From 3dcc9c6ec4ea60fd1464b35aa82199483f24ba75 Mon Sep 17 00:00:00 2001 From: Yury Kotov Date: Mon, 9 Sep 2019 16:13:33 +0300 Subject: [PATCH] qemu-thread: Add qemu_cond_timedwait The new function is needed to implement conditional sleep for CPU throttling. It's possible to reuse qemu_sem_timedwait, but it's more difficult than just add qemu_cond_timedwait. Also moved compute_abs_deadline function up the code to reuse it in qemu_cond_timedwait_impl win32. Signed-off-by: Yury Kotov Message-Id: <20190909131335.16848-2-yury-kotov@yandex-team.ru> Signed-off-by: Paolo Bonzini --- include/qemu/thread.h | 19 +++++++++++++++++++ util/qemu-thread-posix.c | 41 +++++++++++++++++++++++++++++------------ util/qemu-thread-win32.c | 17 +++++++++++++++++ util/qsp.c | 20 ++++++++++++++++++++ 4 files changed, 85 insertions(+), 12 deletions(-) diff --git a/include/qemu/thread.h b/include/qemu/thread.h index 55d83a907c..047db0307e 100644 --- a/include/qemu/thread.h +++ b/include/qemu/thread.h @@ -34,6 +34,8 @@ typedef void (*QemuRecMutexLockFunc)(QemuRecMutex *m, const char *f, int l); typedef int (*QemuRecMutexTrylockFunc)(QemuRecMutex *m, const char *f, int l); typedef void (*QemuCondWaitFunc)(QemuCond *c, QemuMutex *m, const char *f, int l); +typedef bool (*QemuCondTimedWaitFunc)(QemuCond *c, QemuMutex *m, int ms, + const char *f, int l); extern QemuMutexLockFunc qemu_bql_mutex_lock_func; extern QemuMutexLockFunc qemu_mutex_lock_func; @@ -41,6 +43,7 @@ extern QemuMutexTrylockFunc qemu_mutex_trylock_func; extern QemuRecMutexLockFunc qemu_rec_mutex_lock_func; extern QemuRecMutexTrylockFunc qemu_rec_mutex_trylock_func; extern QemuCondWaitFunc qemu_cond_wait_func; +extern QemuCondTimedWaitFunc qemu_cond_timedwait_func; /* convenience macros to bypass the profiler */ #define qemu_mutex_lock__raw(m) \ @@ -63,6 +66,8 @@ extern QemuCondWaitFunc qemu_cond_wait_func; qemu_rec_mutex_trylock_impl(m, __FILE__, __LINE__); #define qemu_cond_wait(c, m) \ qemu_cond_wait_impl(c, m, __FILE__, __LINE__); +#define qemu_cond_timedwait(c, m, ms) \ + qemu_cond_wait_impl(c, m, ms, __FILE__, __LINE__); #else #define qemu_mutex_lock(m) ({ \ QemuMutexLockFunc _f = atomic_read(&qemu_mutex_lock_func); \ @@ -89,6 +94,11 @@ extern QemuCondWaitFunc qemu_cond_wait_func; QemuCondWaitFunc _f = atomic_read(&qemu_cond_wait_func); \ _f(c, m, __FILE__, __LINE__); \ }) + +#define qemu_cond_timedwait(c, m, ms) ({ \ + QemuCondTimedWaitFunc _f = atomic_read(&qemu_cond_timedwait_func); \ + _f(c, m, ms, __FILE__, __LINE__); \ + }) #endif #define qemu_mutex_unlock(mutex) \ @@ -134,12 +144,21 @@ void qemu_cond_signal(QemuCond *cond); void qemu_cond_broadcast(QemuCond *cond); void qemu_cond_wait_impl(QemuCond *cond, QemuMutex *mutex, const char *file, const int line); +bool qemu_cond_timedwait_impl(QemuCond *cond, QemuMutex *mutex, int ms, + const char *file, const int line); static inline void (qemu_cond_wait)(QemuCond *cond, QemuMutex *mutex) { qemu_cond_wait(cond, mutex); } +/* Returns true if timeout has not expired, and false otherwise */ +static inline bool (qemu_cond_timedwait)(QemuCond *cond, QemuMutex *mutex, + int ms) +{ + return qemu_cond_timedwait(cond, mutex, ms); +} + void qemu_sem_init(QemuSemaphore *sem, int init); void qemu_sem_post(QemuSemaphore *sem); void qemu_sem_wait(QemuSemaphore *sem); diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c index 1bf5e65dea..838980aaa5 100644 --- a/util/qemu-thread-posix.c +++ b/util/qemu-thread-posix.c @@ -36,6 +36,18 @@ static void error_exit(int err, const char *msg) abort(); } +static void compute_abs_deadline(struct timespec *ts, int ms) +{ + struct timeval tv; + gettimeofday(&tv, NULL); + ts->tv_nsec = tv.tv_usec * 1000 + (ms % 1000) * 1000000; + ts->tv_sec = tv.tv_sec + ms / 1000; + if (ts->tv_nsec >= 