From 7fa8b7171a638ad896acabd9a17183b75b70aeb4 Mon Sep 17 00:00:00 2001 From: Joel Fernandes Date: Fri, 17 Jun 2016 22:44:54 -0700 Subject: [PATCH] tracing/function_graph: Fix filters for function_graph threshold Function graph tracer currently ignores filters if tracing_thresh is set. For example, even if set_ftrace_pid is set, then its ignored if tracing_thresh set, resulting in all processes being traced. To fix this, we reuse the same entry function as when tracing_thresh is not set and do everything as in the regular case except for writing the function entry to the ring buffer. Link: http://lkml.kernel.org/r/1466228694-2677-1-git-send-email-agnel.joel@gmail.com Cc: Frederic Weisbecker Cc: Ingo Molnar Signed-off-by: Joel Fernandes Signed-off-by: Steven Rostedt --- kernel/trace/trace_functions_graph.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 67cce7896aeb..7363ccf79512 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -338,6 +338,13 @@ int trace_graph_entry(struct ftrace_graph_ent *trace) if (ftrace_graph_notrace_addr(trace->func)) return 1; + /* + * Stop here if tracing_threshold is set. We only write function return + * events to the ring buffer. + */ + if (tracing_thresh) + return 1; + local_irq_save(flags); cpu = raw_smp_processor_id(); data = per_cpu_ptr(tr->trace_buffer.data, cpu); @@ -355,14 +362,6 @@ int trace_graph_entry(struct ftrace_graph_ent *trace) return ret; } -static int trace_graph_thresh_entry(struct ftrace_graph_ent *trace) -{ - if (tracing_thresh) - return 1; - else - return trace_graph_entry(trace); -} - static void __trace_graph_function(struct trace_array *tr, unsigned long ip, unsigned long flags, int pc) @@ -457,7 +456,7 @@ static int graph_trace_init(struct trace_array *tr) set_graph_array(tr); if (tracing_thresh) ret = register_ftrace_graph(&trace_graph_thresh_return, - &trace_graph_thresh_entry); + &trace_graph_entry); else ret = register_ftrace_graph(&trace_graph_return, &trace_graph_entry);