Commit 3a0aee48 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

x86/fpu: Rename math_state_restore() to fpu__restore() 



Move to the new fpu__*() namespace.

Reviewed-by: default avatarBorislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 93b90712

Documentation/preempt-locking.txt

+1 −1
Original line number Diff line number Diff line
@@ -48,7 +48,7 @@ preemption must be disabled around such regions. 


Note, some FPU functions are already explicitly preempt safe.  For example,

kernel_fpu_begin and kernel_fpu_end will disable and enable preemption.

However, math_state_restore must be called with preemption disabled.

However, fpu__restore() must be called with preemption disabled.





RULE #3: Lock acquire and release must be performed by same task

arch/x86/include/asm/i387.h

+1 −1
Original line number Diff line number Diff line
@@ -23,7 +23,7 @@ extern void fpstate_init(struct fpu *fpu); 
extern void fpu__flush_thread(struct task_struct *tsk);



extern int dump_fpu(struct pt_regs *, struct user_i387_struct *);

extern void math_state_restore(void);

extern void fpu__restore(void);



extern bool irq_fpu_usable(void);

arch/x86/kernel/fpu/core.c

+3 −3
Original line number Diff line number Diff line
@@ -228,7 +228,7 @@ static int fpu__unlazy_stopped(struct task_struct *child) 
}



/*

 * 'math_state_restore()' saves the current math information in the

 * 'fpu__restore()' saves the current math information in the

 * old math state array, and gets the new ones from the current task

 *

 * Careful.. There are problems with IBM-designed IRQ13 behaviour.
@@ -237,7 +237,7 @@ static int fpu__unlazy_stopped(struct task_struct *child) 
 * Must be called with kernel preemption disabled (eg with local

 * local interrupts as in the case of do_device_not_available).

 */

void math_state_restore(void)

void fpu__restore(void)

{

	struct task_struct *tsk = current;
@@ -267,7 +267,7 @@ void math_state_restore(void) 
	}

	kernel_fpu_enable();

}

EXPORT_SYMBOL_GPL(math_state_restore);

EXPORT_SYMBOL_GPL(fpu__restore);



void fpu__flush_thread(struct task_struct *tsk)

{

arch/x86/kernel/fpu/xsave.c

+1 −1
Original line number Diff line number Diff line
@@ -404,7 +404,7 @@ int __restore_xstate_sig(void __user *buf, void __user *buf_fx, int size) 
		set_used_math();

		if (use_eager_fpu()) {

			preempt_disable();

			math_state_restore();

			fpu__restore();

			preempt_enable();

		}

arch/x86/kernel/process_32.c

+1 −1
Original line number Diff line number Diff line
@@ -295,7 +295,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) 
	 * Leave lazy mode, flushing any hypercalls made here.

	 * This must be done before restoring TLS segments so

	 * the GDT and LDT are properly updated, and must be

	 * done before math_state_restore, so the TS bit is up

	 * done before fpu__restore(), so the TS bit is up

	 * to date.

	 */

	arch_end_context_switch(next_p);

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