[PATCH] [SCSI]: Remove Kconfig text referring to non-existent scsi_wait_scan_module
The scsi_wait_scan_module was removed in linux-3.6 with commit 6072609d9bb91ff54aee3ef29304bd5b4fc88aae Remove the text referring to it under config SCSI_SCAN_ASYNC Signed-off-by: John Kacur --- drivers/scsi/Kconfig | 7 --- 1 file changed, 7 deletions(-) diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig index fe25677..49d7768 100644 --- a/drivers/scsi/Kconfig +++ b/drivers/scsi/Kconfig @@ -253,13 +253,6 @@ config SCSI_SCAN_ASYNC system continues booting, and even probe devices on different busses in parallel, leading to a significant speed-up. - If you have built SCSI as modules, enabling this option can - be a problem as the devices may not have been found by the - time your system expects them to have been. You can load the - scsi_wait_scan module to ensure that all scans have completed. - If you build your SCSI drivers into the kernel, then everything - will work fine if you say Y here. - You can override this choice by specifying "scsi_mod.scan=sync" or async on the kernel's command line. -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] hpsa: fix warning with smp_processor_id() in preemptible
- Original Message - > * John Kacur | 2013-07-26 16:42:30 [+0200]: > > >Signed-off-by: John Kacur > >Acked-by: Stephen > > ping. > > I checked the branches for-next, scsi-fixes, fixes and misc at [0] and I > didn't see it. I'm going to take this for 3.10-rt but please don't lose > it on its way to Linus :) > > [0] git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi.git I hope it was clear to everyone that this patch was intended for upstream. It was discovered by running the real-time kernel, but it exposes a (minor) problem that should be fixed in the mainline kernel. Please apply it there Stephen, and push it upstream appropriately. Thank You. John Kacur -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH] hpsa: fix warning with smp_processor_id() in preemptible
>From 4c01ac362210c38cdbaddd0a75c24c7070e77dfa Mon Sep 17 00:00:00 2001 From: John Kacur Date: Fri, 26 Jul 2013 16:06:18 +0200 Subject: [PATCH] hpsa: fix warning with smp_processor_id() in preemptible section Signed-off-by: John Kacur On a 3.6-rt (real-time patch) kernel we are seeing the following BUG However, it appears to be relevant for non-realtime (mainline) as well. [ 49.688847] hpsa :03:00.0: hpsa0: <0x323a> at IRQ 67 using DAC [ 49.749928] scsi0 : hpsa [ 49.784437] BUG: using smp_processor_id() in preemptible [ ] code: kworker/u:0/6 [ 49.784465] caller is enqueue_cmd_and_start_io+0x5a/0x100 [hpsa] [ 49.784468] Pid: 6, comm: kworker/u:0 Not tainted 3.6.11.5-rt37.52.el6rt.x86_64.debug #1 [ 49.784471] Call Trace: [ 49.784512] [] debug_smp_processor_id+0x123/0x150 [ 49.784520] [] enqueue_cmd_and_start_io+0x5a/0x100 [hpsa] [ 49.784529] [] hpsa_scsi_do_simple_cmd_core+0xeb/0x110 [hpsa] [ 49.784537] [] ? swiotlb_dma_mapping_error+0x18/0x30 [ 49.784544] [] ? swiotlb_dma_mapping_error+0x18/0x30 [ 49.784553] [] hpsa_scsi_do_simple_cmd_with_retry+0x91/0x280 [hpsa] [ 49.784562] [] hpsa_scsi_do_report_luns.clone.2+0xd8/0x130 [hpsa] [ 49.784571] [] hpsa_gather_lun_info.clone.3+0x3a/0x1a0 [hpsa] [ 