sparc64: Make %pil level 15 a pseudo-NMI.

So that we can profile code even in a local_irq_disable() section,
only write 14 (instead of 15) into the %pil register to disable IRQs.

This allows PIL level 15 to serve as a pseudo NMI.

Signed-off-by: David S. Miller <davem@davemloft.net>

12 files changed, 46 insertions, 25 deletions

diff --git a/arch/sparc/include/asm/irqflags_64.h b/arch/sparc/include/asm/irqflags_64.h
index bb42e59162a..8b49bf920df 100644
--- a/arch/sparc/include/asm/irqflags_64.h
+++ b/arch/sparc/include/asm/irqflags_64.h
@@ -10,6 +10,8 @@
 #ifndef _ASM_IRQFLAGS_H
 #define _ASM_IRQFLAGS_H
 
+#include <asm/pil.h>
+
 #ifndef __ASSEMBLY__
 
 static inline unsigned long __raw_local_save_flags(void)
@@ -40,9 +42,9 @@ static inline void raw_local_irq_restore(unsigned long flags)
 static inline void raw_local_irq_disable(void)
 {
 	__asm__ __volatile__(
-		"wrpr	15, %%pil"
+		"wrpr	%0, %%pil"
 		: /* no outputs */
-		: /* no inputs */
+		: "i" (PIL_NORMAL_MAX)
 		: "memory"
 	);
 }
diff --git a/arch/sparc/include/asm/pil.h b/arch/sparc/include/asm/pil.h
index 71819bb943f..d573820c0ff 100644
--- a/arch/sparc/include/asm/pil.h
+++ b/arch/sparc/include/asm/pil.h
@@ -10,7 +10,12 @@
  *
  * In fact any XCALL which has to etrap/rtrap has a problem because
  * it is difficult to prevent rtrap from running BH's, and that would
- * need to be done if the XCALL arrived while %pil==15.
+ * need to be done if the XCALL arrived while %pil==PIL_NORMAL_MAX.
+ *
+ * Finally, in order to handle profiling events even when a
+ * local_irq_disable() is in progress, we only disable up to level 14
+ * interrupts.  Profile counter overflow interrupts arrive at level
+ * 15.
  */
 #define PIL_SMP_CALL_FUNC	1
 #define PIL_SMP_RECEIVE_SIGNAL	2
@@ -18,5 +23,7 @@
 #define PIL_SMP_CTX_NEW_VERSION	4
 #define PIL_DEVICE_IRQ		5
 #define PIL_SMP_CALL_FUNC_SNGL	6
+#define PIL_NORMAL_MAX		14
+#define PIL_NMI			15
 
 #endif /* !(_SPARC64_PIL_H) */
diff --git a/arch/sparc/include/asm/ttable.h b/arch/sparc/include/asm/ttable.h
index 5708ba2719f..bb2c0770a6a 100644
--- a/arch/sparc/include/asm/ttable.h
+++ b/arch/sparc/include/asm/ttable.h
@@ -2,6 +2,7 @@
 #define _SPARC64_TTABLE_H
 
 #include <asm/utrap.h>
+#include <asm/pil.h>
 
 #ifdef __ASSEMBLY__
 #include <asm/thread_info.h>
@@ -123,7 +124,7 @@
 
 #define TRAP_IRQ(routine, level)			\
 	rdpr	%pil, %g2;				\
-	wrpr	%g0, 15, %pil;				\
+	wrpr	%g0, PIL_NORMAL_MAX, %pil;		\
 	sethi	%hi(1f-4), %g7;				\
 	ba,pt	%xcc, etrap_irq;			\
 	 or	%g7, %lo(1f-4), %g7;			\
@@ -143,7 +144,7 @@
 
 #define TRAP_IRQ(routine, level)			\
 	rdpr	%pil, %g2;				\
-	wrpr	%g0, 15, %pil;				\
+	wrpr	%g0, PIL_NORMAL_MAX, %pil;		\
 	ba,pt	%xcc, etrap_irq;			\
 	 rd	%pc, %g7;				\
 	mov	level, %o0;				\
@@ -153,6 +154,16 @@
 
