Commit 31696198 authored by Tom Zanussi's avatar Tom Zanussi Committed by Steven Rostedt
Browse files

tracing: Add hist trigger 'syscall' modifier 

Allow users to have syscall id fields displayed as syscall names in
the output by appending '.syscall' to field names:

   # echo hist:keys=aaa.syscall ... \
              [ if filter] > event/trigger

Link: http://lkml.kernel.org/r/2bab1e59933d76a14b545bd2e02f80b8b08ac4d3.1457029949.git.tom.zanussi@linux.intel.com



Signed-off-by: default avatarTom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: default avatarMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: default avatarNamhyung Kim <namhyung@kernel.org>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 6b4827ad

kernel/trace/trace.c

+2 −1
Original line number Diff line number Diff line
@@ -3858,7 +3858,8 @@ static const char readme_msg[] = 
	"\t            .hex        display a number as a hex value\n"

	"\t            .sym        display an address as a symbol\n"

	"\t            .sym-offset display an address as a symbol and offset\n"

	"\t            .execname   display a common_pid as a program name\n\n"

	"\t            .execname   display a common_pid as a program name\n"

	"\t            .syscall    display a syscall id as a syscall name\n\n"

	"\t    The 'pause' parameter can be used to pause an existing hist\n"

	"\t    trigger or to start a hist trigger but not log any events\n"

	"\t    until told to do so.  'continue' can be used to start or\n"

kernel/trace/trace_events_hist.c

+15 −0
Original line number Diff line number Diff line
@@ -84,6 +84,7 @@ enum hist_field_flags { 
	HIST_FIELD_FL_SYM		= 16,

	HIST_FIELD_FL_SYM_OFFSET	= 32,

	HIST_FIELD_FL_EXECNAME		= 64,

	HIST_FIELD_FL_SYSCALL		= 128,

};



struct hist_trigger_attrs {
@@ -474,6 +475,8 @@ static int create_key_field(struct hist_trigger_data *hist_data, 
		else if ((strcmp(field_str, "execname") == 0) &&

			 (strcmp(field_name, "common_pid") == 0))

			flags |= HIST_FIELD_FL_EXECNAME;

		else if (strcmp(field_str, "syscall") == 0)

			flags |= HIST_FIELD_FL_SYSCALL;

		else {

			ret = -EINVAL;

			goto out;
@@ -854,6 +857,16 @@ hist_trigger_entry_print(struct seq_file *m, 
			uval = *(u64 *)(key + key_field->offset);

			seq_printf(m, "%s: %-16s[%10llu]",

				   key_field->field->name, comm, uval);

		} else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {

			const char *syscall_name;



			uval = *(u64 *)(key + key_field->offset);

			syscall_name = get_syscall_name(uval);

			if (!syscall_name)

				syscall_name = "unknown_syscall";



			seq_printf(m, "%s: %-30s[%3llu]",

				   key_field->field->name, syscall_name, uval);

		} else if (key_field->flags & HIST_FIELD_FL_STRING) {

			seq_printf(m, "%s: %-50s", key_field->field->name,

				   (char *)(key + key_field->offset));
@@ -975,6 +988,8 @@ static const char *get_hist_field_flags(struct hist_field *hist_field) 
		flags_str = "sym-offset";

	else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)

		flags_str = "execname";

	else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)

		flags_str = "syscall";



	return flags_str;

}

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