From d26ab06ede83287f99067fee3034c5455a75faf9 Mon Sep 17 00:00:00 2001 From: Swen Schillig Date: Mon, 19 May 2008 12:17:37 +0200 Subject: [SCSI] zfcp: receiving an unsolicted status can lead to I/O stall Processing of an unsolicted status request can lead to a locking race of the request_queue's queue_lock during the recreation of the used up status read request while still in interrupt context of the response handler. Detaching the 'refill' of the long running status read requests from the handler to a scheduled work is solving this issue. In addition, each refill-run is trying to re-establish the full amount of status read requests, which might have failed in earlier runs. Signed-off-by: Swen Schillig Signed-off-by: Christof Schmitt Signed-off-by: James Bottomley --- drivers/s390/scsi/zfcp_def.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/s390/scsi/zfcp_def.h') diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h index 306fcd0cae3..adfbbb07448 100644 --- a/drivers/s390/scsi/zfcp_def.h +++ b/drivers/s390/scsi/zfcp_def.h @@ -136,7 +136,6 @@ zfcp_address_to_sg(void *address, struct scatterlist *list, unsigned int size) #define ZFCP_QTCB_VERSION FSF_QTCB_CURRENT_VERSION /* ATTENTION: value must not be used by hardware */ #define FSF_QTCB_UNSOLICITED_STATUS 0x6305 -#define ZFCP_STATUS_READ_FAILED_THRESHOLD 3 #define ZFCP_STATUS_READS_RECOM FSF_STATUS_READS_RECOM /* Do 1st retry in 1 second, then double the timeout for each following retry */ @@ -759,7 +758,8 @@ struct zfcp_adapter { rwlock_t abort_lock; /* Protects against SCSI stack abort/command completion races */ - u16 status_read_failed; /* # failed status reads */ + atomic_t stat_miss; /* # missing status reads*/ + struct work_struct stat_work; atomic_t status; /* status of this adapter */ struct list_head erp_ready_head; /* error recovery for this adapter/devices */ -- cgit v1.2.3