 #endif
 
+#define TRAP_NMI_IRQ(routine, level)			\
+	rdpr	%pil, %g2;				\
+	wrpr	%g0, PIL_NMI, %pil;			\
+	ba,pt	%xcc, etrap_irq;			\
+	 rd	%pc, %g7;				\
+	mov	level, %o0;				\
+	call	routine;				\
+	 add	%sp, PTREGS_OFF, %o1;			\
+	ba,a,pt	%xcc, rtrap_irq;
+
 #define TRAP_IVEC TRAP_NOSAVE(do_ivec)
 
 #define BTRAP(lvl) TRAP_ARG(bad_trap, lvl)
diff --git a/arch/sparc/mm/ultra.S b/arch/sparc/mm/ultra.S
index e4c146f7c7e..80c788ec7c3 100644
--- a/arch/sparc/mm/ultra.S
+++ b/arch/sparc/mm/ultra.S
@@ -466,7 +466,7 @@ xcall_sync_tick:
 	.previous
 
 	rdpr		%pil, %g2
-	wrpr		%g0, 15, %pil
+	wrpr		%g0, PIL_NORMAL_MAX, %pil
 	sethi		%hi(109f), %g7
 	b,pt		%xcc, etrap_irq
 109:	 or		%g7, %lo(109b), %g7
@@ -688,7 +688,7 @@ xcall_kgdb_capture:
 	.previous
 
 	rdpr		%pil, %g2
-	wrpr		%g0, 15, %pil
+	wrpr		%g0, PIL_NORMAL_MAX, %pil
 	sethi		%hi(109f), %g7
 	ba,pt		%xcc, etrap_irq
 109:	 or		%g7, %lo(109b), %g7
diff --git a/arch/sparc64/kernel/cherrs.S b/arch/sparc64/kernel/cherrs.S
index 89afebd7eca..4ee1ad42086 100644
--- a/arch/sparc64/kernel/cherrs.S
+++ b/arch/sparc64/kernel/cherrs.S
@@ -102,7 +102,7 @@ cheetah_plus_dcpe_trap_vector:
 	.type		do_cheetah_plus_data_parity,#function
 do_cheetah_plus_data_parity:
 	rdpr		%pil, %g2
-	wrpr		%g0, 15, %pil
+	wrpr		%g0, PIL_NORMAL_MAX, %pil
 	ba,pt		%xcc, etrap_irq
 	 rd		%pc, %g7
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -144,7 +144,7 @@ cheetah_plus_icpe_trap_vector:
 	.type		do_cheetah_plus_insn_parity,#function
 do_cheetah_plus_insn_parity:
 	rdpr		%pil, %g2
-	wrpr		%g0, 15, %pil
+	wrpr		%g0, PIL_NORMAL_MAX, %pil
 	ba,pt		%xcc, etrap_irq
 	 rd		%pc, %g7
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -492,7 +492,7 @@ cheetah_fast_ecc:
 	.type		c_fast_ecc,#function
 c_fast_ecc:
 	rdpr		%pil, %g2
-	wrpr		%g0, 15, %pil
+	wrpr		%g0, PIL_NORMAL_MAX, %pil
 	ba,pt		%xcc, etrap_irq
 	 rd		%pc, %g7
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -528,7 +528,7 @@ cheetah_cee:
 	.type		c_cee,#function
 c_cee:
 	rdpr		%pil, %g2
-	wrpr		%g0, 15, %pil
+	wrpr		%g0, PIL_NORMAL_MAX, %pil
 	ba,pt		%xcc, etrap_irq
 	 rd		%pc, %g7
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -564,7 +564,7 @@ cheetah_deferred_trap:
 	.type		c_deferred,#function
 c_deferred:
 	rdpr		%pil, %g2
-	wrpr		%g0, 15, %pil
+	wrpr		%g0, PIL_NORMAL_MAX, %pil
 	ba,pt		%xcc, etrap_irq
 	 rd		%pc, %g7
 #ifdef CONFIG_TRACE_IRQFLAGS
diff --git a/arch/sparc64/kernel/head.S b/arch/sparc64/kernel/head.S
index 353226fa023..45830c35fc6 100644
--- a/arch/sparc64/kernel/head.S
+++ b/arch/sparc64/kernel/head.S
@@ -706,7 +706,7 @@ setup_trap_table:
 	andn	%l0, PSTATE_IE, %o1
 	wrpr	%o1, 0x0, %pstate
 	rdpr	%pil, %l1
-	wrpr	%g0, 15, %pil
+	wrpr	%g0, PIL_NORMAL_MAX, %pil
 
