[RFC PATCH v3 00/19] simplify generic cross CPU function call implementation

[RFC PATCH v3 00/19] simplify generic cross CPU function call implementation

[Jiang Liu]

Resend for v3.14 merge window. Patch for ARC, MIPS and PARISC has been
merged into v3.13.

Since commit 9a46ad6d6df3b54 "smp: make smp_call_function_many() use
logic similar to smp_call_function_single()", single and multiple
(mask version) cross CPU function calls are handled in the same way,
and generic_smp_call_function_interrupt() becomes an aliases of
generic_smp_call_function_single_interrupt(), so only one interrupt
is needed for arch code to support generic SMP function call interfaces.
This patch series simplifies arch code by killing the redundant
interrupt for cross CPU function calls.

We choose to keep generic_smp_call_function_interrupt() instead of
generic_smp_call_function_single_interrupt() because the former is
more generic.

Jiang Liu (19):
  Revert "kernel/smp.c: free related resources when failure occurs in
    hotplug_cfd()"
  Revert "smp: Fix SMP function call empty cpu mask race"
  smp, alpha: kill SMP single function call interrupt
  smp, ARM: kill SMP single function call interrupt
  smp, ARM64: kill SMP single function call interrupt
  smp, blackfin: kill SMP single function call interrupt
  smp, hexagon: kill SMP single function call interrupt
  smp, IA64: kill SMP single function call interrupt
  smp, m32r: kill SMP single function call interrupt
  smp, metag: kill SMP single function call interrupt
  smp, mn10300: kill SMP single function call interrupt
  smp, mn10300: enable arch_send_call_function_ipi_mask()
  smp, s390: prepare for killing
    generic_smp_call_function_single_interrupt()
  smp, sh: kill SMP single function call interrupt
  smp, sparc64: kill SMP single function call interrupt
  smp, sparc: kill SMP single function call interrupt
  smp, tile: kill SMP single function call interrupt
  smp, tile: kill SMP single function call interrupt
  smp, x86: kill SMP single function call interrupt

 arch/alpha/kernel/smp.c                  |  8 +------
 arch/arm/include/asm/hardirq.h           |  2 +-
 arch/arm/kernel/smp.c                    | 10 +--------
 arch/arm64/include/asm/hardirq.h         |  2 +-
 arch/arm64/kernel/smp.c                  | 10 +--------
 arch/blackfin/mach-common/smp.c          |  6 +-----
 arch/hexagon/include/asm/smp.h           |  1 -
 arch/hexagon/kernel/smp.c                |  6 +-----
 arch/ia64/kernel/smp.c                   |  8 ++-----
 arch/m32r/include/asm/smp.h              |  1 -
 arch/m32r/kernel/smp.c                   |  9 +-------
 arch/m32r/kernel/traps.c                 |  3 +--
 arch/metag/include/asm/smp.h             |  2 --
 arch/metag/kernel/smp.c                  |  6 +-----
 arch/mn10300/include/asm/smp.h           |  2 +-
 arch/mn10300/kernel/smp.c                | 19 ++++++++--------
 arch/s390/kernel/smp.c                   | 10 ++++-----
 arch/sh/include/asm/smp.h                |  1 -
 arch/sh/kernel/smp.c                     |  5 +----
 arch/sparc/include/asm/pil.h             |  5 ++---
 arch/sparc/include/asm/smp_32.h          |  4 +---
 arch/sparc/kernel/entry.S                | 10 ++-------
 arch/sparc/kernel/leon_smp.c             | 31 ++++++--------------------
 arch/sparc/kernel/smp_32.c               | 14 ++----------
 arch/sparc/kernel/smp_64.c               | 11 +---------
 arch/sparc/kernel/sun4d_smp.c            | 31 ++++++--------------------
 arch/sparc/kernel/sun4m_smp.c            | 11 ++--------
 arch/sparc/kernel/ttable_64.S            | 12 ++++-------
 arch/sparc/mm/ultra.S                    |  5 -----
 arch/tile/include/asm/smp.h              |  7 +++---
 arch/tile/kernel/smp.c                   |  6 +-----
 arch/x86/include/asm/entry_arch.h        |  1 -
 arch/x86/include/asm/hw_irq.h            |  3 ---
 arch/x86/include/asm/irq_vectors.h       |  7 +++---
 arch/x86/include/asm/trace/irq_vectors.h |  6 ------
 arch/x86/include/asm/xen/events.h        |  1 -
 arch/x86/kernel/entry_64.S               |  2 --
 arch/x86/kernel/irqinit.c                |  4 ----
 arch/x86/kernel/smp.c                    | 24 +--------------------
 arch/x86/xen/smp.c                       | 37 +-------------------------------
 kernel/smp.c                             | 19 ++--------------
 41 files changed, 67 insertions(+), 295 deletions(-)

-- 
1.8.1.2

[RFC PATCH v3 01/19] Revert "kernel/smp.c: free related resources when failure occurs in hotplug_cfd()"

[Jiang Liu]

This reverts commit 60c323699bb308404dcb60e8808531e02651578a.

Commit 60c323699bb30840 fixes a bug introduced by f44310b98ddb7, and we
are going to revert f44310b98ddb7, so revert 60c323699bb30840 first.

Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 kernel/smp.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/kernel/smp.c b/kernel/smp.c
index bd9f940..442d514 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -48,13 +48,10 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
 				cpu_to_node(cpu)))
 			return notifier_from_errno(-ENOMEM);
 		if (!zalloc_cpumask_var_node(&cfd->cpumask_ipi, GFP_KERNEL,
-				cpu_to_node(cpu))) {
-			free_cpumask_var(cfd->cpumask);
+				cpu_to_node(cpu)))
 			return notifier_from_errno(-ENOMEM);
-		}
 		cfd->csd = alloc_percpu(struct call_single_data);
 		if (!cfd->csd) {
-			free_cpumask_var(cfd->cpumask_ipi);
 			free_cpumask_var(cfd->cpumask);
 			return notifier_from_errno(-ENOMEM);
 		}
-- 
1.8.1.2

[RFC PATCH v3 02/19] Revert "smp: Fix SMP function call empty cpu mask race"

[Jiang Liu]

This reverts commit f44310b98ddb7f0d06550d73ed67df5865e3eda5.

Commit f44310b98ddb7 "smp: Fix SMP function call empty cpu mask race"
introduced field call_function_data->cpumask_ipi to resolve a race
condition in smp_call_function_many().

Later commit 9a46ad6d6df3 "smp: make smp_call_function_many() use logic
similar to smp_call_function_single()" fixed the same issue in another
way when optimizing smp_call_function_many(), which then obsoletes
changes introduced by commit f44310b98ddb7. So revert it.

Acked-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 kernel/smp.c | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

diff --git a/kernel/smp.c b/kernel/smp.c
index 442d514..25c19af 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -23,7 +23,6 @@ enum {
 struct call_function_data {
 	struct call_single_data	__percpu *csd;
 	cpumask_var_t		cpumask;
-	cpumask_var_t		cpumask_ipi;
 };
 
 static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_function_data, cfd_data);
@@ -47,9 +46,6 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
 		if (!zalloc_cpumask_var_node(&cfd->cpumask, GFP_KERNEL,
 				cpu_to_node(cpu)))
 			return notifier_from_errno(-ENOMEM);
-		if (!zalloc_cpumask_var_node(&cfd->cpumask_ipi, GFP_KERNEL,
-				cpu_to_node(cpu)))
-			return notifier_from_errno(-ENOMEM);
 		cfd->csd = alloc_percpu(struct call_single_data);
 		if (!cfd->csd) {
 			free_cpumask_var(cfd->cpumask);
@@ -64,7 +60,6 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
 	case CPU_DEAD:
 	case CPU_DEAD_FROZEN:
 		free_cpumask_var(cfd->cpumask);
-		free_cpumask_var(cfd->cpumask_ipi);
 		free_percpu(cfd->csd);
 		break;
 #endif
@@ -245,9 +240,9 @@ int smp_call_function_single(int cpu, smp_call_func_t func, void *info,
 				csd = &__get_cpu_var(csd_data);
 
 			csd_lock(csd);
-
 			csd->func = func;
 			csd->info = info;
+
 			generic_exec_single(cpu, csd, wait);
 		} else {
 			err = -ENXIO;	/* CPU not online */
@@ -399,13 +394,6 @@ void smp_call_function_many(const struct cpumask *mask,
 	if (unlikely(!cpumask_weight(cfd->cpumask)))
 		return;
 
