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arm64: entry: Save some nops when CONFIG_ARM64_PSEUDO_NMI is not set

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Arm64 pseudo-NMI feature code brings some additional nops
when CONFIG_ARM64_PSEUDO_NMI is not set, which is not
necessary. So add necessary ifdeffery to avoid it.

Signed-off-by: He Ying <heying24@huawei.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220112032410.29231-1-heying24@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
He Ying 2022-01-11 22:24:10 -05:00 committed by Will Deacon
parent dfd42facf1
commit 3352a5556f
1 changed files with 4 additions and 0 deletions
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4
arch/arm64/kernel/entry.S
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@ -300,6 +300,7 @@ alternative_else_nop_endif
str w21, [sp, #S_SYSCALLNO]
.endif
#ifdef CONFIG_ARM64_PSEUDO_NMI
/* Save pmr */
alternative_if ARM64_HAS_IRQ_PRIO_MASKING
mrs_s x20, SYS_ICC_PMR_EL1
@ -307,6 +308,7 @@ alternative_if ARM64_HAS_IRQ_PRIO_MASKING
mov x20, #GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET
msr_s SYS_ICC_PMR_EL1, x20
alternative_else_nop_endif
#endif
/* Re-enable tag checking (TCO set on exception entry) */
#ifdef CONFIG_ARM64_MTE
@ -330,6 +332,7 @@ alternative_else_nop_endif
disable_daif
.endif
#ifdef CONFIG_ARM64_PSEUDO_NMI
/* Restore pmr */
alternative_if ARM64_HAS_IRQ_PRIO_MASKING
ldr x20, [sp, #S_PMR_SAVE]
@ -339,6 +342,7 @@ alternative_if ARM64_HAS_IRQ_PRIO_MASKING
dsb sy // Ensure priority change is seen by redistributor
.L__skip_pmr_sync\@:
alternative_else_nop_endif
#endif
ldp x21, x22, [sp, #S_PC] // load ELR, SPSR