blk-mq: move failure injection out of blk_mq_complete_request

Move the call to blk_should_fake_timeout out of blk_mq_complete_request
and into the drivers, skipping call sites that are obvious error
handlers, and remove the now superflous blk_mq_force_complete_rq helper.
This ensures we don't keep injecting errors into completions that just
terminate the Linux request after the hardware has been reset or the
command has been aborted.

Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2020-06-11 08:44:47 +02:00 committed by Jens Axboe
parent d391a7a399
commit 15f73f5b3e
19 changed files with 61 additions and 72 deletions

View File

@ -655,16 +655,13 @@ static void __blk_mq_complete_request_remote(void *data)
}
/**
* blk_mq_force_complete_rq() - Force complete the request, bypassing any error
* injection that could drop the completion.
* @rq: Request to be force completed
* blk_mq_complete_request - end I/O on a request
* @rq: the request being processed
*
* Drivers should use blk_mq_complete_request() to complete requests in their
* normal IO path. For timeout error recovery, drivers may call this forced
* completion routine after they've reclaimed timed out requests to bypass
* potentially subsequent fake timeouts.
*/
void blk_mq_force_complete_rq(struct request *rq)
* Description:
* Complete a request by scheduling the ->complete_rq operation.
**/
void blk_mq_complete_request(struct request *rq)
{
struct blk_mq_ctx *ctx = rq->mq_ctx;
struct request_queue *q = rq->q;
@ -702,7 +699,7 @@ void blk_mq_force_complete_rq(struct request *rq)
}
put_cpu();
}
EXPORT_SYMBOL_GPL(blk_mq_force_complete_rq);
EXPORT_SYMBOL(blk_mq_complete_request);
static void hctx_unlock(struct blk_mq_hw_ctx *hctx, int srcu_idx)
__releases(hctx->srcu)
@ -724,23 +721,6 @@ static void hctx_lock(struct blk_mq_hw_ctx *hctx, int *srcu_idx)
*srcu_idx = srcu_read_lock(hctx->srcu);
}
/**
* blk_mq_complete_request - end I/O on a request
* @rq: the request being processed
*
* Description:
* Ends all I/O on a request. It does not handle partial completions.
* The actual completion happens out-of-order, through a IPI handler.
**/
bool blk_mq_complete_request(struct request *rq)
{
if (unlikely(blk_should_fake_timeout(rq->q)))
return false;
blk_mq_force_complete_rq(rq);
return true;
}
EXPORT_SYMBOL(blk_mq_complete_request);
/**
* blk_mq_start_request - Start processing a request
* @rq: Pointer to request to be started

View File

@ -20,13 +20,11 @@ static int __init setup_fail_io_timeout(char *str)
}
__setup("fail_io_timeout=", setup_fail_io_timeout);
int blk_should_fake_timeout(struct request_queue *q)
bool __blk_should_fake_timeout(struct request_queue *q)
{
if (!test_bit(QUEUE_FLAG_FAIL_IO, &q->queue_flags))
return 0;
return should_fail(&fail_io_timeout, 1);
}
EXPORT_SYMBOL_GPL(__blk_should_fake_timeout);
static int __init fail_io_timeout_debugfs(void)
{

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@ -223,18 +223,9 @@ ssize_t part_fail_show(struct device *dev, struct device_attribute *attr,
char *buf);
ssize_t part_fail_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count);
#ifdef CONFIG_FAIL_IO_TIMEOUT
int blk_should_fake_timeout(struct request_queue *);
ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
ssize_t part_timeout_store(struct device *, struct device_attribute *,
const char *, size_t);
#else
static inline int blk_should_fake_timeout(struct request_queue *q)
{
return 0;
}
#endif
void __blk_queue_split(struct request_queue *q, struct bio **bio,
unsigned int *nr_segs);

View File

@ -181,9 +181,12 @@ EXPORT_SYMBOL_GPL(bsg_job_get);
void bsg_job_done(struct bsg_job *job, int result,
unsigned int reply_payload_rcv_len)
{
struct request *rq = blk_mq_rq_from_pdu(job);
job->result = result;
job->reply_payload_rcv_len = reply_payload_rcv_len;
blk_mq_complete_request(blk_mq_rq_from_pdu(job));
if (likely(!blk_should_fake_timeout(rq->q)))
blk_mq_complete_request(rq);
}
EXPORT_SYMBOL_GPL(bsg_job_done);

