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| author | Catalin Marinas | 2016-09-05 19:25:48 +0200 |
|---|---|---|
| committer | Will Deacon | 2016-09-07 10:41:42 +0200 |
| commit | efd9e03facd075f5b76bf82e6c785bd45d5cbf4f (patch) | |
| tree | f271f509acaba940a50d978a14713585f34b8667 /arch/arm64/kernel/cpufeature.c | |
| parent | jump_labels: Allow array initialisers (diff) | |
| download | kernel-qcow2-linux-efd9e03facd075f5b76bf82e6c785bd45d5cbf4f.tar.gz kernel-qcow2-linux-efd9e03facd075f5b76bf82e6c785bd45d5cbf4f.tar.xz kernel-qcow2-linux-efd9e03facd075f5b76bf82e6c785bd45d5cbf4f.zip | |
arm64: Use static keys for CPU features
This patch adds static keys transparently for all the cpu_hwcaps
features by implementing an array of default-false static keys and
enabling them when detected. The cpus_have_cap() check uses the static
keys if the feature being checked is a constant, otherwise the compiler
generates the bitmap test.
Because of the early call to static_branch_enable() via
check_local_cpu_errata() -> update_cpu_capabilities(), the jump labels
are initialised in cpuinfo_store_boot_cpu().
Cc: Will Deacon <will.deacon@arm.com>
Cc: Suzuki K. Poulose <Suzuki.Poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/kernel/cpufeature.c')
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index c3d7ae48f92d..9128ced913e7 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -46,6 +46,9 @@ unsigned int compat_elf_hwcap2 __read_mostly; DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS); +DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS); +EXPORT_SYMBOL(cpu_hwcap_keys); + #define __ARM64_FTR_BITS(SIGNED, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \ { \ .sign = SIGNED, \ |