git-commit-vandalism/trace.h
Nguyễn Thái Ngọc Duy c46c406ae1 trace.h: support nested performance tracing
Performance measurements are listed right now as a flat list, which is
fine when we measure big blocks. But when we start adding more and
more measurements, some of them could be just part of a bigger
measurement and a flat list gives a wrong impression that they are
executed at the same level instead of nested.

Add trace_performance_enter() and trace_performance_leave() to allow
indent these nested measurements. For now it does not help much
because the only nested thing is (lazy) name hash initialization
(e.g. called in diff-index from "git status"). This will help more
because I'm going to add some more tracing that's actually nested.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-18 09:47:46 -07:00

156 lines
4.9 KiB
C

#ifndef TRACE_H
#define TRACE_H
#include "git-compat-util.h"
#include "strbuf.h"
struct trace_key {
const char * const key;
int fd;
unsigned int initialized : 1;
unsigned int need_close : 1;
};
extern struct trace_key trace_default_key;
#define TRACE_KEY_INIT(name) { "GIT_TRACE_" #name, 0, 0, 0 }
extern struct trace_key trace_perf_key;
extern struct trace_key trace_setup_key;
extern void trace_repo_setup(const char *prefix);
extern int trace_want(struct trace_key *key);
extern void trace_disable(struct trace_key *key);
extern uint64_t getnanotime(void);
extern void trace_command_performance(const char **argv);
extern void trace_verbatim(struct trace_key *key, const void *buf, unsigned len);
uint64_t trace_performance_enter(void);
#ifndef HAVE_VARIADIC_MACROS
__attribute__((format (printf, 1, 2)))
extern void trace_printf(const char *format, ...);
__attribute__((format (printf, 2, 3)))
extern void trace_printf_key(struct trace_key *key, const char *format, ...);
__attribute__((format (printf, 2, 3)))
extern void trace_argv_printf(const char **argv, const char *format, ...);
extern void trace_strbuf(struct trace_key *key, const struct strbuf *data);
/* Prints elapsed time (in nanoseconds) if GIT_TRACE_PERFORMANCE is enabled. */
__attribute__((format (printf, 2, 3)))
extern void trace_performance(uint64_t nanos, const char *format, ...);
/* Prints elapsed time since 'start' if GIT_TRACE_PERFORMANCE is enabled. */
__attribute__((format (printf, 2, 3)))
extern void trace_performance_since(uint64_t start, const char *format, ...);
__attribute__((format (printf, 1, 2)))
void trace_performance_leave(const char *format, ...);
#else
/*
* Macros to add file:line - see above for C-style declarations of how these
* should be used.
*/
/*
* TRACE_CONTEXT may be set to __FUNCTION__ if the compiler supports it. The
* default is __FILE__, as it is consistent with assert(), and static function
* names are not necessarily unique.
*
* __FILE__ ":" __FUNCTION__ doesn't work with GNUC, as __FILE__ is supplied
* by the preprocessor as a string literal, and __FUNCTION__ is filled in by
* the compiler as a string constant.
*/
#ifndef TRACE_CONTEXT
# define TRACE_CONTEXT __FILE__
#endif
/*
* Note: with C99 variadic macros, __VA_ARGS__ must include the last fixed
* parameter ('format' in this case). Otherwise, a call without variable
* arguments will have a surplus ','. E.g.:
*
* #define foo(format, ...) bar(format, __VA_ARGS__)
* foo("test");
*
* will expand to
*
* bar("test",);
*
* which is invalid (note the ',)'). With GNUC, '##__VA_ARGS__' drops the
* comma, but this is non-standard.
*/
#define trace_printf_key(key, ...) \
do { \
if (trace_pass_fl(key)) \
trace_printf_key_fl(TRACE_CONTEXT, __LINE__, key, \
__VA_ARGS__); \
} while (0)
#define trace_printf(...) trace_printf_key(&trace_default_key, __VA_ARGS__)
#define trace_argv_printf(argv, ...) \
do { \
if (trace_pass_fl(&trace_default_key)) \
trace_argv_printf_fl(TRACE_CONTEXT, __LINE__, \
argv, __VA_ARGS__); \
} while (0)
#define trace_strbuf(key, data) \
do { \
if (trace_pass_fl(key)) \
trace_strbuf_fl(TRACE_CONTEXT, __LINE__, key, data);\
} while (0)
#define trace_performance(nanos, ...) \
do { \
if (trace_pass_fl(&trace_perf_key)) \
trace_performance_fl(TRACE_CONTEXT, __LINE__, nanos,\
__VA_ARGS__); \
} while (0)
#define trace_performance_since(start, ...) \
do { \
if (trace_pass_fl(&trace_perf_key)) \
trace_performance_fl(TRACE_CONTEXT, __LINE__, \
getnanotime() - (start), \
__VA_ARGS__); \
} while (0)
#define trace_performance_leave(...) \
do { \
if (trace_pass_fl(&trace_perf_key)) \
trace_performance_leave_fl(TRACE_CONTEXT, __LINE__, \
getnanotime(), \
__VA_ARGS__); \
} while (0)
/* backend functions, use non-*fl macros instead */
__attribute__((format (printf, 4, 5)))
extern void trace_printf_key_fl(const char *file, int line, struct trace_key *key,
const char *format, ...);
__attribute__((format (printf, 4, 5)))
extern void trace_argv_printf_fl(const char *file, int line, const char **argv,
const char *format, ...);
extern void trace_strbuf_fl(const char *file, int line, struct trace_key *key,
const struct strbuf *data);
__attribute__((format (printf, 4, 5)))
extern void trace_performance_fl(const char *file, int line,
uint64_t nanos, const char *fmt, ...);
__attribute__((format (printf, 4, 5)))
extern void trace_performance_leave_fl(const char *file, int line,
uint64_t nanos, const char *fmt, ...);
static inline int trace_pass_fl(struct trace_key *key)
{
return key->fd || !key->initialized;
}
#endif /* HAVE_VARIADIC_MACROS */
#endif /* TRACE_H */