49.784580] [] hpsa_update_scsi_devices+0x11f/0x4f0 [hpsa] [ 49.784592] [] ? sub_preempt_count+0xa9/0xe0 [ 49.784601] [] hpsa_scan_start+0xfd/0x150 [hpsa] [ 49.784613] [] ? rt_spin_lock_slowunlock+0x78/0x90 [ 49.784626] [] do_scsi_scan_host+0x37/0xa0 [ 49.784632] [] do_scan_async+0x1a/0x30 [ 49.784643] [] async_run_entry_fn+0x9b/0x1d0 [ 49.784655] [] process_one_work+0x1f2/0x620 [ 49.784661] [] ? process_one_work+0x180/0x620 [ 49.784668] [] ? worker_thread+0x5e/0x3a0 [ 49.784674] [] ? async_schedule+0x20/0x20 [ 49.784681] [] worker_thread+0x133/0x3a0 [ 49.784688] [] ? manage_workers+0x190/0x190 [ 49.784696] [] kthread+0xa6/0xb0 [ 49.784707] [] kernel_thread_helper+0x4/0x10 [ 49.784715] [] ? finish_task_switch+0x8c/0x110 [ 49.784721] [] ? _raw_spin_unlock_irq+0x3b/0x70 [ 49.784727] [] ? retint_restore_args+0xe/0xe [ 49.784734] [] ? kthreadd+0x1e0/0x1e0 [ 49.784739] [] ? gs_change+0xb/0xb --- This is caused by enqueue_cmd_and_start_io()-> set_performant_mode()-> smp_processor_id() Which if you have debugging enabled calls debug_processor_id() and triggers the warning. The code here is c->Header.ReplyQueue = smp_processor_id() % h->nreply_queues; Since it is not critical that the code complete on the same processor, but the cpu is a hint used in generating the ReplyQueue and will still work if the cpu migrates or is preempted, it is safe to use the raw_smp_processor_id() to surpress the false positve warning. Signed-off-by: John Kacur Acked-by: Stephen --- drivers/scsi/hpsa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 7f4f790..4e19267 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -583,7 +583,7 @@ static void set_performant_mode(struct ctlr_info *h, struct CommandList *c) c->busaddr |= 1 | (h->blockFetchTable[c->Header.SGList] << 1); if (likely(h->msix_vector)) c->Header.ReplyQueue = - smp_processor_id() % h->nreply_queues; + raw_smp_processor_id() % h->nreply_queues; } } -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: hpsa - BUG: using smp_processor_id() in preemptible [00000000 00000000] code: kworker/u:0/6
- Original Message - > On Fri, Jul 26, 2013 at 06:28:02AM -0400, John Kacur wrote: > > > > > > - Original Message - > > > [Adding missing cc to linux-scsi] > > > On Thu, 2013-07-25 at 23:33 +0200, John Kacur wrote: > > > > Hi > > > > > > > > We're seeing this on a 3.6 kernel with the real-time patch applied, but > > > > it > > > > looks like it is relevant with the real-time patch in the latest kernel > > > > This should read, "it looks like it is relevant WITHOUT the real-time patch > > in the latest kernel". > > > > > > > > too. > > > > > > > > [ 49.688847] hpsa :03:00.0: hpsa0: <0x323a> at IRQ 67 using DAC > > > > [ 49.749928] scsi0 : hpsa > > > > [ 49.784437] BUG: using smp_processor_id() in preemptible [ > > > > ] code: kworker/u:0/6 > > > > [ 49.784465] caller is enqueue_cmd_and_start_io+0x5a/0x100 [hpsa] > > > > [ 49.784468] Pid: 6, comm: kworker/u:0 Not tainted > > > > 3.6.11.5-rt37.52.el6rt.x86_64.debug #1 > > > > [ 49.784471] Call Trace: > > > > [ 49.784512] [] debug_smp_processor_id+0x123/0x150 > > > > [ 49.784520] [] > > > > enqueue_cmd_and_start_io+0x5a/0x100 > > > > [hpsa] > > > > [ 