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server-skynet-source-3rd-je.../include/jemalloc/internal/mutex.h

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Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
#ifndef JEMALLOC_INTERNAL_MUTEX_H
#define JEMALLOC_INTERNAL_MUTEX_H
#include "jemalloc/internal/atomic.h"
#include "jemalloc/internal/mutex_prof.h"
#include "jemalloc/internal/tsd.h"
#include "jemalloc/internal/witness.h"
typedef enum {
/* Can only acquire one mutex of a given witness rank at a time. */
malloc_mutex_rank_exclusive,
/*
* Can acquire multiple mutexes of the same witness rank, but in
* address-ascending order only.
*/
malloc_mutex_address_ordered
} malloc_mutex_lock_order_t;
typedef struct malloc_mutex_s malloc_mutex_t;
struct malloc_mutex_s {
union {
struct {
/*
* prof_data is defined first to reduce cacheline
* bouncing: the data is not touched by the mutex holder
* during unlocking, while might be modified by
* contenders. Having it before the mutex itself could
* avoid prefetching a modified cacheline (for the
* unlocking thread).
*/
mutex_prof_data_t prof_data;
#ifdef _WIN32
# if _WIN32_WINNT >= 0x0600
SRWLOCK lock;
# else
CRITICAL_SECTION lock;
# endif
#elif (defined(JEMALLOC_OS_UNFAIR_LOCK))
os_unfair_lock lock;
#elif (defined(JEMALLOC_MUTEX_INIT_CB))
pthread_mutex_t lock;
malloc_mutex_t *postponed_next;
#else
pthread_mutex_t lock;
#endif
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
/*
* Hint flag to avoid exclusive cache line contention
* during spin waiting
*/
atomic_b_t locked;
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
};
/*
* We only touch witness when configured w/ debug. However we
* keep the field in a union when !debug so that we don't have
* to pollute the code base with #ifdefs, while avoid paying the
* memory cost.
*/
#if !defined(JEMALLOC_DEBUG)
witness_t witness;
malloc_mutex_lock_order_t lock_order;
#endif
};
#if defined(JEMALLOC_DEBUG)
witness_t witness;
malloc_mutex_lock_order_t lock_order;
#endif
};
/*
* Based on benchmark results, a fixed spin with this amount of retries works
* well for our critical sections.
*/
#define MALLOC_MUTEX_MAX_SPIN 250
#ifdef _WIN32
# if _WIN32_WINNT >= 0x0600
# define MALLOC_MUTEX_LOCK(m) AcquireSRWLockExclusive(&(m)->lock)
# define MALLOC_MUTEX_UNLOCK(m) ReleaseSRWLockExclusive(&(m)->lock)
# define MALLOC_MUTEX_TRYLOCK(m) (!TryAcquireSRWLockExclusive(&(m)->lock))
# else
# define MALLOC_MUTEX_LOCK(m) EnterCriticalSection(&(m)->lock)
# define MALLOC_MUTEX_UNLOCK(m) LeaveCriticalSection(&(m)->lock)
# define MALLOC_MUTEX_TRYLOCK(m) (!TryEnterCriticalSection(&(m)->lock))
# endif
#elif (defined(JEMALLOC_OS_UNFAIR_LOCK))
# define MALLOC_MUTEX_LOCK(m) os_unfair_lock_lock(&(m)->lock)
# define MALLOC_MUTEX_UNLOCK(m) os_unfair_lock_unlock(&(m)->lock)
# define MALLOC_MUTEX_TRYLOCK(m) (!os_unfair_lock_trylock(&(m)->lock))
#else
# define MALLOC_MUTEX_LOCK(m) pthread_mutex_lock(&(m)->lock)
# define MALLOC_MUTEX_UNLOCK(m) pthread_mutex_unlock(&(m)->lock)
# define MALLOC_MUTEX_TRYLOCK(m) (pthread_mutex_trylock(&(m)->lock) != 0)
#endif
#define LOCK_PROF_DATA_INITIALIZER \
{NSTIME_ZERO_INITIALIZER, NSTIME_ZERO_INITIALIZER, 0, 0, 0, \
ATOMIC_INIT(0), 0, NULL, 0}
#ifdef _WIN32
# define MALLOC_MUTEX_INITIALIZER
#elif (defined(JEMALLOC_OS_UNFAIR_LOCK))
Clean compilation -Wextra Before this commit jemalloc produced many warnings when compiled with -Wextra with both Clang and GCC. This commit fixes the issues raised by these warnings or suppresses them if they were spurious at least for the Clang and GCC versions covered by CI. This commit: * adds `JEMALLOC_DIAGNOSTIC` macros: `JEMALLOC_DIAGNOSTIC_{PUSH,POP}` are used to modify the stack of enabled diagnostics. The `JEMALLOC_DIAGNOSTIC_IGNORE_...` macros are used to ignore a concrete diagnostic. * adds `JEMALLOC_FALLTHROUGH` macro to explicitly state that falling through `case` labels in a `switch` statement is intended * Removes all UNUSED annotations on function parameters. The warning -Wunused-parameter is now disabled globally in `jemalloc_internal_macros.h` for all translation units that include that header. It is never re-enabled since that header cannot be included by users. * locally suppresses some -Wextra diagnostics: * `-Wmissing-field-initializer` is buggy in older Clang and GCC versions, where it does not understanding that, in C, `= {0}` is a common C idiom to initialize a struct to zero * `-Wtype-bounds` is suppressed in a particular situation where a generic macro, used in multiple different places, compares an unsigned integer for smaller than zero, which is always true. * `-Walloc-larger-than-size=` diagnostics warn when an allocation function is called with a size that is too large (out-of-range). These are suppressed in the parts of the tests where `jemalloc` explicitly does this to test that the allocation functions fail properly. * adds a new CI build bot that runs the log unit test on CI. Closes #1196 .