-	/*
-	 * After we put an entry into the list, cfd->cpumask may be cleared
-	 * again when another CPU sends another IPI for a SMP function call, so
-	 * cfd->cpumask will be zero.
-	 */
-	cpumask_copy(cfd->cpumask_ipi, cfd->cpumask);
-
 	for_each_cpu(cpu, cfd->cpumask) {
 		struct call_single_data *csd = per_cpu_ptr(cfd->csd, cpu);
 		struct call_single_queue *dst =
@@ -422,7 +410,7 @@ void smp_call_function_many(const struct cpumask *mask,
 	}
 
 	/* Send a message to all CPUs in the map */
-	arch_send_call_function_ipi_mask(cfd->cpumask_ipi);
+	arch_send_call_function_ipi_mask(cfd->cpumask);
 
 	if (wait) {
 		for_each_cpu(cpu, cfd->cpumask) {
-- 
1.8.1.2

[RFC PATCH v3 03/19] smp, alpha: kill SMP single function call interrupt

[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.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-alpha@vger.kernel.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/alpha/kernel/smp.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c
index 99ac36d..2f24447 100644
--- a/arch/alpha/kernel/smp.c
+++ b/arch/alpha/kernel/smp.c
@@ -63,7 +63,6 @@ static struct {
 enum ipi_message_type {
 	IPI_RESCHEDULE,
 	IPI_CALL_FUNC,
-	IPI_CALL_FUNC_SINGLE,
 	IPI_CPU_STOP,
 };
 
@@ -506,7 +505,6 @@ setup_profiling_timer(unsigned int multiplier)
 	return -EINVAL;
 }
 
-\f
 static void
 send_ipi_message(const struct cpumask *to_whom, enum ipi_message_type operation)
 {
@@ -552,10 +550,6 @@ handle_ipi(struct pt_regs *regs)
 			generic_smp_call_function_interrupt();
 			break;
 
-		case IPI_CALL_FUNC_SINGLE:
-			generic_smp_call_function_single_interrupt();
-			break;
-
 		case IPI_CPU_STOP:
 			halt();
 
@@ -606,7 +600,7 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
+	send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC);
 }
 
 static void
-- 
1.8.1.2

[RFC PATCH v3 04/19] smp, ARM: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/arm/include/asm/hardirq.h |  2 +-
 arch/arm/kernel/smp.c          | 10 +---------
 2 files changed, 2 insertions(+), 10 deletions(-)

diff --git a/arch/arm/include/asm/hardirq.h b/arch/arm/include/asm/hardirq.h
index fe3ea77..3d7351c 100644
--- a/arch/arm/include/asm/hardirq.h
+++ b/arch/arm/include/asm/hardirq.h
@@ -5,7 +5,7 @@
 #include <linux/threads.h>
 #include <asm/irq.h>
 
-#define NR_IPI	8
+#define NR_IPI	7
 
 typedef struct {
 	unsigned int __softirq_pending;
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index dc894ab..e24a23d 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -65,7 +65,6 @@ enum ipi_msg_type {
 	IPI_TIMER,
 	IPI_RESCHEDULE,
 	IPI_CALL_FUNC,
-	IPI_CALL_FUNC_SINGLE,
 	IPI_CPU_STOP,
 	IPI_IRQ_WORK,
 	IPI_COMPLETION,
@@ -448,7 +447,7 @@ void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
+	smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC);
 }
 
 #ifdef CONFIG_IRQ_WORK
@@ -465,7 +464,6 @@ static const char *ipi_types[NR_IPI] = {
 	S(IPI_TIMER, "Timer broadcast interrupts"),
 	S(IPI_RESCHEDULE, "Rescheduling interrupts"),
 	S(IPI_CALL_FUNC, "Function call interrupts"),
-	S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"),
 	S(IPI_CPU_STOP, "CPU stop interrupts"),
 	S(IPI_IRQ_WORK, "IRQ work interrupts"),
 	S(IPI_COMPLETION, "completion interrupts"),
@@ -579,12 +577,6 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
 		irq_exit();
 		break;
 
-	case IPI_CALL_FUNC_SINGLE:
-		irq_enter();
-		generic_smp_call_function_single_interrupt();
-		irq_exit();
-		break;
-
 	case IPI_CPU_STOP:
 		irq_enter();
 		ipi_cpu_stop(cpu);
-- 
1.8.1.2

[RFC PATCH v3 05/19] smp, ARM64: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/arm64/include/asm/hardirq.h |  2 +-
 arch/arm64/kernel/smp.c          | 10 +---------
 2 files changed, 2 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h
index 990c051..3be64c8 100644
--- a/arch/arm64/include/asm/hardirq.h
+++ b/arch/arm64/include/asm/hardirq.h
@@ -20,7 +20,7 @@
 #include <linux/threads.h>
 #include <asm/irq.h>
 
-#define NR_IPI	4
+#define NR_IPI	3
 
 typedef struct {
 	unsigned int __softirq_pending;
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index a0c2ca6..ea3e9ab 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -59,7 +59,6 @@ struct secondary_data secondary_data;
 enum ipi_msg_type {
 	IPI_RESCHEDULE,
 	IPI_CALL_FUNC,
-	IPI_CALL_FUNC_SINGLE,
 	IPI_CPU_STOP,
 };
 
@@ -438,14 +437,13 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
+	smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC);
 }
 
 static const char *ipi_types[NR_IPI] = {
 #define S(x,s)	[x - IPI_RESCHEDULE] = s
 	S(IPI_RESCHEDULE, "Rescheduling interrupts"),
 	S(IPI_CALL_FUNC, "Function call interrupts"),
-	S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"),
 	S(IPI_CPU_STOP, "CPU stop interrupts"),
 };
 
@@ -520,12 +518,6 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
 		irq_exit();
 		break;
 
-	case IPI_CALL_FUNC_SINGLE:
-		irq_enter();
-		generic_smp_call_function_single_interrupt();
-		irq_exit();
-		break;
-
 	case IPI_CPU_STOP:
 		irq_enter();
 		ipi_cpu_stop(cpu);
-- 
1.8.1.2

[RFC PATCH v3 06/19] smp, blackfin: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: uclinux-dist-devel@blackfin.uclinux.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/blackfin/mach-common/smp.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c
index 2bbae07..ba6c30d 100644
--- a/arch/blackfin/mach-common/smp.c
+++ b/arch/blackfin/mach-common/smp.c
@@ -53,7 +53,6 @@ enum ipi_message_type {
 	BFIN_IPI_TIMER,
 	BFIN_IPI_RESCHEDULE,
 	BFIN_IPI_CALL_FUNC,
-	BFIN_IPI_CALL_FUNC_SINGLE,
 	BFIN_IPI_CPU_STOP,
 };
 
@@ -162,9 +161,6 @@ static irqreturn_t ipi_handler_int1(int irq, void *dev_instance)
 			case BFIN_IPI_CALL_FUNC:
 				generic_smp_call_function_interrupt();
 				break;
-			case BFIN_IPI_CALL_FUNC_SINGLE:
-				generic_smp_call_function_single_interrupt();
-				break;
 			case BFIN_IPI_CPU_STOP:
 				ipi_cpu_stop(cpu);
 				break;
@@ -210,7 +206,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	send_ipi(cpumask_of(cpu), BFIN_IPI_CALL_FUNC_SINGLE);
+	send_ipi(cpumask_of(cpu), BFIN_IPI_CALL_FUNC);
 }
 
 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
-- 
1.8.1.2

[RFC PATCH v3 07/19] smp, hexagon: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-hexagon@vger.kernel.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/hexagon/include/asm/smp.h | 1 -
 arch/hexagon/kernel/smp.c      | 6 +-----
 2 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/arch/hexagon/include/asm/smp.h b/arch/hexagon/include/asm/smp.h
index 2b9b974..ca171c1 100644
--- a/arch/hexagon/include/asm/smp.h
+++ b/arch/hexagon/include/asm/smp.h
@@ -29,7 +29,6 @@ enum ipi_message_type {
 	IPI_NOP = 0,
 	IPI_RESCHEDULE = 1,
 	IPI_CALL_FUNC,
-	IPI_CALL_FUNC_SINGLE,
 	IPI_CPU_STOP,
 	IPI_TIMER,
 };
diff --git a/arch/hexagon/kernel/smp.c b/arch/hexagon/kernel/smp.c
index 9faaa94..ff759f2 100644
--- a/arch/hexagon/kernel/smp.c
+++ b/arch/hexagon/kernel/smp.c
@@ -64,10 +64,6 @@ static inline void __handle_ipi(unsigned long *ops, struct ipi_data *ipi,
 			generic_smp_call_function_interrupt();
 			break;
 