49.784529] [] > > > > hpsa_scsi_do_simple_cmd_core+0xeb/0x110 [hpsa] > > > > [ 49.784537] [] ? > > > > swiotlb_dma_mapping_error+0x18/0x30 > > > > [ 49.784544] [] ? > > > > swiotlb_dma_mapping_error+0x18/0x30 > > > > [ 49.784553] [] > > > > hpsa_scsi_do_simple_cmd_with_retry+0x91/0x280 [hpsa] > > > > [ 49.784562] [] > > > > hpsa_scsi_do_report_luns.clone.2+0xd8/0x130 [hpsa] > > > > [ 49.784571] [] > > > > hpsa_gather_lun_info.clone.3+0x3a/0x1a0 [hpsa] > > > > [ 49.784580] [] > > > > hpsa_update_scsi_devices+0x11f/0x4f0 > > > > [hpsa] > > > > [ 49.784592] [] ? sub_preempt_count+0xa9/0xe0 > > > > [ 49.784601] [] hpsa_scan_start+0xfd/0x150 [hpsa] > > > > [ 49.784613] [] ? > > > > rt_spin_lock_slowunlock+0x78/0x90 > > > > [ 49.784626] [] do_scsi_scan_host+0x37/0xa0 > > > > [ 49.784632] [] do_scan_async+0x1a/0x30 > > > > [ 49.784643] [] async_run_entry_fn+0x9b/0x1d0 > > > > [ 49.784655] [] process_one_work+0x1f2/0x620 > > > > [ 49.784661] [] ? process_one_work+0x180/0x620 > > > > [ 49.784668] [] ? worker_thread+0x5e/0x3a0 > > > > [ 49.784674] [] ? async_schedule+0x20/0x20 > > > > [ 49.784681] [] worker_thread+0x133/0x3a0 > > > > [ 49.784688] [] ? manage_workers+0x190/0x190 > > > > [ 49.784696] [] kthread+0xa6/0xb0 > > > > [ 49.784707] [] kernel_thread_helper+0x4/0x10 > > > > [ 49.784715] [] ? finish_task_switch+0x8c/0x110 > > > > [ 49.784721] [] ? _raw_spin_unlock_irq+0x3b/0x70 > > > > [ 49.784727] [] ? retint_restore_args+0xe/0xe > > > > [ 49.784734] [] ? kthreadd+0x1e0/0x1e0 > > > > [ 49.784739] [] ? gs_change+0xb/0xb > > > > > > > > --- > > > > > > > > When I look at the code I see this call chain > > > > enqueue_cmd_and_start_io()-> > > > > set_performant_mode()-> > > > > smp_processor_id() > > > > Which if you have debugging enabled calls debug_processor_id() and > > > > triggers the warning. > > > > > > > > I'm not very familiar with the hpsa code, so I'm not entirely sure what > > > > the purpose of this line is > > > > > > > > c->Header.ReplyQueue = smp_processor_id() % h->nreply_queues; > > > > > > > > Is the purpose to simply try to get a range of ReplyQueue numbers, but > > > > somewhat arbitrary? Or is it necessary that the current processor_id > > > > is used? If it is the former, and you're not accessing per cpu > > > > structures, > > > > or pinning a cpu, or anything like that then I would think it is safe > > > > to > > > > change this to a raw_smp_processor_id() to get rid of a false positive > > > > warning. > > It's not critical that they match (will work if they don't) but for certain > workloads you can get more performance if you pin processes to cpus and > arrange msix
Re: hpsa - BUG: using smp_processor_id() in preemptible [00000000 00000000] code: kworker/u:0/6
- Original Message - > [Adding missing cc to linux-scsi] > On Thu, 2013-07-25 at 23:33 +0200, John Kacur wrote: > > Hi > > > > We're seeing this on a 3.6 kernel with the real-time patch applied, but it > > looks like it is relevant with the real-time patch in the latest kernel This should read, "it looks like it is relevant WITHOUT the real-time patch in the latest kernel". > > too. > > > > [ 49.688847] hpsa :03:00.0: hpsa0: <0x323a> at IRQ 67 using DAC > > [ 49.749928] scsi0 : hpsa > > [ 49.784437] BUG: