Commit-ID: 631fe154edb0a37308d0116a0f9b7bba9dca6218 Gitweb: https://git.kernel.org/tip/631fe154edb0a37308d0116a0f9b7bba9dca6218 Author: Davidlohr Bueso <d...@stgolabs.net> AuthorDate: Mon, 26 Mar 2018 14:09:27 -0700 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Tue, 27 Mar 2018 07:53:00 +0200
perf/x86: Update rdpmc_always_available static key to the modern API No changes in refcount semantics -- use DEFINE_STATIC_KEY_FALSE() for initialization and replace: static_key_slow_inc|dec() => static_branch_inc|dec() static_key_false() => static_branch_unlikely() Added a '_key' suffix to rdpmc_always_available, for better self-documentation. Signed-off-by: Davidlohr Bueso <dbu...@suse.de> Cc: Davidlohr Bueso <d...@stgolabs.net> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: a...@linux-foundation.org Link: http://lkml.kernel.org/r/20180326210929.5244-5-d...@stgolabs.net Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/events/core.c | 6 +++--- arch/x86/include/asm/mmu_context.h | 5 +++-- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 4823695c459f..a6006e7bb729 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -48,7 +48,7 @@ DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = { .enabled = 1, }; -struct static_key rdpmc_always_available = STATIC_KEY_INIT_FALSE; +DEFINE_STATIC_KEY_FALSE(rdpmc_always_available_key); u64 __read_mostly hw_cache_event_ids [PERF_COUNT_HW_CACHE_MAX] @@ -2206,9 +2206,9 @@ static ssize_t set_attr_rdpmc(struct device *cdev, * but only root can trigger it, so it's okay. */ if (val == 2) - static_key_slow_inc(&rdpmc_always_available); + static_branch_inc(&rdpmc_always_available_key); else - static_key_slow_dec(&rdpmc_always_available); + static_branch_dec(&rdpmc_always_available_key); on_each_cpu(refresh_pce, NULL, 1); } diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 1de72ce514cd..57e3785d0d26 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -24,11 +24,12 @@ static inline void paravirt_activate_mm(struct mm_struct *prev, #endif /* !CONFIG_PARAVIRT */ #ifdef CONFIG_PERF_EVENTS -extern struct static_key rdpmc_always_available; + +DECLARE_STATIC_KEY_FALSE(rdpmc_always_available_key); static inline void load_mm_cr4(struct mm_struct *mm) { - if (static_key_false(&rdpmc_always_available) || + if (static_branch_unlikely(&rdpmc_always_available_key) || atomic_read(&mm->context.perf_rdpmc_allowed)) cr4_set_bits(X86_CR4_PCE); else
