perf, trace: Optimize tracepoints by removing IRQ-disable from perf/tracepoint interaction

Improves performance.

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1274259525.5605.10352.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 10 insertions, 16 deletions

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index a9775dd7f7fe..126071bc90ab 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -197,20 +197,17 @@ extern void perf_trace_disable(int event_id);
 extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
                                      char *filter_str);
 extern void ftrace_profile_free_filter(struct perf_event *event);
-extern void *
-perf_trace_buf_prepare(int size, unsigned short type, int *rctxp,
-                         unsigned long *irq_flags);
+extern void *perf_trace_buf_prepare(int size, unsigned short type,
+                                    struct pt_regs *regs, int *rctxp);
 
 static inline void
 perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
-                       u64 count, unsigned long irq_flags, struct pt_regs *regs,
-                       void *event)
+                       u64 count, struct pt_regs *regs, void *event)
 {
         struct trace_entry *entry = raw_data;
 
         perf_tp_event(entry->type, addr, count, raw_data, size, regs, event);
         perf_swevent_put_recursion_context(rctx);
-        local_irq_restore(irq_flags);
 }
 #endif
 
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 1016b2162935..f282885057dd 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -768,7 +768,6 @@ perf_trace_templ_##call(struct ftrace_event_call *event_call,		\
         struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
         struct ftrace_raw_##call *entry;                                \
         u64 __addr = 0, __count = 1;                                    \
-        unsigned long irq_flags;                                        \
         int __entry_size;                                               \
         int __data_size;                                                \
         int rctx;                                                       \
@@ -781,17 +780,18 @@ perf_trace_templ_##call(struct ftrace_event_call *event_call,		\
         if (WARN_ONCE(__entry_size > PERF_MAX_TRACE_SIZE,               \
                       "profile buffer not large enough"))               \
                 return;                                                 \
+                                                                        \
         entry = (struct ftrace_raw_##call *)perf_trace_buf_prepare(     \
-                __entry_size, event_call->id, &rctx, &irq_flags);       \
+                __entry_size, event_call->id, __regs, &rctx);           \
         if (!entry)                                                     \
                 return;                                                 \
+                                                                        \
         tstruct                                                         \
                                                                         \
         { assign; }                                                     \
                                                                         \
         perf_trace_buf_submit(entry, __entry_size, rctx, __addr,        \
-                               __count, irq_flags, __regs,              \
-                              event_call->perf_data);                   \
+                               __count, __regs, event_call->perf_data); \
 }
 
 #undef DEFINE_EVENT
@@ -799,13 +799,10 @@ perf_trace_templ_##call(struct ftrace_event_call *event_call,		\
 static notrace void perf_trace_##call(proto)                            \
 {                                                                       \
         struct ftrace_event_call *event_call = &event_##call;           \
-        struct pt_regs *__regs = &get_cpu_var(perf_trace_regs);         \
-                                                                        \
-        perf_fetch_caller_regs(__regs, 1);                              \
-                                                                        \
-        perf_trace_templ_##template(event_call, __regs, args);          \
+        struct pt_regs __regs;                                          \
                                                                         \
-        put_cpu_var(perf_trace_regs);                                   \
+        perf_fetch_caller_regs(&__regs, 1);                             \
+        perf_trace_templ_##template(event_call, &__regs, args);         \
 }
 
 #undef DEFINE_EVENT_PRINT