habanalabs: fix race between soft reset and heartbeat

There is a scenario where an ongoing soft reset would race with an
ongoing heartbeat routine, eventually causing heartbeat to fail and
thus to escalate into a hard reset.

With this fix, soft-reset procedure will disable heartbeat CPU messages
and flush the (ongoing) current one before continuing with reset code.

Signed-off-by: Koby Elbaz <kelbaz@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
This commit is contained in:
Koby Elbaz 2021-07-06 20:50:33 +03:00 committed by Oded Gabbay
parent ae2021d320
commit 8bb8b50576
4 changed files with 67 additions and 80 deletions

View File

@ -682,6 +682,44 @@ out:
return rc;
}
static void take_release_locks(struct hl_device *hdev)
{
/* Flush anyone that is inside the critical section of enqueue
* jobs to the H/W
*/
hdev->asic_funcs->hw_queues_lock(hdev);
hdev->asic_funcs->hw_queues_unlock(hdev);
/* Flush processes that are sending message to CPU */
mutex_lock(&hdev->send_cpu_message_lock);
mutex_unlock(&hdev->send_cpu_message_lock);
/* Flush anyone that is inside device open */
mutex_lock(&hdev->fpriv_list_lock);
mutex_unlock(&hdev->fpriv_list_lock);
}
static void cleanup_resources(struct hl_device *hdev, bool hard_reset)
{
if (hard_reset)
device_late_fini(hdev);
/*
* Halt the engines and disable interrupts so we won't get any more
* completions from H/W and we won't have any accesses from the
* H/W to the host machine
*/
hdev->asic_funcs->halt_engines(hdev, hard_reset);
/* Go over all the queues, release all CS and their jobs */
hl_cs_rollback_all(hdev);
/* Release all pending user interrupts, each pending user interrupt
* holds a reference to user context
*/
hl_release_pending_user_interrupts(hdev);
}
/*
* hl_device_suspend - initiate device suspend
*
@ -707,16 +745,7 @@ int hl_device_suspend(struct hl_device *hdev)
/* This blocks all other stuff that is not blocked by in_reset */
hdev->disabled = true;
/*
* Flush anyone that is inside the critical section of enqueue
* jobs to the H/W
*/
hdev->asic_funcs->hw_queues_lock(hdev);
hdev->asic_funcs->hw_queues_unlock(hdev);
/* Flush processes that are sending message to CPU */
mutex_lock(&hdev->send_cpu_message_lock);
mutex_unlock(&hdev->send_cpu_message_lock);
take_release_locks(hdev);
rc = hdev->asic_funcs->suspend(hdev);
if (rc)
@ -871,48 +900,6 @@ static void device_disable_open_processes(struct hl_device *hdev)
mutex_unlock(&hdev->fpriv_list_lock);
}
static void take_release_locks(struct hl_device *hdev)
{
/* Flush anyone that is inside the critical section of enqueue
* jobs to the H/W
*/
hdev->asic_funcs->hw_queues_lock(hdev);
hdev->asic_funcs->hw_queues_unlock(hdev);
/* Flush anyone that is inside device open */
mutex_lock(&hdev->fpriv_list_lock);
mutex_unlock(&hdev->fpriv_list_lock);
}
static void cleanup_resources(struct hl_device *hdev, bool hard_reset)
{
if (hard_reset) {
device_late_fini(hdev);
/*
* Now that the heartbeat thread is closed, flush processes
* which are sending messages to CPU
*/
mutex_lock(&hdev->send_cpu_message_lock);
mutex_unlock(&hdev->send_cpu_message_lock);
}
/*
* Halt the engines and disable interrupts so we won't get any more
* completions from H/W and we won't have any accesses from the
* H/W to the host machine
*/
hdev->asic_funcs->halt_engines(hdev, hard_reset);
/* Go over all the queues, release all CS and their jobs */
hl_cs_rollback_all(hdev);
/* Release all pending user interrupts, each pending user interrupt
* holds a reference to user context
*/
hl_release_pending_user_interrupts(hdev);
}
/*
* hl_device_reset - reset the device
*
@ -941,8 +928,8 @@ int hl_device_reset(struct hl_device *hdev, u32 flags)
return 0;
}
hard_reset = (flags & HL_RESET_HARD) != 0;
from_hard_reset_thread = (flags & HL_RESET_FROM_RESET_THREAD) != 0;
hard_reset = !!(flags & HL_RESET_HARD);
from_hard_reset_thread = !!(flags & HL_RESET_FROM_RESET_THREAD);
if (!hard_reset && !hdev->supports_soft_reset) {
hard_instead_soft = true;

