diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c index 0918d3f003d6..13556fdda2a5 100644 --- a/drivers/dma-buf/dma-fence.c +++ b/drivers/dma-buf/dma-fence.c @@ -75,11 +75,6 @@ int dma_fence_signal_locked(struct dma_fence *fence) if (WARN_ON(!fence)) return -EINVAL; - if (!ktime_to_ns(fence->timestamp)) { - fence->timestamp = ktime_get(); - smp_mb__before_atomic(); - } - if (test_and_set_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) { ret = -EINVAL; @@ -87,8 +82,11 @@ int dma_fence_signal_locked(struct dma_fence *fence) * we might have raced with the unlocked dma_fence_signal, * still run through all callbacks */ - } else + } else { + fence->timestamp = ktime_get(); + set_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags); trace_dma_fence_signaled(fence); + } list_for_each_entry_safe(cur, tmp, &fence->cb_list, node) { list_del_init(&cur->node); @@ -115,14 +113,11 @@ int dma_fence_signal(struct dma_fence *fence) if (!fence) return -EINVAL; - if (!ktime_to_ns(fence->timestamp)) { - fence->timestamp = ktime_get(); - smp_mb__before_atomic(); - } - if (test_and_set_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) return -EINVAL; + fence->timestamp = ktime_get(); + set_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags); trace_dma_fence_signaled(fence); if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags)) { diff --git a/drivers/dma-buf/sync_debug.c b/drivers/dma-buf/sync_debug.c index c769dc653b34..bfead12390f2 100644 --- a/drivers/dma-buf/sync_debug.c +++ b/drivers/dma-buf/sync_debug.c @@ -84,7 +84,7 @@ static void sync_print_fence(struct seq_file *s, show ? "_" : "", sync_status_str(status)); - if (status) { + if (test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags)) { struct timespec64 ts64 = ktime_to_timespec64(fence->timestamp); diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c index 2321035f6204..95f259b719fc 100644 --- a/drivers/dma-buf/sync_file.c +++ b/drivers/dma-buf/sync_file.c @@ -375,7 +375,13 @@ static void sync_fill_fence_info(struct dma_fence *fence, sizeof(info->driver_name)); info->status = dma_fence_get_status(fence); - info->timestamp_ns = ktime_to_ns(fence->timestamp); + while (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags) && + !test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags)) + cpu_relax(); + info->timestamp_ns = + test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags) ? + ktime_to_ns(fence->timestamp) : + ktime_set(0, 0); } static long sync_file_ioctl_fence_info(struct sync_file *sync_file, diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h index a5195a7d6f77..0a186c4f3981 100644 --- a/include/linux/dma-fence.h +++ b/include/linux/dma-fence.h @@ -55,6 +55,7 @@ struct dma_fence_cb; * of the time. * * DMA_FENCE_FLAG_SIGNALED_BIT - fence is already signaled + * DMA_FENCE_FLAG_TIMESTAMP_BIT - timestamp recorded for fence signaling * DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT - enable_signaling might have been called * DMA_FENCE_FLAG_USER_BITS - start of the unused bits, can be used by the * implementer of the fence for its own purposes. Can be used in different @@ -84,6 +85,7 @@ struct dma_fence { enum dma_fence_flag_bits { DMA_FENCE_FLAG_SIGNALED_BIT, + DMA_FENCE_FLAG_TIMESTAMP_BIT, DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, DMA_FENCE_FLAG_USER_BITS, /* must always be last member */ };