diff options
| author | Sumit Singh <sumsingh@nvidia.com> | 2014-04-21 11:09:58 +0530 |
|---|---|---|
| committer | Mandar Padmawar <mpadmawar@nvidia.com> | 2014-06-24 04:48:06 -0700 |
| commit | c59d2989479d6431f4e83e2829c6cf25fc3f1184 (patch) | |
| tree | 799b81e91b2a3a15e3164a408ff99e8c340b17a4 /kernel | |
| parent | 0d1081f5f2a34f082deac2590835cd7bf15bedef (diff) | |
smp: enhance power efficiency
Here we are trying to reduce power usage through the
use of macros cpu_relaxed_read_short and cpu_relaxed_read.
Bug 1440421
Change-Id: I114d122cf58b1cf7b93b4b5f5d712360a2f1e096
Signed-off-by: Sumit Singh <sumsingh@nvidia.com>
Reviewed-on: http://git-master/r/425947
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Sri Krishna Chowdary <schowdary@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Alexander Van Brunt <avanbrunt@nvidia.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/smp.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/smp.c b/kernel/smp.c index 5221ac677e60..1acf2bd32dbe 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -2,6 +2,7 @@ * Generic helpers for smp ipi calls * * (C) Jens Axboe <jens.axboe@oracle.com> 2008 + * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved. */ #include <linux/rcupdate.h> #include <linux/rculist.h> @@ -12,6 +13,7 @@ #include <linux/gfp.h> #include <linux/smp.h> #include <linux/cpu.h> +#include <asm/relaxed.h> #include "smpboot.h" @@ -101,8 +103,8 @@ void __init call_function_init(void) */ static void csd_lock_wait(struct call_single_data *csd) { - while (csd->flags & CSD_FLAG_LOCK) - cpu_relax(); + while (cpu_relaxed_read_short(&csd->flags) & CSD_FLAG_LOCK) + cpu_read_relax(); } static void csd_lock(struct call_single_data *csd) |