From 072b9f2bbc2402a8c86194fe9e11458c1605540a Mon Sep 17 00:00:00 2001 From: Stanislaw Kardach Date: Tue, 11 May 2021 08:45:50 +0200 Subject: [PATCH] net/ena: handle spurious wakeups in wait event pthread_cond_timedwait() may spuriously wakeup according to POSIX. Therefore it is required to check whether predicate is actually true before finishing the waiting loop. Signed-off-by: Stanislaw Kardach Reviewed-by: Michal Krawczyk Reviewed-by: Igor Chauskin Reviewed-by: Shay Agroskin --- drivers/net/ena/base/ena_plat_dpdk.h | 73 ++++++++++++++++++---------- 1 file changed, 46 insertions(+), 27 deletions(-) diff --git a/drivers/net/ena/base/ena_plat_dpdk.h b/drivers/net/ena/base/ena_plat_dpdk.h index 13264d021b..f66df95591 100644 --- a/drivers/net/ena/base/ena_plat_dpdk.h +++ b/drivers/net/ena/base/ena_plat_dpdk.h @@ -77,6 +77,14 @@ typedef uint64_t dma_addr_t; #define mmiowb rte_io_wmb #define __iomem +#ifndef READ_ONCE +#define READ_ONCE(var) (*((volatile typeof(var) *)(&(var)))) +#endif + +#define READ_ONCE8(var) READ_ONCE(var) +#define READ_ONCE16(var) READ_ONCE(var) +#define READ_ONCE32(var) READ_ONCE(var) + #define US_PER_S 1000000 #define ENA_GET_SYSTEM_USECS() \ (rte_get_timer_cycles() * US_PER_S / rte_get_timer_hz()) @@ -138,40 +146,59 @@ extern int ena_logtype_com; ({(void)flags; rte_spinlock_unlock(&(spinlock)); }) #define ENA_SPINLOCK_DESTROY(spinlock) ((void)(spinlock)) -#define q_waitqueue_t \ - struct { \ - pthread_cond_t cond; \ - pthread_mutex_t mutex; \ - } +typedef struct { + pthread_cond_t cond; + pthread_mutex_t mutex; + uint8_t flag; +} ena_wait_event_t; -#define ena_wait_queue_t q_waitqueue_t - -#define ENA_WAIT_EVENT_INIT(waitqueue) \ +#define ENA_WAIT_EVENT_INIT(waitevent) \ do { \ - pthread_mutex_init(&(waitqueue).mutex, NULL); \ - pthread_cond_init(&(waitqueue).cond, NULL); \ + ena_wait_event_t *_we = &(waitevent); \ + pthread_mutex_init(&_we->mutex, NULL); \ + pthread_cond_init(&_we->cond, NULL); \ + _we->flag = 0; \ } while (0) #define ENA_WAIT_EVENT_WAIT(waitevent, timeout) \ do { \ + ena_wait_event_t *_we = &(waitevent); \ + typeof(timeout) _tmo = (timeout); \ + int ret = 0; \ struct timespec wait; \ struct timeval now; \ unsigned long timeout_us; \ gettimeofday(&now, NULL); \ - wait.tv_sec = now.tv_sec + (timeout) / 1000000UL; \ - timeout_us = (timeout) % 1000000UL; \ + wait.tv_sec = now.tv_sec + _tmo / 1000000UL; \ + timeout_us = _tmo % 1000000UL; \ wait.tv_nsec = (now.tv_usec + timeout_us) * 1000UL; \ - pthread_mutex_lock(&(waitevent).mutex); \ - pthread_cond_timedwait(&(waitevent).cond, \ - &(waitevent).mutex, &wait); \ - pthread_mutex_unlock(&(waitevent).mutex); \ + pthread_mutex_lock(&_we->mutex); \ + while (ret == 0 && !_we->flag) { \ + ret = pthread_cond_timedwait(&_we->cond, \ + &_we->mutex, &wait); \ + } \ + /* Asserts only if not working on ena_wait_event_t */ \ + if (unlikely(ret != 0 && ret != ETIMEDOUT)) \ + ena_trc_err(NULL, \ + "Invalid wait event. pthread ret: %d\n", ret); \ + else if (unlikely(ret == ETIMEDOUT)) \ + ena_trc_err(NULL, \ + "Timeout waiting for " #waitevent "\n"); \ + _we->flag = 0; \ + pthread_mutex_unlock(&_we->mutex); \ + } while (0) +#define ENA_WAIT_EVENT_SIGNAL(waitevent) \ + do { \ + ena_wait_event_t *_we = &(waitevent); \ + pthread_mutex_lock(&_we->mutex); \ + _we->flag = 1; \ + pthread_cond_signal(&_we->cond); \ + pthread_mutex_unlock(&_we->mutex); \ } while (0) -#define ENA_WAIT_EVENT_SIGNAL(waitevent) pthread_cond_signal(&waitevent.cond) /* pthread condition doesn't need to be rearmed after usage */ #define ENA_WAIT_EVENT_CLEAR(...) -#define ENA_WAIT_EVENT_DESTROY(waitqueue) ((void)(waitqueue)) +#define ENA_WAIT_EVENT_DESTROY(waitevent) ((void)(waitevent)) -#define ena_wait_event_t ena_wait_queue_t #define ENA_MIGHT_SLEEP() #define ena_time_t uint64_t @@ -289,14 +316,6 @@ extern rte_atomic64_t ena_alloc_cnt; ((timeout_us) * rte_get_timer_hz() / 1000000 + rte_get_timer_cycles()) #define ENA_WAIT_EVENTS_DESTROY(admin_queue) ((void)(admin_queue)) -#ifndef READ_ONCE -#define READ_ONCE(var) (*((volatile typeof(var) *)(&(var)))) -#endif - -#define READ_ONCE8(var) READ_ONCE(var) -#define READ_ONCE16(var) READ_ONCE(var) -#define READ_ONCE32(var) READ_ONCE(var) - /* The size must be 8 byte align */ #define ENA_MEMCPY_TO_DEVICE_64(dst, src, size) \ do { \ -- 2.20.1