-		case IPI_CALL_FUNC_SINGLE:
-			generic_smp_call_function_single_interrupt();
-			break;
-
 		case IPI_CPU_STOP:
 			/*
 			 * call vmstop()
@@ -248,7 +244,7 @@ void smp_send_stop(void)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	send_ipi(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
+	send_ipi(cpumask_of(cpu), IPI_CALL_FUNC);
 }
 
 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
-- 
1.8.1.2

Re: [RFC PATCH v3 07/19] smp, hexagon: kill SMP single function call interrupt

[rkuo]

On Thu, Dec 05, 2013 at 12:12:58AM +0800, Jiang Liu wrote:
> 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 intterupt
> is needed for architecture specific code to support generic SMP function
> call interfaces, so kill the redundant single function call interrupt.
> 
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Shaohua Li <shli@kernel.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Ingo Molnar <mingo@elte.hu>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Jiri Kosina <trivial@kernel.org>
> Cc: Richard Kuo <rkuo@codeaurora.org>
> Cc: linux-hexagon@vger.kernel.org
> Signed-off-by: Jiang Liu <liuj97@gmail.com>
> ---
>  arch/hexagon/include/asm/smp.h | 1 -
>  arch/hexagon/kernel/smp.c      | 6 +-----
>  2 files changed, 1 insertion(+), 6 deletions(-)

Seems to work fine for Hexagon.  Thanks!


Acked-by: Richard Kuo <rkuo@codeaurora.org>


-- 

Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[RFC PATCH v3 08/19] smp, IA64: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/ia64/kernel/smp.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/ia64/kernel/smp.c b/arch/ia64/kernel/smp.c
index 9fcd4e6..0532909 100644
--- a/arch/ia64/kernel/smp.c
+++ b/arch/ia64/kernel/smp.c
@@ -62,8 +62,7 @@ static DEFINE_PER_CPU_SHARED_ALIGNED(unsigned short [NR_CPUS],
 
 #define IPI_CALL_FUNC		0
 #define IPI_CPU_STOP		1
-#define IPI_CALL_FUNC_SINGLE	2
-#define IPI_KDUMP_CPU_STOP	3
+#define IPI_KDUMP_CPU_STOP	2
 
 /* This needs to be cacheline aligned because it is written to by *other* CPUs.  */
 static DEFINE_PER_CPU_SHARED_ALIGNED(unsigned long, ipi_operation);
@@ -116,9 +115,6 @@ handle_IPI (int irq, void *dev_id)
 			case IPI_CALL_FUNC:
 				generic_smp_call_function_interrupt();
 				break;
-			case IPI_CALL_FUNC_SINGLE:
-				generic_smp_call_function_single_interrupt();
-				break;
 #ifdef CONFIG_KEXEC
 			case IPI_KDUMP_CPU_STOP:
 				unw_init_running(kdump_cpu_freeze, NULL);
@@ -318,7 +314,7 @@ smp_flush_tlb_mm (struct mm_struct *mm)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
+	send_IPI_single(cpu, IPI_CALL_FUNC);
 }
 
 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
-- 
1.8.1.2

[RFC PATCH v3 09/19] smp, m32r: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: linux-m32r@ml.linux-m32r.org
Cc: linux-m32r-ja@ml.linux-m32r.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/m32r/include/asm/smp.h | 1 -
 arch/m32r/kernel/smp.c      | 9 +--------
 arch/m32r/kernel/traps.c    | 3 +--
 3 files changed, 2 insertions(+), 11 deletions(-)

diff --git a/arch/m32r/include/asm/smp.h b/arch/m32r/include/asm/smp.h
index c689b82..3a502d4 100644
--- a/arch/m32r/include/asm/smp.h
+++ b/arch/m32r/include/asm/smp.h
@@ -98,7 +98,6 @@ extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
 #define LOCAL_TIMER_IPI		(M32R_IRQ_IPI3-M32R_IRQ_IPI0)
 #define INVALIDATE_CACHE_IPI	(M32R_IRQ_IPI4-M32R_IRQ_IPI0)
 #define CPU_BOOT_IPI		(M32R_IRQ_IPI5-M32R_IRQ_IPI0)
-#define CALL_FUNC_SINGLE_IPI	(M32R_IRQ_IPI6-M32R_IRQ_IPI0)
 
 #define IPI_SHIFT	(0)
 #define NR_IPIS		(8)
diff --git a/arch/m32r/kernel/smp.c b/arch/m32r/kernel/smp.c
index ce7aea3..c6d0bb9 100644
--- a/arch/m32r/kernel/smp.c
+++ b/arch/m32r/kernel/smp.c
@@ -542,7 +542,7 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	send_IPI_mask(cpumask_of(cpu), CALL_FUNC_SINGLE_IPI, 0);
+	send_IPI_mask(cpumask_of(cpu), CALL_FUNCTION_IPI, 0);
 }
 
 /*==========================================================================*
@@ -569,13 +569,6 @@ void smp_call_function_interrupt(void)
 	irq_exit();
 }
 
-void smp_call_function_single_interrupt(void)
-{
-	irq_enter();
-	generic_smp_call_function_single_interrupt();
-	irq_exit();
-}
-
 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 /* Timer Routines                                                            */
 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
diff --git a/arch/m32r/kernel/traps.c b/arch/m32r/kernel/traps.c
index a7a424f..f5d911d 100644
--- a/arch/m32r/kernel/traps.c
+++ b/arch/m32r/kernel/traps.c
@@ -39,7 +39,6 @@ extern void smp_invalidate_interrupt(void);
 extern void smp_call_function_interrupt(void);
 extern void smp_ipi_timer_interrupt(void);
 extern void smp_flush_cache_all_interrupt(void);
-extern void smp_call_function_single_interrupt(void);
 
 /*
  * for Boot AP function
@@ -104,7 +103,7 @@ static void set_eit_vector_entries(void)
 	eit_vector[187] = (unsigned long)smp_ipi_timer_interrupt;
 	eit_vector[188] = (unsigned long)smp_flush_cache_all_interrupt;
 	eit_vector[189] = 0;	/* CPU_BOOT_IPI */
-	eit_vector[190] = (unsigned long)smp_call_function_single_interrupt;
+	eit_vector[190] = 0;
 	eit_vector[191] = 0;
 #endif
 	_flush_cache_copyback_all();
-- 
1.8.1.2

[RFC PATCH v3 10/19] smp, metag: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/metag/include/asm/smp.h | 2 --
 arch/metag/kernel/smp.c      | 6 +-----
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/metag/include/asm/smp.h b/arch/metag/include/asm/smp.h
index e0373f8..1d7e770 100644
--- a/arch/metag/include/asm/smp.h
+++ b/arch/metag/include/asm/smp.h
@@ -7,13 +7,11 @@
 
 enum ipi_msg_type {
 	IPI_CALL_FUNC,
-	IPI_CALL_FUNC_SINGLE,
 	IPI_RESCHEDULE,
 };
 
 extern void arch_send_call_function_single_ipi(int cpu);
 extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
-#define arch_send_call_function_ipi_mask arch_send_call_function_ipi_mask
 
 asmlinkage void secondary_start_kernel(void);
 
diff --git a/arch/metag/kernel/smp.c b/arch/metag/kernel/smp.c
index 7c01131..5b3933b4 100644
--- a/arch/metag/kernel/smp.c
+++ b/arch/metag/kernel/smp.c
@@ -491,7 +491,7 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
+	send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC);
 }
 
 void show_ipi_list(struct seq_file *p)
@@ -546,10 +546,6 @@ static int do_IPI(struct pt_regs *regs)
 			generic_smp_call_function_interrupt();
 			break;
 
-		case IPI_CALL_FUNC_SINGLE:
-			generic_smp_call_function_single_interrupt();
-			break;
-
 		default:
 			pr_crit("CPU%u: Unknown IPI message 0x%lx\n",
 				cpu, nextmsg);
-- 
1.8.1.2

Re: [RFC PATCH v3 10/19] smp, metag: kill SMP single function call interrupt

[James Hogan]

On 04/12/13 16:13, Jiang Liu wrote:
> 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 intterupt

s/intterupt/interrupt/

> is needed for architecture specific code to support generic SMP function
> call interfaces, so kill the redundant single function call interrupt.
> 
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Shaohua Li <shli@kernel.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Ingo Molnar <mingo@elte.hu>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Jiri Kosina <trivial@kernel.org>
> Cc: James Hogan <james.hogan@imgtec.com>
> Signed-off-by: Jiang Liu <liuj97@gmail.com>

Acked-by: James Hogan <james.hogan@imgtec.com>

Do you want me to take this patch through the metag tree for v3.14 or
let it go via another tree with the other patches?

