threadgroup)
- threadgroup_fork_write_unlock(tsk);
+ threadgroup_unlock(tsk);
put_task_struct(tsk);
return ret;
}
diff --git a/kernel/fork.c b/kernel/fork.c
index fa7beb3..f0e2e56 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -980,7 +980,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sched_autogroup_fork(sig);
#ifdef CONFIG_CGROUPS
- init_rwsem(&sig->threadgroup_fork_lock);
+ init_rwsem(&sig->group_rwsem);
#endif
sig->oom_adj = current->signal->oom_adj;
@@ -1165,7 +1165,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->io_context = NULL;
p->audit_context = NULL;
if (clone_flags & CLONE_THREAD)
- threadgroup_fork_read_lock(current);
+ threadgroup_change_begin(current);
cgroup_fork(p);
#ifdef CONFIG_NUMA
p->mempolicy = mpol_dup(p->mempolicy);
@@ -1377,7 +1377,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
proc_fork_connector(p);
cgroup_post_fork(p);
if (clone_flags & CLONE_THREAD)
- threadgroup_fork_read_unlock(current);
+ threadgroup_change_done(current);
perf_event_fork(p);
return p;
@@ -1417,7 +1417,7 @@ bad_fork_cleanup_policy:
bad_fork_cleanup_cgroup:
#endif
if (clone_flags & CLONE_THREAD)
- threadgroup_fork_read_unlock(current);
+ threadgroup_change_done(current);
cgroup_exit(p, cgroup_callbacks_done);
delayacct_tsk_free(p);
module_put(task_thread_info(p)->exec_domain->module);
--
1.7.6
More information about the Containers
mailing list