12473965c3
The next patch tries to avoid the costly perf_trace_buf_* calls when possible but there is a problem. We can only do this if __task == NULL, perf_tp_event(task != NULL) has the additional code for this case. Unfortunately, TP_perf_assign/__perf_xxx which changes the default values of __count/__task variables for perf_trace_buf_submit() is called "too late", after we already did perf_trace_buf_prepare(), and the optimization above can't work. So this patch simply embeds __perf_xxx() into TP_ARGS(), this way DECLARE_EVENT_CLASS() can use the result of assignments hidden in "args" right after ftrace_get_offsets_##call() which is mostly trivial. This allows us to have the fast-path "__task != NULL" check at the start, see the next patch. Link: http://lkml.kernel.org/r/20130806160844.GA2739@redhat.com Tested-by: David Ahern <dsahern@gmail.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> |
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| .. | ||
| events | ||
| define_trace.h | ||
| ftrace.h | ||
| syscall.h | ||