x86/fpu: Simplify fpregs_[un]lock() (5f0c7127) · Commits · 戴 / test

There is no point in disabling preemption and then disabling bottom halfs. Just disabling bottom halfs is sufficient as it implicitly disables preemption on !RT kernels. Signed-off-by:

Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201027101349.455380473@linutronix.de

arch/x86/include/asm/fpu/api.h

+3 −2

Original line number	Diff line number	Diff line
		@@ -29,17 +29,18 @@ extern void fpregs_mark_activate(void);
		* A context switch will (and softirq might) save CPU's FPU registers to
		* fpu->state and set TIF_NEED_FPU_LOAD leaving CPU's FPU registers in
		* a random state.
		*
		* local_bh_disable() protects against both preemption and soft interrupts
		* on !RT kernels.
		*/
		static inline void fpregs_lock(void)
		{
		preempt_disable();
		local_bh_disable();
		}

		static inline void fpregs_unlock(void)
		{
		local_bh_enable();
		preempt_enable();
		}

		#ifdef CONFIG_X86_DEBUG_FPU

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