using smp_processor_id() in preemptible [ > > ] code: kworker/u:0/6 > > [ 49.784465] caller is enqueue_cmd_and_start_io+0x5a/0x100 [hpsa] > > [ 49.784468] Pid: 6, comm: kworker/u:0 Not tainted > > 3.6.11.5-rt37.52.el6rt.x86_64.debug #1 > > [ 49.784471] Call Trace: > > [ 49.784512] [] debug_smp_processor_id+0x123/0x150 > > [ 49.784520] [] enqueue_cmd_and_start_io+0x5a/0x100 > > [hpsa] > > [ 49.784529] [] > > hpsa_scsi_do_simple_cmd_core+0xeb/0x110 [hpsa] > > [ 49.784537] [] ? swiotlb_dma_mapping_error+0x18/0x30 > > [ 49.784544] [] ? swiotlb_dma_mapping_error+0x18/0x30 > > [ 49.784553] [] > > hpsa_scsi_do_simple_cmd_with_retry+0x91/0x280 [hpsa] > > [ 49.784562] [] > > hpsa_scsi_do_report_luns.clone.2+0xd8/0x130 [hpsa] > > [ 49.784571] [] > > hpsa_gather_lun_info.clone.3+0x3a/0x1a0 [hpsa] > > [ 49.784580] [] hpsa_update_scsi_devices+0x11f/0x4f0 > > [hpsa] > > [ 49.784592] [] ? sub_preempt_count+0xa9/0xe0 > > [ 49.784601] [] hpsa_scan_start+0xfd/0x150 [hpsa] > > [ 49.784613] [] ? rt_spin_lock_slowunlock+0x78/0x90 > > [ 49.784626] [] do_scsi_scan_host+0x37/0xa0 > > [ 49.784632] [] do_scan_async+0x1a/0x30 > > [ 49.784643] [] async_run_entry_fn+0x9b/0x1d0 > > [ 49.784655] [] process_one_work+0x1f2/0x620 > > [ 49.784661] [] ? process_one_work+0x180/0x620 > > [ 49.784668] [] ? worker_thread+0x5e/0x3a0 > > [ 49.784674] [] ? async_schedule+0x20/0x20 > > [ 49.784681] [] worker_thread+0x133/0x3a0 > > [ 49.784688] [] ? manage_workers+0x190/0x190 > > [ 49.784696] [] kthread+0xa6/0xb0 > > [ 49.784707] [] kernel_thread_helper+0x4/0x10 > > [ 49.784715] [] ? finish_task_switch+0x8c/0x110 > > [ 49.784721] [] ? _raw_spin_unlock_irq+0x3b/0x70 > > [ 49.784727] [] ? retint_restore_args+0xe/0xe > > [ 49.784734] [] ? kthreadd+0x1e0/0x1e0 > > [ 49.784739] [] ? gs_change+0xb/0xb > > > > --- > > > > When I look at the code I see this call chain > > enqueue_cmd_and_start_io()-> > > set_performant_mode()-> > > smp_processor_id() > > Which if you have debugging enabled calls debug_processor_id() and > > triggers the warning. > > > > I'm not very familiar with the hpsa code, so I'm not entirely sure what > > the purpose of this line is > > > > c->Header.ReplyQueue = smp_processor_id() % h->nreply_queues; > > > > Is the purpose to simply try to get a range of ReplyQueue numbers, but > > somewhat arbitrary? Or is it necessary that the current processor_id > > is used? If it is the former, and you're not accessing per cpu structures, > > or pinning a cpu, or anything like that then I would think it is safe to > > change this to a raw_smp_processor_id() to get rid of a false positive > > warning. > > > > diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c > > index 7f4f790..4e19267 100644 > > --- a/drivers/scsi/hpsa.c > > +++ b/drivers/scsi/hpsa.c > > @@ -583,7 +583,7 @@ static void set_performant_mode(struct ctlr_info *h, > > struct CommandList *c) > > c->busaddr |= 1 | (h->blockFetchTable[c->Header.SGList] << 1); > > if (likely(h->msix_vector)) > > c->Header.ReplyQueue = > > - smp_processor_id() % h->nreply_queues; > > + raw_smp_processor_id() % h->nreply_queues; > > } > > } > > > > > > Thanks > > > > John Kacur > > > -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
