From 7654fa770bf7a3755ce349fbf3552cf026c35af3 Mon Sep 17 00:00:00 2001 From: Sumit Singh Date: Wed, 12 Mar 2014 14:44:44 +0530 Subject: thread_info: enhance power efficiency Using cpu_relaxed_read_long and defining relaxed version of some macros, and functions so that it can be used to improve power efficiency. bug 1440421 Change-Id: If857ff7110cffadc6f13289a6395d253a8e3e232 Signed-off-by: Sumit Singh Reviewed-on: http://git-master/r/380859 (cherry picked from commit a66b23c6971403594cc6a82923c8df3b8472de90) Reviewed-on: http://git-master/r/422251 Reviewed-by: Automatic_Commit_Validation_User GVS: Gerrit_Virtual_Submit Reviewed-by: Bharat Nihalani Signed-off-by: franciscofranco --- include/linux/thread_info.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include') diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h index 4ae6f32c8..c7e3e8ff7 100644 --- a/include/linux/thread_info.h +++ b/include/linux/thread_info.h @@ -2,6 +2,8 @@ * * Copyright (C) 2002 David Howells (dhowells@redhat.com) * - Incorporating suggestions made by Linus Torvalds + * + * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved. */ #ifndef _LINUX_THREAD_INFO_H @@ -9,6 +11,7 @@ #include #include +#include struct timespec; struct compat_timespec; @@ -88,6 +91,12 @@ static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag return test_and_clear_bit(flag, (unsigned long *)&ti->flags); } +static inline int test_ti_thread_flag_relaxed(struct thread_info *ti, int flag) +{ + ti->flags = cpu_relaxed_read_long(&ti->flags); + return test_bit(flag, (unsigned long *)&ti->flags); +} + static inline int test_ti_thread_flag(struct thread_info *ti, int flag) { return test_bit(flag, (unsigned long *)&ti->flags); @@ -103,12 +112,16 @@ static inline int test_ti_thread_flag(struct thread_info *ti, int flag) test_and_clear_ti_thread_flag(current_thread_info(), flag) #define test_thread_flag(flag) \ test_ti_thread_flag(current_thread_info(), flag) +#define test_thread_flag_relaxed(flag) \ + test_ti_thread_flag_relaxed(current_thread_info(), flag) #define set_need_resched() set_thread_flag(TIF_NEED_RESCHED) #define clear_need_resched() clear_thread_flag(TIF_NEED_RESCHED) #define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED) +#define tif_need_resched_relaxed() test_thread_flag_relaxed(TIF_NEED_RESCHED) + #if defined TIF_RESTORE_SIGMASK && !defined HAVE_SET_RESTORE_SIGMASK /* * An arch can define its own version of set_restore_sigmask() to get the -- cgit v1.2.3