2018-05-03 17:40:53 +08:00
# if defined(JEMALLOC_DEBUG)
# define MALLOC_MUTEX_INITIALIZER \
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
{{{LOCK_PROF_DATA_INITIALIZER, OS_UNFAIR_LOCK_INIT, ATOMIC_INIT(false)}}, \
Clean compilation -Wextra Before this commit jemalloc produced many warnings when compiled with -Wextra with both Clang and GCC. This commit fixes the issues raised by these warnings or suppresses them if they were spurious at least for the Clang and GCC versions covered by CI. This commit: * adds `JEMALLOC_DIAGNOSTIC` macros: `JEMALLOC_DIAGNOSTIC_{PUSH,POP}` are used to modify the stack of enabled diagnostics. The `JEMALLOC_DIAGNOSTIC_IGNORE_...` macros are used to ignore a concrete diagnostic. * adds `JEMALLOC_FALLTHROUGH` macro to explicitly state that falling through `case` labels in a `switch` statement is intended * Removes all UNUSED annotations on function parameters. The warning -Wunused-parameter is now disabled globally in `jemalloc_internal_macros.h` for all translation units that include that header. It is never re-enabled since that header cannot be included by users. * locally suppresses some -Wextra diagnostics: * `-Wmissing-field-initializer` is buggy in older Clang and GCC versions, where it does not understanding that, in C, `= {0}` is a common C idiom to initialize a struct to zero * `-Wtype-bounds` is suppressed in a particular situation where a generic macro, used in multiple different places, compares an unsigned integer for smaller than zero, which is always true. * `-Walloc-larger-than-size=` diagnostics warn when an allocation function is called with a size that is too large (out-of-range). These are suppressed in the parts of the tests where `jemalloc` explicitly does this to test that the allocation functions fail properly. * adds a new CI build bot that runs the log unit test on CI. Closes #1196 .
2018-05-03 17:40:53 +08:00
WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT), 0}
# else
# define MALLOC_MUTEX_INITIALIZER \
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
{{{LOCK_PROF_DATA_INITIALIZER, OS_UNFAIR_LOCK_INIT, ATOMIC_INIT(false)}}, \
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT)}
Clean compilation -Wextra Before this commit jemalloc produced many warnings when compiled with -Wextra with both Clang and GCC. This commit fixes the issues raised by these warnings or suppresses them if they were spurious at least for the Clang and GCC versions covered by CI. This commit: * adds `JEMALLOC_DIAGNOSTIC` macros: `JEMALLOC_DIAGNOSTIC_{PUSH,POP}` are used to modify the stack of enabled diagnostics. The `JEMALLOC_DIAGNOSTIC_IGNORE_...` macros are used to ignore a concrete diagnostic. * adds `JEMALLOC_FALLTHROUGH` macro to explicitly state that falling through `case` labels in a `switch` statement is intended * Removes all UNUSED annotations on function parameters. The warning -Wunused-parameter is now disabled globally in `jemalloc_internal_macros.h` for all translation units that include that header. It is never re-enabled since that header cannot be included by users. * locally suppresses some -Wextra diagnostics: * `-Wmissing-field-initializer` is buggy in older Clang and GCC versions, where it does not understanding that, in C, `= {0}` is a common C idiom to initialize a struct to zero * `-Wtype-bounds` is suppressed in a particular situation where a generic macro, used in multiple different places, compares an unsigned integer for smaller than zero, which is always true. * `-Walloc-larger-than-size=` diagnostics warn when an allocation function is called with a size that is too large (out-of-range). These are suppressed in the parts of the tests where `jemalloc` explicitly does this to test that the allocation functions fail properly. * adds a new CI build bot that runs the log unit test on CI. Closes #1196 .
