From: Anton Blanchard <anton@samba.org>
To: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au,
mikey@neuling.org, cyrilbur@gmail.com
Cc: linuxppc-dev@lists.ozlabs.org
Subject: [PATCH 12/19] powerpc: Create msr_check_and_{set,clear}()
Date: Wed, 28 Oct 2015 11:51:00 +1100 [thread overview]
Message-ID: <1445993467-667-12-git-send-email-anton@samba.org> (raw)
In-Reply-To: <1445993467-667-1-git-send-email-anton@samba.org>
Create helper functions to set and clear MSR bits after first
checking if they are already set. Grouping them will make it
easy to avoid the MSR writes in a subsequent optimisation.
Signed-off-by: Anton Blanchard <anton@samba.org>
---
arch/powerpc/kernel/process.c | 107 ++++++++++++++++++++----------------------
1 file changed, 52 insertions(+), 55 deletions(-)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index c39aa5a..5f244d0 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -87,23 +87,46 @@ static void check_if_tm_restore_required(struct task_struct *tsk)
static inline void check_if_tm_restore_required(struct task_struct *tsk) { }
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
-#ifdef CONFIG_PPC_FPU
-void giveup_fpu(struct task_struct *tsk)
+static void msr_check_and_set(unsigned long bits)
{
- u64 oldmsr = mfmsr();
- u64 newmsr;
+ unsigned long oldmsr = mfmsr();
+ unsigned long newmsr;
- check_if_tm_restore_required(tsk);
+ newmsr = oldmsr | bits;
- newmsr = oldmsr | MSR_FP;
#ifdef CONFIG_VSX
- if (cpu_has_feature(CPU_FTR_VSX))
+ if (cpu_has_feature(CPU_FTR_VSX) && (bits & MSR_FP))
newmsr |= MSR_VSX;
#endif
+
if (oldmsr != newmsr)
mtmsr_isync(newmsr);
+}
+
+static void msr_check_and_clear(unsigned long bits)
+{
+ unsigned long oldmsr = mfmsr();
+ unsigned long newmsr;
+
+ newmsr = oldmsr & ~bits;
+
+#ifdef CONFIG_VSX
+ if (cpu_has_feature(CPU_FTR_VSX) && (bits & MSR_FP))
+ newmsr &= ~MSR_VSX;
+#endif
+ if (oldmsr != newmsr)
+ mtmsr_isync(newmsr);
+}
+
+#ifdef CONFIG_PPC_FPU
+void giveup_fpu(struct task_struct *tsk)
+{
+ check_if_tm_restore_required(tsk);
+
+ msr_check_and_set(MSR_FP);
__giveup_fpu(tsk);
+ msr_check_and_clear(MSR_FP);
}
EXPORT_SYMBOL(giveup_fpu);
@@ -144,30 +167,21 @@ void enable_kernel_fp(void)
{
WARN_ON(preemptible());
- if (current->thread.regs && (current->thread.regs->msr & MSR_FP)) {
- giveup_fpu(current);
- } else {
- u64 oldmsr = mfmsr();
+ msr_check_and_set(MSR_FP);
- if (!(oldmsr & MSR_FP))
- mtmsr_isync(oldmsr | MSR_FP);
- }
+ if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
+ __giveup_fpu(current);
}
EXPORT_SYMBOL(enable_kernel_fp);
#ifdef CONFIG_ALTIVEC
void giveup_altivec(struct task_struct *tsk)
{
- u64 oldmsr = mfmsr();
- u64 newmsr;
-
check_if_tm_restore_required(tsk);
- newmsr = oldmsr | MSR_VEC;
- if (oldmsr != newmsr)
- mtmsr_isync(newmsr);
-
+ msr_check_and_set(MSR_VEC);
__giveup_altivec(tsk);
+ msr_check_and_clear(MSR_VEC);
}
EXPORT_SYMBOL(giveup_altivec);
@@ -175,14 +189,10 @@ void enable_kernel_altivec(void)
{
WARN_ON(preemptible());
- if (current->thread.regs && (current->thread.regs->msr & MSR_VEC)) {
- giveup_altivec(current);
- } else {
- u64 oldmsr = mfmsr();
+ msr_check_and_set(MSR_VEC);
- if (!(oldmsr & MSR_VEC))
- mtmsr_isync(oldmsr | MSR_VEC);
- }
+ if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
+ __giveup_altivec(current);
}
EXPORT_SYMBOL(enable_kernel_altivec);
@@ -207,20 +217,15 @@ EXPORT_SYMBOL_GPL(flush_altivec_to_thread);
#ifdef CONFIG_VSX
void giveup_vsx(struct task_struct *tsk)
{
- u64 oldmsr = mfmsr();
- u64 newmsr;
-
check_if_tm_restore_required(tsk);
- newmsr = oldmsr | (MSR_FP|MSR_VEC|MSR_VSX);
- if (oldmsr != newmsr)
- mtmsr_isync(newmsr);
-
+ msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX);
if (tsk->thread.regs->msr & MSR_FP)
__giveup_fpu(tsk);
if (tsk->thread.regs->msr & MSR_VEC)
__giveup_altivec(tsk);
__giveup_vsx(tsk);
+ msr_check_and_clear(MSR_FP|MSR_VEC|MSR_VSX);
