diff options
author | Kevin Hao <haokexin@gmail.com> | 2016-07-23 14:42:42 +0530 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2016-08-01 11:15:06 +1000 |
commit | c12e6f24d4137822d5019c1f78ac65bd27a3447d (patch) | |
tree | 7ebc50a5a62a36e89dc90e801da4f00e59633622 /arch/powerpc | |
parent | 4db7327194dba0cb91f274b0f606785a9ee5108d (diff) | |
download | linux-c12e6f24d4137822d5019c1f78ac65bd27a3447d.tar.bz2 |
powerpc: Add option to use jump label for mmu_has_feature()
As we just did for CPU features.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc')
-rw-r--r-- | arch/powerpc/include/asm/cpu_has_feature.h | 1 | ||||
-rw-r--r-- | arch/powerpc/include/asm/mmu.h | 38 | ||||
-rw-r--r-- | arch/powerpc/kernel/cputable.c | 17 | ||||
-rw-r--r-- | arch/powerpc/lib/feature-fixups.c | 1 |
4 files changed, 57 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/cpu_has_feature.h b/arch/powerpc/include/asm/cpu_has_feature.h index b9ce6425fdea..039c011b4252 100644 --- a/arch/powerpc/include/asm/cpu_has_feature.h +++ b/arch/powerpc/include/asm/cpu_has_feature.h @@ -3,6 +3,7 @@ #ifndef __ASSEMBLY__ +#include <linux/bug.h> #include <asm/cputable.h> static inline bool early_cpu_has_feature(unsigned long feature) diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h index 37f55169df3e..1bf919aafd50 100644 --- a/arch/powerpc/include/asm/mmu.h +++ b/arch/powerpc/include/asm/mmu.h @@ -141,6 +141,43 @@ static inline bool early_mmu_has_feature(unsigned long feature) return !!(MMU_FTRS_POSSIBLE & cur_cpu_spec->mmu_features & feature); } +#ifdef CONFIG_JUMP_LABEL_FEATURE_CHECKS +#include <linux/jump_label.h> + +#define NUM_MMU_FTR_KEYS 32 + +extern struct static_key_true mmu_feature_keys[NUM_MMU_FTR_KEYS]; + +extern void mmu_feature_keys_init(void); + +static __always_inline bool mmu_has_feature(unsigned long feature) +{ + int i; + + BUILD_BUG_ON(!__builtin_constant_p(feature)); + + if (!(MMU_FTRS_POSSIBLE & feature)) + return false; + + i = __builtin_ctzl(feature); + return static_branch_likely(&mmu_feature_keys[i]); +} + +static inline void mmu_clear_feature(unsigned long feature) +{ + int i; + + i = __builtin_ctzl(feature); + cur_cpu_spec->mmu_features &= ~feature; + static_branch_disable(&mmu_feature_keys[i]); +} +#else + +static inline void mmu_feature_keys_init(void) +{ + +} + static inline bool mmu_has_feature(unsigned long feature) { return early_mmu_has_feature(feature); @@ -150,6 +187,7 @@ static inline void mmu_clear_feature(unsigned long feature) { cur_cpu_spec->mmu_features &= ~feature; } +#endif /* CONFIG_JUMP_LABEL */ extern unsigned int __start___mmu_ftr_fixup, __stop___mmu_ftr_fixup; diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c index e3da41f8ef93..74248ab18e98 100644 --- a/arch/powerpc/kernel/cputable.c +++ b/arch/powerpc/kernel/cputable.c @@ -2243,4 +2243,21 @@ void __init cpu_feature_keys_init(void) static_branch_disable(&cpu_feature_keys[i]); } } + +struct static_key_true mmu_feature_keys[NUM_MMU_FTR_KEYS] = { + [0 ... NUM_MMU_FTR_KEYS - 1] = STATIC_KEY_TRUE_INIT +}; +EXPORT_SYMBOL_GPL(mmu_feature_keys); + +void __init mmu_feature_keys_init(void) +{ + int i; + + for (i = 0; i < NUM_MMU_FTR_KEYS; i++) { + unsigned long f = 1ul << i; + + if (!(cur_cpu_spec->mmu_features & f)) + static_branch_disable(&mmu_feature_keys[i]); + } +} #endif diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c index 7a6ccbb74d91..077fa0ce3382 100644 --- a/arch/powerpc/lib/feature-fixups.c +++ b/arch/powerpc/lib/feature-fixups.c @@ -196,6 +196,7 @@ void __init apply_feature_fixups(void) */ jump_label_init(); cpu_feature_keys_init(); + mmu_feature_keys_init(); } static int __init check_features(void) |