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authorShivasharan S <shivasharan.srikanteshwara@broadcom.com>2018-01-05 05:27:45 -0800
committerMartin K. Petersen <martin.petersen@oracle.com>2018-01-10 23:25:18 -0500
commit4959e61b83a3bc53d49b023dcb4dc50150c2795e (patch)
tree2fb2a606ba65ec9d0c62e20e5ba88e7661bf088b
parent5f19f7c879c4aacdb54d02a79e19d97064c9c999 (diff)
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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 <sumit.saxena@broadcom.com> Signed-off-by: Shivasharan S <shivasharan.srikanteshwara@broadcom.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
-rw-r--r--drivers/scsi/megaraid/megaraid_sas_fusion.c24
1 files changed, 14 insertions, 10 deletions
diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c
index 74dadd052be4..ef36f2ac7cb6 100644
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -2664,16 +2664,6 @@ 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.
@@ -2699,6 +2689,20 @@ 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,