}
EXPORT_SYMBOL(giveup_vsx);
@@ -228,13 +233,14 @@ void enable_kernel_vsx(void)
{
WARN_ON(preemptible());
- if (current->thread.regs && (current->thread.regs->msr & MSR_VSX)) {
- giveup_vsx(current);
- } else {
- u64 oldmsr = mfmsr();
+ msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX);
- if (!(oldmsr & MSR_VSX))
- mtmsr_isync(oldmsr | MSR_VSX);
+ if (current->thread.regs && (current->thread.regs->msr & MSR_VSX)) {
+ if (current->thread.regs->msr & MSR_FP)
+ __giveup_fpu(current);
+ if (current->thread.regs->msr & MSR_VEC)
+ __giveup_altivec(current);
+ __giveup_vsx(current);
}
}
EXPORT_SYMBOL(enable_kernel_vsx);
@@ -256,16 +262,11 @@ EXPORT_SYMBOL_GPL(flush_vsx_to_thread);
#ifdef CONFIG_SPE
void giveup_spe(struct task_struct *)
{
- u64 oldmsr = mfmsr();
- u64 newmsr;
-
check_if_tm_restore_required(tsk);
- newmsr = oldmsr | MSR_SPE;
- if (oldmsr != newmsr)
- mtmsr_isync(newmsr);
-
+ msr_check_and_set(MSR_SPE);
__giveup_spe(tsk);
+ msr_check_and_clear(MSR_SPE);
}
EXPORT_SYMBOL(giveup_spe);
@@ -273,14 +274,10 @@ void enable_kernel_spe(void)
{
WARN_ON(preemptible());
- if (current->thread.regs && (current->thread.regs->msr & MSR_SPE)) {
- giveup_spe(current);
- } else {
- u64 oldmsr = mfmsr();
+ msr_check_and_set(MSR_SPE);
- if (!(oldmsr & MSR_SPE))
- mtmsr_isync(oldmsr | MSR_SPE);
- }
+ if (current->thread.regs && (current->thread.regs->msr & MSR_SPE))
+ __giveup_spe(current);
}
EXPORT_SYMBOL(enable_kernel_spe);
--
2.5.0
next prev parent reply other threads:[~2015-10-28 0:51 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-28 0:50 [PATCH 01/19] powerpc: Don't disable kernel FP/VMX/VSX MSR bits on context switch Anton Blanchard
2015-10-28 0:50 ` [PATCH 02/19] powerpc: Don't disable MSR bits in do_load_up_transact_*() functions Anton Blanchard
2015-10-28 0:50 ` [PATCH 03/19] powerpc: Create context switch helpers save_sprs() and restore_sprs() Anton Blanchard
2015-10-28 0:50 ` [PATCH 04/19] powerpc: Remove redundant mflr in _switch Anton Blanchard
2015-10-28 0:50 ` [PATCH 05/19] powerpc: Remove UP only lazy floating point and vector optimisations Anton Blanchard
2015-10-28 0:50 ` [PATCH 06/19] powerpc: Simplify TM restore checks Anton Blanchard
2015-10-28 0:50 ` [PATCH 07/19] powerpc: Create mtmsrd_isync() Anton Blanchard
2015-10-28 0:50 ` [PATCH 08/19] powerpc: Remove NULL task struct pointer checks in FP and vector code Anton Blanchard
2015-10-28 0:50 ` [PATCH 09/19] powerpc: Move part of giveup_fpu,altivec,spe into c Anton Blanchard
2015-10-28 3:17 ` [PATCH 09/19] powerpc: Move part of giveup_fpu, altivec, spe " kbuild test robot
2015-10-28 0:50 ` [PATCH 10/19] powerpc: Move part of giveup_vsx " Anton Blanchard
2015-10-28 0:50 ` [PATCH 11/19] crypto: vmx: Only call enable_kernel_vsx() Anton Blanchard
2015-10-28 0:51 ` Anton Blanchard [this message]
2015-10-28 0:51 ` [PATCH 13/19] powerpc: Create disable_kernel_{fp,altivec,vsx,spe}() Anton Blanchard
2015-10-28 0:51 ` [PATCH 14/19] powerpc: Add ppc_strict_facility_enable boot option Anton Blanchard
2015-10-28 0:51 ` [PATCH 15/19] powerpc: Remove fp_enable() and vec_enable(), use msr_check_and_{set, clear}() Anton Blanchard
2015-10-28 0:51 ` [PATCH 16/19] powerpc: create giveup_all() Anton Blanchard
2015-10-28 0:51 ` [PATCH 17/19] powerpc: create flush_all_to_thread() Anton Blanchard
2015-10-28 0:51 ` [PATCH 18/19] powerpc: Rearrange __switch_to() Anton Blanchard
2015-10-28 0:51 ` [PATCH 19/19] powerpc: clean up asm/switch_to.h Anton Blanchard
2015-10-28 3:19 ` kbuild test robot
2015-10-28 4:24 ` kbuild test robot
-- strict thread matches above, loose matches on Subject: below --
2015-10-29 0:43 [PATCH 00/19] Context switch improvements Anton Blanchard
2015-10-29 0:44 ` [PATCH 12/19] powerpc: Create msr_check_and_{set,clear}() Anton Blanchard
2015-10-29 7:25 ` kbuild test robot
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