* [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic I/O timeout @ 2013-10-04 19:38 K. Y. Srinivasan 2013-10-04 21:42 ` James Bottomley 0 siblings, 1 reply; 5+ messages in thread From: K. Y. Srinivasan @ 2013-10-04 19:38 UTC (permalink / raw) To: gregkh, linux-kernel, devel, ohering, jbottomley, hch, eric, nab, linux-scsi Cc: K. Y. Srinivasan Rather than having a separate constant for specifying the timeout on FLUSH operations, use the basic I/O timeout value that is already configurable on a per target basis to derive the FLUSH timeout. Looking at the current definitions of these timeout values, the FLUSH operation is supposed to have a value that is twice the normal timeout value. This patch preserves this relationship while leveraging the flexibility of specifying the I/O timeout. I would like to thank Eric Seppanen <eric@purestorage.com> and Nicholas A. Bellinger <nab@linux-iscsi.org> for their help in resolving this issue. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> --- drivers/scsi/sd.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index e62d17d..8aff306 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct scsi_device *sdp, struct request *rq) static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq) { - rq->timeout = SD_FLUSH_TIMEOUT; + rq->timeout *= 2; rq->retries = SD_MAX_RETRIES; rq->cmd[0] = SYNCHRONIZE_CACHE; rq->cmd_len = 10; @@ -1433,6 +1433,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) { int retries, res; struct scsi_device *sdp = sdkp->device; + unsigned int timeout = sdp->request_queue->rq_timeout; struct scsi_sense_hdr sshdr; if (!scsi_device_online(sdp)) @@ -1448,7 +1449,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) * flush everything. */ res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, - &sshdr, SD_FLUSH_TIMEOUT, + &sshdr, timeout * 2, SD_MAX_RETRIES, NULL, REQ_PM); if (res == 0) break; -- 1.7.4.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic I/O timeout 2013-10-04 19:38 [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic I/O timeout K. Y. Srinivasan @ 2013-10-04 21:42 ` James Bottomley 2013-10-04 22:01 ` KY Srinivasan 0 siblings, 1 reply; 5+ messages in thread From: James Bottomley @ 2013-10-04 21:42 UTC (permalink / raw) To: K. Y. Srinivasan Cc: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, ohering@suse.com, hch@infradead.org, eric@purestorage.com, nab@linux-iscsi.org, linux-scsi@vger.kernel.org On Fri, 2013-10-04 at 12:38 -0700, K. Y. Srinivasan wrote: > Rather than having a separate constant for specifying the timeout on FLUSH > operations, use the basic I/O timeout value that is already configurable > on a per target basis to derive the FLUSH timeout. Looking at the current > definitions of these timeout values, the FLUSH operation is supposed to have > a value that is twice the normal timeout value. This patch preserves this > relationship while leveraging the flexibility of specifying the I/O timeout. > > I would like to thank Eric Seppanen <eric@purestorage.com> and > Nicholas A. Bellinger <nab@linux-iscsi.org> for their help in resolving > this issue. > > Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> > --- > drivers/scsi/sd.c | 5 +++-- > 1 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > index e62d17d..8aff306 100644 > --- a/drivers/scsi/sd.c > +++ b/drivers/scsi/sd.c > @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct scsi_device *sdp, struct request *rq) > > static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq) > { > - rq->timeout = SD_FLUSH_TIMEOUT; > + rq->timeout *= 2; > rq->retries = SD_MAX_RETRIES; > rq->cmd[0] = SYNCHRONIZE_CACHE; > rq->cmd_len = 10; > @@ -1433,6 +1433,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > { > int retries, res; > struct scsi_device *sdp = sdkp->device; > + unsigned int timeout = sdp->request_queue->rq_timeout; The timeout is