2018-05-03 17:40:53 +08:00
# endif
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
#elif (defined(JEMALLOC_MUTEX_INIT_CB))
FreeBSD build changes and allow to run the tests.
2018-08-05 17:37:53 +08:00
# if (defined(JEMALLOC_DEBUG))
# define MALLOC_MUTEX_INITIALIZER \
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
{{{LOCK_PROF_DATA_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, NULL, ATOMIC_INIT(false)}}, \
FreeBSD build changes and allow to run the tests.
2018-08-05 17:37:53 +08:00
WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT), 0}
# else
# define MALLOC_MUTEX_INITIALIZER \
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
{{{LOCK_PROF_DATA_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, NULL, ATOMIC_INIT(false)}}, \
FreeBSD build changes and allow to run the tests.
2018-08-05 17:37:53 +08:00
WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT)}
# endif
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
#else
# define MALLOC_MUTEX_TYPE PTHREAD_MUTEX_DEFAULT
Clean compilation -Wextra Before this commit jemalloc produced many warnings when compiled with -Wextra with both Clang and GCC. This commit fixes the issues raised by these warnings or suppresses them if they were spurious at least for the Clang and GCC versions covered by CI. This commit: * adds `JEMALLOC_DIAGNOSTIC` macros: `JEMALLOC_DIAGNOSTIC_{PUSH,POP}` are used to modify the stack of enabled diagnostics. The `JEMALLOC_DIAGNOSTIC_IGNORE_...` macros are used to ignore a concrete diagnostic. * adds `JEMALLOC_FALLTHROUGH` macro to explicitly state that falling through `case` labels in a `switch` statement is intended * Removes all UNUSED annotations on function parameters. The warning -Wunused-parameter is now disabled globally in `jemalloc_internal_macros.h` for all translation units that include that header. It is never re-enabled since that header cannot be included by users. * locally suppresses some -Wextra diagnostics: * `-Wmissing-field-initializer` is buggy in older Clang and GCC versions, where it does not understanding that, in C, `= {0}` is a common C idiom to initialize a struct to zero * `-Wtype-bounds` is suppressed in a particular situation where a generic macro, used in multiple different places, compares an unsigned integer for smaller than zero, which is always true. * `-Walloc-larger-than-size=` diagnostics warn when an allocation function is called with a size that is too large (out-of-range). These are suppressed in the parts of the tests where `jemalloc` explicitly does this to test that the allocation functions fail properly. * adds a new CI build bot that runs the log unit test on CI. Closes #1196 .
2018-05-03 17:40:53 +08:00
# if defined(JEMALLOC_DEBUG)
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
# define MALLOC_MUTEX_INITIALIZER \
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
{{{LOCK_PROF_DATA_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, ATOMIC_INIT(false)}}, \
Clean compilation -Wextra Before this commit jemalloc produced many warnings when compiled with -Wextra with both Clang and GCC. This commit fixes the issues raised by these warnings or suppresses them if they were spurious at least for the Clang and GCC versions covered by CI. This commit: * adds `JEMALLOC_DIAGNOSTIC` macros: `JEMALLOC_DIAGNOSTIC_{PUSH,POP}` are used to modify the stack of enabled diagnostics. The `JEMALLOC_DIAGNOSTIC_IGNORE_...` macros are used to ignore a concrete diagnostic. * adds `JEMALLOC_FALLTHROUGH` macro to explicitly state that falling through `case` labels in a `switch` statement is intended * Removes all UNUSED annotations on function parameters. The warning -Wunused-parameter is now disabled globally in `jemalloc_internal_macros.h` for all translation units that include that header. It is never re-enabled since that header cannot be included by users. * locally suppresses some -Wextra diagnostics: * `-Wmissing-field-initializer` is buggy in older Clang and GCC versions, where it does not understanding that, in C, `= {0}` is a common C idiom to initialize a struct to zero * `-Wtype-bounds` is suppressed in a particular situation where a generic macro, used in multiple different places, compares an unsigned integer for smaller than zero, which is always true. * `-Walloc-larger-than-size=` diagnostics warn when an allocation function is called with a size that is too large (out-of-range). These are suppressed in the parts of the tests where `jemalloc` explicitly does this to test that the allocation functions fail properly. * adds a new CI build bot that runs the log unit test on CI. Closes #1196 .
