From 86e2955a31972dc283a7b83990edb1011729c11d Mon Sep 17 00:00:00 2001
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Date: Fri, 16 Feb 2007 01:28:22 -0800
Subject: [PATCH] --- yaml --- r: 48607 b: refs/heads/master c:
 1f2ea0837dbc263ce2a2512c4e73c83df68a6a55 h: refs/heads/master i:   48605:
 6d5d51d678578453423e4321afb491e88f8dd189   48603:
 553dd459fa737af09ef7da291bd434a74adcb6a5   48599:
 3c3e4ad23bafe1aa7a5f9f41bdffef6d7a3b7a75   48591:
 974edcd599947115ec507616481aef7fc4012a15   48575:
 949a61372b94d7ea4ad0842a6bb5fc1c5d16a633 v: v3

---
 [refs]                          |  2 +-
 trunk/kernel/posix-cpu-timers.c | 15 ++++++++++-----
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/[refs] b/[refs]
index c10f83133c65..12cc7be8c997 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7460ed2844ffad7141e30271c0c3da8336e66014
+refs/heads/master: 1f2ea0837dbc263ce2a2512c4e73c83df68a6a55
diff --git a/trunk/kernel/posix-cpu-timers.c b/trunk/kernel/posix-cpu-timers.c
index 7c3e1e6dfb5b..657f77697415 100644
--- a/trunk/kernel/posix-cpu-timers.c
+++ b/trunk/kernel/posix-cpu-timers.c
@@ -304,7 +304,7 @@ int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp)
 		 * should be able to see it.
 		 */
 		struct task_struct *p;
-		read_lock(&tasklist_lock);
+		rcu_read_lock();
 		p = find_task_by_pid(pid);
 		if (p) {
 			if (CPUCLOCK_PERTHREAD(which_clock)) {
@@ -312,12 +312,17 @@ int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp)
 					error = cpu_clock_sample(which_clock,
 								 p, &rtn);
 				}
-			} else if (p->tgid == pid && p->signal) {
-				error = cpu_clock_sample_group(which_clock,
-							       p, &rtn);
+			} else {
+				read_lock(&tasklist_lock);
+				if (p->tgid == pid && p->signal) {
+					error =
+					    cpu_clock_sample_group(which_clock,
+							           p, &rtn);
+				}
+				read_unlock(&tasklist_lock);
 			}
 		}
-		read_unlock(&tasklist_lock);
+		rcu_read_unlock();
 	}
 
 	if (error)