From: Shivasharan S Date: Fri, 5 Jan 2018 13:27:45 +0000 (-0800) Subject: scsi: megaraid_sas: Selectively apply stream detection based on IO type X-Git-Tag: v4.1.12-124.31.3~1022 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=640bb47ff0d62caa829694f07e4ad155d4c656c7;p=users%2Fjedix%2Flinux-maple.git scsi: megaraid_sas: Selectively apply stream detection based on IO type Performance improvement: Current driver calls stream detection unconditionally for all IOs. Stream Detection logic is not required for most of the fast path IO. To improve performance, avoid stream detection logic and do it only if required. Below are the cases where stream detection is required in driver: 1. All non-FastPath IOs (IOs going to FW) 2. Fast Path reads sent to ReadAhead capable VDs. Signed-off-by: Sumit Saxena Signed-off-by: Shivasharan S Signed-off-by: Martin K. Petersen Orabug: 27625001 Signed-off-by: Jack Vogel Reviewed-by: Martin K. Petersen --- diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c index 603c9875cb7c..e64227f3d386 100644 --- a/drivers/scsi/megaraid/megaraid_sas_fusion.c +++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c @@ -2668,16 +2668,6 @@ megasas_build_ldio_fusion(struct megasas_instance *instance, praid_context = &io_request->RaidContext; if (instance->adapter_type == VENTURA_SERIES) { - spin_lock_irqsave(&instance->stream_lock, spinlock_flags); - megasas_stream_detect(instance, cmd, &io_info); - spin_unlock_irqrestore(&instance->stream_lock, spinlock_flags); - /* In ventura if stream detected for a read and it is read ahead - * capable make this IO as LDIO - */ - if (is_stream_detected(&io_request->RaidContext.raid_context_g35) && - io_info.isRead && io_info.ra_capable) - fp_possible = false; - /* FP for Optimal raid level 1. * All large RAID-1 writes (> 32 KiB, both WT and WB modes) * are built by the driver as LD I/Os. @@ -2703,6 +2693,20 @@ megasas_build_ldio_fusion(struct megasas_instance *instance, } } + if (!fp_possible || + (io_info.isRead && io_info.ra_capable)) { + spin_lock_irqsave(&instance->stream_lock, + spinlock_flags); + megasas_stream_detect(instance, cmd, &io_info); + spin_unlock_irqrestore(&instance->stream_lock, + spinlock_flags); + /* In ventura if stream detected for a read and it is + * read ahead capable make this IO as LDIO + */ + if (is_stream_detected(&io_request->RaidContext.raid_context_g35)) + fp_possible = false; + } + /* If raid is NULL, set CPU affinity to default CPU0 */ if (raid) megasas_set_raidflag_cpu_affinity(praid_context,