1000000000) { + ts->tv_sec++; + ts->tv_nsec -= 1000000000; + } +} + void qemu_mutex_init(QemuMutex *mutex) { int err; @@ -164,6 +176,23 @@ void qemu_cond_wait_impl(QemuCond *cond, QemuMutex *mutex, const char *file, con error_exit(err, __func__); } +bool qemu_cond_timedwait_impl(QemuCond *cond, QemuMutex *mutex, int ms, + const char *file, const int line) +{ + int err; + struct timespec ts; + + assert(cond->initialized); + trace_qemu_mutex_unlock(mutex, file, line); + compute_abs_deadline(&ts, ms); + err = pthread_cond_timedwait(&cond->cond, &mutex->lock, &ts); + trace_qemu_mutex_locked(mutex, file, line); + if (err && err != ETIMEDOUT) { + error_exit(err, __func__); + } + return err != ETIMEDOUT; +} + void qemu_sem_init(QemuSemaphore *sem, int init) { int rc; @@ -238,18 +267,6 @@ void qemu_sem_post(QemuSemaphore *sem) #endif } -static void compute_abs_deadline(struct timespec *ts, int ms) -{ - struct timeval tv; - gettimeofday(&tv, NULL); - ts->tv_nsec = tv.tv_usec * 1000 + (ms % 1000) * 1000000; - ts->tv_sec = tv.tv_sec + ms / 1000; - if (ts->tv_nsec >= 1000000000) { - ts->tv_sec++; - ts->tv_nsec -= 1000000000; - } -} - int qemu_sem_timedwait(QemuSemaphore *sem, int ms) { int rc; diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c index 572f88535d..56a83333da 100644 --- a/util/qemu-thread-win32.c +++ b/util/qemu-thread-win32.c @@ -145,6 +145,23 @@ void qemu_cond_wait_impl(QemuCond *cond, QemuMutex *mutex, const char *file, con qemu_mutex_post_lock(mutex, file, line); } +bool qemu_cond_timedwait_impl(QemuCond *cond, QemuMutex *mutex, int ms, + const char *file, const int line) +{ + int rc = 0; + + assert(cond->initialized); + trace_qemu_mutex_unlock(mutex, file, line); + if (!SleepConditionVariableSRW(&cond->var, &mutex->lock, ms, 0)) { + rc = GetLastError(); + } + trace_qemu_mutex_locked(mutex, file, line); + if (rc && rc != ERROR_TIMEOUT) { + error_exit(rc, __func__); + } + return rc != ERROR_TIMEOUT; +} + void qemu_sem_init(QemuSemaphore *sem, int init) { /* Manual reset. */ diff --git a/util/qsp.c b/util/qsp.c index 5264c97342..62265417fd 100644 --- a/util/qsp.c +++ b/util/qsp.c @@ -131,6 +131,7 @@ QemuRecMutexLockFunc qemu_rec_mutex_lock_func = qemu_rec_mutex_lock_impl; QemuRecMutexTrylockFunc qemu_rec_mutex_trylock_func = qemu_rec_mutex_trylock_impl; QemuCondWaitFunc qemu_cond_wait_func = qemu_cond_wait_impl; +QemuCondTimedWaitFunc qemu_cond_timedwait_func = qemu_cond_timedwait_impl; /* * It pays off to _not_ hash callsite->file; hashing a string is slow, and @@ -412,6 +413,23 @@ qsp_cond_wait(QemuCond *cond, QemuMutex *mutex, const char *file, int line) qsp_entry_record(e, t1 - t0); } +static bool +qsp_cond_timedwait(QemuCond *cond, QemuMutex *mutex, int ms, + const char *file, int line) +{ + QSPEntry *e; + int64_t t0, t1; + bool ret; + + t0 = get_clock(); + ret = qemu_cond_timedwait_impl(cond, mutex, ms, file, line); + t1 = get_clock(); + + e = qsp_entry_get(cond, file, line, QSP_CONDVAR); + qsp_entry_record(e, t1 - t0); + return ret; +} + bool qsp_is_enabled(void) { return atomic_read(&qemu_mutex_lock_func) == qsp_mutex_lock; @@ -425,6 +443,7 @@ void qsp_enable(void) atomic_set(&qemu_rec_mutex_lock_func, qsp_rec_mutex_lock); atomic_set(&qemu_rec_mutex_trylock_func, qsp_rec_mutex_trylock); atomic_set(&qemu_cond_wait_func, qsp_cond_wait); + atomic_set(&qemu_cond_timedwait_func, qsp_cond_timedwait); } void qsp_disable(void) @@ -435,6 +454,7 @@ void qsp_disable(void) atomic_set(&qemu_rec_mutex_lock_func, qemu_rec_mutex_lock_impl); atomic_set(&qemu_rec_mutex_trylock_func, qemu_rec_mutex_trylock_impl); atomic_set(&qemu_cond_wait_func, qemu_cond_wait_impl); + atomic_set(&qemu_cond_timedwait_func, qemu_cond_timedwait_impl); } static gint qsp_tree_cmp(gconstpointer ap, gconstpointer bp, gpointer up) -- 2.11.4.GIT