Re: [RFC PATCH 4/9] irq_work: Let the arch tell us about self-IPI support

2012-10-29 Thread Frederic Weisbecker
2012/10/29 Steven Rostedt :
> On Mon, 2012-10-29 at 14:28 +0100, Frederic Weisbecker wrote:
>> This prepares us to make printk working on nohz CPUs
>> using irq work.
>
> -ENOTENOUGHINFO
>
> Please state how this prepares printk for nohz CPUS using irq_work.

RIght, I'll add the details in the next version.
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Re: [RFC PATCH 4/9] irq_work: Let the arch tell us about self-IPI support

2012-10-29 Thread Steven Rostedt
On Mon, 2012-10-29 at 14:28 +0100, Frederic Weisbecker wrote:
> This prepares us to make printk working on nohz CPUs
> using irq work.

-ENOTENOUGHINFO

Please state how this prepares printk for nohz CPUS using irq_work.

Thanks,

-- Steve

> 
> Signed-off-by: Frederic Weisbecker 
> Cc: Peter Zijlstra 
> Cc: Thomas Gleixner 
> Cc: Ingo Molnar 
> Cc: Andrew Morton 
> Cc: Steven Rostedt 
> Cc: Paul Gortmaker 
> ---


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[RFC PATCH 4/9] irq_work: Let the arch tell us about self-IPI support

2012-10-29 Thread Frederic Weisbecker
This prepares us to make printk working on nohz CPUs
using irq work.

Signed-off-by: Frederic Weisbecker 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Andrew Morton 
Cc: Steven Rostedt 
Cc: Paul Gortmaker 
---
 arch/alpha/include/asm/irq_work.h   |5 -
 arch/alpha/kernel/time.c|2 +-
 arch/powerpc/include/asm/irq_work.h |4 +++-
 arch/powerpc/kernel/time.c  |2 +-
 arch/sparc/include/asm/irq_work.h   |4 +++-
 arch/sparc/kernel/pcr.c |2 +-
 arch/x86/include/asm/irq_work.h |9 +
 arch/x86/kernel/irq_work.c  |2 +-
 include/asm-generic/irq_work.h  |   14 ++
 9 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/arch/alpha/include/asm/irq_work.h 
b/arch/alpha/include/asm/irq_work.h
index 814ff3d..3d32132 100644
--- a/arch/alpha/include/asm/irq_work.h
+++ b/arch/alpha/include/asm/irq_work.h
@@ -1,6 +1,9 @@
 #ifndef _ALPHA_IRQ_WORK_H
 #define _ALPHA_IRQ_WORK_H
 
-extern void arch_irq_work_raise(void);
+extern void __arch_irq_work_raise(void);
+#define arch_irq_work_raise __arch_irq_work_raise
+
+#include 
 
 #endif
diff --git a/arch/alpha/kernel/time.c b/arch/alpha/kernel/time.c
index e336694..91c5eec 100644
--- a/arch/alpha/kernel/time.c
+++ b/arch/alpha/kernel/time.c
@@ -90,7 +90,7 @@ DEFINE_PER_CPU(u8, irq_work_pending);
 #define test_irq_work_pending()  __get_cpu_var(irq_work_pending)
 #define clear_irq_work_pending() __get_cpu_var(irq_work_pending) = 0
 
-void arch_irq_work_raise(void)
+void __arch_irq_work_raise(void)
 {
set_irq_work_pending_flag();
 }
diff --git a/arch/powerpc/include/asm/irq_work.h 
b/arch/powerpc/include/asm/irq_work.h
index 8b9927f..8aa36aa 100644
--- a/arch/powerpc/include/asm/irq_work.h
+++ b/arch/powerpc/include/asm/irq_work.h
@@ -1,6 +1,8 @@
 #ifndef _ASM_POWERPC_IRQ_WORK_H
 #define _ASM_POWERPC_IRQ_WORK_H
 
