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Subject[PATCH] arm64: entry: Save some nops when CONFIG_ARM64_PSEUDO_NMI is not set
Date
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>
---
arch/arm64/kernel/entry.S | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 2f69ae43941d..ffc32d3d909a 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -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

--
2.17.1
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