Commit eb595eca authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/32: Remove the counter in global_dbcr0 



global_dbcr0 has two parts, 4 bytes to save/restore the
value of SPRN_DBCR0, and 4 bytes that are incremented/decremented
everytime something is saving/loading the above value.

This counter is only incremented/decremented, its value is never
used and never read.

Remove the counter and devide the size of global_dbcr0 by 2.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7e381dc58b3f583556cfab37ba5d813bfd5cce1e.1612796617.git.christophe.leroy@csgroup.eu
parent 4d67facb

arch/powerpc/kernel/entry_32.S

+3 −9
Original line number Diff line number Diff line
@@ -175,14 +175,11 @@ transfer_to_handler: 
	addi	r11,r11,global_dbcr0@l

#ifdef CONFIG_SMP

	lwz	r9,TASK_CPU(r2)

	slwi	r9,r9,3

	slwi	r9,r9,2

	add	r11,r11,r9

#endif

	lwz	r12,0(r11)

	mtspr	SPRN_DBCR0,r12

	lwz	r12,4(r11)

	addi	r12,r12,-1

	stw	r12,4(r11)

#endif



	b	3f
@@ -981,14 +978,11 @@ load_dbcr0: 
	addi	r11,r11,global_dbcr0@l

#ifdef CONFIG_SMP

	lwz	r9,TASK_CPU(r2)

	slwi	r9,r9,3

	slwi	r9,r9,2

	add	r11,r11,r9

#endif

	stw	r10,0(r11)

	mtspr	SPRN_DBCR0,r0

	lwz	r10,4(r11)

	addi	r10,r10,1

	stw	r10,4(r11)

	li	r11,-1

	mtspr	SPRN_DBSR,r11	/* clear all pending debug events */

	blr
@@ -997,7 +991,7 @@ load_dbcr0: 
	.align	4

	.global global_dbcr0

global_dbcr0:

	.space	8*NR_CPUS

	.space	4*NR_CPUS

	.previous

#endif /* !(CONFIG_4xx || CONFIG_BOOKE) */

arch/powerpc/kernel/head_32.h

+0 −3
Original line number Diff line number Diff line
@@ -166,9 +166,6 @@ 
	addi	r11,r11,global_dbcr0@l

	lwz	r12,0(r11)

	mtspr	SPRN_DBCR0,r12

	lwz	r12,4(r11)

	addi	r12,r12,-1

	stw	r12,4(r11)

3:

#endif

	b	transfer_to_syscall		/* jump to handler */

arch/powerpc/kernel/head_booke.h

+1 −4
Original line number Diff line number Diff line
@@ -142,14 +142,11 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) 
	addi	r11,r11,global_dbcr0@l

#ifdef CONFIG_SMP

	lwz	r10, TASK_CPU(r2)

	slwi	r10, r10, 3

	slwi	r10, r10, 2

	add	r11, r11, r10

#endif

	lwz	r12,0(r11)

	mtspr	SPRN_DBCR0,r12

	lwz	r12,4(r11)

	addi	r12,r12,-1

	stw	r12,4(r11)



3:

	b	transfer_to_syscall	/* jump to handler */