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| author |   Masami Hiramatsu <mhiramat@kernel.org> | 2020-01-11 01:06:17 +0900 |
|---|---|---|
| committer |   Steven Rostedt (VMware) <rostedt@goodmis.org> | 2020-01-13 13:19:41 -0500 |
| commit | 9c5b9d3d65e485826fb935453f01171b1a337aa8 (patch) | |
| tree | eb09959ae5da9dd231df0bcfd17a6cbd944f727f /kernel/trace/trace.c | |
| parent | tracing: Add NULL trace-array check in print_synth_event() (diff) | |
| download | linux-dev-9c5b9d3d65e485826fb935453f01171b1a337aa8.tar.xz linux-dev-9c5b9d3d65e485826fb935453f01171b1a337aa8.zip | |
tracing/boot: Add boot-time tracing
Setup tracing options via extra boot config in addition to kernel
command line.
This adds following commands support. These are applied to
the global trace instance.
- ftrace.options = OPT1[,OPT2...]
Enable given ftrace options.
- ftrace.trace_clock = CLOCK
Set given CLOCK to ftrace's trace_clock.
- ftrace.buffer_size = SIZE
Configure ftrace buffer size to SIZE. You can use "KB" or "MB"
for that SIZE.
- ftrace.events = EVENT[, EVENT2...]
Enable given events on boot. You can use a wild card in EVENT.
- ftrace.tracer = TRACER
Set TRACER to current tracer on boot. (e.g. function)
Note that this is NOT replacing the kernel parameters, because
this boot config based setting is later than that. If you want to
trace earlier boot events, you still need kernel parameters.
Link: http://lkml.kernel.org/r/157867237723.17873.17494943526320587488.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index cb850d2c4bfa..6c996d1b1687 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -162,7 +162,7 @@ union trace_eval_map_item { static union trace_eval_map_item *trace_eval_maps; #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ -static int tracing_set_tracer(struct trace_array *tr, const char *buf); +int tracing_set_tracer(struct trace_array *tr, const char *buf); static void ftrace_trace_userstack(struct trace_buffer *buffer, unsigned long flags, int pc); @@ -4747,7 +4747,7 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) return 0; } -static int trace_set_options(struct trace_array *tr, char *option) +int trace_set_options(struct trace_array *tr, char *option) { char *cmp; int neg = 0; @@ -5647,8 +5647,8 @@ static int __tracing_resize_ring_buffer(struct trace_array *tr, return ret; } -static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, - unsigned long size, int cpu_id) +ssize_t tracing_resize_ring_buffer(struct trace_array *tr, + unsigned long size, int cpu_id) { int ret = size; @@ -5727,7 +5727,7 @@ static void add_tracer_options(struct trace_array *tr, struct tracer *t) create_trace_option_files(tr, t); } -static int tracing_set_tracer(struct trace_array *tr, const char *buf) +int tracing_set_tracer(struct trace_array *tr, const char *buf) { struct tracer *t; #ifdef CONFIG_TRACER_MAX_TRACE |