2018-05-03 17:40:53 +08:00
WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT), 0}
# else
# define MALLOC_MUTEX_INITIALIZER \
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
{{{LOCK_PROF_DATA_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, ATOMIC_INIT(false)}}, \
Clean compilation -Wextra Before this commit jemalloc produced many warnings when compiled with -Wextra with both Clang and GCC. This commit fixes the issues raised by these warnings or suppresses them if they were spurious at least for the Clang and GCC versions covered by CI. This commit: * adds `JEMALLOC_DIAGNOSTIC` macros: `JEMALLOC_DIAGNOSTIC_{PUSH,POP}` are used to modify the stack of enabled diagnostics. The `JEMALLOC_DIAGNOSTIC_IGNORE_...` macros are used to ignore a concrete diagnostic. * adds `JEMALLOC_FALLTHROUGH` macro to explicitly state that falling through `case` labels in a `switch` statement is intended * Removes all UNUSED annotations on function parameters. The warning -Wunused-parameter is now disabled globally in `jemalloc_internal_macros.h` for all translation units that include that header. It is never re-enabled since that header cannot be included by users. * locally suppresses some -Wextra diagnostics: * `-Wmissing-field-initializer` is buggy in older Clang and GCC versions, where it does not understanding that, in C, `= {0}` is a common C idiom to initialize a struct to zero * `-Wtype-bounds` is suppressed in a particular situation where a generic macro, used in multiple different places, compares an unsigned integer for smaller than zero, which is always true. * `-Walloc-larger-than-size=` diagnostics warn when an allocation function is called with a size that is too large (out-of-range). These are suppressed in the parts of the tests where `jemalloc` explicitly does this to test that the allocation functions fail properly. * adds a new CI build bot that runs the log unit test on CI. Closes #1196 .
2018-05-03 17:40:53 +08:00
WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT)}
# endif
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
#endif
#ifdef JEMALLOC_LAZY_LOCK
extern bool isthreaded;
#else
# undef isthreaded /* Undo private_namespace.h definition. */
# define isthreaded true
#endif
bool malloc_mutex_init(malloc_mutex_t *mutex, const char *name,
witness_rank_t rank, malloc_mutex_lock_order_t lock_order);
void malloc_mutex_prefork(tsdn_t *tsdn, malloc_mutex_t *mutex);
void malloc_mutex_postfork_parent(tsdn_t *tsdn, malloc_mutex_t *mutex);
void malloc_mutex_postfork_child(tsdn_t *tsdn, malloc_mutex_t *mutex);
bool malloc_mutex_boot(void);
void malloc_mutex_prof_data_reset(tsdn_t *tsdn, malloc_mutex_t *mutex);
void malloc_mutex_lock_slow(malloc_mutex_t *mutex);
static inline void
malloc_mutex_lock_final(malloc_mutex_t *mutex) {
MALLOC_MUTEX_LOCK(mutex);
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
atomic_store_b(&mutex->locked, true, ATOMIC_RELAXED);
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
}
static inline bool
malloc_mutex_trylock_final(malloc_mutex_t *mutex) {
return MALLOC_MUTEX_TRYLOCK(mutex);
}
static inline void
mutex_owner_stats_update(tsdn_t *tsdn, malloc_mutex_t *mutex) {
if (config_stats) {
mutex_prof_data_t *data = &mutex->prof_data;
data->n_lock_ops++;
if (data->prev_owner != tsdn) {
data->prev_owner = tsdn;
data->n_owner_switches++;
}
}
}
/* Trylock: return false if the lock is successfully acquired. */
static inline bool
malloc_mutex_trylock(tsdn_t *tsdn, malloc_mutex_t *mutex) {
witness_assert_not_owner(tsdn_witness_tsdp_get(tsdn), &mutex->witness);
if (isthreaded) {
if (malloc_mutex_trylock_final(mutex)) {
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