-extern void arch_irq_work_raise(void);
+extern void __arch_irq_work_raise(void);
+#define arch_irq_work_raise __arch_irq_work_raise
 
+#include 
 #endif
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index c9986fd..31565ac 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -466,7 +466,7 @@ DEFINE_PER_CPU(u8, irq_work_pending);
 
 #endif /* 32 vs 64 bit */
 
-void arch_irq_work_raise(void)
+void __arch_irq_work_raise(void)
 {
preempt_disable();
set_irq_work_pending_flag();
diff --git a/arch/sparc/include/asm/irq_work.h 
b/arch/sparc/include/asm/irq_work.h
index 1d062a6..383772d 100644
--- a/arch/sparc/include/asm/irq_work.h
+++ b/arch/sparc/include/asm/irq_work.h
@@ -1,6 +1,8 @@
 #ifndef ___ASM_SPARC_IRQ_H
 #define ___ASM_SPARC_IRQ_H
 
-extern void arch_irq_work_raise(void);
+extern void __arch_irq_work_raise(void);
+#define arch_irq_work_raise __arch_irq_work_raise
 
+#include 
 #endif
diff --git a/arch/sparc/kernel/pcr.c b/arch/sparc/kernel/pcr.c
index 269af58..d1e1ecf 100644
--- a/arch/sparc/kernel/pcr.c
+++ b/arch/sparc/kernel/pcr.c
@@ -43,7 +43,7 @@ void __irq_entry deferred_pcr_work_irq(int irq, struct 
pt_regs *regs)
set_irq_regs(old_regs);
 }
 
-void arch_irq_work_raise(void)
+void __arch_irq_work_raise(void)
 {
set_softint(1 << PIL_DEFERRED_PCR_WORK);
 }
diff --git a/arch/x86/include/asm/irq_work.h b/arch/x86/include/asm/irq_work.h
index 38eed96..dad8266 100644
--- a/arch/x86/include/asm/irq_work.h
+++ b/arch/x86/include/asm/irq_work.h
@@ -1,10 +1,11 @@
 #ifndef _ASM_X86_IRQ_WORK_H
 #define _ASM_X86_IRQ_WORK_H
 
-#ifndef CONFIG_X86_LOCAL_APIC
-#include 
-# else
-extern void arch_irq_work_raise(void);
+#ifdef CONFIG_X86_LOCAL_APIC
+extern void __arch_irq_work_raise(void);
+#define arch_irq_work_raise __arch_irq_work_raise
 #endif
 
+#include 
+
 #endif
diff --git a/arch/x86/kernel/irq_work.c b/arch/x86/kernel/irq_work.c
index 95f5d4e..7389d5e 100644
--- a/arch/x86/kernel/irq_work.c
+++ b/arch/x86/kernel/irq_work.c
@@ -19,7 +19,7 @@ void smp_irq_work_interrupt(struct pt_regs *regs)
 }
 
 #ifdef CONFIG_X86_LOCAL_APIC
-void arch_irq_work_raise(void)
+void __arch_irq_work_raise(void)
 {
if (!cpu_has_apic)
return;
diff --git a/include/asm-generic/irq_work.h b/include/asm-generic/irq_work.h
index a2d4108..e3e4f02 100644
--- a/include/asm-generic/irq_work.h
+++ b/include/asm-generic/irq_work.h
@@ -4,6 +4,20 @@
 /*
  * Lame architectures will get the timer tick callback
  */
+#ifndef arch_irq_work_raise
 static inline void arch_irq_work_raise(void) { }
+#endif
+
+/*
+ * Unless told otherwise, consider the arch doesn't implement irq work
+ * using self IPIs but through another way like defaulting to the hook
+ * on the sched tick.
+ */
+#ifndef arch_irq_work_has_ipi
+static inline bool arch_irq_work_has_ipi(void)
+{
+   return false;
+}
+#endif
 
 #endif
-- 
1.7.5.4

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