View File

@ -509,7 +509,8 @@ static void lo_rw_aio_do_completion(struct loop_cmd *cmd)
return;
kfree(cmd->bvec);
cmd->bvec = NULL;
blk_mq_complete_request(rq);
if (likely(!blk_should_fake_timeout(rq->q)))
blk_mq_complete_request(rq);
}
static void lo_rw_aio_complete(struct kiocb *iocb, long ret, long ret2)
@ -2048,7 +2049,8 @@ static void loop_handle_cmd(struct loop_cmd *cmd)
cmd->ret = ret;
else
cmd->ret = ret ? -EIO : 0;
blk_mq_complete_request(rq);
if (likely(!blk_should_fake_timeout(rq->q)))
blk_mq_complete_request(rq);
}
}

View File

@ -492,7 +492,8 @@ static void mtip_complete_command(struct mtip_cmd *cmd, blk_status_t status)
struct request *req = blk_mq_rq_from_pdu(cmd);
cmd->status = status;
blk_mq_complete_request(req);
if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
}
/*

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@ -784,6 +784,7 @@ static void recv_work(struct work_struct *work)
struct nbd_device *nbd = args->nbd;
struct nbd_config *config = nbd->config;
struct nbd_cmd *cmd;
struct request *rq;
while (1) {
cmd = nbd_read_stat(nbd, args->index);
@ -796,7 +797,9 @@ static void recv_work(struct work_struct *work)
break;
}
blk_mq_complete_request(blk_mq_rq_from_pdu(cmd));
rq = blk_mq_rq_from_pdu(cmd);
if (likely(!blk_should_fake_timeout(rq->q)))
blk_mq_complete_request(rq);
}
atomic_dec(&config->recv_threads);
wake_up(&config->recv_wq);

View File

@ -1283,7 +1283,8 @@ static inline void nullb_complete_cmd(struct nullb_cmd *cmd)
case NULL_IRQ_SOFTIRQ:
switch (cmd->nq->dev->queue_mode) {
case NULL_Q_MQ:
blk_mq_complete_request(cmd->rq);
if (likely(!blk_should_fake_timeout(cmd->rq->q)))
blk_mq_complete_request(cmd->rq);
break;
case NULL_Q_BIO:
/*
@ -1423,7 +1424,7 @@ static bool should_requeue_request(struct request *rq)
static enum blk_eh_timer_return null_timeout_rq(struct request *rq, bool res)
{
pr_info("rq %p timed out\n", rq);
blk_mq_force_complete_rq(rq);
blk_mq_complete_request(rq);
return BLK_EH_DONE;
}

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@ -1417,7 +1417,8 @@ static void skd_resolve_req_exception(struct skd_device *skdev,
case SKD_CHECK_STATUS_REPORT_GOOD:
case SKD_CHECK_STATUS_REPORT_SMART_ALERT:
skreq->status = BLK_STS_OK;
blk_mq_complete_request(req);
if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
break;
case SKD_CHECK_STATUS_BUSY_IMMINENT:
@ -1440,7 +1441,8 @@ static void skd_resolve_req_exception(struct skd_device *skdev,
case SKD_CHECK_STATUS_REPORT_ERROR:
default:
skreq->status = BLK_STS_IOERR;
blk_mq_complete_request(req);
if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
break;
}
}
@ -1560,7 +1562,8 @@ static int skd_isr_completion_posted(struct skd_device *skdev,
*/
if (likely(cmp_status == SAM_STAT_GOOD)) {
skreq->status = BLK_STS_OK;
blk_mq_complete_request(rq);
if (likely(!blk_should_fake_timeout(rq->q)))
blk_mq_complete_request(rq);
} else {
skd_resolve_req_exception(skdev, skreq, rq);
}

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@ -171,7 +171,8 @@ static void virtblk_done(struct virtqueue *vq)
while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) {
struct request *req = blk_mq_rq_from_pdu(vbr);
blk_mq_complete_request(req);
if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
req_done = true;
}
if (unlikely(virtqueue_is_broken(vq)))

View File

@ -1655,7 +1655,8 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
BUG();
}
blk_mq_complete_request(req);
if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
}
rinfo->ring.rsp_cons = i;

View File

@ -288,7 +288,8 @@ static void dm_complete_request(struct request *rq, blk_status_t error)
struct dm_rq_target_io *tio = tio_from_request(rq);
tio->error = error;
blk_mq_complete_request(rq);
if (likely(!blk_should_fake_timeout(rq->q)))
blk_mq_complete_request(rq);
}
/*

