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authorLinus Torvalds <torvalds@linux-foundation.org>2008-12-28 15:21:10 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2008-12-28 15:21:10 -0500
commitb0f4b285d7ed174804658539129a834270f4829a (patch)
treebe7f8dca58075aba2c6a137fcfd4d44c5c333efc /include/linux/compiler.h
parentbe9c5ae4eeec2e85527e95647348b8ea4eb25128 (diff)
parent5250d329e38cdf7580faeb9c53c17d3588d7d19c (diff)
Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (241 commits) sched, trace: update trace_sched_wakeup() tracing/ftrace: don't trace on early stage of a secondary cpu boot, v3 Revert "x86: disable X86_PTRACE_BTS" ring-buffer: prevent false positive warning ring-buffer: fix dangling commit race ftrace: enable format arguments checking x86, bts: memory accounting x86, bts: add fork and exit handling ftrace: introduce tracing_reset_online_cpus() helper tracing: fix warnings in kernel/trace/trace_sched_switch.c tracing: fix warning in kernel/trace/trace.c tracing/ring-buffer: remove unused ring_buffer size trace: fix task state printout ftrace: add not to regex on filtering functions trace: better use of stack_trace_enabled for boot up code trace: add a way to enable or disable the stack tracer x86: entry_64 - introduce FTRACE_ frame macro v2 tracing/ftrace: add the printk-msg-only option tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp() x86, bts: correctly report invalid bts records ... Fixed up trivial conflict in scripts/recordmcount.pl due to SH bits being already partly merged by the SH merge.
Diffstat (limited to 'include/linux/compiler.h')
-rw-r--r--include/linux/compiler.h84
1 files changed, 82 insertions, 2 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 98115d9d04da..ea7c6be354b7 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -59,8 +59,88 @@ extern void __chk_io_ptr(const volatile void __iomem *);
59 * specific implementations come from the above header files 59 * specific implementations come from the above header files
60 */ 60 */
61 61
62#define likely(x) __builtin_expect(!!(x), 1) 62struct ftrace_branch_data {
63#define unlikely(x) __builtin_expect(!!(x), 0) 63 const char *func;
64 const char *file;
65 unsigned line;
66 union {
67 struct {
68 unsigned long correct;
69 unsigned long incorrect;
70 };
71 struct {
72 unsigned long miss;
73 unsigned long hit;
74 };
75 };
76};
77
78/*
79 * Note: DISABLE_BRANCH_PROFILING can be used by special lowlevel code
80 * to disable branch tracing on a per file basis.
81 */
82#if defined(CONFIG_TRACE_BRANCH_PROFILING) && !defined(DISABLE_BRANCH_PROFILING)
83void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect);
84
85#define likely_notrace(x) __builtin_expect(!!(x), 1)
86#define unlikely_notrace(x) __builtin_expect(!!(x), 0)
87
88#define __branch_check__(x, expect) ({ \
89 int ______r; \
90 static struct ftrace_branch_data \
91 __attribute__((__aligned__(4))) \
92 __attribute__((section("_ftrace_annotated_branch"))) \
93 ______f = { \
94 .func = __func__, \
95 .file = __FILE__, \
96 .line = __LINE__, \
97 }; \
98 ______r = likely_notrace(x); \
99 ftrace_likely_update(&______f, ______r, expect); \
100 ______r; \
101 })
102
103/*
104 * Using __builtin_constant_p(x) to ignore cases where the return
105 * value is always the same. This idea is taken from a similar patch
106 * written by Daniel Walker.
107 */
108# ifndef likely
109# define likely(x) (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 1))
110# endif
111# ifndef unlikely
112# define unlikely(x) (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 0))
113# endif
114
115#ifdef CONFIG_PROFILE_ALL_BRANCHES
116/*
117 * "Define 'is'", Bill Clinton
118 * "Define 'if'", Steven Rostedt
119 */
120#define if(cond) if (__builtin_constant_p((cond)) ? !!(cond) : \
121 ({ \
122 int ______r; \
123 static struct ftrace_branch_data \
124 __attribute__((__aligned__(4))) \
125 __attribute__((section("_ftrace_branch"))) \
126 ______f = { \
127 .func = __func__, \
128 .file = __FILE__, \
129 .line = __LINE__, \
130 }; \
131 ______r = !!(cond); \
132 if (______r) \
133 ______f.hit++; \
134 else \
135 ______f.miss++; \
136 ______r; \
137 }))
138#endif /* CONFIG_PROFILE_ALL_BRANCHES */
139
140#else
141# define likely(x) __builtin_expect(!!(x), 1)
142# define unlikely(x) __builtin_expect(!!(x), 0)
143#endif
64 144
65/* Optimization barrier */ 145/* Optimization barrier */
66#ifndef barrier 146#ifndef barrier