From 9cd2992f2d6c8df54c5b937d5d1f8a23b684cc1d Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Wed, 14 Nov 2018 13:14:58 -0500 Subject: fgraph: Have set_graph_notrace only affect function_graph tracer In order to make the function graph infrastructure more generic, there can not be code specific for the function_graph tracer in the generic code. This includes the set_graph_notrace logic, that stops all graph calls when a function in the set_graph_notrace is hit. By using the trace_recursion mask, we can use a bit in the current task_struct to implement the notrace code, and move the logic out of fgraph.c and into trace_functions_graph.c and keeps it affecting only the tracer and not all call graph callbacks. Acked-by: Namhyung Kim Reviewed-by: Joel Fernandes (Google) Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_functions_graph.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'kernel/trace/trace_functions_graph.c') diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index b846d82c2f95..ecf543df943b 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -188,6 +188,18 @@ int trace_graph_entry(struct ftrace_graph_ent *trace) int cpu; int pc; + if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT)) + return 0; + + if (ftrace_graph_notrace_addr(trace->func)) { + trace_recursion_set(TRACE_GRAPH_NOTRACE_BIT); + /* + * Need to return 1 to have the return called + * that will clear the NOTRACE bit. + */ + return 1; + } + if (!ftrace_trace_task(tr)) return 0; @@ -290,6 +302,11 @@ void trace_graph_return(struct ftrace_graph_ret *trace) ftrace_graph_addr_finish(trace); + if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT)) { + trace_recursion_clear(TRACE_GRAPH_NOTRACE_BIT); + return; + } + local_irq_save(flags); cpu = raw_smp_processor_id(); data = per_cpu_ptr(tr->trace_buffer.data, cpu); @@ -315,6 +332,11 @@ static void trace_graph_thresh_return(struct ftrace_graph_ret *trace) { ftrace_graph_addr_finish(trace); + if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT)) { + trace_recursion_clear(TRACE_GRAPH_NOTRACE_BIT); + return; + } + if (tracing_thresh && (trace->rettime - trace->calltime < tracing_thresh)) return; -- cgit v1.2.3