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powerpc/booke64: Eemove mfspr srr1 duplicate in exception prolog

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Refactor exception prolog to get rid of mfspr srr1 duplicate. This was
introduced by KVM integration, with DO_KVM macro logic expecting srr1 value
earlier in r11.
Reserve r11 to hold srr1's value also required at the end of the prolog and
free up r10 to serve as spare in addition macros.
For syscalls case this change does not add any performance penalty. For irq
soft-disabled case the change adds a store/load of conditional register value
to/from a paca slot. Paca slots fit in one 64-byte cache line so these
additional operations have little impact on performance.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Mihai Caraman 2012-08-06 03:27:06 +00:00 • committed by Benjamin Herrenschmidt
parent fecff0f724
commit 79b5c8dbaa
1 changed files with 35 additions and 38 deletions
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73
arch/powerpc/kernel/exceptions-64e.S
View file

@ -45,10 +45,9 @@
mfcr r10; /* save CR */ \ mfcr r10; /* save CR */ \
mfspr r11,SPRN_##type##_SRR1;/* what are we coming from */ \ mfspr r11,SPRN_##type##_SRR1;/* what are we coming from */ \
DO_KVM intnum,SPRN_##type##_SRR1; /* KVM hook */ \ DO_KVM intnum,SPRN_##type##_SRR1; /* KVM hook */ \
stw r10,PACA_EX##type+EX_CR(r13); /* save old CR in the PACA */ \
addition; /* additional code for that exc. */ \ addition; /* additional code for that exc. */ \
std r1,PACA_EX##type+EX_R1(r13); /* save old r1 in the PACA */ \ std r1,PACA_EX##type+EX_R1(r13); /* save old r1 in the PACA */ \
stw r10,PACA_EX##type+EX_CR(r13); /* save old CR in the PACA */ \
mfspr r11,SPRN_##type##_SRR1;/* what are we coming from */ \
type##_SET_KSTACK; /* get special stack if necessary */\ type##_SET_KSTACK; /* get special stack if necessary */\
andi. r10,r11,MSR_PR; /* save stack pointer */ \ andi. r10,r11,MSR_PR; /* save stack pointer */ \
beq 1f; /* branch around if supervisor */ \ beq 1f; /* branch around if supervisor */ \
@ -109,8 +108,8 @@
#define PROLOG_ADDITION_NONE_MC(n) #define PROLOG_ADDITION_NONE_MC(n)
#define PROLOG_ADDITION_MASKABLE_GEN(n) \ #define PROLOG_ADDITION_MASKABLE_GEN(n) \
lbz r11,PACASOFTIRQEN(r13); /* are irqs soft-disabled ? */ \ lbz r10,PACASOFTIRQEN(r13); /* are irqs soft-disabled ? */ \
cmpwi cr0,r11,0; /* yes -> go out of line */ \ cmpwi cr0,r10,0; /* yes -> go out of line */ \
beq masked_interrupt_book3e_##n beq masked_interrupt_book3e_##n
#define PROLOG_ADDITION_2REGS_GEN(n) \ #define PROLOG_ADDITION_2REGS_GEN(n) \
@ -624,44 +623,42 @@ kernel_dbg_exc:
* accordingly and if the interrupt is level sensitive, we hard disable * accordingly and if the interrupt is level sensitive, we hard disable
*/ */
masked_interrupt_book3e_0x500: .macro masked_interrupt_book3e paca_irq full_mask
/* XXX When adding support for EPR, use PACA_IRQ_EE_EDGE */
li r11,PACA_IRQ_EE
b masked_interrupt_book3e_full_mask
masked_interrupt_book3e_0x900:
ACK_DEC(r11);
li r11,PACA_IRQ_DEC
b masked_interrupt_book3e_no_mask
masked_interrupt_book3e_0x980:
ACK_FIT(r11);
li r11,PACA_IRQ_DEC
b masked_interrupt_book3e_no_mask
masked_interrupt_book3e_0x280:
masked_interrupt_book3e_0x2c0:
li r11,PACA_IRQ_DBELL
b masked_interrupt_book3e_no_mask
masked_interrupt_book3e_no_mask:
mtcr r10
lbz r10,PACAIRQHAPPENED(r13) lbz r10,PACAIRQHAPPENED(r13)
or r10,r10,r11 ori r10,r10,\paca_irq
stb r10,PACAIRQHAPPENED(r13) stb r10,PACAIRQHAPPENED(r13)
b 1f
masked_interrupt_book3e_full_mask: .if \full_mask == 1
mtcr r10 rldicl r10,r11,48,1 /* clear MSR_EE */
lbz r10,PACAIRQHAPPENED(r13) rotldi r11,r10,16
or r10,r10,r11 mtspr SPRN_SRR1,r11
stb r10,PACAIRQHAPPENED(r13) .endif
mfspr r10,SPRN_SRR1
rldicl r11,r10,48,1 /* clear MSR_EE */ lwz r11,PACA_EXGEN+EX_CR(r13)
rotldi r10,r11,16 mtcr r11
mtspr SPRN_SRR1,r10 ld r10,PACA_EXGEN+EX_R10(r13)
1: ld r10,PACA_EXGEN+EX_R10(r13); ld r11,PACA_EXGEN+EX_R11(r13)
ld r11,PACA_EXGEN+EX_R11(r13); mfspr r13,SPRN_SPRG_GEN_SCRATCH
mfspr r13,SPRN_SPRG_GEN_SCRATCH;
rfi rfi
b . b .
.endm
masked_interrupt_book3e_0x500:
// XXX When adding support for EPR, use PACA_IRQ_EE_EDGE
masked_interrupt_book3e PACA_IRQ_EE 1
masked_interrupt_book3e_0x900:
ACK_DEC(r10);
masked_interrupt_book3e PACA_IRQ_DEC 0
masked_interrupt_book3e_0x980:
ACK_FIT(r10);
masked_interrupt_book3e PACA_IRQ_DEC 0
masked_interrupt_book3e_0x280:
masked_interrupt_book3e_0x2c0:
masked_interrupt_book3e PACA_IRQ_DBELL 0
/* /*
* Called from arch_local_irq_enable when an interrupt needs * Called from arch_local_irq_enable when an interrupt needs
* to be resent. r3 contains either 0x500,0x900,0x260 or 0x280 * to be resent. r3 contains either 0x500,0x900,0x260 or 0x280