Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755084Ab3GYJGH (ORCPT ); Thu, 25 Jul 2013 05:06:07 -0400 Received: from e28smtp02.in.ibm.com ([122.248.162.2]:55130 "EHLO e28smtp02.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755098Ab3GYJFl (ORCPT ); Thu, 25 Jul 2013 05:05:41 -0400 Subject: [RFC PATCH 1/5] powerpc: Free up the IPI message slot of ipi call function (PPC_MSG_CALL_FUNC) To: benh@kernel.crashing.org, paul.gortmaker@windriver.com, paulus@samba.org, shangw@linux.vnet.ibm.com, galak@kernel.crashing.org, fweisbec@gmail.com, paulmck@linux.vnet.ibm.com, michael@ellerman.id.au, arnd@arndb.de, linux-pm@vger.kernel.org, rostedt@goodmis.org, rjw@sisk.pl, john.stultz@linaro.org, tglx@linutronix.de, chenhui.zhao@freescale.com, deepthi@linux.vnet.ibm.com, geoff@infradead.org, linux-kernel@vger.kernel.org, srivatsa.bhat@linux.vnet.ibm.com, schwidefsky@de.ibm.com, svaidy@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org From: Preeti U Murthy Date: Thu, 25 Jul 2013 14:32:46 +0530 Message-ID: <20130725090246.12500.35232.stgit@preeti.in.ibm.com> In-Reply-To: <20130725090016.12500.28888.stgit@preeti.in.ibm.com> References: <20130725090016.12500.28888.stgit@preeti.in.ibm.com> User-Agent: StGit/0.16-38-g167d MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13072508-5816-0000-0000-000009162A93 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4559 Lines: 117 From: Srivatsa S. Bhat The IPI handlers for both PPC_MSG_CALL_FUNC and PPC_MSG_CALL_FUNC_SINGLE map to a common implementation - generic_smp_call_function_single_interrupt(). So, we can consolidate them and save one of the IPI message slots, (which are precious, since only 4 of those slots are available). So, implement the functionality of PPC_MSG_CALL_FUNC using PPC_MSG_CALL_FUNC_SINGLE itself and release its IPI message slot, so that it can be used for something else in the future, if desired. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Preeti U Murthy --- arch/powerpc/include/asm/smp.h | 2 +- arch/powerpc/kernel/smp.c | 12 +++++------- arch/powerpc/platforms/cell/interrupt.c | 2 +- arch/powerpc/platforms/ps3/smp.c | 2 +- 4 files changed, 8 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h index ffbaabe..51bf017 100644 --- a/arch/powerpc/include/asm/smp.h +++ b/arch/powerpc/include/asm/smp.h @@ -117,7 +117,7 @@ extern int cpu_to_core_id(int cpu); * * Make sure this matches openpic_request_IPIs in open_pic.c, or what shows up * in /proc/interrupts will be wrong!!! --Troy */ -#define PPC_MSG_CALL_FUNCTION 0 +#define PPC_MSG_UNUSED 0 #define PPC_MSG_RESCHEDULE 1 #define PPC_MSG_CALL_FUNC_SINGLE 2 #define PPC_MSG_DEBUGGER_BREAK 3 diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 38b0ba6..bc41e9f 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -111,9 +111,9 @@ int smp_generic_kick_cpu(int nr) } #endif /* CONFIG_PPC64 */ -static irqreturn_t call_function_action(int irq, void *data) +static irqreturn_t unused_action(int irq, void *data) { - generic_smp_call_function_interrupt(); + /* This slot is unused and hence available for use, if needed */ return IRQ_HANDLED; } @@ -144,14 +144,14 @@ 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_UNUSED] = unused_action, /* Slot available for future use */ [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_UNUSED] = "ipi unused", [PPC_MSG_RESCHEDULE] = "ipi reschedule", [PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single", [PPC_MSG_DEBUGGER_BREAK] = "ipi debugger", @@ -221,8 +221,6 @@ irqreturn_t smp_ipi_demux(void) all = xchg(&info->messages, 0); #ifdef __BIG_ENDIAN - if (all & (1 << (24 - 8 * PPC_MSG_CALL_FUNCTION))) - 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))) @@ -265,7 +263,7 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask) unsigned int cpu; for_each_cpu(cpu, mask) - do_message_pass(cpu, PPC_MSG_CALL_FUNCTION); + do_message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE); } #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC) diff --git a/arch/powerpc/platforms/cell/interrupt.c b/arch/powerpc/platforms/cell/interrupt.c index 2d42f3b..28166e4 100644 --- a/arch/powerpc/platforms/cell/interrupt.c +++ b/arch/powerpc/platforms/cell/interrupt.c @@ -213,7 +213,7 @@ static void iic_request_ipi(int msg) void iic_request_IPIs(void) { - iic_request_ipi(PPC_MSG_CALL_FUNCTION); + iic_request_ipi(PPC_MSG_UNUSED); iic_request_ipi(PPC_MSG_RESCHEDULE); iic_request_ipi(PPC_MSG_CALL_FUNC_SINGLE); iic_request_ipi(PPC_MSG_DEBUGGER_BREAK); diff --git a/arch/powerpc/platforms/ps3/smp.c b/arch/powerpc/platforms/ps3/smp.c index 4b35166..488f069 100644 --- a/arch/powerpc/platforms/ps3/smp.c +++ b/arch/powerpc/platforms/ps3/smp.c @@ -74,7 +74,7 @@ static int __init ps3_smp_probe(void) * to index needs to be setup. */ - BUILD_BUG_ON(PPC_MSG_CALL_FUNCTION != 0); + BUILD_BUG_ON(PPC_MSG_UNUSED != 0); BUILD_BUG_ON(PPC_MSG_RESCHEDULE != 1); BUILD_BUG_ON(PPC_MSG_CALL_FUNC_SINGLE != 2); BUILD_BUG_ON(PPC_MSG_DEBUGGER_BREAK != 3); -- 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/