Commit 685c930d authored by Ingo Molnar's avatar Ingo Molnar
Browse files

x86/fpu: Remove fpu__current_fpstate_write_begin/end() 

These functions are not used anymore, so remove them.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-29-mingo@kernel.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 4618e909

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

+0 −2
Original line number Diff line number Diff line
@@ -26,8 +26,6 @@ 
extern void fpu__activate_curr(struct fpu *fpu);

extern void fpu__activate_fpstate_read(struct fpu *fpu);

extern void fpu__activate_fpstate_write(struct fpu *fpu);

extern void fpu__current_fpstate_write_begin(void);

extern void fpu__current_fpstate_write_end(void);

extern void fpu__save(struct fpu *fpu);

extern void fpu__restore(struct fpu *fpu);

extern int  fpu__restore_sig(void __user *buf, int ia32_frame);

arch/x86/kernel/fpu/core.c

+0 −63
Original line number Diff line number Diff line
@@ -316,69 +316,6 @@ void fpu__activate_fpstate_write(struct fpu *fpu) 
	}

}



/*

 * This function must be called before we write the current

 * task's fpstate.

 *

 * This call gets the current FPU register state and moves

 * it in to the 'fpstate'.  Preemption is disabled so that

 * no writes to the 'fpstate' can occur from context

 * swiches.

 *

 * Must be followed by a fpu__current_fpstate_write_end().

 */

void fpu__current_fpstate_write_begin(void)

{

	struct fpu *fpu = &current->thread.fpu;



	/*

	 * Ensure that the context-switching code does not write

	 * over the fpstate while we are doing our update.

	 */

	preempt_disable();



	/*

	 * Move the fpregs in to the fpu's 'fpstate'.

	 */

	fpu__activate_fpstate_read(fpu);



	/*

	 * The caller is about to write to 'fpu'.  Ensure that no

	 * CPU thinks that its fpregs match the fpstate.  This

	 * ensures we will not be lazy and skip a XRSTOR in the

	 * future.

	 */

	__fpu_invalidate_fpregs_state(fpu);

}



/*

 * This function must be paired with fpu__current_fpstate_write_begin()

 *

 * This will ensure that the modified fpstate gets placed back in

 * the fpregs if necessary.

 *

 * Note: This function may be called whether or not an _actual_

 * write to the fpstate occurred.

 */

void fpu__current_fpstate_write_end(void)

{

	struct fpu *fpu = &current->thread.fpu;



	/*

	 * 'fpu' now has an updated copy of the state, but the

	 * registers may still be out of date.  Update them with

	 * an XRSTOR if they are active.

	 */

	if (fpu->fpstate_active)

		copy_kernel_to_fpregs(&fpu->state);



	/*

	 * Our update is done and the fpregs/fpstate are in sync

	 * if necessary.  Context switches can happen again.

	 */

	preempt_enable();

}



/*

 * 'fpu__restore()' is called to copy FPU registers from

 * the FPU fpstate to the live hw registers and to activate

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