From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 0/4]: Respin local_irq_*_nmi() stuff. Date: Tue, 13 Apr 2010 00:56:40 -0700 (PDT) Message-ID: <20100413.005640.48990319.davem@davemloft.net> References: <20100409.160132.216116766.davem@davemloft.net> <20100412.220838.132238558.davem@davemloft.net> <1271144938.4807.925.camel@twins> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:46192 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751305Ab0DMH4g (ORCPT ); Tue, 13 Apr 2010 03:56:36 -0400 In-Reply-To: <1271144938.4807.925.camel@twins> Sender: linux-arch-owner@vger.kernel.org List-ID: To: peterz@infradead.org Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, sparclinux@vger.kernel.org From: Peter Zijlstra Date: Tue, 13 Apr 2010 09:48:58 +0200 > Care to enlighten the curious amongst us as to what exactly you're > doing in the sparc code? >From 0c25e9e6cbe7b233bb91d14d0e2c258bf8e6ec83 Mon Sep 17 00:00:00 2001 From: David S. Miller Date: Mon, 12 Apr 2010 22:21:52 -0700 Subject: [PATCH 2/2] sparc64: Adjust __raw_local_irq_save() to cooperate in NMIs. If we are in an NMI then doing a plain raw_local_irq_disable() will write PIL_NORMAL_MAX into %pil, which is lower than PIL_NMI, and thus we'll re-enable NMIs and recurse. Doing a simple: %pil = %pil | PIL_NORMAL_MAX does what we want, if we're already at PIL_NMI (15) we leave it at that setting, else we set it to PIL_NORMAL_MAX (14). This should get the function tracer working on sparc64. Signed-off-by: David S. Miller --- arch/sparc/include/asm/irqflags_64.h | 14 ++++++++++++-- 1 files changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/sparc/include/asm/irqflags_64.h b/arch/sparc/include/asm/irqflags_64.h index 8b49bf9..a16e94c 100644 --- a/arch/sparc/include/asm/irqflags_64.h +++ b/arch/sparc/include/asm/irqflags_64.h @@ -76,9 +76,19 @@ static inline int raw_irqs_disabled(void) */ static inline unsigned long __raw_local_irq_save(void) { - unsigned long flags = __raw_local_save_flags(); + unsigned long flags, tmp; - raw_local_irq_disable(); + /* Disable interrupts to PIL_NORMAL_MAX unless we already + * are using PIL_NMI, in which case PIL_NMI is retained. + */ + __asm__ __volatile__( + "rdpr %%pil, %0\n\t" + "or %0, %2, %1\n\t" + "wrpr %1, 0x0, %%pil" + : "=r" (flags), "=r" (tmp) + : "i" (PIL_NORMAL_MAX) + : "memory" + ); return flags; } -- 1.7.0.4