Linux Virtualization - Apr 2008 - [PATCH 0/3] ia64/pv_ops preparation

Hi. This patchset is preparation patches for ia64/pv_ops support.
They are almost trivial and mainly make kernel paravirtualization friendly.

thanks,

Diffstat:
 arch/ia64/kernel/irq_ia64.c    |    1 -
 include/asm-ia64/intrinsics.h  |   11 +++++++++++
 include/asm-ia64/mmu_context.h |    6 +-----
 include/asm-ia64/smp.h         |    2 ++
 include/asm-ia64/system.h      |   10 ++++++++--
 5 files changed, 22 insertions(+), 8 deletions(-)

remove extern declaration of handle_IPI() in irq_ia64.c.
Instead, declare it in asm-ia64/smp.h.
Later handle_IPI() will be referenced from another file.

Signed-off-by: Isaku Yamahata <yamahata at valinux.co.jp>
---
 arch/ia64/kernel/irq_ia64.c |    1 -
 include/asm-ia64/smp.h      |    2 ++
 2 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/arch/ia64/kernel/irq_ia64.c b/arch/ia64/kernel/irq_ia64.c
index 5538471..c48171b 100644
--- a/arch/ia64/kernel/irq_ia64.c
+++ b/arch/ia64/kernel/irq_ia64.c
@@ -600,7 +600,6 @@ static irqreturn_t dummy_handler (int irq, void *dev_id)
 {
 	BUG();
 }
-extern irqreturn_t handle_IPI (int irq, void *dev_id);
 
 static struct irqaction ipi_irqaction = {
 	.handler =	handle_IPI,
diff --git a/include/asm-ia64/smp.h b/include/asm-ia64/smp.h
index ec5f355..2984e26 100644
--- a/include/asm-ia64/smp.h
+++ b/include/asm-ia64/smp.h
@@ -15,6 +15,7 @@
 #include <linux/kernel.h>
 #include <linux/cpumask.h>
 #include <linux/bitops.h>
+#include <linux/irqreturn.h>
 
 #include <asm/io.h>
 #include <asm/param.h>
@@ -123,6 +124,7 @@ extern void __init smp_build_cpu_map(void);
 extern void __init init_smp_config (void);
 extern void smp_do_timer (struct pt_regs *regs);
 
+extern irqreturn_t handle_IPI(int irq, void *dev_id);
 extern void smp_send_reschedule (int cpu);
 extern void lock_ipi_calllock(void);
 extern void unlock_ipi_calllock(void);
-- 
1.5.3

make kernel paravirtualization friendly by introducing
ia64_set_rr0_to_rr4().
ia64/Xen will replace setting rr[0-4] with single hypercall later.

Signed-off-by: Isaku Yamahata <yamahata at valinux.co.jp>
---
 include/asm-ia64/intrinsics.h  |    9 +++++++++
 include/asm-ia64/mmu_context.h |    6 +-----
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/include/asm-ia64/intrinsics.h b/include/asm-ia64/intrinsics.h
index f1135b5..9b83f8f 100644
--- a/include/asm-ia64/intrinsics.h
+++ b/include/asm-ia64/intrinsics.h
@@ -18,6 +18,15 @@
 # include <asm/gcc_intrin.h>
 #endif
 
+#define ia64_set_rr0_to_rr4(val0, val1, val2, val3, val4)	\
+do {								\
+	ia64_set_rr(0x0000000000000000UL, (val0));		\
+	ia64_set_rr(0x2000000000000000UL, (val1));		\
+	ia64_set_rr(0x4000000000000000UL, (val2));		\
+	ia64_set_rr(0x6000000000000000UL, (val3));		\
+	ia64_set_rr(0x8000000000000000UL, (val4));		\
+} while (0)
+
 /*
  * Force an unresolved reference if someone tries to use
  * ia64_fetch_and_add() with a bad value.
diff --git a/include/asm-ia64/mmu_context.h b/include/asm-ia64/mmu_context.h
index cef2400..040bc87 100644
--- a/include/asm-ia64/mmu_context.h
+++ b/include/asm-ia64/mmu_context.h
@@ -152,11 +152,7 @@ reload_context (nv_mm_context_t context)
 #  endif
 #endif
 
-	ia64_set_rr(0x0000000000000000UL, rr0);
-	ia64_set_rr(0x2000000000000000UL, rr1);
-	ia64_set_rr(0x4000000000000000UL, rr2);
-	ia64_set_rr(0x6000000000000000UL, rr3);
-	ia64_set_rr(0x8000000000000000UL, rr4);
+	ia64_set_rr0_to_rr4(rr0, rr1, rr2, rr3, rr4);
 	ia64_srlz_i();			/* srlz.i implies srlz.d */
 }
 
-- 
1.5.3

__local_irq_save() and local_save_flags() are used to mask interruptions.
They read all psr bits that requres whole bit emulation.
On the other hand, reading only psr.i, the single bit, can be virtualized
cheaply.

Signed-off-by: Isaku Yamahata <yamahata at valinux.co.jp>
---
 include/asm-ia64/intrinsics.h |    2 ++
 include/asm-ia64/system.h     |   10 ++++++++--
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/include/asm-ia64/intrinsics.h b/include/asm-ia64/intrinsics.h
index 9b83f8f..a3b9689 100644
--- a/include/asm-ia64/intrinsics.h
+++ b/include/asm-ia64/intrinsics.h
@@ -18,6 +18,8 @@
 # include <asm/gcc_intrin.h>
 #endif
 
+#define ia64_get_psr_i()	(ia64_getreg(_IA64_REG_PSR) & IA64_PSR_I)
+
 #define ia64_set_rr0_to_rr4(val0, val1, val2, val3, val4)	\
 do {								\
 	ia64_set_rr(0x0000000000000000UL, (val0));		\
diff --git a/include/asm-ia64/system.h b/include/asm-ia64/system.h
index dff8128..bcc2483 100644
--- a/include/asm-ia64/system.h
+++ b/include/asm-ia64/system.h
@@ -122,10 +122,16 @@ extern struct ia64_boot_param {
  *   write a floating-point register right before reading the PSR
  *   and that writes to PSR.mfl
  */
+#ifdef CONFIG_PARAVIRT
+#define __local_save_flags()	ia64_get_psr_i()
+#else
+#define __local_save_flags()	ia64_getreg(_IA64_REG_PSR)
+#endif
+
 #define __local_irq_save(x)			\
 do {						\
 	ia64_stop();				\
-	(x) = ia64_getreg(_IA64_REG_PSR);	\
+	(x) = __local_save_flags();		\
 	ia64_stop();				\
 	ia64_rsm(IA64_PSR_I);			\
 } while (0)
@@ -173,7 +179,7 @@ do {								\
 #endif /* !CONFIG_IA64_DEBUG_IRQ */
 
 #define local_irq_enable()	({ ia64_stop(); ia64_ssm(IA64_PSR_I); ia64_srlz_d();
})
-#define local_save_flags(flags)	({ ia64_stop(); (flags) =
ia64_getreg(_IA64_REG_PSR); })
+#define local_save_flags(flags)	({ ia64_stop(); (flags) = __local_save_flags();
})
 
 #define irqs_disabled()				\
 ({						\
-- 
1.5.3