Thanks
James

Re: [RFC PATCH v3 10/19] smp, metag: kill SMP single function call interrupt

[Jiang Liu]

On 12/05/2013 12:38 AM, James Hogan wrote:
> On 04/12/13 16:13, Jiang Liu wrote:
>> 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 intterupt
> 
> s/intterupt/interrupt/
> 
>> is needed for architecture specific code to support generic SMP function
>> call interfaces, so kill the redundant single function call interrupt.
>>
>> Cc: Andrew Morton <akpm@linux-foundation.org>
>> Cc: Shaohua Li <shli@kernel.org>
>> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
>> Cc: Ingo Molnar <mingo@elte.hu>
>> Cc: Steven Rostedt <rostedt@goodmis.org>
>> Cc: Jiri Kosina <trivial@kernel.org>
>> Cc: James Hogan <james.hogan@imgtec.com>
>> Signed-off-by: Jiang Liu <liuj97@gmail.com>
> 
> Acked-by: James Hogan <james.hogan@imgtec.com>
> 
> Do you want me to take this patch through the metag tree for v3.14 or
> let it go via another tree with the other patches?
Thanks for review. Appreciate if you could help to merge this patch
through metag gate.


> 
> Thanks
> James
> 

[RFC PATCH v3 11/19] smp, mn10300: kill SMP single function call interrupt

[Jiang Liu]

smp, mn10300: rename CALL_FUNC_SINGLE_IPI as CALL_FUNC_IPI

Rename CALL_FUNC_SINGLE_IPI as CALL_FUNC_IPI to prepare for
killing generic_smp_call_function_single_interrupt().

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: linux-am33-list@redhat.com
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/mn10300/include/asm/smp.h |  2 +-
 arch/mn10300/kernel/smp.c      | 16 ++++++++--------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/arch/mn10300/include/asm/smp.h b/arch/mn10300/include/asm/smp.h
index 56c4241..8e689d1 100644
--- a/arch/mn10300/include/asm/smp.h
+++ b/arch/mn10300/include/asm/smp.h
@@ -31,7 +31,7 @@
 #include <proc/smp-regs.h>
 
 #define RESCHEDULE_IPI		63
-#define CALL_FUNC_SINGLE_IPI	192
+#define CALL_FUNC_IPI		192
 #define LOCAL_TIMER_IPI		193
 #define FLUSH_CACHE_IPI		194
 #define CALL_FUNCTION_NMI_IPI	195
diff --git a/arch/mn10300/kernel/smp.c b/arch/mn10300/kernel/smp.c
index a17f9c9..7ae353d 100644
--- a/arch/mn10300/kernel/smp.c
+++ b/arch/mn10300/kernel/smp.c
@@ -164,11 +164,11 @@ static void init_ipi(void)
 	mn10300_ipi_enable(RESCHEDULE_IPI);
 
 	/* set up the call function IPI */
-	irq_set_chip_and_handler(CALL_FUNC_SINGLE_IPI, &mn10300_ipi_type,
+	irq_set_chip_and_handler(CALL_FUNC_IPI, &mn10300_ipi_type,
 				 handle_percpu_irq);
-	setup_irq(CALL_FUNC_SINGLE_IPI, &call_function_ipi);
-	set_intr_level(CALL_FUNC_SINGLE_IPI, CALL_FUNCTION_GxICR_LV);
-	mn10300_ipi_enable(CALL_FUNC_SINGLE_IPI);
+	setup_irq(CALL_FUNC_IPI, &call_function_ipi);
+	set_intr_level(CALL_FUNC_IPI, CALL_FUNCTION_GxICR_LV);
+	mn10300_ipi_enable(CALL_FUNC_IPI);
 
 	/* set up the local timer IPI */
 #if !defined(CONFIG_GENERIC_CLOCKEVENTS) || \
@@ -362,7 +362,7 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	send_IPI_mask(cpumask_of(cpu), CALL_FUNC_SINGLE_IPI);
+	send_IPI_mask(cpumask_of(cpu), CALL_FUNC_IPI);
 }
 
 /**
@@ -519,7 +519,7 @@ static irqreturn_t smp_reschedule_interrupt(int irq, void *dev_id)
 static irqreturn_t smp_call_function_interrupt(int irq, void *dev_id)
 {
 	/* generic_smp_call_function_interrupt(); */
-	generic_smp_call_function_single_interrupt();
+	generic_smp_call_function_interrupt();
 	return IRQ_HANDLED;
 }
 
@@ -598,8 +598,8 @@ static void __init smp_cpu_init(void)
 	/* Force FPU initialization */
 	clear_using_fpu(current);
 
-	GxICR(CALL_FUNC_SINGLE_IPI) = CALL_FUNCTION_GxICR_LV | GxICR_DETECT;
-	mn10300_ipi_enable(CALL_FUNC_SINGLE_IPI);
+	GxICR(CALL_FUNC_IPI) = CALL_FUNCTION_GxICR_LV | GxICR_DETECT;
+	mn10300_ipi_enable(CALL_FUNC_IPI);
 
 	GxICR(LOCAL_TIMER_IPI) = LOCAL_TIMER_GxICR_LV | GxICR_DETECT;
 	mn10300_ipi_enable(LOCAL_TIMER_IPI);
-- 
1.8.1.2

[RFC PATCH v3 12/19] smp, mn10300: enable arch_send_call_function_ipi_mask()

[Jiang Liu]

Enable arch_send_call_function_ipi_mask() on mn10300 to support
smp_call_function_many().

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: linux-am33-list@redhat.com
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/mn10300/kernel/smp.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/mn10300/kernel/smp.c b/arch/mn10300/kernel/smp.c
index 7ae353d..b827b68 100644
--- a/arch/mn10300/kernel/smp.c
+++ b/arch/mn10300/kernel/smp.c
@@ -356,8 +356,7 @@ void send_IPI_allbutself(int irq)
 
 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 {
-	BUG();
-	/*send_IPI_mask(mask, CALL_FUNCTION_IPI);*/
+	send_IPI_mask(mask, CALL_FUNC_IPI);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
-- 
1.8.1.2

[RFC PATCH v3 13/19] smp, s390: prepare for killing generic_smp_call_function_single_interrupt()

[Jiang Liu]

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/s390/kernel/smp.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index dc4a534..e550afd 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -49,7 +49,7 @@
 
 enum {
 	ec_schedule = 0,
-	ec_call_function_single,
+	ec_call_function,
 	ec_stop_cpu,
 };
 
@@ -437,8 +437,8 @@ static void smp_handle_ext_call(void)
 		smp_stop_cpu();
 	if (test_bit(ec_schedule, &bits))
 		scheduler_ipi();
-	if (test_bit(ec_call_function_single, &bits))
-		generic_smp_call_function_single_interrupt();
+	if (test_bit(ec_call_function, &bits))
+		generic_smp_call_function_interrupt();
 }
 
 static void do_ext_call_interrupt(struct ext_code ext_code,
@@ -453,12 +453,12 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 	int cpu;
 
 	for_each_cpu(cpu, mask)
-		pcpu_ec_call(pcpu_devices + cpu, ec_call_function_single);
+		pcpu_ec_call(pcpu_devices + cpu, ec_call_function);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	pcpu_ec_call(pcpu_devices + cpu, ec_call_function_single);
+	pcpu_ec_call(pcpu_devices + cpu, ec_call_function);
 }
 
 #ifndef CONFIG_64BIT
-- 
1.8.1.2

Re: [RFC PATCH v3 13/19] smp, s390: prepare for killing generic_smp_call_function_single_interrupt()

