From patchwork Tue Jul 15 11:15:36 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Ellerman X-Patchwork-Id: 369962 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id C12E9140142 for ; Tue, 15 Jul 2014 21:16:25 +1000 (EST) Received: from ozlabs.org (ozlabs.org [103.22.144.67]) by lists.ozlabs.org (Postfix) with ESMTP id ACD651A0C51 for ; Tue, 15 Jul 2014 21:16:25 +1000 (EST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from ozlabs.org (ozlabs.org [103.22.144.67]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 690FD1A0B92 for ; Tue, 15 Jul 2014 21:15:44 +1000 (EST) Received: by ozlabs.org (Postfix) id 5759F14011B; Tue, 15 Jul 2014 21:15:44 +1000 (EST) Delivered-To: linuxppc-dev@ozlabs.org Received: by ozlabs.org (Postfix, from userid 1034) id 4FD0B140142; Tue, 15 Jul 2014 21:15:44 +1000 (EST) From: Michael Ellerman To: Subject: [PATCH 1/3] powerpc: Update comments in irqflags.h Date: Tue, 15 Jul 2014 21:15:36 +1000 Message-Id: <1405422938-27608-1-git-send-email-mpe@ellerman.id.au> X-Mailer: git-send-email 1.9.1 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.16 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" 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 --- 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); \