View File

@ -240,11 +240,15 @@ int hl_fw_send_cpu_message(struct hl_device *hdev, u32 hw_queue_id, u32 *msg,
/* set fence to a non valid value */
pkt->fence = cpu_to_le32(UINT_MAX);
rc = hl_hw_queue_send_cb_no_cmpl(hdev, hw_queue_id, len, pkt_dma_addr);
if (rc) {
dev_err(hdev->dev, "Failed to send CB on CPU PQ (%d)\n", rc);
goto out;
}
/*
* The CPU queue is a synchronous queue with an effective depth of
* a single entry (although it is allocated with room for multiple
* entries). We lock on it using 'send_cpu_message_lock' which
* serializes accesses to the CPU queue.
* Which means that we don't need to lock the access to the entire H/W
* queues module when submitting a JOB to the CPU queue.
*/
hl_hw_queue_submit_bd(hdev, queue, 0, len, pkt_dma_addr);
if (prop->fw_app_cpu_boot_dev_sts0 & CPU_BOOT_DEV_STS0_PKT_PI_ACK_EN)
expected_ack_val = queue->pi;
@ -2235,6 +2239,10 @@ static int hl_fw_dynamic_init_cpu(struct hl_device *hdev,
dev_info(hdev->dev,
"Loading firmware to device, may take some time...\n");
/*
* In this stage, "cpu_dyn_regs" contains only LKD's hard coded values!
* It will be updated from FW after hl_fw_dynamic_request_descriptor().
*/
dyn_regs = &fw_loader->dynamic_loader.comm_desc.cpu_dyn_regs;
rc = hl_fw_dynamic_send_protocol_cmd(hdev, fw_loader, COMMS_RST_STATE,

View File

@ -2609,7 +2609,9 @@ void destroy_hdev(struct hl_device *hdev);
int hl_hw_queues_create(struct hl_device *hdev);
void hl_hw_queues_destroy(struct hl_device *hdev);
int hl_hw_queue_send_cb_no_cmpl(struct hl_device *hdev, u32 hw_queue_id,
u32 cb_size, u64 cb_ptr);
u32 cb_size, u64 cb_ptr);
void hl_hw_queue_submit_bd(struct hl_device *hdev, struct hl_hw_queue *q,
u32 ctl, u32 len, u64 ptr);
int hl_hw_queue_schedule_cs(struct hl_cs *cs);
u32 hl_hw_queue_add_ptr(u32 ptr, u16 val);
void hl_hw_queue_inc_ci_kernel(struct hl_device *hdev, u32 hw_queue_id);

View File

@ -65,7 +65,7 @@ void hl_hw_queue_update_ci(struct hl_cs *cs)
}
/*
* ext_and_hw_queue_submit_bd() - Submit a buffer descriptor to an external or a
* hl_hw_queue_submit_bd() - Submit a buffer descriptor to an external or a
* H/W queue.
* @hdev: pointer to habanalabs device structure
* @q: pointer to habanalabs queue structure
@ -80,8 +80,8 @@ void hl_hw_queue_update_ci(struct hl_cs *cs)
* This function must be called when the scheduler mutex is taken
*
*/
static void ext_and_hw_queue_submit_bd(struct hl_device *hdev,
struct hl_hw_queue *q, u32 ctl, u32 len, u64 ptr)
void hl_hw_queue_submit_bd(struct hl_device *hdev, struct hl_hw_queue *q,
u32 ctl, u32 len, u64 ptr)
{
struct hl_bd *bd;
@ -222,8 +222,8 @@ static int hw_queue_sanity_checks(struct hl_device *hdev, struct hl_hw_queue *q,
* @cb_size: size of CB
* @cb_ptr: pointer to CB location
*
* This function sends a single CB, that must NOT generate a completion entry
*
* This function sends a single CB, that must NOT generate a completion entry.
* Sending CPU messages can be done instead via 'hl_hw_queue_submit_bd()'
*/
int hl_hw_queue_send_cb_no_cmpl(struct hl_device *hdev, u32 hw_queue_id,
u32 cb_size, u64 cb_ptr)
@ -231,16 +231,7 @@ int hl_hw_queue_send_cb_no_cmpl(struct hl_device *hdev, u32 hw_queue_id,
struct hl_hw_queue *q = &hdev->kernel_queues[hw_queue_id];
int rc = 0;
/*
* The CPU queue is a synchronous queue with an effective depth of
* a single entry (although it is allocated with room for multiple
* entries). Therefore, there is a different lock, called
* send_cpu_message_lock, that serializes accesses to the CPU queue.
* As a result, we don't need to lock the access to the entire H/W
* queues module when submitting a JOB to the CPU queue
*/
if (q->queue_type != QUEUE_TYPE_CPU)
hdev->asic_funcs->hw_queues_lock(hdev);
hdev->asic_funcs->hw_queues_lock(hdev);
if (hdev->disabled) {
rc = -EPERM;
@ -258,11 +249,10 @@ int hl_hw_queue_send_cb_no_cmpl(struct hl_device *hdev, u32 hw_queue_id,
goto out;
}
ext_and_hw_queue_submit_bd(hdev, q, 0, cb_size, cb_ptr);
hl_hw_queue_submit_bd(hdev, q, 0, cb_size, cb_ptr);
out:
if (q->queue_type != QUEUE_TYPE_CPU)
hdev->asic_funcs->hw_queues_unlock(hdev);
hdev->asic_funcs->hw_queues_unlock(hdev);
return rc;
}
@ -328,7 +318,7 @@ static void ext_queue_schedule_job(struct hl_cs_job *job)
cq->pi = hl_cq_inc_ptr(cq->pi);
submit_bd:
ext_and_hw_queue_submit_bd(hdev, q, ctl, len, ptr);
hl_hw_queue_submit_bd(hdev, q, ctl, len, ptr);
}
/*
@ -407,7 +397,7 @@ static void hw_queue_schedule_job(struct hl_cs_job *job)
else
ptr = (u64) (uintptr_t) job->user_cb;
ext_and_hw_queue_submit_bd(hdev, q, ctl, len, ptr);
hl_hw_queue_submit_bd(hdev, q, ctl, len, ptr);
}
static int init_signal_cs(struct hl_device *hdev,