From: Oleg Drokin <oleg.drokin@intel.com>
Date: Fri, 27 Feb 2015 07:59:05 +0000 (-0500)
Subject: LU-6285 ptlrpc: Do not recalculate siblings of CPU 0 in a loop
X-Git-Tag: 2.7.52~18
X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=commitdiff_plain;h=0eb4582d87e32dd3e5491e13ba659e625624bfe7;hp=b4f41e5fef3ff644f9adb95921329ef59e1e3e74

LU-6285 ptlrpc: Do not recalculate siblings of CPU 0 in a loop

ptlrpc_hr_init seems to be recalculating number of siblings of CPU0
in a loop which is wasteful. Just precalculate the value before the
loop and use it in every iteration instead.

Change-Id: I807fddf29a75af4d268829e37dc91b7512cfcc50
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Reviewed-on: http://review.whamcloud.com/13905
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Liang Zhen <liang.zhen@intel.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
---

diff --git a/lustre/ptlrpc/service.c b/lustre/ptlrpc/service.c
index 267685c..586b1e9 100644
--- a/lustre/ptlrpc/service.c
+++ b/lustre/ptlrpc/service.c
@@ -2896,6 +2896,7 @@ int ptlrpc_hr_init(void)
 	int				rc;
 	int				i;
 	int				j;
+	int				weight;
 	ENTRY;
 
 	memset(&ptlrpc_hr, 0, sizeof(ptlrpc_hr));
@@ -2908,6 +2909,8 @@ int ptlrpc_hr_init(void)
 
 	init_waitqueue_head(&ptlrpc_hr.hr_waitq);
 
+	weight = cfs_cpu_ht_nsiblings(0);
+
 	cfs_percpt_for_each(hrp, i, ptlrpc_hr.hr_partitions) {
 		hrp->hrp_cpt = i;
 
@@ -2915,7 +2918,7 @@ int ptlrpc_hr_init(void)
 		atomic_set(&hrp->hrp_nstopped, 0);
 
 		hrp->hrp_nthrs = cfs_cpt_weight(ptlrpc_hr.hr_cpt_table, i);
-		hrp->hrp_nthrs /= cfs_cpu_ht_nsiblings(0);
+		hrp->hrp_nthrs /= weight;
 
 		LASSERT(hrp->hrp_nthrs > 0);
 		OBD_CPT_ALLOC(hrp->hrp_thrs, ptlrpc_hr.hr_cpt_table, i,