From: Cyril Bur <cyrilbur@gmail.com>
To: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH v5 04/20] powerpc: Return the new MSR from msr_check_and_set()
Date: Fri, 23 Sep 2016 16:18:10 +1000 [thread overview]
Message-ID: <20160923061826.30790-5-cyrilbur@gmail.com> (raw)
In-Reply-To: <20160923061826.30790-1-cyrilbur@gmail.com>
msr_check_and_set() always performs a mfmsr() to determine if it needs
to perform an mtmsr(), as mfmsr() can be a costly operation
msr_check_and_set() could return the MSR now on the CPU to avoid
callers of msr_check_and_set having to make their own mfmsr() call.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
---
arch/powerpc/include/asm/reg.h | 2 +-
arch/powerpc/kernel/process.c | 4 +++-
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 9dddabc..a8f63bc 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -1250,7 +1250,7 @@ static inline void mtmsr_isync(unsigned long val)
: "memory")
#endif
-extern void msr_check_and_set(unsigned long bits);
+extern unsigned long msr_check_and_set(unsigned long bits);
extern bool strict_msr_control;
extern void __msr_check_and_clear(unsigned long bits);
static inline void msr_check_and_clear(unsigned long bits)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 5029567..34ee5f2 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -111,7 +111,7 @@ static int __init enable_strict_msr_control(char *str)
}
early_param("ppc_strict_facility_enable", enable_strict_msr_control);
-void msr_check_and_set(unsigned long bits)
+unsigned long msr_check_and_set(unsigned long bits)
{
unsigned long oldmsr = mfmsr();
unsigned long newmsr;
@@ -125,6 +125,8 @@ void msr_check_and_set(unsigned long bits)
if (oldmsr != newmsr)
mtmsr_isync(newmsr);
+
+ return newmsr;
}
void __msr_check_and_clear(unsigned long bits)
--
2.10.0
next prev parent reply other threads:[~2016-09-23 6:18 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-23 6:18 [PATCH v5 00/20] Consistent TM structures Cyril Bur
2016-09-23 6:18 ` [PATCH v5 01/20] selftests/powerpc: Compile selftests against headers without AT_HWCAP2 Cyril Bur
2016-09-28 11:34 ` [v5, " Michael Ellerman
2016-09-23 6:18 ` [PATCH v5 02/20] powerpc: Always restore FPU/VEC/VSX if hardware transactional memory in use Cyril Bur
2016-10-05 2:36 ` [v5, " Michael Ellerman
2016-09-23 6:18 ` [PATCH v5 03/20] powerpc: Add check_if_tm_restore_required() to giveup_all() Cyril Bur
2016-09-23 6:18 ` Cyril Bur [this message]
2016-09-23 6:18 ` [PATCH v5 05/20] powerpc: Never giveup a reclaimed thread when enabling kernel {fp, altivec, vsx} Cyril Bur
2016-09-23 6:18 ` [PATCH v5 06/20] powerpc: signals: Stop using current in signal code Cyril Bur
2016-09-23 6:18 ` [PATCH v5 07/20] selftests/powerpc: Check for VSX preservation across userspace preemption Cyril Bur
2016-09-23 6:18 ` [PATCH v5 08/20] selftests/powerpc: Rework FPU stack placement macros and move to header file Cyril Bur
2016-09-23 6:18 ` [PATCH v5 09/20] selftests/powerpc: Move VMX stack frame macros " Cyril Bur
2016-09-23 6:18 ` [PATCH v5 10/20] selftests/powerpc: Introduce GPR asm helper " Cyril Bur
2016-09-23 6:18 ` [PATCH v5 11/20] selftests/powerpc: Allow tests to extend their kill timeout Cyril Bur
2016-09-23 6:18 ` [PATCH v5 12/20] selftests/powerpc: Add TM tcheck helpers in C Cyril Bur
2016-09-23 6:18 ` [PATCH v5 13/20] selftests/powerpc: Check that signals always get delivered Cyril Bur
2016-09-23 6:18 ` [PATCH v5 14/20] selftests/powerpc: Add checks for transactional GPRs in signal contexts Cyril Bur
2016-09-23 6:18 ` [PATCH v5 15/20] selftests/powerpc: Add checks for transactional FPUs " Cyril Bur
2016-09-23 6:18 ` [PATCH v5 16/20] selftests/powerpc: Add checks for transactional VMXs " Cyril Bur
2016-09-23 6:18 ` [PATCH v5 17/20] selftests/powerpc: Add checks for transactional VSXs " Cyril Bur
2016-09-23 6:18 ` [PATCH v5 18/20] powerpc: tm: Always use fp_state and vr_state to store live registers Cyril Bur
2016-09-23 6:18 ` [PATCH v5 19/20] powerpc: tm: Rename transct_(*) to ck(\1)_state Cyril Bur
2016-09-23 6:18 ` [PATCH v5 20/20] powerpc: Remove do_load_up_transact_{fpu,altivec} Cyril Bur
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