From fe1efe9252f938f0cc624e4ac817c27bcaef6ed0 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Sat, 11 Jan 2020 01:07:28 +0900 Subject: [PATCH] tracing/boot: Add function tracer filter options Add below function-tracer filter options to boot-time tracing. - ftrace.[instance.INSTANCE.]ftrace.filters This will take an array of tracing function filter rules - ftrace.[instance.INSTANCE.]ftrace.notraces This will take an array of NON-tracing function filter rules Link: http://lkml.kernel.org/r/157867244841.17873.10933616628243103561.stgit@devnote2 Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_boot.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 81d923c..fa9603d 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -244,11 +244,51 @@ trace_boot_init_events(struct trace_array *tr, struct xbc_node *node) #define trace_boot_init_events(tr, node) do {} while (0) #endif +#ifdef CONFIG_DYNAMIC_FTRACE +extern bool ftrace_filter_param __initdata; +extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, + int len, int reset); +extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, + int len, int reset); +static void __init +trace_boot_set_ftrace_filter(struct trace_array *tr, struct xbc_node *node) +{ + struct xbc_node *anode; + const char *p; + char *q; + + xbc_node_for_each_array_value(node, "ftrace.filters", anode, p) { + q = kstrdup(p, GFP_KERNEL); + if (!q) + return; + if (ftrace_set_filter(tr->ops, q, strlen(q), 0) < 0) + pr_err("Failed to add %s to ftrace filter\n", p); + else + ftrace_filter_param = true; + kfree(q); + } + xbc_node_for_each_array_value(node, "ftrace.notraces", anode, p) { + q = kstrdup(p, GFP_KERNEL); + if (!q) + return; + if (ftrace_set_notrace(tr->ops, q, strlen(q), 0) < 0) + pr_err("Failed to add %s to ftrace filter\n", p); + else + ftrace_filter_param = true; + kfree(q); + } +} +#else +#define trace_boot_set_ftrace_filter(tr, node) do {} while (0) +#endif + static void __init trace_boot_enable_tracer(struct trace_array *tr, struct xbc_node *node) { const char *p; + trace_boot_set_ftrace_filter(tr, node); + p = xbc_node_find_value(node, "tracer", NULL); if (p && *p != '\0') { if (tracing_set_tracer(tr, p) < 0) -- 2.7.4