signed in the function prototype > struct scsi_sense_hdr sshdr; > > if (!scsi_device_online(sdp)) > @@ -1448,7 +1449,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > * flush everything. > */ > res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, > - &sshdr, SD_FLUSH_TIMEOUT, > + &sshdr, timeout * 2, > SD_MAX_RETRIES, NULL, REQ_PM); > if (res == 0) > break; Not like this, please: you now leave us with a dangling #define whose name makes you think it should be related to flushing and a couple of curious magic constants. It's almost hand crafted to confuse people reading the code. Please do it like this instead: with a comment explaining what we're doing above the #define and a name that clearly relates to the actions. James --- diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index e62d17d..5c9496d 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct scsi_device *sdp, struct request *rq) static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq) { - rq->timeout = SD_FLUSH_TIMEOUT; + rq->timeout *= SD_FLUSH_TIMEOUT_MULTIPLIER; rq->retries = SD_MAX_RETRIES; rq->cmd[0] = SYNCHRONIZE_CACHE; rq->cmd_len = 10; @@ -1433,6 +1433,8 @@ static int sd_sync_cache(struct scsi_disk *sdkp) { int retries, res; struct scsi_device *sdp = sdkp->device; + const int timeout = sdp->request_queue->rq_timeout + * SD_FLUSH_TIMEOUT_MULTIPLIER; struct scsi_sense_hdr sshdr; if (!scsi_device_online(sdp)) @@ -1448,8 +1450,8 @@ static int sd_sync_cache(struct scsi_disk *sdkp) * flush everything. */ res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, - &sshdr, SD_FLUSH_TIMEOUT, - SD_MAX_RETRIES, NULL, REQ_PM); + &sshdr, timeout, SD_MAX_RETRIES, + NULL, REQ_PM); if (res == 0) break; } diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h index 7a049de..7f7999c 100644 --- a/drivers/scsi/sd.h +++ b/drivers/scsi/sd.h @@ -13,7 +13,11 @@ */ #define SD_TIMEOUT (30 * HZ) #define SD_MOD_TIMEOUT (75 * HZ) -#define SD_FLUSH_TIMEOUT (60 * HZ) +/* + * Flush timeout is a multiplier over the standard device timeout which is + * user modifiable via sysfs but initially set to SD_TIMEOUT + */ +#define SD_FLUSH_TIMEOUT_MULTIPLIER 2 #define SD_WRITE_SAME_TIMEOUT (120 * HZ) /* ^ permalink raw reply related [flat|nested] 5+ messages in thread
* RE: [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic I/O timeout 2013-10-04 21:42 ` James Bottomley @ 2013-10-04 22:01 ` KY Srinivasan 2013-10-04 22:31 ` James Bottomley 0 siblings, 1 reply; 5+ messages in thread From: KY Srinivasan @ 2013-10-04 22:01 UTC (permalink / raw) To: James Bottomley Cc: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, ohering@suse.com, hch@infradead.org, eric@purestorage.com, nab@linux-iscsi.org, linux-scsi@vger.kernel.org > -----Original Message----- > From: James Bottomley [mailto:jbottomley@parallels.com] > Sent: Friday, October 04, 2013 2:42 PM > To: KY Srinivasan > Cc: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org; > devel@linuxdriverproject.org; ohering@suse.com; hch@infradead.org; > eric@purestorage.com; nab@linux-iscsi.org; linux-scsi@vger.kernel.org > Subject: Re: [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic > I/O timeout > > On Fri, 2013-10-04 at 12:38 -0700, K. Y. Srinivasan wrote: > > Rather than having a separate constant for specifying the timeout on FLUSH > > operations, use the basic I/O timeout value that is already configurable > > on a per target basis to derive the FLUSH timeout. Looking at the current > > definitions of these timeout values, the FLUSH operation is supposed to have > > a value that is twice the normal timeout value. This patch preserves this > > relationship while leveraging the flexibility of specifying the I/O timeout. > > > > I would like to thank Eric Seppanen <eric@purestorage.com> and > > Nicholas A. Bellinger <nab@linux-iscsi.org> for their help in resolving > > this