summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
authorVaibhav Nagarnaik <vnagarnaik@google.com>2014-02-13 19:51:48 -0800
committerJiri Slaby <jslaby@suse.cz>2014-03-31 14:22:25 +0200
commitc0316f975b1a29a1161f86d524150f493188e9b2 (patch)
tree8876dd6e837ac6a55dbe24b95b2d29af0cc265c3 /include
parentbf7cda9a0101c4a149aa5846306df9d21dd5cc2b (diff)
tracing: Fix array size mismatch in format string
commit 87291347c49dc40aa339f587b209618201c2e527 upstream. In event format strings, the array size is reported in two locations. One in array subscript and then via the "size:" attribute. The values reported there have a mismatch. For e.g., in sched:sched_switch the prev_comm and next_comm character arrays have subscript values as [32] where as the actual field size is 16. name: sched_switch ID: 301 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1;signed:0; field:int common_pid; offset:4; size:4; signed:1; field:char prev_comm[32]; offset:8; size:16; signed:1; field:pid_t prev_pid; offset:24; size:4; signed:1; field:int prev_prio; offset:28; size:4; signed:1; field:long prev_state; offset:32; size:8; signed:1; field:char next_comm[32]; offset:40; size:16; signed:1; field:pid_t next_pid; offset:56; size:4; signed:1; field:int next_prio; offset:60; size:4; signed:1; After bisection, the following commit was blamed: 92edca0 tracing: Use direct field, type and system names This commit removes the duplication of strings for field->name and field->type assuming that all the strings passed in __trace_define_field() are immutable. This is not true for arrays, where the type string is created in event_storage variable and field->type for all array fields points to event_storage. Use __stringify() to create a string constant for the type string. Also, get rid of event_storage and event_storage_mutex that are not needed anymore. also, an added benefit is that this reduces the overhead of events a bit more: text data bss dec hex filename 8424787 2036472 1302528 11763787 b3804b vmlinux 8420814 2036408 1302528 11759750 b37086 vmlinux.patched Link: http://lkml.kernel.org/r/1392349908-29685-1-git-send-email-vnagarnaik@google.com Cc: Laurent Chavey <chavey@google.com> Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'include')
-rw-r--r--include/linux/ftrace_event.h4
-rw-r--r--include/trace/ftrace.h7
2 files changed, 2 insertions, 9 deletions
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 5eaa746735ff..20aebdbab9a4 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -325,10 +325,6 @@ enum {
FILTER_TRACE_FN,
};
-#define EVENT_STORAGE_SIZE 128
-extern struct mutex event_storage_mutex;
-extern char event_storage[EVENT_STORAGE_SIZE];
-
extern int trace_event_raw_init(struct ftrace_event_call *call);
extern int trace_define_field(struct ftrace_event_call *call, const char *type,
const char *name, int offset, int size,
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 712ea36067ab..645d749d3c9c 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -303,15 +303,12 @@ static struct trace_event_functions ftrace_event_type_funcs_##call = { \
#undef __array
#define __array(type, item, len) \
do { \
- mutex_lock(&event_storage_mutex); \
+ char *type_str = #type"["__stringify(len)"]"; \
BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \
- snprintf(event_storage, sizeof(event_storage), \
- "%s[%d]", #type, len); \
- ret = trace_define_field(event_call, event_storage, #item, \
+ ret = trace_define_field(event_call, type_str, #item, \
offsetof(typeof(field), item), \
sizeof(field.item), \
is_signed_type(type), FILTER_OTHER); \
- mutex_unlock(&event_storage_mutex); \
if (ret) \
return ret; \
} while (0);