On Wed, 2014-01-08 at 12:16 +0000, Saxena, Sumit wrote: > > >-----Original Message----- > >From: Wei Yongjun [mailto:weiyj.lk@xxxxxxxxx] > >Sent: Friday, December 20, 2013 8:38 AM > >To: DL-MegaRAID Linux; JBottomley@xxxxxxxxxxxxx; simon.puels@xxxxxxxxx; > >jkosina@xxxxxxx > >Cc: yongjun_wei@xxxxxxxxxxxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx > >Subject: [PATCH] [SCSI] megaraid: use GFP_ATOMIC under spin lock > > > >From: Wei Yongjun <yongjun_wei@xxxxxxxxxxxxxxxxx> > > > >A spin lock is taken here so we should use GFP_ATOMIC. > > > >Signed-off-by: Wei Yongjun <yongjun_wei@xxxxxxxxxxxxxxxxx> > >--- > > drivers/scsi/megaraid/megaraid_mm.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > >diff --git a/drivers/scsi/megaraid/megaraid_mm.c > >b/drivers/scsi/megaraid/megaraid_mm.c > >index a706927..99fa5d3 100644 > >--- a/drivers/scsi/megaraid/megaraid_mm.c > >+++ b/drivers/scsi/megaraid/megaraid_mm.c > >@@ -570,7 +570,7 @@ mraid_mm_attach_buf(mraid_mmadp_t *adp, uioc_t > >*kioc, int xferlen) > > > > kioc->pool_index = right_pool; > > kioc->free_buf = 1; > >- kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_KERNEL, > >+ kioc->buf_vaddr = pci_pool_alloc(pool->handle, > >GFP_ATOMIC, > > &kioc->buf_paddr); > > spin_unlock_irqrestore(&pool->lock, flags); > > > > > Acked-by: Sumit Saxena <sumit.saxena@xxxxxxx> This doesn't look like the right fix to me. What is the function of pool->lock around this code region? The only data you use from the pool is pool->handle which is set up at init time ... there's no need to use a lock to read a piece of data which is effectively constant, so just drop the lock. James -- 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
