[PATCH v2 2/6] tracing/boot: Add per-instance tracing_on option support
From: Masami Hiramatsu <mhiramat@kernel.org>
Date: 2020-09-01 07:57:00
Also in:
lkml
Subsystem:
the rest, tracing · Maintainers:
Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Add per-instance tracing_on option, which will be useful with traceon/traceoff event trigger actions. For example, if we disable tracing_on by default and set traceon and traceoff on a pair of events, we can trace functions between the pair of events. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> --- kernel/trace/trace_boot.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index fa0fc08c6ef8..d52d441a17e8 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c@@ -40,6 +40,16 @@ trace_boot_set_instance_options(struct trace_array *tr, struct xbc_node *node) pr_err("Failed to set option: %s\n", buf); } + p = xbc_node_find_value(node, "tracing_on", NULL); + if (p && *p != '\0') { + if (kstrtoul(p, 10, &v)) + pr_err("Failed to set tracing on: %s\n", p); + if (v) + tracer_tracing_on(tr); + else + tracer_tracing_off(tr); + } + p = xbc_node_find_value(node, "trace_clock", NULL); if (p && *p != '\0') { if (tracing_set_clock(tr, p) < 0)