From: Masami Hiramatsu mhiramat@kernel.org

Fix synthetic event to accept unsigned modifier for its field type correctly.

Currently, synthetic_events interface returns error for "unsigned" modifiers as below;

# echo "myevent unsigned long var" >> synthetic_events sh: write error: Invalid argument

This is because argv_split() breaks "unsigned long" into "unsigned" and "long", but parse_synth_field() doesn't expected it.

With this fix, synthetic_events can handle the "unsigned long" correctly like as below;

# echo "myevent unsigned long var" >> synthetic_events # cat synthetic_events myevent unsigned long var

Link: http://lkml.kernel.org/r/153986832571.18251.8448135724590496531.stgit@devbox

Cc: Shuah Khan shuah@kernel.org Cc: Tom Zanussi tom.zanussi@linux.intel.com Cc: stable@vger.kernel.org Fixes: commit 4b147936fa50 ("tracing: Add support for 'synthetic' events") Signed-off-by: Masami Hiramatsu mhiramat@kernel.org Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org --- kernel/trace/trace_events_hist.c | 30 ++++++++++++++++++++++++------ 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 85f6b01431c7..6ff83941065a 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -738,16 +738,30 @@ static void free_synth_field(struct synth_field *field) kfree(field); }

-static struct synth_field *parse_synth_field(char *field_type, - char *field_name) +static struct synth_field *parse_synth_field(int argc, char **argv, + int *consumed) { struct synth_field *field; + const char *prefix = NULL; + char *field_type = argv[0], *field_name; int len, ret = 0; char *array;

if (field_type[0] == ';') field_type++;

+ if (!strcmp(field_type, "unsigned")) { + if (argc < 3) + return ERR_PTR(-EINVAL); + prefix = "unsigned "; + field_type = argv[1]; + field_name = argv[2]; + *consumed = 3; + } else { + field_name = argv[1]; + *consumed = 2; + } + len = strlen(field_name); if (field_name[len - 1] == ';') field_name[len - 1] = '\0'; @@ -760,11 +774,15 @@ static struct synth_field *parse_synth_field(char *field_type, array = strchr(field_name, '['); if (array) len += strlen(array); + if (prefix) + len += strlen(prefix); field->type = kzalloc(len, GFP_KERNEL); if (!field->type) { ret = -ENOMEM; goto free; } + if (prefix) + strcat(field->type, prefix); strcat(field->type, field_type); if (array) { strcat(field->type, array); @@ -1009,7 +1027,7 @@ static int create_synth_event(int argc, char **argv) struct synth_field *field, *fields[SYNTH_FIELDS_MAX]; struct synth_event *event = NULL; bool delete_event = false; - int i, n_fields = 0, ret = 0; + int i, consumed = 0, n_fields = 0, ret = 0; char *name;

mutex_lock(&synth_event_mutex); @@ -1061,13 +1079,13 @@ static int create_synth_event(int argc, char **argv) goto err; }

- field = parse_synth_field(argv[i], argv[i + 1]); + field = parse_synth_field(argc - i, &argv[i], &consumed); if (IS_ERR(field)) { ret = PTR_ERR(field); goto err; } - fields[n_fields] = field; - i++; n_fields++; + fields[n_fields++] = field; + i += consumed - 1; }

if (i < argc) {