atomic_store_b(&mutex->locked, true, ATOMIC_RELAXED);
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
return true;
}
mutex_owner_stats_update(tsdn, mutex);
}
witness_lock(tsdn_witness_tsdp_get(tsdn), &mutex->witness);
return false;
}
/* Aggregate lock prof data. */
static inline void
malloc_mutex_prof_merge(mutex_prof_data_t *sum, mutex_prof_data_t *data) {
nstime_add(&sum->tot_wait_time, &data->tot_wait_time);
if (nstime_compare(&sum->max_wait_time, &data->max_wait_time) < 0) {
nstime_copy(&sum->max_wait_time, &data->max_wait_time);
}
sum->n_wait_times += data->n_wait_times;
sum->n_spin_acquired += data->n_spin_acquired;
if (sum->max_n_thds < data->max_n_thds) {
sum->max_n_thds = data->max_n_thds;
}
uint32_t cur_n_waiting_thds = atomic_load_u32(&sum->n_waiting_thds,
ATOMIC_RELAXED);
uint32_t new_n_waiting_thds = cur_n_waiting_thds + atomic_load_u32(
&data->n_waiting_thds, ATOMIC_RELAXED);
atomic_store_u32(&sum->n_waiting_thds, new_n_waiting_thds,
ATOMIC_RELAXED);
sum->n_owner_switches += data->n_owner_switches;
sum->n_lock_ops += data->n_lock_ops;
}
static inline void
malloc_mutex_lock(tsdn_t *tsdn, malloc_mutex_t *mutex) {
witness_assert_not_owner(tsdn_witness_tsdp_get(tsdn), &mutex->witness);
if (isthreaded) {
if (malloc_mutex_trylock_final(mutex)) {
malloc_mutex_lock_slow(mutex);
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
atomic_store_b(&mutex->locked, true, ATOMIC_RELAXED);
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
}
mutex_owner_stats_update(tsdn, mutex);
}
witness_lock(tsdn_witness_tsdp_get(tsdn), &mutex->witness);
}
static inline void
malloc_mutex_unlock(tsdn_t *tsdn, malloc_mutex_t *mutex) {
mutex: fix trylock spin wait contention If there are 3 or more threads spin-waiting on the same mutex, there will be excessive exclusive cacheline contention because pthread_trylock() immediately tries to CAS in a new value, instead of first checking if the lock is locked. This diff adds a 'locked' hint flag, and we will only spin wait without trylock()ing while set. I don't know of any other portable way to get the same behavior as pthread_mutex_lock(). This is pretty easy to test via ttest, e.g. ./ttest1 500 3 10000 1 100 Throughput is nearly 3x as fast. This blames to the mutex profiling changes, however, we almost never have 3 or more threads contending in properly configured production workloads, but still worth fixing.
2018-11-27 00:11:00 +08:00
atomic_store_b(&mutex->locked, false, ATOMIC_RELAXED);
Header refactoring: unify and de-catchall mutex module
2017-05-24 03:28:19 +08:00
witness_unlock(tsdn_witness_tsdp_get(tsdn), &mutex->witness);
if (isthreaded) {
MALLOC_MUTEX_UNLOCK(mutex);
}
}
static inline void
malloc_mutex_assert_owner(tsdn_t *tsdn, malloc_mutex_t *mutex) {
witness_assert_owner(tsdn_witness_tsdp_get(tsdn), &mutex->witness);
}
static inline void
malloc_mutex_assert_not_owner(tsdn_t *tsdn, malloc_mutex_t *mutex) {
witness_assert_not_owner(tsdn_witness_tsdp_get(tsdn), &mutex->witness);
}
/* Copy the prof data from mutex for processing. */
static inline void
malloc_mutex_prof_read(tsdn_t *tsdn, mutex_prof_data_t *data,
malloc_mutex_t *mutex) {
mutex_prof_data_t *source = &mutex->prof_data;
/* Can only read holding the mutex. */
malloc_mutex_assert_owner(tsdn, mutex);
/*
* Not *really* allowed (we shouldn't be doing non-atomic loads of
* atomic data), but the mutex protection makes this safe, and writing
* a member-for-member copy is tedious for this situation.
*/
*data = *source;
/* n_wait_thds is not reported (modified w/o locking). */
atomic_store_u32(&data->n_waiting_thds, 0, ATOMIC_RELAXED);
}
#endif /* JEMALLOC_INTERNAL_MUTEX_H */
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