From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3scvxV3006zDsd8 for ; Mon, 19 Sep 2016 15:45:34 +1000 (AEST) Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u8J5hSfo013463 for ; Mon, 19 Sep 2016 01:45:32 -0400 Received: from e23smtp07.au.ibm.com (e23smtp07.au.ibm.com [202.81.31.140]) by mx0a-001b2d01.pphosted.com with ESMTP id 25h1wdqyq3-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 19 Sep 2016 01:45:32 -0400 Received: from localhost by e23smtp07.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 19 Sep 2016 15:45:29 +1000 Received: from d23relay08.au.ibm.com (d23relay08.au.ibm.com [9.185.71.33]) by d23dlp01.au.ibm.com (Postfix) with ESMTP id D71C82CE8056 for ; Mon, 19 Sep 2016 15:45:26 +1000 (EST) Received: from d23av05.au.ibm.com (d23av05.au.ibm.com [9.190.234.119]) by d23relay08.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u8J5jQHS5112170 for ; Mon, 19 Sep 2016 15:45:26 +1000 Received: from d23av05.au.ibm.com (localhost [127.0.0.1]) by d23av05.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u8J5jQbE004796 for ; Mon, 19 Sep 2016 15:45:26 +1000 Subject: Re: [PATCH 06/13] powerpc: reverse the soft_enable logic To: Nicholas Piggin References: <1473944523-624-1-git-send-email-maddy@linux.vnet.ibm.com> <1473944523-624-7-git-send-email-maddy@linux.vnet.ibm.com> <20160916200537.50562560@roar.ozlabs.ibm.com> Cc: benh@kernel.crashing.org, mpe@ellerman.id.au, anton@samba.org, paulus@samba.org, linuxppc-dev@lists.ozlabs.org From: Madhavan Srinivasan Date: Mon, 19 Sep 2016 11:15:24 +0530 MIME-Version: 1.0 In-Reply-To: <20160916200537.50562560@roar.ozlabs.ibm.com> Content-Type: text/plain; charset=windows-1252; format=flowed Message-Id: List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Friday 16 September 2016 03:35 PM, Nicholas Piggin wrote: > On Thu, 15 Sep 2016 18:31:56 +0530 > Madhavan Srinivasan wrote: > >> "paca->soft_enabled" is used as a flag to mask some of interrupts. >> Currently supported flags values and their details: >> >> soft_enabled MSR[EE] >> >> 0 0 Disabled (PMI and HMI not masked) >> 1 1 Enabled >> >> "paca->soft_enabled" is initialized to 1 to make the interripts as >> enabled. arch_local_irq_disable() will toggle the value when interrupts >> needs to disbled. At this point, the interrupts are not actually disabled, >> instead, interrupt vector has code to check for the flag and mask it when it occurs. >> By "mask it", it update interrupt paca->irq_happened and return. >> arch_local_irq_restore() is called to re-enable interrupts, which checks and >> replays interrupts if any occured. >> >> Now, as mentioned, current logic doesnot mask "performance monitoring interrupts" >> and PMIs are implemented as NMI. But this patchset depends on local_irq_* >> for a successful local_* update. Meaning, mask all possible interrupts during >> local_* update and replay them after the update. >> >> So the idea here is to reserve the "paca->soft_enabled" logic. New values and >> details: >> >> soft_enabled MSR[EE] >> >> 1 0 Disabled (PMI and HMI not masked) >> 0 1 Enabled >> >> Reason for the this change is to create foundation for a third flag value "2" >> for "soft_enabled" to add support to mask PMIs. When ->soft_enabled is >> set to a value "2", PMI interrupts are mask and when set to a value >> of "1", PMI are not mask. >> >> Signed-off-by: Madhavan Srinivasan >> --- >> arch/powerpc/include/asm/hw_irq.h | 4 ++-- >> arch/powerpc/kernel/entry_64.S | 5 ++--- >> 2 files changed, 4 insertions(+), 5 deletions(-) >> >> diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h >> index dc3c248f9244..fd9b421f9020 100644 >> --- a/arch/powerpc/include/asm/hw_irq.h >> +++ b/arch/powerpc/include/asm/hw_irq.h >> @@ -30,8 +30,8 @@ >> /* >> * flags for paca->soft_enabled >> */ >> -#define IRQ_DISABLE_MASK_NONE 1 >> -#define IRQ_DISABLE_MASK_LINUX 0 >> +#define IRQ_DISABLE_MASK_NONE 0 >> +#define IRQ_DISABLE_MASK_LINUX 1 >> >> #endif /* CONFIG_PPC64 */ >> >> diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S >> index aef7b64cbbeb..879aeb11ad29 100644 >> --- a/arch/powerpc/kernel/entry_64.S >> +++ b/arch/powerpc/kernel/entry_64.S >> @@ -131,8 +131,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) >> */ >> #if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_BUG) >> lbz r10,PACASOFTIRQEN(r13) >> - xori r10,r10,IRQ_DISABLE_MASK_NONE >> -1: tdnei r10,0 >> +1: tdnei r10,IRQ_DISABLE_MASK_NONE >> EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING >> #endif >> >> @@ -1012,7 +1011,7 @@ _GLOBAL(enter_rtas) >> * check it with the asm equivalent of WARN_ON >> */ >> lbz r0,PACASOFTIRQEN(r13) >> -1: tdnei r0,IRQ_DISABLE_MASK_LINUX >> +1: tdeqi r0,IRQ_DISABLE_MASK_NONE >> EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING >> #endif >> > We specifically want to ensure that _LINUX interrupts are disabled > here. Not that we allow masking of others without _LINUX now, but > current behavior is checking that LINUX ones are masked. > > Otherwise it seems okay. > > It might be nice after this series to do a pass and rename > soft_enabled to soft_masked. Yes definitely, I do have it in my todo. Maddy > > Reviewed-by: Nicholas Piggin >