Merge branch 'master' into export-slabh

[sfrench/cifs-2.6.git] / kernel / perf_event.c

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 574ee58a3046a4bff950aa9051e73a2d5dfd7d8b..2f3fbf84215a940cc40eccef9c8304964d10906f 100644 (file)
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -15,6 +15,7 @@
 #include <linux/smp.h>
 #include <linux/file.h>
 #include <linux/poll.h>
+#include <linux/slab.h>
 #include <linux/sysfs.h>
 #include <linux/dcache.h>
 #include <linux/percpu.h>
@@ -1164,11 +1165,9 @@ 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;
@@ -2786,12 +2785,11 @@ __weak struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
        return NULL;
 }
 
-#ifdef CONFIG_EVENT_TRACING
 __weak
 void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int skip)
 {
 }
-#endif
+
 
 /*
  * Output
@@ -3378,15 +3376,23 @@ static void perf_event_task_output(struct perf_event *event,
                                     struct perf_task_event *task_event)
 {
        struct perf_output_handle handle;
-       int size;
        struct task_struct *task = task_event->task;
-       int ret;
+       unsigned long flags;
+       int size, ret;
+
+       /*
+        * If this CPU attempts to acquire an rq lock held by a CPU spinning
+        * in perf_output_lock() from interrupt context, it's game over.
+        */
+       local_irq_save(flags);
 
        size  = task_event->event_id.header.size;
        ret = perf_output_begin(&handle, event, size, 0, 0);
 
-       if (ret)
+       if (ret) {
+               local_irq_restore(flags);
                return;
+       }
 
        task_event->event_id.pid = perf_event_pid(event, task);
        task_event->event_id.ppid = perf_event_pid(event, current);
@@ -3397,6 +3403,7 @@ static void perf_event_task_output(struct perf_event *event,
        perf_output_put(&handle, task_event->event_id);
 
        perf_output_end(&handle);
+       local_irq_restore(flags);
 }
 
 static int perf_event_task_match(struct perf_event *event)