From 144beb2f53894283e0a8a4e6ef32d42b17fc34fd Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 15 Jul 2014 21:15:36 +1000 Subject: [PATCH] powerpc: Update comments in irqflags.h The comment on TRACE_ENABLE_INTS is incorrect, and appears to have always been incorrect since the code was merged. It probably came from an original out-of-tree patch. Replace it with something that's correct. Also propagate the message to RECONCILE_IRQ_STATE(), because it's potentially subtle. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/irqflags.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/include/asm/irqflags.h b/arch/powerpc/include/asm/irqflags.h index e20eb95429a8..f2149066fe5d 100644 --- a/arch/powerpc/include/asm/irqflags.h +++ b/arch/powerpc/include/asm/irqflags.h @@ -32,9 +32,8 @@ #endif /* - * Most of the CPU's IRQ-state tracing is done from assembly code; we - * have to call a C function so call a wrapper that saves all the - * C-clobbered registers. + * These are calls to C code, so the caller must be prepared for volatiles to + * be clobbered. */ #define TRACE_ENABLE_INTS TRACE_WITH_FRAME_BUFFER(trace_hardirqs_on) #define TRACE_DISABLE_INTS TRACE_WITH_FRAME_BUFFER(trace_hardirqs_off) @@ -42,6 +41,9 @@ /* * This is used by assembly code to soft-disable interrupts first and * reconcile irq state. + * + * NB: This may call C code, so the caller must be prepared for volatiles to + * be clobbered. */ #define RECONCILE_IRQ_STATE(__rA, __rB) \ lbz __rA,PACASOFTIRQEN(r13); \ -- 2.20.1