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@ -1446,7 +1446,7 @@ static void mmc_blk_cqe_req_done(struct mmc_request *mrq)
*/
if (mq->in_recovery)
mmc_blk_cqe_complete_rq(mq, req);
else
else if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
}
@ -1926,7 +1926,7 @@ static void mmc_blk_hsq_req_done(struct mmc_request *mrq)
*/
if (mq->in_recovery)
mmc_blk_cqe_complete_rq(mq, req);
else
else if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
}
@ -1936,7 +1936,7 @@ void mmc_blk_mq_complete(struct request *req)
if (mq->use_cqe)
mmc_blk_cqe_complete_rq(mq, req);
else
else if (likely(!blk_should_fake_timeout(req->q)))
mmc_blk_mq_complete_rq(mq, req);
}
@ -1988,7 +1988,7 @@ static void mmc_blk_mq_post_req(struct mmc_queue *mq, struct request *req)
*/
if (mq->in_recovery)
mmc_blk_mq_complete_rq(mq, req);
else
else if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
mmc_blk_mq_dec_in_flight(mq, req);

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@ -304,7 +304,7 @@ bool nvme_cancel_request(struct request *req, void *data, bool reserved)
return true;
nvme_req(req)->status = NVME_SC_HOST_ABORTED_CMD;
blk_mq_force_complete_rq(req);
blk_mq_complete_request(req);
return true;
}
EXPORT_SYMBOL_GPL(nvme_cancel_request);

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@ -481,7 +481,8 @@ static inline void nvme_end_request(struct request *req, __le16 status,
rq->result = result;
/* inject error when permitted by fault injection framework */
nvme_should_fail(req);
blk_mq_complete_request(req);
if (likely(!blk_should_fake_timeout(req->q)))
blk_mq_complete_request(req);
}
static inline void nvme_get_ctrl(struct nvme_ctrl *ctrl)

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@ -2802,7 +2802,7 @@ static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
blk_update_request(req, BLK_STS_OK,
blk_rq_bytes(req) - proc_bytes);
blk_mq_requeue_request(req, true);
} else {
} else if (likely(!blk_should_fake_timeout(req->q))) {
blk_mq_complete_request(req);
}
}

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@ -256,7 +256,8 @@ static void scm_request_finish(struct scm_request *scmrq)
for (i = 0; i < nr_requests_per_io && scmrq->request[i]; i++) {
error = blk_mq_rq_to_pdu(scmrq->request[i]);
*error = scmrq->error;
blk_mq_complete_request(scmrq->request[i]);
if (likely(!blk_should_fake_timeout(scmrq->request[i]->q)))
blk_mq_complete_request(scmrq->request[i]);
}
atomic_dec(&bdev->queued_reqs);

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@ -1589,18 +1589,12 @@ static blk_status_t scsi_mq_prep_fn(struct request *req)
static void scsi_mq_done(struct scsi_cmnd *cmd)
{
if (unlikely(blk_should_fake_timeout(cmd->request->q)))
return;
if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state)))
return;
trace_scsi_dispatch_cmd_done(cmd);
/*
* If the block layer didn't complete the request due to a timeout
* injection, scsi must clear its internal completed state so that the
* timeout handler will see it needs to escalate its own error
* recovery.
*/
if (unlikely(!blk_mq_complete_request(cmd->request)))
clear_bit(SCMD_STATE_COMPLETE, &cmd->state);
blk_mq_complete_request(cmd->request);
}
static void scsi_mq_put_budget(struct blk_mq_hw_ctx *hctx)

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@ -503,8 +503,7 @@ void __blk_mq_end_request(struct request *rq, blk_status_t error);
void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list);
void blk_mq_kick_requeue_list(struct request_queue *q);
void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs);
bool blk_mq_complete_request(struct request *rq);
void blk_mq_force_complete_rq(struct request *rq);
void blk_mq_complete_request(struct request *rq);
bool blk_mq_bio_list_merge(struct request_queue *q, struct list_head *list,
struct bio *bio, unsigned int nr_segs);
bool blk_mq_queue_stopped(struct request_queue *q);
@ -537,6 +536,15 @@ void blk_mq_quiesce_queue_nowait(struct request_queue *q);
unsigned int blk_mq_rq_cpu(struct request *rq);
bool __blk_should_fake_timeout(struct request_queue *q);
static inline bool blk_should_fake_timeout(struct request_queue *q)
{
if (IS_ENABLED(CONFIG_FAIL_IO_TIMEOUT) &&
test_bit(QUEUE_FLAG_FAIL_IO, &q->queue_flags))
return __blk_should_fake_timeout(q);
return false;
}
/**
* blk_mq_rq_from_pdu - cast a PDU to a request
* @pdu: the PDU (Protocol Data Unit) to be casted