perf, trace: Optimize tracepoints by using per-tracepoint-per-cpu hlist to track events
Avoid the swevent hash-table by using per-tracepoint
hlists.
Also, avoid conditionals on the fast path by ordering
with probe unregister so that we should never get on
the callback path without the data being there.
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: <20100521090710.473188012@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index f282885..4eb2148 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -768,6 +768,7 @@
struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
struct ftrace_raw_##call *entry; \
u64 __addr = 0, __count = 1; \
+ struct hlist_head *head; \
int __entry_size; \
int __data_size; \
int rctx; \
@@ -790,8 +791,9 @@
\
{ assign; } \
\
+ head = per_cpu_ptr(event_call->perf_events, smp_processor_id());\
perf_trace_buf_submit(entry, __entry_size, rctx, __addr, \
- __count, __regs, event_call->perf_data); \
+ __count, __regs, head); \
}
#undef DEFINE_EVENT