[thirdparty/git.git] / trace2 / tr2_tls.h

#ifndef TR2_TLS_H
#define TR2_TLS_H

#include "strbuf.h"

/*
 * Notice: the term "TLS" refers to "thread-local storage" in the
 * Trace2 source files.  This usage is borrowed from GCC and Windows.
 * There is NO relation to "transport layer security".
 */

/*
 * Arbitry limit for thread names for column alignment.
 */
#define TR2_MAX_THREAD_NAME (24)

struct tr2tls_thread_ctx {
	struct strbuf thread_name;
	uint64_t *array_us_start;
	size_t alloc;
	size_t nr_open_regions; /* plays role of "nr" in ALLOC_GROW */
	int thread_id;
};

/*
 * Create thread-local storage for the current thread.
 *
 * We assume the first thread is "main".  Other threads are given
 * non-zero thread-ids to help distinguish messages from concurrent
 * threads.
 *
 * Truncate the thread name if necessary to help with column alignment
 * in printf-style messages.
 *
 * In this and all following functions the term "self" refers to the
 * current thread.
 */
struct tr2tls_thread_ctx *tr2tls_create_self(const char *thread_base_name,
					     uint64_t us_thread_start);

/*
 * Get the thread-local storage pointer of the current thread.
 */
struct tr2tls_thread_ctx *tr2tls_get_self(void);

/*
 * return true if the current thread is the main thread.
 */
int tr2tls_is_main_thread(void);

/*
 * Free the current thread's thread-local storage.
 */
void tr2tls_unset_self(void);

/*
 * Begin a new nested region and remember the start time.
 */
void tr2tls_push_self(uint64_t us_now);

/*
 * End the innermost nested region.
 */
void tr2tls_pop_self(void);

/*
 * Pop any extra (above the first) open regions on the current
 * thread and discard.  During a thread-exit, we should only
 * have region[0] that was pushed in trace2_thread_start() if
 * the thread exits normally.
 */
void tr2tls_pop_unwind_self(void);

/*
 * Compute the elapsed time since the innermost region in the
 * current thread started and the given time (usually now).
 */
uint64_t tr2tls_region_elasped_self(uint64_t us);

/*
 * Compute the elapsed time since the main thread started
 * and the given time (usually now).  This is assumed to
 * be the absolute run time of the process.
 */
uint64_t tr2tls_absolute_elapsed(uint64_t us);

/*
 * Initialize thread-local storage for Trace2.
 */
void tr2tls_init(void);

/*
 * Free all Trace2 thread-local storage resources.
 */
void tr2tls_release(void);

/*
 * Protected increment of an integer.
 */
int tr2tls_locked_increment(int *p);

/*
 * Capture the process start time and do nothing else.
 */
void tr2tls_start_process_clock(void);

#endif /* TR2_TLS_H */
Commit	Line	Data
ee4512ed JH	1	#ifndef TR2_TLS_H
	2	#define TR2_TLS_H
	3
	4	#include "strbuf.h"
	5
5bbb9251 JH	6	/*
	7	* Notice: the term "TLS" refers to "thread-local storage" in the
	8	* Trace2 source files. This usage is borrowed from GCC and Windows.
	9	* There is NO relation to "transport layer security".
	10	*/
	11
ee4512ed JH	12	/*
	13	* Arbitry limit for thread names for column alignment.
	14	*/
	15	#define TR2_MAX_THREAD_NAME (24)
	16
	17	struct tr2tls_thread_ctx {
	18	struct strbuf thread_name;
	19	uint64_t *array_us_start;
545ddca0 JH	20	size_t alloc;
545ddca0 JH	21	size_t nr_open_regions; /* plays role of "nr" in ALLOC_GROW */
ee4512ed JH	22	int thread_id;
	23	};
	24
	25	/*
5bbb9251	26	* Create thread-local storage for the current thread.
ee4512ed JH	27	*
	28	* We assume the first thread is "main". Other threads are given
	29	* non-zero thread-ids to help distinguish messages from concurrent
	30	* threads.
	31	*
	32	* Truncate the thread name if necessary to help with column alignment
	33	* in printf-style messages.
	34	*
	35	* In this and all following functions the term "self" refers to the
	36	* current thread.
	37	*/
a70839cf	38	struct tr2tls_thread_ctx tr2tls_create_self(const char thread_base_name,
a0897249	39	uint64_t us_thread_start);
ee4512ed JH	40
ee4512ed JH	41	/*
5bbb9251	42	* Get the thread-local storage pointer of the current thread.
ee4512ed JH	43	*/
	44	struct tr2tls_thread_ctx *tr2tls_get_self(void);
	45
	46	/*
	47	* return true if the current thread is the main thread.
	48	*/
	49	int tr2tls_is_main_thread(void);
	50
	51	/*
5bbb9251	52	* Free the current thread's thread-local storage.
ee4512ed JH	53	*/
	54	void tr2tls_unset_self(void);
	55
	56	/*
	57	* Begin a new nested region and remember the start time.
	58	*/
	59	void tr2tls_push_self(uint64_t us_now);
	60
	61	/*
	62	* End the innermost nested region.
	63	*/
	64	void tr2tls_pop_self(void);
	65
	66	/*
	67	* Pop any extra (above the first) open regions on the current
	68	* thread and discard. During a thread-exit, we should only
	69	* have region[0] that was pushed in trace2_thread_start() if
	70	* the thread exits normally.
	71	*/
	72	void tr2tls_pop_unwind_self(void);
	73
	74	/*
	75	* Compute the elapsed time since the innermost region in the
	76	* current thread started and the given time (usually now).
	77	*/
	78	uint64_t tr2tls_region_elasped_self(uint64_t us);
	79
	80	/*
	81	* Compute the elapsed time since the main thread started
	82	* and the given time (usually now). This is assumed to
	83	* be the absolute run time of the process.
	84	*/
	85	uint64_t tr2tls_absolute_elapsed(uint64_t us);
	86
	87	/*
5bbb9251	88	* Initialize thread-local storage for Trace2.
ee4512ed JH	89	*/
	90	void tr2tls_init(void);
	91
	92	/*
5bbb9251	93	* Free all Trace2 thread-local storage resources.
ee4512ed JH	94	*/
	95	void tr2tls_release(void);
	96
	97	/*
	98	* Protected increment of an integer.
	99	*/
	100	int tr2tls_locked_increment(int *p);
	101
a0897249 JH	102	/*
	103	* Capture the process start time and do nothing else.
	104	*/
	105	void tr2tls_start_process_clock(void);
	106
ee4512ed	107	#endif /* TR2_TLS_H */