Additionally, add a comment about the queuecommand() call from scsi_send_eh_cmnd(). Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> Cc: James Bottomley <jejb@xxxxxxxxxxxxxxxxxx> Cc: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Sagi Grimberg <sagi@xxxxxxxxxxx> Cc: Doug Ledford <dledford@xxxxxxxxxx> --- drivers/scsi/scsi_lib.c | 40 +++++++++++++++++++++++++++++++++++++++ drivers/scsi/scsi_transport_srp.c | 35 ++-------------------------------- include/scsi/scsi_host.h | 1 + 3 files changed, 43 insertions(+), 33 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index ab5b06f..a5a1b5d 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2722,6 +2722,46 @@ void sdev_evt_send_simple(struct scsi_device *sdev, EXPORT_SYMBOL_GPL(sdev_evt_send_simple); /** + * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn() + * @shost: SCSI host for which to count the number of scsi_request_fn() callers. + * + * To do: add support for scsi-mq in this function. + */ +static int scsi_request_fn_active(struct Scsi_Host *shost) +{ + struct scsi_device *sdev; + struct request_queue *q; + int request_fn_active = 0; + + shost_for_each_device(sdev, shost) { + q = sdev->request_queue; + + spin_lock_irq(q->queue_lock); + request_fn_active += q->request_fn_active; + spin_unlock_irq(q->queue_lock); + } + + return request_fn_active; +} + +/** + * scsi_wait_for_queuecommand() - wait for ongoing queuecommand() calls + * + * Wait until the ongoing shost->hostt->queuecommand() calls that are + * invoked from scsi_request_fn() have finished. + * + * To do: avoid that scsi_send_eh_cmnd() calls queuecommand() after + * scsi_internal_device_block() has blocked a SCSI device and remove and also + * remove the rport mutex lock and unlock calls from srp_queuecommand(). + */ +void scsi_wait_for_queuecommand(struct Scsi_Host *shost) +{ + while (scsi_request_fn_active(shost)) + msleep(20); +} +EXPORT_SYMBOL(scsi_wait_for_queuecommand); + +/** * scsi_device_quiesce - Block user issued commands. * @sdev: scsi device to quiesce. * diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c index e3cd3ec..8b190dc 100644 --- a/drivers/scsi/scsi_transport_srp.c +++ b/drivers/scsi/scsi_transport_srp.c @@ -24,7 +24,6 @@ #include <linux/err.h> #include <linux/slab.h> #include <linux/string.h> -#include <linux/delay.h> #include <scsi/scsi.h> #include <scsi/scsi_cmnd.h> @@ -402,36 +401,6 @@ static void srp_reconnect_work(struct work_struct *work) } } -/** - * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn() - * @shost: SCSI host for which to count the number of scsi_request_fn() callers. - * - * To do: add support for scsi-mq in this function. - */ -static int scsi_request_fn_active(struct Scsi_Host *shost) -{ - struct scsi_device *sdev; - struct request_queue *q; - int request_fn_active = 0; - - shost_for_each_device(sdev, shost) { - q = sdev->request_queue; - - spin_lock_irq(q->queue_lock); - request_fn_active += q->request_fn_active; - spin_unlock_irq(q->queue_lock); - } - - return request_fn_active; -} - -/* Wait until ongoing shost->hostt->queuecommand() calls have finished. */ -static void srp_wait_for_queuecommand(struct Scsi_Host *shost) -{ - while (scsi_request_fn_active(shost)) - msleep(20); -} - static void __rport_fail_io_fast(struct srp_rport *rport) { struct Scsi_Host *shost = rport_to_shost(rport); @@ -446,7 +415,7 @@ static void __rport_fail_io_fast(struct srp_rport *rport) /* Involve the LLD if possible to terminate all I/O on the rport. */ i = to_srp_internal(shost->transportt); if (i->f->terminate_rport_io) { - srp_wait_for_queuecommand(shost); + scsi_wait_for_queuecommand(shost); i->f->terminate_rport_io(rport); } } @@ -576,7 +545,7 @@ int srp_reconnect_rport(struct srp_rport *rport) if (res) goto out; scsi_target_block(&shost->shost_gendev); - srp_wait_for_queuecommand(shost); + scsi_wait_for_queuecommand(shost); res = rport->state != SRP_RPORT_LOST ? i->f->reconnect(rport) : -ENODEV; pr_debug("%s (state %d): transport.reconnect() returned %d\n", dev_name(&shost->shost_gendev), rport->state, res); diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 7e4cd53..0e2c361 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -789,6 +789,7 @@ extern void scsi_remove_host(struct Scsi_Host *); extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *); extern void scsi_host_put(struct Scsi_Host *t); extern struct Scsi_Host *scsi_host_lookup(unsigned short); +extern void scsi_wait_for_queuecommand(struct Scsi_Host *shost); extern const char *scsi_host_state_name(enum scsi_host_state); extern void scsi_cmd_get_serial(struct Scsi_Host *, struct scsi_cmnd *); -- 2.10.1 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html