Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752120Ab3ILOFA (ORCPT ); Thu, 12 Sep 2013 10:05:00 -0400 Received: from mail-pa0-f50.google.com ([209.85.220.50]:53603 "EHLO mail-pa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751359Ab3ILOE6 (ORCPT ); Thu, 12 Sep 2013 10:04:58 -0400 Message-ID: <5231C9F3.4060208@gmail.com> Date: Thu, 12 Sep 2013 22:04:35 +0800 From: Jiang Liu User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130510 Thunderbird/17.0.6 MIME-Version: 1.0 To: "Srivatsa S. Bhat" CC: Andrew Morton , Benjamin Herrenschmidt , Paul Mackerras , Shaohua Li , linux-arch@vger.kernel.org, Jiri Kosina , Peter Zijlstra , Wang YanQing , Steven Rostedt , linux-kernel@vger.kernel.org, Ingo Molnar , linuxppc-dev@lists.ozlabs.org, Jiang Liu , Preeti U Murthy , Deepthi Dharwar , Vaidyanathan Srinivasan , "Paul E. McKenney" Subject: Re: [RFC PATCH v2 15/25] smp, ppc: kill SMP single function call interrupt References: <1378915649-16395-1-git-send-email-liuj97@gmail.com> <1378915649-16395-16-git-send-email-liuj97@gmail.com> <5230CC84.1010503@linux.vnet.ibm.com> In-Reply-To: <5230CC84.1010503@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4502 Lines: 119 On 09/12/2013 04:03 AM, Srivatsa S. Bhat wrote: > On 09/11/2013 09:37 PM, Jiang Liu wrote: >> From: Jiang Liu >> >> Commit 9a46ad6d6df3b54 "smp: make smp_call_function_many() use logic >> similar to smp_call_function_single()" has unified the way to handle >> single and multiple cross-CPU function calls. Now only one interrupt >> is needed for architecture specific code to support generic SMP function >> call interfaces, so kill the redundant single function call interrupt. >> >> Signed-off-by: Jiang Liu >> Cc: Jiang Liu >> --- > > It turns out that freeing up the IPI slot in powerpc is very useful, since > we actually wanted a slot for some other use-case (and there are only 4 slots > available on powerpc). > > Here are the patches which achieve that: > http://marc.info/?l=linuxppc-embedded&m=137886807502898&w=2 > http://marc.info/?l=linuxppc-embedded&m=137886811502909&w=2 Hi Srivatsa, That's great and I will drop this patch from my series. Could you please to kill call_function_single_action() instead of call_function_action()? Please refer to http://lkml.org/lkml/2013/9/11/579 Regards! Gerry > > So, can you kindly consider dropping the powerpc patch from your series, > if that is OK with you? Thanks! > > BTW, after doing the powerpc cleanup, even I had thought about killing one > of the smp-function variants in various architectures, but never got around > to do it. But now that you have posted the series which does that, I'll try > to review them. > > Thank you! > > Regards, > Srivatsa S. Bhat > >> arch/powerpc/include/asm/smp.h | 3 +-- >> arch/powerpc/kernel/smp.c | 12 +----------- >> 2 files changed, 2 insertions(+), 13 deletions(-) >> >> diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h >> index 48cfc85..53faa03 100644 >> --- a/arch/powerpc/include/asm/smp.h >> +++ b/arch/powerpc/include/asm/smp.h >> @@ -119,8 +119,7 @@ extern int cpu_to_core_id(int cpu); >> * in /proc/interrupts will be wrong!!! --Troy */ >> #define PPC_MSG_CALL_FUNCTION 0 >> #define PPC_MSG_RESCHEDULE 1 >> -#define PPC_MSG_CALL_FUNC_SINGLE 2 >> -#define PPC_MSG_DEBUGGER_BREAK 3 >> +#define PPC_MSG_DEBUGGER_BREAK 2 >> >> /* for irq controllers that have dedicated ipis per message (4) */ >> extern int smp_request_message_ipi(int virq, int message); >> diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c >> index 38b0ba6..0c53b10 100644 >> --- a/arch/powerpc/kernel/smp.c >> +++ b/arch/powerpc/kernel/smp.c >> @@ -123,12 +123,6 @@ static irqreturn_t reschedule_action(int irq, void *data) >> return IRQ_HANDLED; >> } >> >> -static irqreturn_t call_function_single_action(int irq, void *data) >> -{ >> - generic_smp_call_function_single_interrupt(); >> - return IRQ_HANDLED; >> -} >> - >> static irqreturn_t debug_ipi_action(int irq, void *data) >> { >> if (crash_ipi_function_ptr) { >> @@ -146,14 +140,12 @@ static irqreturn_t debug_ipi_action(int irq, void *data) >> static irq_handler_t smp_ipi_action[] = { >> [PPC_MSG_CALL_FUNCTION] = call_function_action, >> [PPC_MSG_RESCHEDULE] = reschedule_action, >> - [PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action, >> [PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action, >> }; >> >> const char *smp_ipi_name[] = { >> [PPC_MSG_CALL_FUNCTION] = "ipi call function", >> [PPC_MSG_RESCHEDULE] = "ipi reschedule", >> - [PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single", >> [PPC_MSG_DEBUGGER_BREAK] = "ipi debugger", >> }; >> >> @@ -225,8 +217,6 @@ irqreturn_t smp_ipi_demux(void) >> generic_smp_call_function_interrupt(); >> if (all & (1 << (24 - 8 * PPC_MSG_RESCHEDULE))) >> scheduler_ipi(); >> - if (all & (1 << (24 - 8 * PPC_MSG_CALL_FUNC_SINGLE))) >> - generic_smp_call_function_single_interrupt(); >> if (all & (1 << (24 - 8 * PPC_MSG_DEBUGGER_BREAK))) >> debug_ipi_action(0, NULL); >> #else >> @@ -257,7 +247,7 @@ EXPORT_SYMBOL_GPL(smp_send_reschedule); >> >> void arch_send_call_function_single_ipi(int cpu) >> { >> - do_message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE); >> + do_message_pass(cpu, PPC_MSG_CALL_FUNCTION); >> } >> >> void arch_send_call_function_ipi_mask(const struct cpumask *mask) >> > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/