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authorAndrea Bastoni <bastoni@cs.unc.edu>2010-05-30 19:16:45 -0400
committerAndrea Bastoni <bastoni@cs.unc.edu>2010-05-30 19:16:45 -0400
commitada47b5fe13d89735805b566185f4885f5a3f750 (patch)
tree644b88f8a71896307d71438e9b3af49126ffb22b /kernel/trace/trace_clock.c
parent43e98717ad40a4ae64545b5ba047c7b86aa44f4f (diff)
parent3280f21d43ee541f97f8cda5792150d2dbec20d5 (diff)
Merge branch 'wip-2.6.34' into old-private-masterarchived-private-master
Diffstat (limited to 'kernel/trace/trace_clock.c')
-rw-r--r--kernel/trace/trace_clock.c21
1 files changed, 12 insertions, 9 deletions
diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c
index 20c5f92e28a8..9d589d8dcd1a 100644
--- a/kernel/trace/trace_clock.c
+++ b/kernel/trace/trace_clock.c
@@ -13,6 +13,7 @@
13 * Tracer plugins will chose a default from these clocks. 13 * Tracer plugins will chose a default from these clocks.
14 */ 14 */
15#include <linux/spinlock.h> 15#include <linux/spinlock.h>
16#include <linux/irqflags.h>
16#include <linux/hardirq.h> 17#include <linux/hardirq.h>
17#include <linux/module.h> 18#include <linux/module.h>
18#include <linux/percpu.h> 19#include <linux/percpu.h>
@@ -20,6 +21,8 @@
20#include <linux/ktime.h> 21#include <linux/ktime.h>
21#include <linux/trace_clock.h> 22#include <linux/trace_clock.h>
22 23
24#include "trace.h"
25
23/* 26/*
24 * trace_clock_local(): the simplest and least coherent tracing clock. 27 * trace_clock_local(): the simplest and least coherent tracing clock.
25 * 28 *
@@ -28,17 +31,17 @@
28 */ 31 */
29u64 notrace trace_clock_local(void) 32u64 notrace trace_clock_local(void)
30{ 33{
31 unsigned long flags;
32 u64 clock; 34 u64 clock;
35 int resched;
33 36
34 /* 37 /*
35 * sched_clock() is an architecture implemented, fast, scalable, 38 * sched_clock() is an architecture implemented, fast, scalable,
36 * lockless clock. It is not guaranteed to be coherent across 39 * lockless clock. It is not guaranteed to be coherent across
37 * CPUs, nor across CPU idle events. 40 * CPUs, nor across CPU idle events.
38 */ 41 */
39 raw_local_irq_save(flags); 42 resched = ftrace_preempt_disable();
40 clock = sched_clock(); 43 clock = sched_clock();
41 raw_local_irq_restore(flags); 44 ftrace_preempt_enable(resched);
42 45
43 return clock; 46 return clock;
44} 47}
@@ -69,10 +72,10 @@ u64 notrace trace_clock(void)
69/* keep prev_time and lock in the same cacheline. */ 72/* keep prev_time and lock in the same cacheline. */
70static struct { 73static struct {
71 u64 prev_time; 74 u64 prev_time;
72 raw_spinlock_t lock; 75 arch_spinlock_t lock;
73} trace_clock_struct ____cacheline_aligned_in_smp = 76} trace_clock_struct ____cacheline_aligned_in_smp =
74 { 77 {
75 .lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED, 78 .lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED,
76 }; 79 };
77 80
78u64 notrace trace_clock_global(void) 81u64 notrace trace_clock_global(void)
@@ -81,7 +84,7 @@ u64 notrace trace_clock_global(void)
81 int this_cpu; 84 int this_cpu;
82 u64 now; 85 u64 now;
83 86
84 raw_local_irq_save(flags); 87 local_irq_save(flags);
85 88
86 this_cpu = raw_smp_processor_id(); 89 this_cpu = raw_smp_processor_id();
87 now = cpu_clock(this_cpu); 90 now = cpu_clock(this_cpu);
@@ -92,7 +95,7 @@ u64 notrace trace_clock_global(void)
92 if (unlikely(in_nmi())) 95 if (unlikely(in_nmi()))
93 goto out; 96 goto out;
94 97
95 __raw_spin_lock(&trace_clock_struct.lock); 98 arch_spin_lock(&trace_clock_struct.lock);
96 99
97 /* 100 /*
98 * TODO: if this happens often then maybe we should reset 101 * TODO: if this happens often then maybe we should reset
@@ -104,10 +107,10 @@ u64 notrace trace_clock_global(void)
104 107
105 trace_clock_struct.prev_time = now; 108 trace_clock_struct.prev_time = now;
106 109
107 __raw_spin_unlock(&trace_clock_struct.lock); 110 arch_spin_unlock(&trace_clock_struct.lock);
108 111
109 out: 112 out:
110 raw_local_irq_restore(flags); 113 local_irq_restore(flags);
111 114
112 return now; 115 return now;
113} 116}