From 4f41c013f553957765902fb01475972f0af3e8e7 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 18 May 2010 18:08:32 +0200 Subject: perf/ftrace: Optimize perf/tracepoint interaction for single events When we've got but a single event per tracepoint there is no reason to try and multiplex it so don't. Signed-off-by: Peter Zijlstra Tested-by: Ingo Molnar Cc: Steven Rostedt Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/trace/trace_event_perf.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'kernel/trace/trace_event_perf.c') diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 0565bb42566..89b780a7c52 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -27,13 +27,15 @@ typedef typeof(unsigned long [PERF_MAX_TRACE_SIZE / sizeof(unsigned long)]) /* Count the events in use (per event id, not per instance) */ static int total_ref_count; -static int perf_trace_event_enable(struct ftrace_event_call *event) +static int perf_trace_event_enable(struct ftrace_event_call *event, void *data) { char *buf; int ret = -ENOMEM; - if (event->perf_refcount++ > 0) + if (event->perf_refcount++ > 0) { + event->perf_data = NULL; return 0; + } if (!total_ref_count) { buf = (char *)alloc_percpu(perf_trace_t); @@ -51,6 +53,7 @@ static int perf_trace_event_enable(struct ftrace_event_call *event) ret = event->perf_event_enable(event); if (!ret) { + event->perf_data = data; total_ref_count++; return 0; } @@ -68,7 +71,7 @@ fail_buf: return ret; } -int perf_trace_enable(int event_id) +int perf_trace_enable(int event_id, void *data) { struct ftrace_event_call *event; int ret = -EINVAL; @@ -77,7 +80,7 @@ int perf_trace_enable(int event_id) list_for_each_entry(event, &ftrace_events, list) { if (event->id == event_id && event->perf_event_enable && try_module_get(event->mod)) { - ret = perf_trace_event_enable(event); + ret = perf_trace_event_enable(event, data); break; } } -- cgit v1.2.3