diff options
Diffstat (limited to 'drivers/scsi/hpsa.c')
| -rw-r--r-- | drivers/scsi/hpsa.c | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 9acfce3bbe78..9fbc6f9120ac 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -3483,9 +3483,11 @@ static void start_io(struct ctlr_info *h) c = list_entry(h->reqQ.next, struct CommandList, list); /* can't do anything if fifo is full */ if ((h->access.fifo_full(h))) { + h->fifo_recently_full = 1; dev_warn(&h->pdev->dev, "fifo full\n"); break; } + h->fifo_recently_full = 0; /* Get the first entry from the Request Q */ removeQ(c); @@ -3539,15 +3541,41 @@ static inline int bad_tag(struct ctlr_info *h, u32 tag_index, static inline void finish_cmd(struct CommandList *c) { unsigned long flags; + int io_may_be_stalled = 0; + struct ctlr_info *h = c->h; - spin_lock_irqsave(&c->h->lock, flags); + spin_lock_irqsave(&h->lock, flags); removeQ(c); - spin_unlock_irqrestore(&c->h->lock, flags); + + /* + * Check for possibly stalled i/o. + * + * If a fifo_full condition is encountered, requests will back up + * in h->reqQ. This queue is only emptied out by start_io which is + * only called when a new i/o request comes in. If no i/o's are + * forthcoming, the i/o's in h->reqQ can get stuck. So we call + * start_io from here if we detect such a danger. + * + * Normally, we shouldn't hit this case, but pounding on the + * CCISS_PASSTHRU ioctl can provoke it. Only call start_io if + * commands_outstanding is low. We want to avoid calling + * start_io from in here as much as possible, and esp. don't + * want to get in a cycle where we call start_io every time + * through here. + */ + if (unlikely(h->fifo_recently_full) && + h->commands_outstanding < 5) + io_may_be_stalled = 1; + + spin_unlock_irqrestore(&h->lock, flags); + dial_up_lockup_detection_on_fw_flash_complete(c->h, c); if (likely(c->cmd_type == CMD_SCSI)) complete_scsi_command(c); else if (c->cmd_type == CMD_IOCTL_PEND) complete(c->waiting); + if (unlikely(io_may_be_stalled)) + start_io(h); } static inline u32 hpsa_tag_contains_index(u32 tag) |