[PATCH v2 1/2] arm64/traps: Replace this_cpu_* with raw_cpu_* in panic_bad_stack()
From: Zhen Lei <hidden>
Date: 2022-08-26 09:57:15
Also in:
lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
The hardware automatically disable the IRQ interrupt before jumping to the interrupt or exception vector. Therefore, the preempt_disable() operation in this_cpu_read() after macro expansion is unnecessary for exception handler. Use raw_cpu_* instead of this_cpu_* can reduce a few lines of assembly code. To be honest, the fewer unnecessary operations in exception handler, the better. Signed-off-by: Zhen Lei <redacted> --- arch/arm64/kernel/traps.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index b7fed33981f7b76..e6b6f4650e3d895 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c@@ -871,8 +871,8 @@ DEFINE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], overflow_stack) void panic_bad_stack(struct pt_regs *regs, unsigned long esr, unsigned long far) { unsigned long tsk_stk = (unsigned long)current->stack; - unsigned long irq_stk = (unsigned long)this_cpu_read(irq_stack_ptr); - unsigned long ovf_stk = (unsigned long)this_cpu_ptr(overflow_stack); + unsigned long irq_stk = (unsigned long)raw_cpu_read(irq_stack_ptr); + unsigned long ovf_stk = (unsigned long)raw_cpu_ptr(overflow_stack); console_verbose(); pr_emerg("Insufficient stack space to handle exception!");
--
2.25.1
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