[Heiko Carstens]

On Thu, Dec 05, 2013 at 12:13:04AM +0800, Jiang Liu wrote:
> Signed-off-by: Jiang Liu <liuj97@gmail.com>
> ---
>  arch/s390/kernel/smp.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)

I assume you will take care and make sure it gets merged?
Besides that:

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[RFC PATCH v3 14/19] smp, sh: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/sh/include/asm/smp.h | 1 -
 arch/sh/kernel/smp.c      | 5 +----
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/sh/include/asm/smp.h b/arch/sh/include/asm/smp.h
index 78b0d0f4..93ce87b 100644
--- a/arch/sh/include/asm/smp.h
+++ b/arch/sh/include/asm/smp.h
@@ -25,7 +25,6 @@ extern int __cpu_logical_map[NR_CPUS];
 enum {
 	SMP_MSG_FUNCTION,
 	SMP_MSG_RESCHEDULE,
-	SMP_MSG_FUNCTION_SINGLE,
 	SMP_MSG_TIMER,
 
 	SMP_MSG_NR,	/* must be last */
diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c
index 86a7936..c944d5d 100644
--- a/arch/sh/kernel/smp.c
+++ b/arch/sh/kernel/smp.c
@@ -282,7 +282,7 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	mp_ops->send_ipi(cpu, SMP_MSG_FUNCTION_SINGLE);
+	mp_ops->send_ipi(cpu, SMP_MSG_FUNCTION);
 }
 
 void smp_timer_broadcast(const struct cpumask *mask)
@@ -309,9 +309,6 @@ void smp_message_recv(unsigned int msg)
 	case SMP_MSG_RESCHEDULE:
 		scheduler_ipi();
 		break;
-	case SMP_MSG_FUNCTION_SINGLE:
-		generic_smp_call_function_single_interrupt();
-		break;
 	case SMP_MSG_TIMER:
 		ipi_timer();
 		break;
-- 
1.8.1.2

[RFC PATCH v3 15/19] smp, sparc64: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/sparc/include/asm/pil.h  |  5 ++---
 arch/sparc/kernel/smp_64.c    | 11 +----------
 arch/sparc/kernel/ttable_64.S | 12 ++++--------
 arch/sparc/mm/ultra.S         |  5 -----
 4 files changed, 7 insertions(+), 26 deletions(-)

diff --git a/arch/sparc/include/asm/pil.h b/arch/sparc/include/asm/pil.h
index 2669370..5ffb15d 100644
--- a/arch/sparc/include/asm/pil.h
+++ b/arch/sparc/include/asm/pil.h
@@ -22,9 +22,8 @@
 #define PIL_SMP_CAPTURE		3
 #define PIL_SMP_CTX_NEW_VERSION	4
 #define PIL_DEVICE_IRQ		5
-#define PIL_SMP_CALL_FUNC_SNGL	6
-#define PIL_DEFERRED_PCR_WORK	7
-#define PIL_KGDB_CAPTURE	8
+#define PIL_DEFERRED_PCR_WORK	6
+#define PIL_KGDB_CAPTURE	7
 #define PIL_NORMAL_MAX		14
 #define PIL_NMI			15
 
diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c
index b66a533..07d624b 100644
--- a/arch/sparc/kernel/smp_64.c
+++ b/arch/sparc/kernel/smp_64.c
@@ -811,12 +811,9 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 	xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
 }
 
-extern unsigned long xcall_call_function_single;
-
 void arch_send_call_function_single_ipi(int cpu)
 {
-	xcall_deliver((u64) &xcall_call_function_single, 0, 0,
-		      cpumask_of(cpu));
+	xcall_deliver((u64) &xcall_call_function, 0, 0, cpumask_of(cpu));
 }
 
 void __irq_entry smp_call_function_client(int irq, struct pt_regs *regs)
@@ -825,12 +822,6 @@ void __irq_entry smp_call_function_client(int irq, struct pt_regs *regs)
 	generic_smp_call_function_interrupt();
 }
 
-void __irq_entry smp_call_function_single_client(int irq, struct pt_regs *regs)
-{
-	clear_softint(1 << irq);
-	generic_smp_call_function_single_interrupt();
-}
-
 static void tsb_sync(void *info)
 {
 	struct trap_per_cpu *tp = &trap_block[raw_smp_processor_id()];
diff --git a/arch/sparc/kernel/ttable_64.S b/arch/sparc/kernel/ttable_64.S
index c6dfdaa..defa2db 100644
--- a/arch/sparc/kernel/ttable_64.S
+++ b/arch/sparc/kernel/ttable_64.S
@@ -58,17 +58,13 @@ tl0_irq3:	BTRAP(0x43)
 tl0_irq4:	BTRAP(0x44)
 #endif
 tl0_irq5:	TRAP_IRQ(handler_irq, 5)
-#ifdef CONFIG_SMP
-tl0_irq6:	TRAP_IRQ(smp_call_function_single_client, 6)
-#else
-tl0_irq6:	BTRAP(0x46)
-#endif
-tl0_irq7:	TRAP_IRQ(deferred_pcr_work_irq, 7)
+tl0_irq6:	TRAP_IRQ(deferred_pcr_work_irq, 6)
 #if defined(CONFIG_KGDB) && defined(CONFIG_SMP)
-tl0_irq8:	TRAP_IRQ(smp_kgdb_capture_client, 8)
+tl0_irq7:	TRAP_IRQ(smp_kgdb_capture_client, 7)
 #else
-tl0_irq8:	BTRAP(0x48)
+tl0_irq7:	BTRAP(0x47)
 #endif
+tl0_irq8:	BTRAP(0x48)
 tl0_irq9:	BTRAP(0x49)
 tl0_irq10:	BTRAP(0x4a) BTRAP(0x4b) BTRAP(0x4c) BTRAP(0x4d)
 tl0_irq14:	TRAP_IRQ(timer_interrupt, 14)
diff --git a/arch/sparc/mm/ultra.S b/arch/sparc/mm/ultra.S
index b4f4733..1da4739 100644
--- a/arch/sparc/mm/ultra.S
+++ b/arch/sparc/mm/ultra.S
@@ -780,11 +780,6 @@ xcall_call_function:
 	wr		%g0, (1 << PIL_SMP_CALL_FUNC), %set_softint
 	retry
 
-	.globl		xcall_call_function_single
-xcall_call_function_single:
-	wr		%g0, (1 << PIL_SMP_CALL_FUNC_SNGL), %set_softint
-	retry
-
 	.globl		xcall_receive_signal
 xcall_receive_signal:
 	wr		%g0, (1 << PIL_SMP_RECEIVE_SIGNAL), %set_softint
-- 
1.8.1.2

[RFC PATCH v3 16/19] smp, sparc: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/sparc/include/asm/smp_32.h |  4 +---
 arch/sparc/kernel/entry.S       | 10 ++--------
 arch/sparc/kernel/leon_smp.c    | 31 +++++++------------------------
 arch/sparc/kernel/smp_32.c      | 14 ++------------
 arch/sparc/kernel/sun4d_smp.c   | 31 +++++++------------------------
 arch/sparc/kernel/sun4m_smp.c   | 11 ++---------
 6 files changed, 21 insertions(+), 80 deletions(-)

diff --git a/arch/sparc/include/asm/smp_32.h b/arch/sparc/include/asm/smp_32.h
index 3c8917f..6aec01a 100644
--- a/arch/sparc/include/asm/smp_32.h
+++ b/arch/sparc/include/asm/smp_32.h
@@ -48,7 +48,6 @@ void smp_callin(void);
 void smp_store_cpu_info(int);
 
 void smp_resched_interrupt(void);
-void smp_call_function_single_interrupt(void);
 void smp_call_function_interrupt(void);
 
 struct seq_file;
@@ -60,8 +59,7 @@ struct sparc32_ipi_ops {
 			   unsigned long arg2, unsigned long arg3,
 			   unsigned long arg4);
 	void (*resched)(int cpu);
-	void (*single)(int cpu);
-	void (*mask_one)(int cpu);
+	void (*func_call)(int cpu);
 };
 extern const struct sparc32_ipi_ops *sparc32_ipi_ops;
 
diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S
index 33c02b1..98bacfb 100644
--- a/arch/sparc/kernel/entry.S
+++ b/arch/sparc/kernel/entry.S
@@ -263,7 +263,7 @@ smp4m_ticker:
 	 * on some level other than 15 which is the NMI and only used
 	 * for cross calls.  That has a separate entry point below.
 	 *
-	 * IPIs are sent on Level 12, 13 and 14. See IRQ_IPI_*.
+	 * IPIs are sent on Level 13 and 14. See IRQ_IPI_*.
 	 */
 maybe_smp4m_msg:
 	GET_PROCESSOR4M_ID(o3)
@@ -287,14 +287,8 @@ maybe_smp4m_msg:
 	wr	%l4, PSR_ET, %psr
 	WRITE_PAUSE
 	srl	%o3, 28, %o2		! shift for simpler checks below
-maybe_smp4m_msg_check_single:
-	andcc	%o2, 0x1, %g0
-	beq,a	maybe_smp4m_msg_check_mask
-	 andcc	%o2, 0x2, %g0
-	call	smp_call_function_single_interrupt
-	 nop
-	andcc	%o2, 0x2, %g0
 maybe_smp4m_msg_check_mask:
+	andcc	%o2, 0x2, %g0
 	beq,a	maybe_smp4m_msg_check_resched
 	 andcc	%o2, 0x4, %g0
 	call	smp_call_function_interrupt
diff --git a/arch/sparc/kernel/leon_smp.c b/arch/sparc/kernel/leon_smp.c
index 6edf955..396b71d 100644
--- a/arch/sparc/kernel/leon_smp.c
+++ b/arch/sparc/kernel/leon_smp.c
@@ -271,8 +271,7 @@ void leon_irq_rotate(int cpu)
 }
 
 struct leon_ipi_work {
-	int single;
-	int msk;
+	int func_call;
 	int resched;
 };
 
@@ -308,7 +307,7 @@ static void __init leon_ipi_init(void)
 
 	for_each_possible_cpu(cpu) {
 		work = &per_cpu(leon_ipi_work, cpu);
-		work->single = work->msk = work->resched = 0;
+		work->func_call = work->resched = 0;
 	}
 }
 
@@ -319,23 +318,12 @@ static void leon_send_ipi(int cpu, int level)
 	LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->force[cpu], mask);
 }
 
-static void leon_ipi_single(int cpu)
+static void leon_ipi_func_call(int cpu)
 {
 	struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu);
 
 	/* Mark work */
-	work->single = 1;
-
-	/* Generate IRQ on the CPU */
-	leon_send_ipi(cpu, leon_ipi_irq);
-}
-
-static void leon_ipi_mask_one(int cpu)
-{
-	struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu);
-
-	/* Mark work */
-	work->msk = 1;
+	work->func_call = 1;
 
 	/* Generate IRQ on the CPU */
 	leon_send_ipi(cpu, leon_ipi_irq);
@@ -356,12 +344,8 @@ void leonsmp_ipi_interrupt(void)
 {
 	struct leon_ipi_work *work = &__get_cpu_var(leon_ipi_work);
 
-	if (work->single) {
-		work->single = 0;
-		smp_call_function_single_interrupt();
-	}
-	if (work->msk) {
-		work->msk = 0;
+	if (work->func_call) {
+		work->func_call = 0;
 		smp_call_function_interrupt();
 	}
 	if (work->resched) {
@@ -467,8 +451,7 @@ void leon_cross_call_irq(void)
 static const struct sparc32_ipi_ops leon_ipi_ops = {
 	.cross_call = leon_cross_call,
 	.resched    = leon_ipi_resched,
-	.single     = leon_ipi_single,
-	.mask_one   = leon_ipi_mask_one,
+	.func_call   = leon_ipi_func_call,
 };
 
 void __init leon_init_smp(void)
diff --git a/arch/sparc/kernel/smp_32.c b/arch/sparc/kernel/smp_32.c
index a102bfb..0530d67 100644
--- a/arch/sparc/kernel/smp_32.c
+++ b/arch/sparc/kernel/smp_32.c
@@ -138,17 +138,15 @@ void smp_send_stop(void)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	/* trigger one IPI single call on one CPU */
-	sparc32_ipi_ops->single(cpu);
+	sparc32_ipi_ops->func_call(cpu);
 }
 
 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 {
 	int cpu;
 
-	/* trigger IPI mask call on each CPU */
 	for_each_cpu(cpu, mask)
-		sparc32_ipi_ops->mask_one(cpu);
+		sparc32_ipi_ops->func_call(cpu);
 }
 
 void smp_resched_interrupt(void)
@@ -160,14 +158,6 @@ void smp_resched_interrupt(void)
 	/* re-schedule routine called by interrupt return code. */
 }
 
-void smp_call_function_single_interrupt(void)
-{
-	irq_enter();
-	generic_smp_call_function_single_interrupt();
-	local_cpu_data().irq_call_count++;
-	irq_exit();
-}
-
 void smp_call_function_interrupt(void)
 {
 	irq_enter();
diff --git a/arch/sparc/kernel/sun4d_smp.c b/arch/sparc/kernel/sun4d_smp.c
index d5c3195..72f3797 100644
--- a/arch/sparc/kernel/sun4d_smp.c
+++ b/arch/sparc/kernel/sun4d_smp.c
@@ -181,8 +181,7 @@ void __init smp4d_smp_done(void)
 
 /* Memory structure giving interrupt handler information about IPI generated */
 struct sun4d_ipi_work {
-	int single;
-	int msk;
+	int func_call;
 	int resched;
 };
 
@@ -198,7 +197,7 @@ static void __init smp4d_ipi_init(void)
 
 	for_each_possible_cpu(cpu) {
 		work = &per_cpu(sun4d_ipi_work, cpu);
-		work->single = work->msk = work->resched = 0;
+		work->func_call = work->resched = 0;
 	}
 }
 
@@ -206,12 +205,8 @@ void sun4d_ipi_interrupt(void)
 {
 	struct sun4d_ipi_work *work = &__get_cpu_var(sun4d_ipi_work);
 
-	if (work->single) {
-		work->single = 0;
-		smp_call_function_single_interrupt();
-	}
-	if (work->msk) {
-		work->msk = 0;
+	if (work->func_call) {
+		work->func_call = 0;
 		smp_call_function_interrupt();
 	}
 	if (work->resched) {
@@ -233,23 +228,12 @@ static void sun4d_send_ipi(int cpu, int level)
 	cc_set_igen(IGEN_MESSAGE(0, cpu << 3, 6 + ((level >> 1) & 7), 1 << (level - 1)));
 }
 
-static void sun4d_ipi_single(int cpu)
-{
-	struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
-
-	/* Mark work */
-	work->single = 1;
-
-	/* Generate IRQ on the CPU */
-	sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
-}
-
-static void sun4d_ipi_mask_one(int cpu)
+static void sun4d_ipi_func_call(int cpu)
 {
 	struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
 
 	/* Mark work */
-	work->msk = 1;
+	work->func_call = 1;
 
 	/* Generate IRQ on the CPU */
 	sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
@@ -392,8 +376,7 @@ void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
 static const struct sparc32_ipi_ops sun4d_ipi_ops = {
 	.cross_call = sun4d_cross_call,
 	.resched    = sun4d_ipi_resched,
-	.single     = sun4d_ipi_single,
-	.mask_one   = sun4d_ipi_mask_one,
+	.func_call   = sun4d_ipi_func_call,
 };
 
 void __init sun4d_init_smp(void)
diff --git a/arch/sparc/kernel/sun4m_smp.c b/arch/sparc/kernel/sun4m_smp.c
index d3408e7..d4b7d01 100644
--- a/arch/sparc/kernel/sun4m_smp.c
+++ b/arch/sparc/kernel/sun4m_smp.c
@@ -20,7 +20,6 @@
 #include "irq.h"
 #include "kernel.h"
 
-#define IRQ_IPI_SINGLE		12
 #define IRQ_IPI_MASK		13
 #define IRQ_IPI_RESCHED		14
 #define IRQ_CROSS_CALL		15
@@ -145,12 +144,7 @@ static void sun4m_ipi_resched(int cpu)
 	sun4m_send_ipi(cpu, IRQ_IPI_RESCHED);
 }
 
