summaryrefslogtreecommitdiff
path: root/kernel/fork.c
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2006-01-08 01:01:37 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-01-08 20:13:40 -0800
commite56d090310d7625ecb43a1eeebd479f04affb48b (patch)
tree2f479215dff4a2d8f3a9ed85200a5bc4f51534be /kernel/fork.c
parent4369ef3c3e9d3bd9b879580678778f558d481e90 (diff)
[PATCH] RCU signal handling
RCU tasklist_lock and RCU signal handling: send signals RCU-read-locked instead of tasklist_lock read-locked. This is a scalability improvement on SMP and a preemption-latency improvement under PREEMPT_RCU. Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: William Irwin <wli@holomorphy.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/fork.c')
-rw-r--r--kernel/fork.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index fb8572a42297..7fe3adfa65cb 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -743,6 +743,14 @@ int unshare_files(void)
EXPORT_SYMBOL(unshare_files);
+void sighand_free_cb(struct rcu_head *rhp)
+{
+ struct sighand_struct *sp;
+
+ sp = container_of(rhp, struct sighand_struct, rcu);
+ kmem_cache_free(sighand_cachep, sp);
+}
+
static inline int copy_sighand(unsigned long clone_flags, struct task_struct * tsk)
{
struct sighand_struct *sig;
@@ -752,7 +760,7 @@ static inline int copy_sighand(unsigned long clone_flags, struct task_struct * t
return 0;
}
sig = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
- tsk->sighand = sig;
+ rcu_assign_pointer(tsk->sighand, sig);
if (!sig)
return -ENOMEM;
spin_lock_init(&sig->siglock);