jemalloc/include/jemalloc/internal/prof_externs.h

#ifndef JEMALLOC_INTERNAL_PROF_EXTERNS_H
#define JEMALLOC_INTERNAL_PROF_EXTERNS_H

#include "jemalloc/internal/jemalloc_preamble.h"
#include "jemalloc/internal/base.h"
#include "jemalloc/internal/mutex.h"
#include "jemalloc/internal/prof_hook.h"
#include "jemalloc/internal/thread_event_registry.h"

extern bool     opt_prof;
extern bool     opt_prof_active;
extern bool     opt_prof_thread_active_init;
extern unsigned opt_prof_bt_max;
extern size_t   opt_lg_prof_sample; /* Mean bytes between samples. */
extern size_t
    opt_experimental_lg_prof_threshold; /* Mean bytes between thresholds. */
extern ssize_t opt_lg_prof_interval;    /* lg(prof_interval). */
extern bool    opt_prof_gdump;          /* High-water memory dumping. */
extern bool    opt_prof_final;          /* Final profile dumping. */
extern bool    opt_prof_leak;           /* Dump leak summary at exit. */
extern bool    opt_prof_leak_error; /* Exit with error code if memory leaked */
extern bool    opt_prof_accum;      /* Report cumulative bytes. */
extern bool    opt_prof_log;        /* Turn logging on at boot. */
extern char    opt_prof_prefix[
/* Minimize memory bloat for non-prof builds. */
#ifdef JEMALLOC_PROF
    PATH_MAX +
#endif
    1];
extern bool opt_prof_unbias;

/* Include pid namespace in profile file names. */
extern bool opt_prof_pid_namespace;

/* For recording recent allocations */
extern ssize_t opt_prof_recent_alloc_max;

/* Whether to use thread name provided by the system or by mallctl. */
extern bool opt_prof_sys_thread_name;

/* Whether to record per size class counts and request size totals. */
extern bool opt_prof_stats;

/* Accessed via prof_active_[gs]et{_unlocked,}(). */
extern bool prof_active_state;

/* Accessed via prof_gdump_[gs]et{_unlocked,}(). */
extern bool prof_gdump_val;

/* Profile dump interval, measured in bytes allocated. */
extern uint64_t prof_interval;

/*
 * Initialized as opt_lg_prof_sample, and potentially modified during profiling
 * resets.
 */
extern size_t lg_prof_sample;

extern bool prof_booted;

void                  prof_backtrace_hook_set(prof_backtrace_hook_t hook);
prof_backtrace_hook_t prof_backtrace_hook_get(void);

void             prof_dump_hook_set(prof_dump_hook_t hook);
prof_dump_hook_t prof_dump_hook_get(void);

void               prof_sample_hook_set(prof_sample_hook_t hook);
prof_sample_hook_t prof_sample_hook_get(void);

void                    prof_sample_free_hook_set(prof_sample_free_hook_t hook);
prof_sample_free_hook_t prof_sample_free_hook_get(void);

void                  prof_threshold_hook_set(prof_threshold_hook_t hook);
prof_threshold_hook_t prof_threshold_hook_get(void);

/* Functions only accessed in prof_inlines.h */
prof_tdata_t *prof_tdata_init(tsd_t *tsd);
prof_tdata_t *prof_tdata_reinit(tsd_t *tsd, prof_tdata_t *tdata);

void prof_alloc_rollback(tsd_t *tsd, prof_tctx_t *tctx);
void prof_malloc_sample_object(
    tsd_t *tsd, const void *ptr, size_t size, size_t usize, prof_tctx_t *tctx);
void prof_free_sampled_object(
    tsd_t *tsd, const void *ptr, size_t usize, prof_info_t *prof_info);
prof_tctx_t *prof_tctx_create(tsd_t *tsd);
void         prof_idump(tsdn_t *tsdn);
bool         prof_mdump(tsd_t *tsd, const char *filename);
void         prof_gdump(tsdn_t *tsdn);

void        prof_tdata_cleanup(tsd_t *tsd);
bool        prof_active_get(tsdn_t *tsdn);
bool        prof_active_set(tsdn_t *tsdn, bool active);
const char *prof_thread_name_get(tsd_t *tsd);
int         prof_thread_name_set(tsd_t *tsd, const char *thread_name);
bool        prof_thread_active_get(tsd_t *tsd);
bool        prof_thread_active_set(tsd_t *tsd, bool active);
bool        prof_thread_active_init_get(tsdn_t *tsdn);
bool        prof_thread_active_init_set(tsdn_t *tsdn, bool active_init);
bool        prof_gdump_get(tsdn_t *tsdn);
bool        prof_gdump_set(tsdn_t *tsdn, bool active);
void        prof_boot0(void);
void        prof_boot1(void);
bool        prof_boot2(tsd_t *tsd, base_t *base);
void        prof_prefork0(tsdn_t *tsdn);
void        prof_prefork1(tsdn_t *tsdn);
void        prof_postfork_parent(tsdn_t *tsdn);
void        prof_postfork_child(tsdn_t *tsdn);

uint64_t prof_sample_new_event_wait(tsd_t *tsd);
uint64_t tsd_prof_sample_event_wait_get(tsd_t *tsd);

/*
 * The lookahead functionality facilitates events to be able to lookahead, i.e.
 * without touching the event counters, to determine whether an event would be
 * triggered.  The event counters are not advanced until the end of the
 * allocation / deallocation calls, so the lookahead can be useful if some
 * preparation work for some event must be done early in the allocation /
 * deallocation calls.
 *
 * Currently only the profiling sampling event needs the lookahead
 * functionality, so we don't yet define general purpose lookahead functions.
 *
 * Surplus is a terminology referring to the amount of bytes beyond what's
 * needed for triggering an event, which can be a useful quantity to have in
 * general when lookahead is being called.
 *
 * This function returns true if allocation of usize would go above the next
 * trigger for prof event, and false otherwise.
 * If function returns true surplus will contain number of bytes beyond that
 * trigger.
 */

JEMALLOC_ALWAYS_INLINE bool
te_prof_sample_event_lookahead_surplus(
    tsd_t *tsd, size_t usize, size_t *surplus) {
	if (surplus != NULL) {
		/*
		 * This is a dead store: the surplus will be overwritten before
		 * any read.  The initialization suppresses compiler warnings.
		 * Meanwhile, using SIZE_MAX to initialize is good for
		 * debugging purpose, because a valid surplus value is strictly
		 * less than usize, which is at most SIZE_MAX.
		 */
		*surplus = SIZE_MAX;
	}
	if (unlikely(!tsd_nominal(tsd) || tsd_reentrancy_level_get(tsd) > 0)) {
		return false;
	}
	/* The subtraction is intentionally susceptible to underflow. */
	uint64_t accumbytes = tsd_thread_allocated_get(tsd) + usize
	    - tsd_thread_allocated_last_event_get(tsd);
	uint64_t sample_wait = tsd_prof_sample_event_wait_get(tsd);
	if (accumbytes < sample_wait) {
		return false;
	}
	assert(accumbytes - sample_wait < (uint64_t)usize);
	if (surplus != NULL) {
		*surplus = (size_t)(accumbytes - sample_wait);
	}
	return true;
}

JEMALLOC_ALWAYS_INLINE bool
te_prof_sample_event_lookahead(tsd_t *tsd, size_t usize) {
	return te_prof_sample_event_lookahead_surplus(tsd, usize, NULL);
}

extern te_base_cb_t prof_sample_te_handler;

#endif /* JEMALLOC_INTERNAL_PROF_EXTERNS_H */