linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Masami Hiramatsu <mhiramat@kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>,
	Frank Rowand <frowand.list@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>,
	Namhyung Kim <namhyung@kernel.org>, Tim Bird <Tim.Bird@sony.com>,
	Jiri Olsa <jolsa@redhat.com>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Tom Zanussi <tom.zanussi@linux.intel.com>,
	Rob Herring <robh+dt@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Alexey Dobriyan <adobriyan@gmail.com>,
	Jonathan Corbet <corbet@lwn.net>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [RFC PATCH v3 12/19] tracing/boot: Add per-event settings
Date: Mon, 26 Aug 2019 12:18:00 +0900	[thread overview]
Message-ID: <156678948034.21459.12734081118923661873.stgit@devnote2> (raw)
In-Reply-To: <156678933823.21459.4100380582025186209.stgit@devnote2>

Add per-event settings for boottime tracing. User can set filter,
actions and enable on each event on boot. The event entries are
under ftrace.event.GROUP.EVENT node (note that the option key
includes event's group name and event name.) This supports below
commands.

 - ftrace.event.GROUP.EVENT.enable;
   Enables GROUP:EVENT tracing.

 - ftrace.event.GROUP.EVENT.filter = FILTER;
   Set FILTER rule to the GROUP:EVENT.

 - ftrace.event.GROUP.EVENT.actions = ACTION[, ACTION2...];
   Set ACTIONs to the GROUP:EVENT.

For example,

  ftrace.event.sched.sched_process_exec {
                filter = "pid < 128";
		enable;
  }

this will enable tracing "sched:sched_process_exec" event
with "pid < 128" filter.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
 kernel/trace/trace_boot.c           |   60 +++++++++++++++++++++++++++++++++++
 kernel/trace/trace_events_trigger.c |    2 +
 2 files changed, 61 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index cc5e81368065..cfd628c16761 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -80,6 +80,7 @@ trace_boot_set_ftrace_options(struct trace_array *tr, struct skc_node *node)
 
 #ifdef CONFIG_EVENT_TRACING
 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
+extern int trigger_process_regex(struct trace_event_file *file, char *buff);
 
 static void __init
 trace_boot_enable_events(struct trace_array *tr, struct skc_node *node)
@@ -98,8 +99,66 @@ trace_boot_enable_events(struct trace_array *tr, struct skc_node *node)
 			pr_err("Failed to enable event: %s\n", p);
 	}
 }
+
+static void __init
+trace_boot_init_one_event(struct trace_array *tr, struct skc_node *gnode,
+			  struct skc_node *enode)
+{
+	struct trace_event_file *file;
+	struct skc_node *anode;
+	char buf[MAX_BUF_LEN];
+	const char *p, *group, *event;
+
+	group = skc_node_get_data(gnode);
+	event = skc_node_get_data(enode);
+
+	mutex_lock(&event_mutex);
+	file = find_event_file(tr, group, event);
+	if (!file) {
+		pr_err("Failed to find event: %s:%s\n", group, event);
+		goto out;
+	}
+
+	p = skc_node_find_value(enode, "filter", NULL);
+	if (p && *p != '\0') {
+		if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
+			pr_err("filter string is too long: %s\n", p);
+		else if (apply_event_filter(file, buf) < 0)
+			pr_err("Failed to apply filter: %s\n", buf);
+	}
+
+	skc_node_for_each_array_value(enode, "actions", anode, p) {
+		if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
+			pr_err("action string is too long: %s\n", p);
+		else if (trigger_process_regex(file, buf) < 0)
+			pr_err("Failed to apply an action: %s\n", buf);
+	}
+
+	if (skc_node_find_value(enode, "enable", NULL)) {
+		if (trace_event_enable_disable(file, 1, 0) < 0)
+			pr_err("Failed to enable event node: %s:%s\n",
+				group, event);
+	}
+out:
+	mutex_unlock(&event_mutex);
+}
+
+static void __init
+trace_boot_init_events(struct trace_array *tr, struct skc_node *node)
+{
+	struct skc_node *gnode, *enode;
+
+	node = skc_node_find_child(node, "event");
+	if (!node)
+		return;
+	/* per-event key starts with "event.GROUP.EVENT" */
+	skc_node_for_each_child(node, gnode)
+		skc_node_for_each_child(gnode, enode)
+			trace_boot_init_one_event(tr, gnode, enode);
+}
 #else
 #define trace_boot_enable_events(tr, node) do {} while (0)
+#define trace_boot_init_events(tr, node) do {} while (0)
 #endif
 
 static void __init
@@ -128,6 +187,7 @@ static int __init trace_boot_init(void)
 		return 0;
 
 	trace_boot_set_ftrace_options(tr, trace_node);
+	trace_boot_init_events(tr, trace_node);
 	trace_boot_enable_events(tr, trace_node);
 	trace_boot_enable_tracer(tr, trace_node);
 
