[v4,15/19] net/ena: handle spurious wakeups in ENA wait event
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Commit Message
From: Stanislaw Kardach <kda@semihalf.com>
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 <kda@semihalf.com>
Reviewed-by: Michal Krawczyk <mk@semihalf.com>
Reviewed-by: Igor Chauskin <igorch@amazon.com>
Reviewed-by: Shay Agroskin <shayagr@amazon.com>
---
v4:
* Replace rte_panic with the error log.
drivers/net/ena/base/ena_plat_dpdk.h | 73 ++++++++++++++++++----------
1 file changed, 46 insertions(+), 27 deletions(-)
@@ -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 { \