Commit bfc2eae0 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/vdso32: miscellaneous optimisations 



Various optimisations by inverting branches and removing
redundant instructions.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b4e79f963845545bcce1459cd6fcfe46bdde7863.1575273217.git.christophe.leroy@c-s.fr
parent e33ffc95

arch/powerpc/kernel/vdso32/datapage.S

+1 −2
Original line number Diff line number Diff line
@@ -30,11 +30,10 @@ V_FUNCTION_BEGIN(__kernel_get_syscall_map) 
  .cfi_startproc

	mflr	r12

  .cfi_register lr,r12

	mr	r4,r3

	mr.	r4,r3

	get_datapage	r3, r0

	mtlr	r12

	addi	r3,r3,CFG_SYSCALL_MAP32

	cmpli	cr0,r4,0

	beqlr

	li	r0,NR_syscalls

	stw	r0,0(r4)

arch/powerpc/kernel/vdso32/getcpu.S

+3 −3
Original line number Diff line number Diff line
@@ -25,10 +25,10 @@ V_FUNCTION_BEGIN(__kernel_getcpu) 
	rlwinm  r7,r5,16,31-15,31-0

	beq	cr0,1f

	stw	r6,0(r3)

1:	beq	cr1,2f

	stw	r7,0(r4)

2:	crclr	cr0*4+so

1:	crclr	cr0*4+so

	li	r3,0			/* always success */

	beqlr	cr1

	stw	r7,0(r4)

	blr

  .cfi_endproc

V_FUNCTION_END(__kernel_getcpu)

arch/powerpc/kernel/vdso32/gettimeofday.S

+9 −9
Original line number Diff line number Diff line
@@ -32,10 +32,9 @@ V_FUNCTION_BEGIN(__kernel_gettimeofday) 
	mflr	r12

  .cfi_register lr,r12



	mr	r10,r3			/* r10 saves tv */

	mr.	r10,r3			/* r10 saves tv */

	mr	r11,r4			/* r11 saves tz */

	get_datapage	r9, r0

	cmplwi	r10,0			/* check if tv is NULL */

	beq	3f

	LOAD_REG_IMMEDIATE(r7, 1000000)	/* load up USEC_PER_SEC */

	bl	__do_get_tspec@local	/* get sec/usec from tb & kernel */
@@ -43,15 +42,16 @@ V_FUNCTION_BEGIN(__kernel_gettimeofday) 
	stw	r4,TVAL32_TV_USEC(r10)



3:	cmplwi	r11,0			/* check if tz is NULL */

	beq	1f

	mtlr	r12

	crclr	cr0*4+so

	li	r3,0

	beqlr



	lwz	r4,CFG_TZ_MINUTEWEST(r9)/* fill tz */

	lwz	r5,CFG_TZ_DSTTIME(r9)

	stw	r4,TZONE_TZ_MINWEST(r11)

	stw	r5,TZONE_TZ_DSTTIME(r11)



1:	mtlr	r12

	crclr	cr0*4+so

	li	r3,0

	blr

  .cfi_endproc

V_FUNCTION_END(__kernel_gettimeofday)
@@ -245,10 +245,10 @@ V_FUNCTION_BEGIN(__kernel_time) 
	lwz	r3,STAMP_XTIME_SEC+LOPART(r9)



	cmplwi	r11,0			/* check if t is NULL */

	beq	2f

	stw	r3,0(r11)		/* store result at *t */

2:	mtlr	r12

	mtlr	r12

	crclr	cr0*4+so

	beqlr

	stw	r3,0(r11)		/* store result at *t */

	blr

  .cfi_endproc

V_FUNCTION_END(__kernel_time)

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