From 4ddf951bf9287e67ea6c450b28d9d7566abd09b7 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <fweisbec@gmail.com>
Date: Mon, 22 Mar 2010 19:40:03 +0100
Subject: [PATCH] --- yaml --- r: 189425 b: refs/heads/master c:
 e49a5bd38159dfb1928fd25b173bc9de4bbadb21 h: refs/heads/master i:   189423:
 18a714cdf478e6d3514fa3357e1c52c7910ec873 v: v3

---
 [refs]                                 |  2 +-
 trunk/arch/x86/kernel/cpu/perf_event.c |  2 --
 trunk/include/linux/perf_event.h       | 21 ++++++++++++++-------
 trunk/kernel/perf_event.c              |  4 +---
 4 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/[refs] b/[refs]
index 55fa9da50a72..49b8ec690e0d 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: eb1e79611cc9bfe21978230e3521e77ea2d7874a
+refs/heads/master: e49a5bd38159dfb1928fd25b173bc9de4bbadb21
diff --git a/trunk/arch/x86/kernel/cpu/perf_event.c b/trunk/arch/x86/kernel/cpu/perf_event.c
index 60398a0d947c..5fb490c6ee5c 100644
--- a/trunk/arch/x86/kernel/cpu/perf_event.c
+++ b/trunk/arch/x86/kernel/cpu/perf_event.c
@@ -1702,7 +1702,6 @@ struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
 	return entry;
 }
 
-#ifdef CONFIG_EVENT_TRACING
 void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int skip)
 {
 	regs->ip = ip;
@@ -1714,4 +1713,3 @@ void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int ski
 	regs->cs = __KERNEL_CS;
 	local_save_flags(regs->flags);
 }
-#endif
diff --git a/trunk/include/linux/perf_event.h b/trunk/include/linux/perf_event.h
index 95477038a72a..c8e375440403 100644
--- a/trunk/include/linux/perf_event.h
+++ b/trunk/include/linux/perf_event.h
@@ -842,13 +842,6 @@ extern atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
 
 extern void __perf_sw_event(u32, u64, int, struct pt_regs *, u64);
 
-static inline void
-perf_sw_event(u32 event_id, u64 nr, int nmi, struct pt_regs *regs, u64 addr)
-{
-	if (atomic_read(&perf_swevent_enabled[event_id]))
-		__perf_sw_event(event_id, nr, nmi, regs, addr);
-}
-
 extern void
 perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int skip);
 
@@ -887,6 +880,20 @@ static inline void perf_fetch_caller_regs(struct pt_regs *regs, int skip)
 	return perf_arch_fetch_caller_regs(regs, ip, skip);
 }
 
+static inline void
+perf_sw_event(u32 event_id, u64 nr, int nmi, struct pt_regs *regs, u64 addr)
+{
+	if (atomic_read(&perf_swevent_enabled[event_id])) {
+		struct pt_regs hot_regs;
+
+		if (!regs) {
+			perf_fetch_caller_regs(&hot_regs, 1);
+			regs = &hot_regs;
+		}
+		__perf_sw_event(event_id, nr, nmi, regs, addr);
+	}
+}
+
 extern void __perf_event_mmap(struct vm_area_struct *vma);
 
 static inline void perf_event_mmap(struct vm_area_struct *vma)
diff --git a/trunk/kernel/perf_event.c b/trunk/kernel/perf_event.c
index 574ee58a3046..b0feb4795af3 100644
--- a/trunk/kernel/perf_event.c
+++ b/trunk/kernel/perf_event.c
@@ -1164,11 +1164,9 @@ void perf_event_task_sched_out(struct task_struct *task,
 	struct perf_event_context *ctx = task->perf_event_ctxp;
 	struct perf_event_context *next_ctx;
 	struct perf_event_context *parent;
-	struct pt_regs *regs;
 	int do_switch = 1;
 
-	regs = task_pt_regs(task);
-	perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, regs, 0);
+	perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, NULL, 0);
 
 	if (likely(!ctx || !cpuctx->task_ctx))
 		return;