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 2a2912cb4533..74a19c18219f 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -208,7 +208,7 @@ static int event_trigger_regex_open(struct inode *inode, struct file *file)
 	return ret;
 }
 
-static int trigger_process_regex(struct trace_event_file *file, char *buff)
+int trigger_process_regex(struct trace_event_file *file, char *buff)
 {
 	char *command, *next = buff;
 	struct event_command *p;


  parent reply	other threads:[~2019-08-26  3:18 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-26  3:15 [RFC PATCH v3 00/19] tracing: skc: Boot-time tracing and Supplemental Kernel Cmdline Masami Hiramatsu
2019-08-26  3:15 ` [RFC PATCH v3 01/19] skc: Add supplemental kernel cmdline support Masami Hiramatsu
2019-08-26 13:27   ` Rob Herring
2019-08-27  2:37     ` Masami Hiramatsu
2019-08-26  3:16 ` [RFC PATCH v3 02/19] skc: Add /proc/sup_cmdline to show SKC key-value list Masami Hiramatsu
2019-08-26  3:16 ` [RFC PATCH v3 03/19] skc: Add a boot setup routine from cmdline Masami Hiramatsu
2019-08-26  3:16 ` [RFC PATCH v3 04/19] Documentation: skc: Add a doc for supplemental kernel cmdline Masami Hiramatsu
2019-08-26  3:16 ` [RFC PATCH v3 05/19] tracing: Apply soft-disabled and filter to tracepoints printk Masami Hiramatsu
2019-08-26  3:16 ` [RFC PATCH v3 06/19] tracing: kprobes: Output kprobe event to printk buffer Masami Hiramatsu
2019-08-26  3:17 ` [RFC PATCH v3 07/19] tracing: Expose EXPORT_SYMBOL_GPL symbol Masami Hiramatsu
2019-08-26  3:17 ` [RFC PATCH v3 08/19] tracing: kprobes: Register to dynevent earlier stage Masami Hiramatsu
2019-08-26  3:17 ` [RFC PATCH v3 09/19] tracing: Accept different type for synthetic event fields Masami Hiramatsu
2019-08-26  3:17 ` [RFC PATCH v3 10/19] tracing: Add NULL trace-array check in print_synth_event() Masami Hiramatsu
2019-08-26  3:17 ` [RFC PATCH v3 11/19] tracing/boot: Add boot-time tracing by supplemental kernel cmdline Masami Hiramatsu
2019-08-26  3:18 ` Masami Hiramatsu [this message]
2019-08-26  3:18 ` [RFC PATCH v3 13/19] tracing/boot Add kprobe event support Masami Hiramatsu
2019-08-26  3:18 ` [RFC PATCH v3 14/19] tracing/boot: Add synthetic " Masami Hiramatsu
2019-08-26  3:18 ` [RFC PATCH v3 15/19] tracing/boot: Add instance node support Masami Hiramatsu
2019-08-26  3:18 ` [RFC PATCH v3 16/19] tracing/boot: Add cpu_mask option support Masami Hiramatsu
2019-08-26  3:18 ` [RFC PATCH v3 17/19] tracing/boot: Add function tracer filter options Masami Hiramatsu
2019-08-26  3:19 ` [RFC PATCH v3 18/19] tracing/boot: Add function-graph tracer options Masami Hiramatsu
2019-08-26  3:19 ` [RFC PATCH v3 19/19] Documentation: tracing: Add boot-time tracing document Masami Hiramatsu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=156678948034.21459.12734081118923661873.stgit@devnote2 \
    --to=mhiramat@kernel.org \
    --cc=Tim.Bird@sony.com \
    --cc=acme@kernel.org \
    --cc=adobriyan@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=corbet@lwn.net \
    --cc=frowand.list@gmail.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=jolsa@redhat.com \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=namhyung@kernel.org \
    --cc=robh+dt@kernel.org \
    --cc=rostedt@goodmis.org \
    --cc=tglx@linutronix.de \
    --cc=tom.zanussi@linux.intel.com \
    --cc=torvalds@linux-foundation.org \
    --subject='Re: [RFC PATCH v3 12/19] tracing/boot: Add per-event settings' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).