-static void sun4m_ipi_single(int cpu)
-{
-	sun4m_send_ipi(cpu, IRQ_IPI_SINGLE);
-}
-
-static void sun4m_ipi_mask_one(int cpu)
+static void sun4m_ipi_func_call(int cpu)
 {
 	sun4m_send_ipi(cpu, IRQ_IPI_MASK);
 }
@@ -262,8 +256,7 @@ void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 static const struct sparc32_ipi_ops sun4m_ipi_ops = {
 	.cross_call = sun4m_cross_call,
 	.resched    = sun4m_ipi_resched,
-	.single     = sun4m_ipi_single,
-	.mask_one   = sun4m_ipi_mask_one,
+	.func_call   = sun4m_ipi_func_call,
 };
 
 void __init sun4m_init_smp(void)
-- 
1.8.1.2

[RFC PATCH v3 17/19] smp, tile: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/tile/include/asm/smp.h | 7 +++----
 arch/tile/kernel/smp.c      | 6 +-----
 2 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/tile/include/asm/smp.h b/arch/tile/include/asm/smp.h
index 9a326b6..67e58e7 100644
--- a/arch/tile/include/asm/smp.h
+++ b/arch/tile/include/asm/smp.h
@@ -67,19 +67,18 @@ static inline int xy_to_cpu(int x, int y)
 /* Hypervisor message tags sent via the tile send_IPI*() routines. */
 #define MSG_TAG_START_CPU		1
 #define MSG_TAG_STOP_CPU		2
-#define MSG_TAG_CALL_FUNCTION_MANY	3
-#define MSG_TAG_CALL_FUNCTION_SINGLE	4
+#define MSG_TAG_CALL_FUNCTION		3
 
 /* Hook for the generic smp_call_function_many() routine. */
 static inline void arch_send_call_function_ipi_mask(struct cpumask *mask)
 {
-	send_IPI_many(mask, MSG_TAG_CALL_FUNCTION_MANY);
+	send_IPI_many(mask, MSG_TAG_CALL_FUNCTION);
 }
 
 /* Hook for the generic smp_call_function_single() routine. */
 static inline void arch_send_call_function_single_ipi(int cpu)
 {
-	send_IPI_single(cpu, MSG_TAG_CALL_FUNCTION_SINGLE);
+	send_IPI_single(cpu, MSG_TAG_CALL_FUNCTION);
 }
 
 /* Print out the boot string describing which cpus were disabled. */
diff --git a/arch/tile/kernel/smp.c b/arch/tile/kernel/smp.c
index 01e8ab2..73a1cdc 100644
--- a/arch/tile/kernel/smp.c
+++ b/arch/tile/kernel/smp.c
@@ -139,14 +139,10 @@ void evaluate_message(int tag)
 		smp_stop_cpu_interrupt();
 		break;
 
-	case MSG_TAG_CALL_FUNCTION_MANY: /* Call function on cpumask */
+	case MSG_TAG_CALL_FUNCTION: /* Call function on cpumask */
 		generic_smp_call_function_interrupt();
 		break;
 
-	case MSG_TAG_CALL_FUNCTION_SINGLE: /* Call function on one other CPU */
-		generic_smp_call_function_single_interrupt();
-		break;
-
 	default:
 		panic("Unknown IPI message tag %d", tag);
 		break;
-- 
1.8.1.2

Re: [RFC PATCH v3 17/19] smp, tile: kill SMP single function call interrupt

[Chris Metcalf]

On 12/4/2013 11:13 AM, Jiang Liu wrote:
> 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 intterupt
> is needed for architecture specific code to support generic SMP function
> call interfaces, so kill the redundant single function call interrupt.
>
> Cc: Chris Metcalf <cmetcalf@tilera.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Shaohua Li <shli@kernel.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Ingo Molnar <mingo@elte.hu>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Jiri Kosina <trivial@kernel.org>
> Signed-off-by: Jiang Liu <liuj97@gmail.com>
> ---
>  arch/tile/include/asm/smp.h | 7 +++----
>  arch/tile/kernel/smp.c      | 6 +-----
>  2 files changed, 4 insertions(+), 9 deletions(-)

Acked-by: Chris Metcalf <cmetcalf@tilera.com>

-- 
Chris Metcalf, Tilera Corp.
http://www.tilera.com

[RFC PATCH v3 18/19] smp, tile: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: x86@kernel.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/x86/include/asm/xen/events.h |  1 -
 arch/x86/xen/smp.c                | 38 ++------------------------------------
 2 files changed, 2 insertions(+), 37 deletions(-)

diff --git a/arch/x86/include/asm/xen/events.h b/arch/x86/include/asm/xen/events.h
index 608a79d..a9e54dc 100644
--- a/arch/x86/include/asm/xen/events.h
+++ b/arch/x86/include/asm/xen/events.h
@@ -4,7 +4,6 @@
 enum ipi_vector {
 	XEN_RESCHEDULE_VECTOR,
 	XEN_CALL_FUNCTION_VECTOR,
-	XEN_CALL_FUNCTION_SINGLE_VECTOR,
 	XEN_SPIN_UNLOCK_VECTOR,
 	XEN_IRQ_WORK_VECTOR,
 	XEN_NMI_VECTOR,
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index c36b325..7cf1689 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -46,12 +46,10 @@ struct xen_common_irq {
 };
 static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 };
 static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
-static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
 static DEFINE_PER_CPU(struct xen_common_irq, xen_irq_work) = { .irq = -1 };
 static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };
 
 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
-static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id);
 
 /*
@@ -123,13 +121,6 @@ static void xen_smp_intr_free(unsigned int cpu)
 		kfree(per_cpu(xen_debug_irq, cpu).name);
 		per_cpu(xen_debug_irq, cpu).name = NULL;
 	}
-	if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) {
-		unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq,
-				       NULL);
-		per_cpu(xen_callfuncsingle_irq, cpu).irq = -1;
-		kfree(per_cpu(xen_callfuncsingle_irq, cpu).name);
-		per_cpu(xen_callfuncsingle_irq, cpu).name = NULL;
-	}
 	if (xen_hvm_domain())
 		return;
 
@@ -178,18 +169,6 @@ static int xen_smp_intr_init(unsigned int cpu)
 	per_cpu(xen_debug_irq, cpu).irq = rc;
 	per_cpu(xen_debug_irq, cpu).name = debug_name;
 
-	callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
-	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
-				    cpu,
-				    xen_call_function_single_interrupt,
-				    IRQF_PERCPU|IRQF_NOBALANCING,
-				    callfunc_name,
-				    NULL);
-	if (rc < 0)
-		goto fail;
-	per_cpu(xen_callfuncsingle_irq, cpu).irq = rc;
-	per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name;
-
 	/*
 	 * The IRQ worker on PVHVM goes through the native path and uses the
 	 * IPI mechanism.
@@ -569,8 +548,7 @@ static void xen_smp_send_call_function_ipi(const struct cpumask *mask)
 
 static void xen_smp_send_call_function_single_ipi(int cpu)
 {
-	__xen_send_IPI_mask(cpumask_of(cpu),
-			  XEN_CALL_FUNCTION_SINGLE_VECTOR);
+	__xen_send_IPI_mask(cpumask_of(cpu), XEN_CALL_FUNCTION_VECTOR);
 }
 
 static inline int xen_map_vector(int vector)
@@ -582,10 +560,8 @@ static inline int xen_map_vector(int vector)
 		xen_vector = XEN_RESCHEDULE_VECTOR;
 		break;
 	case CALL_FUNCTION_VECTOR:
-		xen_vector = XEN_CALL_FUNCTION_VECTOR;
-		break;
 	case CALL_FUNCTION_SINGLE_VECTOR:
-		xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
+		xen_vector = XEN_CALL_FUNCTION_VECTOR;
 		break;
 	case IRQ_WORK_VECTOR:
 		xen_vector = XEN_IRQ_WORK_VECTOR;
@@ -663,16 +639,6 @@ static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
-{
-	irq_enter();
-	generic_smp_call_function_single_interrupt();
-	inc_irq_stat(irq_call_count);
-	irq_exit();
-
-	return IRQ_HANDLED;
-}
-
 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id)
 {
 	irq_enter();
-- 
1.8.1.2

