diff options
author | Ofir Bitton <obitton@habana.ai> | 2021-03-18 16:36:57 +0100 |
---|---|---|
committer | Oded Gabbay <ogabbay@kernel.org> | 2021-04-09 13:09:24 +0200 |
commit | 8445dde1b9fb8025ef05c148966f384a4d014824 (patch) | |
tree | b913954b737bdb945665c20e40d14a4a41233436 /drivers/misc/habanalabs | |
parent | habanalabs: avoid soft lockup bug upon mapping error (diff) | |
download | linux-8445dde1b9fb8025ef05c148966f384a4d014824.tar.xz linux-8445dde1b9fb8025ef05c148966f384a4d014824.zip |
habanalabs: move relevant datapath work outside cs lock
In order to shorten the time cs lock is being held, we move any
possible work outside of the cs lock.
Signed-off-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
Diffstat (limited to 'drivers/misc/habanalabs')
-rw-r--r-- | drivers/misc/habanalabs/common/command_submission.c | 86 | ||||
-rw-r--r-- | drivers/misc/habanalabs/common/device.c | 13 | ||||
-rw-r--r-- | drivers/misc/habanalabs/common/habanalabs.h | 4 |
3 files changed, 68 insertions, 35 deletions
diff --git a/drivers/misc/habanalabs/common/command_submission.c b/drivers/misc/habanalabs/common/command_submission.c index 720588aed28b..ba6d3e317255 100644 --- a/drivers/misc/habanalabs/common/command_submission.c +++ b/drivers/misc/habanalabs/common/command_submission.c @@ -84,6 +84,38 @@ int hl_gen_sob_mask(u16 sob_base, u8 sob_mask, u8 *mask) return 0; } +static void sob_reset_work(struct work_struct *work) +{ + struct hl_cs_compl *hl_cs_cmpl = + container_of(work, struct hl_cs_compl, sob_reset_work); + struct hl_device *hdev = hl_cs_cmpl->hdev; + + /* + * A signal CS can get completion while the corresponding wait + * for signal CS is on its way to the PQ. The wait for signal CS + * will get stuck if the signal CS incremented the SOB to its + * max value and there are no pending (submitted) waits on this + * SOB. + * We do the following to void this situation: + * 1. The wait for signal CS must get a ref for the signal CS as + * soon as possible in cs_ioctl_signal_wait() and put it + * before being submitted to the PQ but after it incremented + * the SOB refcnt in init_signal_wait_cs(). + * 2. Signal/Wait for signal CS will decrement the SOB refcnt + * here. + * These two measures guarantee that the wait for signal CS will + * reset the SOB upon completion rather than the signal CS and + * hence the above scenario is avoided. + */ + kref_put(&hl_cs_cmpl->hw_sob->kref, hl_sob_reset); + + if (hl_cs_cmpl->type == CS_TYPE_COLLECTIVE_WAIT) + hdev->asic_funcs->reset_sob_group(hdev, + hl_cs_cmpl->sob_group); + + kfree(hl_cs_cmpl); +} + static void hl_fence_release(struct kref *kref) { struct hl_fence *fence = @@ -109,28 +141,9 @@ static void hl_fence_release(struct kref *kref) hl_cs_cmpl->hw_sob->sob_id, hl_cs_cmpl->sob_val); - /* - * A signal CS can get completion while the corresponding wait - * for signal CS is on its way to the PQ. The wait for signal CS - * will get stuck if the signal CS incremented the SOB to its - * max value and there are no pending (submitted) waits on this - * SOB. - * We do the following to void this situation: - * 1. The wait for signal CS must get a ref for the signal CS as - * soon as possible in cs_ioctl_signal_wait() and put it - * before being submitted to the PQ but after it incremented - * the SOB refcnt in init_signal_wait_cs(). - * 2. Signal/Wait for signal CS will decrement the SOB refcnt - * here. - * These two measures guarantee that the wait for signal CS will - * reset the SOB upon completion rather than the signal CS and - * hence the above scenario is avoided. - */ - kref_put(&hl_cs_cmpl->hw_sob->kref, hl_sob_reset); + queue_work(hdev->sob_reset_wq, &hl_cs_cmpl->sob_reset_work); - if (hl_cs_cmpl->type == CS_TYPE_COLLECTIVE_WAIT) - hdev->asic_funcs->reset_sob_group(hdev, - hl_cs_cmpl->sob_group); + return; } free: @@ -670,9 +683,23 @@ static int allocate_cs(struct hl_device *hdev, struct hl_ctx *ctx, goto free_cs; } + cs->jobs_in_queue_cnt = kcalloc(hdev->asic_prop.max_queues, + sizeof(*cs->jobs_in_queue_cnt), GFP_ATOMIC); + if (!cs->jobs_in_queue_cnt) + cs->jobs_in_queue_cnt = kcalloc(hdev->asic_prop.max_queues, + sizeof(*cs->jobs_in_queue_cnt), GFP_KERNEL); + + if (!cs->jobs_in_queue_cnt) { + atomic64_inc(&ctx->cs_counters.out_of_mem_drop_cnt); + atomic64_inc(&cntr->out_of_mem_drop_cnt); + rc = -ENOMEM; + goto free_cs_cmpl; + } + cs_cmpl->hdev = hdev; cs_cmpl->type = cs->type; spin_lock_init(&cs_cmpl->lock); + INIT_WORK(&cs_cmpl->sob_reset_work, sob_reset_work); cs->fence = &cs_cmpl->base_fence; spin_lock(&ctx->cs_lock); @@ -702,19 +729,6 @@ static int allocate_cs(struct hl_device *hdev, struct hl_ctx *ctx, goto free_fence; } - cs->jobs_in_queue_cnt = kcalloc(hdev->asic_prop.max_queues, - sizeof(*cs->jobs_in_queue_cnt), GFP_ATOMIC); - if (!cs->jobs_in_queue_cnt) - cs->jobs_in_queue_cnt = kcalloc(hdev->asic_prop.max_queues, - sizeof(*cs->jobs_in_queue_cnt), GFP_KERNEL); - - if (!cs->jobs_in_queue_cnt) { - atomic64_inc(&ctx->cs_counters.out_of_mem_drop_cnt); - atomic64_inc(&cntr->out_of_mem_drop_cnt); - rc = -ENOMEM; - goto free_fence; - } - /* init hl_fence */ hl_fence_init(&cs_cmpl->base_fence, cs_cmpl->cs_seq); @@ -737,6 +751,8 @@ static int allocate_cs(struct hl_device *hdev, struct hl_ctx *ctx, free_fence: spin_unlock(&ctx->cs_lock); + kfree(cs->jobs_in_queue_cnt); +free_cs_cmpl: kfree(cs_cmpl); free_cs: kfree(cs); @@ -759,6 +775,8 @@ void hl_cs_rollback_all(struct hl_device *hdev) int i; struct hl_cs *cs, *tmp; + flush_workqueue(hdev->sob_reset_wq); + /* flush all completions before iterating over the CS mirror list in * order to avoid a race with the release functions */ diff --git a/drivers/misc/habanalabs/common/device.c b/drivers/misc/habanalabs/common/device.c index e22df6824bc3..53bc5ccb612f 100644 --- a/drivers/misc/habanalabs/common/device.c +++ b/drivers/misc/habanalabs/common/device.c @@ -368,11 +368,19 @@ static int device_early_init(struct hl_device *hdev) goto free_cq_wq; } + hdev->sob_reset_wq = alloc_workqueue("hl-sob-reset", WQ_UNBOUND, 0); + if (!hdev->sob_reset_wq) { + dev_err(hdev->dev, + "Failed to allocate SOB reset workqueue\n"); + rc = -ENOMEM; + goto free_eq_wq; + } + hdev->hl_chip_info = kzalloc(sizeof(struct hwmon_chip_info), GFP_KERNEL); if (!hdev->hl_chip_info) { rc = -ENOMEM; - goto free_eq_wq; + goto free_sob_reset_wq; } hdev->idle_busy_ts_arr = kmalloc_array(HL_IDLE_BUSY_TS_ARR_SIZE, @@ -418,6 +426,8 @@ free_idle_busy_ts_arr: kfree(hdev->idle_busy_ts_arr); free_chip_info: kfree(hdev->hl_chip_info); +free_sob_reset_wq: + destroy_workqueue(hdev->sob_reset_wq); free_eq_wq: destroy_workqueue(hdev->eq_wq); free_cq_wq: @@ -454,6 +464,7 @@ static void device_early_fini(struct hl_device *hdev) kfree(hdev->idle_busy_ts_arr); kfree(hdev->hl_chip_info); + destroy_workqueue(hdev->sob_reset_wq); destroy_workqueue(hdev->eq_wq); destroy_workqueue(hdev->device_reset_work.wq); diff --git a/drivers/misc/habanalabs/common/habanalabs.h b/drivers/misc/habanalabs/common/habanalabs.h index 2dcefd6485e5..65f34918faed 100644 --- a/drivers/misc/habanalabs/common/habanalabs.h +++ b/drivers/misc/habanalabs/common/habanalabs.h @@ -528,6 +528,7 @@ struct hl_fence { /** * struct hl_cs_compl - command submission completion object. + * @sob_reset_work: workqueue object to run SOB reset flow. * @base_fence: hl fence object. * @lock: spinlock to protect fence. * @hdev: habanalabs device structure. @@ -538,6 +539,7 @@ struct hl_fence { * @sob_group: the SOB group that is used in this collective wait CS. */ struct hl_cs_compl { + struct work_struct sob_reset_work; struct hl_fence base_fence; spinlock_t lock; struct hl_device *hdev; @@ -1905,6 +1907,7 @@ struct hl_mmu_funcs { * @cq_wq: work queues of completion queues for executing work in process * context. * @eq_wq: work queue of event queue for executing work in process context. + * @sob_reset_wq: work queue for sob reset executions. * @kernel_ctx: Kernel driver context structure. * @kernel_queues: array of hl_hw_queue. * @cs_mirror_list: CS mirror list for TDR. @@ -2022,6 +2025,7 @@ struct hl_device { struct hl_user_interrupt common_user_interrupt; struct workqueue_struct **cq_wq; struct workqueue_struct *eq_wq; + struct workqueue_struct *sob_reset_wq; struct hl_ctx *kernel_ctx; struct hl_hw_queue *kernel_queues; struct list_head cs_mirror_list; |