diff options
author | Matthew R. Ochs <mrochs@linux.vnet.ibm.com> | 2015-10-21 15:13:21 -0500 |
---|---|---|
committer | James Bottomley <JBottomley@Odin.com> | 2015-10-30 17:10:38 +0900 |
commit | 018d1dc9558e748e271cd1600c698f68cba3fb09 (patch) | |
tree | 7e3a85a14b1a516620e222bd13a3e44d24408049 /drivers/scsi/cxlflash/main.c | |
parent | 4392ba49eb248868afb412ea147ab16e2e606d66 (diff) |
cxlflash: Fix to avoid stall while waiting on TMF
Borrowing the TMF waitq's spinlock causes a stall condition when
waiting for the TMF to complete. To remedy, introduce our own spin
lock to serialize TMF and use the appropriate wait services.
Also add a timeout while waiting for a TMF completion. When a TMF
times out, report back a failure such that a bigger hammer reset
can occur.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Diffstat (limited to 'drivers/scsi/cxlflash/main.c')
-rw-r--r-- | drivers/scsi/cxlflash/main.c | 55 |
1 files changed, 33 insertions, 22 deletions
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 527ff85467ed..110037d6a1b6 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -249,11 +249,10 @@ static void cmd_complete(struct afu_cmd *cmd) scp->scsi_done(scp); if (cmd_is_tmf) { - spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + spin_lock_irqsave(&cfg->tmf_slock, lock_flags); cfg->tmf_active = false; wake_up_all_locked(&cfg->tmf_waitq); - spin_unlock_irqrestore(&cfg->tmf_waitq.lock, - lock_flags); + spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); } } else complete(&cmd->cevent); @@ -420,6 +419,7 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) struct device *dev = &cfg->dev->dev; ulong lock_flags; int rc = 0; + ulong to; cmd = cmd_checkout(afu); if (unlikely(!cmd)) { @@ -428,15 +428,15 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) goto out; } - /* If a Task Management Function is active, do not send one more. - */ - spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + /* When Task Management Function is active do not send another */ + spin_lock_irqsave(&cfg->tmf_slock, lock_flags); if (cfg->tmf_active) - wait_event_interruptible_locked_irq(cfg->tmf_waitq, - !cfg->tmf_active); + wait_event_interruptible_lock_irq(cfg->tmf_waitq, + !cfg->tmf_active, + cfg->tmf_slock); cfg->tmf_active = true; cmd->cmd_tmf = true; - spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); cmd->rcb.ctx_id = afu->ctx_hndl; cmd->rcb.port_sel = port_sel; @@ -457,15 +457,24 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) rc = send_cmd(afu, cmd); if (unlikely(rc)) { cmd_checkin(cmd); - spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + spin_lock_irqsave(&cfg->tmf_slock, lock_flags); cfg->tmf_active = false; - spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); goto out; } - spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); - wait_event_interruptible_locked_irq(cfg->tmf_waitq, !cfg->tmf_active); - spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + spin_lock_irqsave(&cfg->tmf_slock, lock_flags); + to = msecs_to_jiffies(5000); + to = wait_event_interruptible_lock_irq_timeout(cfg->tmf_waitq, + !cfg->tmf_active, + cfg->tmf_slock, + to); + if (!to) { + cfg->tmf_active = false; + dev_err(dev, "%s: TMF timed out!\n", __func__); + rc = -1; + } + spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); out: return rc; } @@ -512,16 +521,17 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) get_unaligned_be32(&((u32 *)scp->cmnd)[2]), get_unaligned_be32(&((u32 *)scp->cmnd)[3])); - /* If a Task Management Function is active, wait for it to complete + /* + * If a Task Management Function is active, wait for it to complete * before continuing with regular commands. */ - spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + spin_lock_irqsave(&cfg->tmf_slock, lock_flags); if (cfg->tmf_active) { - spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); rc = SCSI_MLQUEUE_HOST_BUSY; goto out; } - spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); switch (cfg->state) { case STATE_RESET: @@ -713,11 +723,12 @@ static void cxlflash_remove(struct pci_dev *pdev) /* If a Task Management Function is active, wait for it to complete * before continuing with remove. */ - spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + spin_lock_irqsave(&cfg->tmf_slock, lock_flags); if (cfg->tmf_active) - wait_event_interruptible_locked_irq(cfg->tmf_waitq, - !cfg->tmf_active); - spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + wait_event_interruptible_lock_irq(cfg->tmf_waitq, + !cfg->tmf_active, + cfg->tmf_slock); + spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); cfg->state = STATE_FAILTERM; cxlflash_stop_term_user_contexts(cfg); |