Commit ac483c44 authored by Jiri Olsa's avatar Jiri Olsa Committed by Steven Rostedt
Browse files

ftrace: Change filter/notrace set functions to return exit code 

Currently the ftrace_set_filter and ftrace_set_notrace functions
do not return any return code. So there's no way for ftrace_ops
user to tell wether the filter was correctly applied.

The set_ftrace_filter interface returns error in case the filter
did not match:

  # echo krava > set_ftrace_filter
  bash: echo: write error: Invalid argument

Changing both ftrace_set_filter and ftrace_set_notrace functions
to return zero if the filter was applied correctly or -E* values
in case of error.

Link: http://lkml.kernel.org/r/1325495060-6402-2-git-send-email-jolsa@redhat.com



Acked-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: default avatarJiri Olsa <jolsa@redhat.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 623ec991

include/linux/ftrace.h

+2 −2
Original line number Diff line number Diff line
@@ -178,9 +178,9 @@ struct dyn_ftrace { 
};



int ftrace_force_update(void);

void ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,

int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,

		       int len, int reset);

void ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,

int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,

			int len, int reset);

void ftrace_set_global_filter(unsigned char *buf, int len, int reset);

void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);

kernel/trace/ftrace.c

+9 −6
Original line number Diff line number Diff line
@@ -3146,8 +3146,10 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, 
	mutex_lock(&ftrace_regex_lock);

	if (reset)

		ftrace_filter_reset(hash);

	if (buf)

		ftrace_match_records(hash, buf, len);

	if (buf && !ftrace_match_records(hash, buf, len)) {

		ret = -EINVAL;

		goto out_regex_unlock;

	}



	mutex_lock(&ftrace_lock);

	ret = ftrace_hash_move(ops, enable, orig_hash, hash);
@@ -3157,6 +3159,7 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, 


	mutex_unlock(&ftrace_lock);



 out_regex_unlock:

	mutex_unlock(&ftrace_regex_lock);



	free_ftrace_hash(hash);
@@ -3173,10 +3176,10 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, 
 * Filters denote which functions should be enabled when tracing is enabled.

 * If @buf is NULL and reset is set, all functions will be enabled for tracing.

 */

void ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,

int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,

		       int len, int reset)

{

	ftrace_set_regex(ops, buf, len, reset, 1);

	return ftrace_set_regex(ops, buf, len, reset, 1);

}

EXPORT_SYMBOL_GPL(ftrace_set_filter);
@@ -3191,10 +3194,10 @@ EXPORT_SYMBOL_GPL(ftrace_set_filter); 
 * is enabled. If @buf is NULL and reset is set, all functions will be enabled

 * for tracing.

 */

void ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,

int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,

			int len, int reset)

{

	ftrace_set_regex(ops, buf, len, reset, 0);

	return ftrace_set_regex(ops, buf, len, reset, 0);

}

EXPORT_SYMBOL_GPL(ftrace_set_notrace);

/**

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