issue. > > > > Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> > > --- > > drivers/scsi/sd.c | 5 +++-- > > 1 files changed, 3 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > > index e62d17d..8aff306 100644 > > --- a/drivers/scsi/sd.c > > +++ b/drivers/scsi/sd.c > > @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct > scsi_device *sdp, struct request *rq) > > > > static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq) > > { > > - rq->timeout = SD_FLUSH_TIMEOUT; > > + rq->timeout *= 2; > > rq->retries = SD_MAX_RETRIES; > > rq->cmd[0] = SYNCHRONIZE_CACHE; > > rq->cmd_len = 10; > > @@ -1433,6 +1433,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > { > > int retries, res; > > struct scsi_device *sdp = sdkp->device; > > + unsigned int timeout = sdp->request_queue->rq_timeout; > > The timeout is signed in the function prototype > > > struct scsi_sense_hdr sshdr; > > > > if (!scsi_device_online(sdp)) > > @@ -1448,7 +1449,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > * flush everything. > > */ > > res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, > > - &sshdr, SD_FLUSH_TIMEOUT, > > + &sshdr, timeout * 2, > > SD_MAX_RETRIES, NULL, REQ_PM); > > if (res == 0) > > break; > > Not like this, please: you now leave us with a dangling #define whose > name makes you think it should be related to flushing and a couple of > curious magic constants. It's almost hand crafted to confuse people > reading the code. > > Please do it like this instead: with a comment explaining what we're > doing above the #define and a name that clearly relates to the actions. > > James > > --- > > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > index e62d17d..5c9496d 100644 > --- a/drivers/scsi/sd.c > +++ b/drivers/scsi/sd.c > @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct scsi_device > *sdp, struct request *rq) > > static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq) > { > - rq->timeout = SD_FLUSH_TIMEOUT; > + rq->timeout *= SD_FLUSH_TIMEOUT_MULTIPLIER; > rq->retries = SD_MAX_RETRIES; > rq->cmd[0] = SYNCHRONIZE_CACHE; > rq->cmd_len = 10; > @@ -1433,6 +1433,8 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > { > int retries, res; > struct scsi_device *sdp = sdkp->device; > + const int timeout = sdp->request_queue->rq_timeout > + * SD_FLUSH_TIMEOUT_MULTIPLIER; > struct scsi_sense_hdr sshdr; > > if (!scsi_device_online(sdp)) > @@ -1448,8 +1450,8 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > * flush everything. > */ > res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, > - &sshdr, SD_FLUSH_TIMEOUT, > - SD_MAX_RETRIES, NULL, REQ_PM); > + &sshdr, timeout, SD_MAX_RETRIES, > + NULL, REQ_PM); > if (res == 0) > break; > } > diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h > index 7a049de..7f7999c 100644 > --- a/drivers/scsi/sd.h > +++ b/drivers/scsi/sd.h > @@ -13,7 +13,11 @@ > */ > #define SD_TIMEOUT (30 * HZ) > #define SD_MOD_TIMEOUT (75 * HZ) > -#define SD_FLUSH_TIMEOUT (60 * HZ) > +/* > + * Flush timeout is a multiplier over the standard device timeout which is > + * user modifiable via sysfs but initially set to SD_TIMEOUT > + */ > +#define SD_FLUSH_TIMEOUT_MULTIPLIER 2 > #define SD_WRITE_SAME_TIMEOUT (120 * HZ) > > /* Thanks James. Given that you have already made the changes you want done (in the Patch above), do you still want me to send you a fixed up patch? Regards, K. Y ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic I/O timeout 2013-10-04 22:01 ` KY Srinivasan @ 2013-10-04 22:31 ` James Bottomley 2013-10-04 22:33 ` KY Srinivasan 0 siblings, 1 reply; 5+ messages in thread From: James Bottomley @ 2013-10-04 22:31 UTC (permalink / raw) To: KY Srinivasan Cc: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, ohering@suse.com, hch@infradead.org, eric@purestorage.com, nab@linux-iscsi.org, linux-scsi@vger.kernel.org On Fri, 2013-10-04 at 22:01 +0000, KY Srinivasan wrote: > > > -----Original Message----- > > From: James Bottomley [mailto:jbottomley@parallels.com] > > Sent: Friday, October 04, 2013 2:42 PM > > To: KY Srinivasan > > Cc: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org; > > devel@linuxdriverproject.org; ohering@suse.com; hch@infradead.org; > > eric@purestorage.com; nab@linux-iscsi.org; linux-scsi@vger.kernel.org > > Subject: Re: [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic > > I/O timeout > > > > On Fri, 2013-10-04 at 12:38 -0700, K. Y. Srinivasan wrote: > > > Rather than having a separate constant for specifying the timeout on FLUSH > > > operations, use the basic I/O timeout value that is already configurable > > > on a per target basis to derive the FLUSH timeout. Looking at the current > > > definitions of these timeout values, the FLUSH operation is supposed to have > > > a value that is twice the normal timeout value. This patch preserves this > > > relationship while leveraging the flexibility of specifying the I/O timeout. > > > > > > I would like to thank Eric Seppanen <eric@purestorage.com> and > > > Nicholas A. Bellinger <nab@linux-iscsi.org> for their help in resolving > > > this issue. > > > > > > Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> > > > --- > > > drivers/scsi/sd.c | 5 +++-- > > > 1 files changed, 3 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > > > index e62d17d..8aff306 100644 > > > --- a/drivers/scsi/sd.c > > > +++ b/drivers/scsi/sd.c > > > @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct > > scsi_device *sdp, struct request *rq) > > > > > > static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq) > > > { > > > - rq->timeout = SD_FLUSH_TIMEOUT; > > > + rq->timeout *= 2; > > > rq->retries = SD_MAX_RETRIES; > > > rq->cmd[0] = SYNCHRONIZE_CACHE; > > > rq->cmd_len = 10; > > > @@ -1433,6 +1433,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > > { > > > int retries, res; > > > struct scsi_device *sdp = sdkp->device; > > > + unsigned int timeout = sdp->request_queue->rq_timeout; > > > > The timeout is signed in the function prototype > > > > > struct scsi_sense_hdr sshdr; > > > > > > if (!scsi_device_online(sdp)) > > > @@ -1448,7 +1449,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > > * flush everything. > > > */ > > > res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, > > > - &sshdr, SD_FLUSH_TIMEOUT, > > > + &sshdr, timeout * 2, > > > SD_MAX_RETRIES, NULL, REQ_PM); > > > if (res == 0) > > > break; > > > > Not like this, please: you now leave us with a dangling #define whose > > name makes you think it should be related to flushing and a couple of > > curious magic constants. It's almost hand crafted to confuse people > > reading the code. > > > > Please do it like this instead: with a comment explaining what we're > > doing above the #define and a name that clearly relates to the actions. > > > > James > > > > --- > > > > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > > index e62d17d..5c9496d 100644 > > --- a/drivers/scsi/sd.c > > +++ b/drivers/scsi/sd.c > > @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct scsi_device > > *sdp, struct request *rq) > > > > static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq) > > { > > - rq->timeout = SD_FLUSH_TIMEOUT; > > + rq->timeout *= SD_FLUSH_TIMEOUT_MULTIPLIER; > > rq->retries = SD_MAX_RETRIES; > > rq->cmd[0] = SYNCHRONIZE_CACHE; > > rq->cmd_len = 10; > > @@ -1433,6 +1433,8 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > { > > int retries, res; > > struct scsi_device *sdp = sdkp->device; > > + const int timeout = sdp->request_queue->rq_timeout > > + * SD_FLUSH_TIMEOUT_MULTIPLIER; > > struct scsi_sense_hdr sshdr; > > > > if (!scsi_device_online(sdp)) > > @@ -1448,8 +1450,8 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > * flush everything. > > */ > > res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, > > - &sshdr, SD_FLUSH_TIMEOUT, > > - SD_MAX_RETRIES, NULL, REQ_PM); > > + &sshdr, timeout, SD_MAX_RETRIES, > > + NULL, REQ_PM); > > if (res == 0) > > break; > > } > > diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h > > index 7a049de..7f7999c 100644 > > --- a/drivers/scsi/sd.h > > +++ b/drivers/scsi/sd.h > > @@ -13,7 +13,11 @@ > > */ > > #define SD_TIMEOUT (30 * HZ) > > #define SD_MOD_TIMEOUT (75 * HZ) > > -#define SD_FLUSH_TIMEOUT (60 * HZ) > > +/* > > + * Flush timeout is a multiplier over the standard device timeout which is > > + * user modifiable via sysfs but initially set to SD_TIMEOUT > > + */ > > +#define SD_FLUSH_TIMEOUT_MULTIPLIER 2 > > #define SD_WRITE_SAME_TIMEOUT (120 * HZ) > > > > /* > > Thanks James. Given that you have already made the changes you want done (in the > Patch above), do you still want me to send you a fixed up patch? Either way is fine. I just need the patch to be on the mailing list for my workflow (which it is now). James ^ permalink raw reply [flat|nested] 5+ messages in thread
* RE: [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic I/O timeout 2013-10-04 22:31 ` James Bottomley @ 2013-10-04 22:33 ` KY Srinivasan 0 siblings, 0 replies; 5+ messages in thread From: KY Srinivasan @ 2013-10-04 22:33 UTC (permalink / raw) To: James Bottomley Cc: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, ohering@suse.com, hch@infradead.org, eric@purestorage.com, nab@linux-iscsi.org, linux-scsi@vger.kernel.org > -----Original Message----- > From: James Bottomley [mailto:jbottomley@parallels.com] > Sent: Friday, October 04, 2013 3:31 PM > To: KY Srinivasan > Cc: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org; > devel@linuxdriverproject.org; ohering@suse.com; hch@infradead.org; > eric@purestorage.com; nab@linux-iscsi.org; linux-scsi@vger.kernel.org > Subject: Re: [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic > I/O timeout > > On Fri, 2013-10-04 at 22:01 +0000, KY Srinivasan wrote: > > > > > -----Original Message----- > > > From: James Bottomley [mailto:jbottomley@parallels.com] > > > Sent: Friday, October 04, 2013 2:42 PM > > > To: KY Srinivasan > > > Cc: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org; > > > devel@linuxdriverproject.org; ohering@suse.com; hch@infradead.org; > > > eric@purestorage.com; nab@linux-iscsi.org; linux-scsi@vger.kernel.org > > > Subject: Re: [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the > basic > > > I/O timeout > > > > > > On Fri, 2013-10-04 at 12:38 -0700, K. Y. Srinivasan wrote: > > > > Rather than having a separate constant for specifying the timeout on FLUSH > > > > operations, use the basic I/O timeout value that is already configurable > > > > on a per target basis to derive the FLUSH timeout. Looking at the current > > > > definitions of these timeout values, the FLUSH operation is supposed to > have > > > > a value that is twice the normal timeout value. This patch preserves this > > > > relationship while leveraging the flexibility of specifying the I/O timeout. > > > > > > > > I would like to thank Eric Seppanen <eric@purestorage.com> and > > > > Nicholas A. Bellinger <nab@linux-iscsi.org> for their help in resolving > > > > this issue. > > > > > > > > Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> > > > > --- > > > > drivers/scsi/sd.c | 5 +++-- > > > > 1 files changed, 3 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > > > > index e62d17d..8aff306 100644 > > > > --- a/drivers/scsi/sd.c > > > > +++ b/drivers/scsi/sd.c > > > > @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct > > > scsi_device *sdp, struct request *rq) > > > > > > > > static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request > *rq) > > > > { > > > > - rq->timeout = SD_FLUSH_TIMEOUT; > > > > + rq->timeout *= 2; > > > > rq->retries = SD_MAX_RETRIES; > > > > rq->cmd[0] = SYNCHRONIZE_CACHE; > > > > rq->cmd_len = 10; > > > > @@ -1433,6 +1433,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > > > { > > > > int retries, res; > > > > struct scsi_device *sdp = sdkp->device; > > > > + unsigned int timeout = sdp->request_queue->rq_timeout; > > > > > > The timeout is signed in the function prototype > > > > > > > struct scsi_sense_hdr sshdr; > > > > > > > > if (!scsi_device_online(sdp)) > > > > @@ -1448,7 +1449,7 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > > > * flush everything. > > > > */ > > > > res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, > > > > - &sshdr, SD_FLUSH_TIMEOUT, > > > > + &sshdr, timeout * 2, > > > > SD_MAX_RETRIES, NULL, REQ_PM); > > > > if (res == 0) > > > > break; > > > > > > Not like this, please: you now leave us with a dangling #define whose > > > name makes you think it should be related to flushing and a couple of > > > curious magic constants. It's almost hand crafted to confuse people > > > reading the code. > > > > > > Please do it like this instead: with a comment explaining what we're > > > doing above the #define and a name that clearly relates to the actions. > > > > > > James > > > > > > --- > > > > > > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > > > index e62d17d..5c9496d 100644 > > > --- a/drivers/scsi/sd.c > > > +++ b/drivers/scsi/sd.c > > > @@ -829,7 +829,7 @@ static int sd_setup_write_same_cmnd(struct > scsi_device > > > *sdp, struct request *rq) > > > > > > static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq) > > > { > > > - rq->timeout = SD_FLUSH_TIMEOUT; > > > + rq->timeout *= SD_FLUSH_TIMEOUT_MULTIPLIER; > > > rq->retries = SD_MAX_RETRIES; > > > rq->cmd[0] = SYNCHRONIZE_CACHE; > > > rq->cmd_len = 10; > > > @@ -1433,6 +1433,8 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > > { > > > int retries, res; > > > struct scsi_device *sdp = sdkp->device; > > > + const int timeout = sdp->request_queue->rq_timeout > > > + * SD_FLUSH_TIMEOUT_MULTIPLIER; > > > struct scsi_sense_hdr sshdr; > > > > > > if (!scsi_device_online(sdp)) > > > @@ -1448,8 +1450,8 @@ static int sd_sync_cache(struct scsi_disk *sdkp) > > > * flush everything. > > > */ > > > res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, > > > - &sshdr, SD_FLUSH_TIMEOUT, > > > - SD_MAX_RETRIES, NULL, REQ_PM); > > > + &sshdr, timeout, SD_MAX_RETRIES, > > > + NULL, REQ_PM); > > > if (res == 0) > > > break; > > > } > > > diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h > > > index 7a049de..7f7999c 100644 > > > --- a/drivers/scsi/sd.h > > > +++ b/drivers/scsi/sd.h > > > @@ -13,7 +13,11 @@ > > > */ > > > #define SD_TIMEOUT (30 * HZ) > > > #define SD_MOD_TIMEOUT (75 * HZ) > > > -#define SD_FLUSH_TIMEOUT (60 * HZ) > > > +/* > > > + * Flush timeout is a multiplier over the standard device timeout which is > > > + * user modifiable via sysfs but initially set to SD_TIMEOUT > > > + */ > > > +#define SD_FLUSH_TIMEOUT_MULTIPLIER 2 > > > #define SD_WRITE_SAME_TIMEOUT (120 * HZ) > > > > > > /* > > > > Thanks James. Given that you have already made the changes you want done > (in the > > Patch above), do you still want me to send you a fixed up patch? > > Either way is fine. I just need the patch to be on the mailing list for > my workflow (which it is now). In that case, we will go with the patch you have. Thank you for taking the time on this. Regards, K. Y > > James > ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2013-10-04 22:33 UTC | newest] Thread overview: 5+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2013-10-04 19:38 [PATCH 1/1] Drivers: scsi: Derive the FLUSH_TIMEOUT from the basic I/O timeout K. Y. Srinivasan 2013-10-04 21:42 ` James Bottomley 2013-10-04 22:01 ` KY Srinivasan 2013-10-04 22:31 ` James Bottomley 2013-10-04 22:33 ` KY Srinivasan
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