[RFC PATCH v3 19/19] smp, x86: kill SMP single function call interrupt

[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 intterupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: x86@kernel.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Jiang Liu <liuj97@gmail.com>
---
 arch/x86/include/asm/entry_arch.h        |  1 -
 arch/x86/include/asm/hw_irq.h            |  3 ---
 arch/x86/include/asm/irq_vectors.h       |  7 +++----
 arch/x86/include/asm/trace/irq_vectors.h |  6 ------
 arch/x86/kernel/entry_64.S               |  2 --
 arch/x86/kernel/irqinit.c                |  4 ----
 arch/x86/kernel/smp.c                    | 24 +-----------------------
 arch/x86/xen/smp.c                       |  1 -
 8 files changed, 4 insertions(+), 44 deletions(-)

diff --git a/arch/x86/include/asm/entry_arch.h b/arch/x86/include/asm/entry_arch.h
index dc5fa66..9670cff 100644
--- a/arch/x86/include/asm/entry_arch.h
+++ b/arch/x86/include/asm/entry_arch.h
@@ -12,7 +12,6 @@
 #ifdef CONFIG_SMP
 BUILD_INTERRUPT(reschedule_interrupt,RESCHEDULE_VECTOR)
 BUILD_INTERRUPT(call_function_interrupt,CALL_FUNCTION_VECTOR)
-BUILD_INTERRUPT(call_function_single_interrupt,CALL_FUNCTION_SINGLE_VECTOR)
 BUILD_INTERRUPT3(irq_move_cleanup_interrupt, IRQ_MOVE_CLEANUP_VECTOR,
 		 smp_irq_move_cleanup_interrupt)
 BUILD_INTERRUPT3(reboot_interrupt, REBOOT_VECTOR, smp_reboot_interrupt)
diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index cba45d9..66bacec 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -75,7 +75,6 @@ extern asmlinkage void reboot_interrupt(void);
 extern asmlinkage void threshold_interrupt(void);
 
 extern asmlinkage void call_function_interrupt(void);
-extern asmlinkage void call_function_single_interrupt(void);
 
 #ifdef CONFIG_TRACING
 /* Interrupt handlers registered during init_IRQ */
@@ -88,7 +87,6 @@ extern void trace_thermal_interrupt(void);
 extern void trace_reschedule_interrupt(void);
 extern void trace_threshold_interrupt(void);
 extern void trace_call_function_interrupt(void);
-extern void trace_call_function_single_interrupt(void);
 #define trace_irq_move_cleanup_interrupt  irq_move_cleanup_interrupt
 #define trace_reboot_interrupt  reboot_interrupt
 #define trace_kvm_posted_intr_ipi kvm_posted_intr_ipi
@@ -182,7 +180,6 @@ extern asmlinkage void smp_irq_move_cleanup_interrupt(void);
 #ifdef CONFIG_SMP
 extern __visible void smp_reschedule_interrupt(struct pt_regs *);
 extern __visible void smp_call_function_interrupt(struct pt_regs *);
-extern __visible void smp_call_function_single_interrupt(struct pt_regs *);
 extern __visible void smp_invalidate_interrupt(struct pt_regs *);
 #endif
 
diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index 5702d7e..98a302d 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -92,10 +92,9 @@
 #define ERROR_APIC_VECTOR		0xfe
 #define RESCHEDULE_VECTOR		0xfd
 #define CALL_FUNCTION_VECTOR		0xfc
-#define CALL_FUNCTION_SINGLE_VECTOR	0xfb
-#define THERMAL_APIC_VECTOR		0xfa
-#define THRESHOLD_APIC_VECTOR		0xf9
-#define REBOOT_VECTOR			0xf8
+#define THERMAL_APIC_VECTOR		0xfb
+#define THRESHOLD_APIC_VECTOR		0xfa
+#define REBOOT_VECTOR			0xf9
 
 /*
  * Generic system vector for platform specific use
diff --git a/arch/x86/include/asm/trace/irq_vectors.h b/arch/x86/include/asm/trace/irq_vectors.h
index 4cab890..e672e20 100644
--- a/arch/x86/include/asm/trace/irq_vectors.h
+++ b/arch/x86/include/asm/trace/irq_vectors.h
@@ -89,12 +89,6 @@ TRACE_EVENT_PERF_PERM(irq_work_exit, is_sampling_event(p_event) ? -EPERM : 0);
 DEFINE_IRQ_VECTOR_EVENT(call_function);
 
 /*
- * call_function_single - called when entering/exiting a call function
- * single interrupt vector handler
- */
-DEFINE_IRQ_VECTOR_EVENT(call_function_single);
-
-/*
  * threshold_apic - called when entering/exiting a threshold apic interrupt
  * vector handler
  */
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index e21b078..8d5d21a 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1182,8 +1182,6 @@ apicinterrupt THERMAL_APIC_VECTOR \
 #endif
 
 #ifdef CONFIG_SMP
-apicinterrupt CALL_FUNCTION_SINGLE_VECTOR \
-	call_function_single_interrupt smp_call_function_single_interrupt
 apicinterrupt CALL_FUNCTION_VECTOR \
 	call_function_interrupt smp_call_function_interrupt
 apicinterrupt RESCHEDULE_VECTOR \
diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c
index a2a1fbc..4aa1b8c 100644
--- a/arch/x86/kernel/irqinit.c
+++ b/arch/x86/kernel/irqinit.c
@@ -141,10 +141,6 @@ static void __init smp_intr_init(void)
 	/* IPI for generic function call */
 	alloc_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
 
-	/* IPI for generic single function call */
-	alloc_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
-			call_function_single_interrupt);
-
 	/* Low priority IPI to cleanup after moving an irq */
 	set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
 	set_bit(IRQ_MOVE_CLEANUP_VECTOR, used_vectors);
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 7c3a5a6..f363dd2 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -129,7 +129,7 @@ static void native_smp_send_reschedule(int cpu)
 
 void native_send_call_func_single_ipi(int cpu)
 {
-	apic->send_IPI_mask(cpumask_of(cpu), CALL_FUNCTION_SINGLE_VECTOR);
+	apic->send_IPI_mask(cpumask_of(cpu), CALL_FUNCTION_VECTOR);
 }
 
 void native_send_call_func_ipi(const struct cpumask *mask)
@@ -311,28 +311,6 @@ __visible void smp_trace_call_function_interrupt(struct pt_regs *regs)
 	exiting_irq();
 }
 
-static inline void __smp_call_function_single_interrupt(void)
-{
-	generic_smp_call_function_single_interrupt();
-	inc_irq_stat(irq_call_count);
-}
-
-__visible void smp_call_function_single_interrupt(struct pt_regs *regs)
-{
-	smp_entering_irq();
-	__smp_call_function_single_interrupt();
-	exiting_irq();
-}
-
-__visible void smp_trace_call_function_single_interrupt(struct pt_regs *regs)
-{
-	smp_entering_irq();
-	trace_call_function_single_entry(CALL_FUNCTION_SINGLE_VECTOR);
-	__smp_call_function_single_interrupt();
-	trace_call_function_single_exit(CALL_FUNCTION_SINGLE_VECTOR);
-	exiting_irq();
-}
-
 static int __init nonmi_ipi_setup(char *str)
 {
 	smp_no_nmi_ipi = true;
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 7cf1689..f241792 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -560,7 +560,6 @@ static inline int xen_map_vector(int vector)
 		xen_vector = XEN_RESCHEDULE_VECTOR;
 		break;
 	case CALL_FUNCTION_VECTOR:
-	case CALL_FUNCTION_SINGLE_VECTOR:
 		xen_vector = XEN_CALL_FUNCTION_VECTOR;
 		break;
 	case IRQ_WORK_VECTOR:
-- 
1.8.1.2

Re: [RFC PATCH v3 00/19] simplify generic cross CPU function call implementation

[Christoph Hellwig]

On Thu, Dec 05, 2013 at 12:12:51AM +0800, Jiang Liu wrote:
> Since commit 9a46ad6d6df3b54 "smp: make smp_call_function_many() use
> logic similar to smp_call_function_single()", single and multiple
> (mask version) cross CPU function calls are handled in the same way,
> and generic_smp_call_function_interrupt() becomes an aliases of
> generic_smp_call_function_single_interrupt(), so only one interrupt
> is needed for arch code to support generic SMP function call interfaces.
> This patch series simplifies arch code by killing the redundant
> interrupt for cross CPU function calls.
> 
> We choose to keep generic_smp_call_function_interrupt() instead of
> generic_smp_call_function_single_interrupt() because the former is
> more generic.

Maybe drop the generic as well to get the name down to a reasonable
length? :)