 	/* Make the firmware call to jump over to the Linux trap table.  */
 	sethi	%hi(is_sun4v), %o0
diff --git a/arch/sparc64/kernel/hvtramp.S b/arch/sparc64/kernel/hvtramp.S
index 0236c43772f..9365432904d 100644
--- a/arch/sparc64/kernel/hvtramp.S
+++ b/arch/sparc64/kernel/hvtramp.S
@@ -1,6 +1,6 @@
 /* hvtramp.S: Hypervisor start-cpu trampoline code.
  *
- * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
+ * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
  */
 
 #include <linux/init.h>
@@ -14,6 +14,7 @@
 #include <asm/ptrace.h>
 #include <asm/head.h>
 #include <asm/asi.h>
+#include <asm/pil.h>
 
 	__CPUINIT
 	.align		8
@@ -32,7 +33,7 @@
 	 */
 hv_cpu_startup:
 	SET_GL(0)
-	wrpr		%g0, 15, %pil
+	wrpr		%g0, PIL_NORMAL_MAX, %pil
 	wrpr		%g0, 0, %canrestore
 	wrpr		%g0, 0, %otherwin
 	wrpr		%g0, 6, %cansave
diff --git a/arch/sparc64/kernel/smp.c b/arch/sparc64/kernel/smp.c
index c6d06362728..b5225c81556 100644
--- a/arch/sparc64/kernel/smp.c
+++ b/arch/sparc64/kernel/smp.c
@@ -1146,8 +1146,8 @@ void smp_release(void)
 	}
 }
 
-/* Imprisoned penguins run with %pil == 15, but PSTATE_IE set, so they
- * can service tlb flush xcalls...
+/* Imprisoned penguins run with %pil == PIL_NORMAL_MAX, but PSTATE_IE
+ * set, so they can service tlb flush xcalls...
  */
 extern void prom_world(int);
 
diff --git a/arch/sparc64/kernel/spiterrs.S b/arch/sparc64/kernel/spiterrs.S
index ef902c6f8e3..c357e40ffd0 100644
--- a/arch/sparc64/kernel/spiterrs.S
+++ b/arch/sparc64/kernel/spiterrs.S
@@ -80,7 +80,7 @@ __spitfire_cee_trap_continue:
 	cmp		%g2, 1
 	rdpr		%pil, %g2
 	bleu,pt		%xcc, 1f
-	 wrpr		%g0, 15, %pil
+	 wrpr		%g0, PIL_NORMAL_MAX, %pil
 
 	ba,pt		%xcc, etraptl1
 	 rd		%pc, %g7
diff --git a/arch/sparc64/kernel/sun4v_ivec.S b/arch/sparc64/kernel/sun4v_ivec.S
index e2f8e1b4882..559bc5e9c19 100644
--- a/arch/sparc64/kernel/sun4v_ivec.S
+++ b/arch/sparc64/kernel/sun4v_ivec.S
@@ -186,7 +186,7 @@ sun4v_res_mondo:
 	 * when it's done.
 	 */
 	rdpr	%pil, %g2
-	wrpr	%g0, 15, %pil
+	wrpr	%g0, PIL_NORMAL_MAX, %pil
 	mov	%g1, %g4
 	ba,pt	%xcc, etrap_irq
 	 rd	%pc, %g7
@@ -216,7 +216,7 @@ sun4v_res_mondo_queue_full:
 	membar	#Sync
 
 	rdpr	%pil, %g2
-	wrpr	%g0, 15, %pil
+	wrpr	%g0, PIL_NORMAL_MAX, %pil
 	ba,pt	%xcc, etrap_irq
 	 rd	%pc, %g7
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -297,7 +297,7 @@ sun4v_nonres_mondo:
 	 * when it's done.
 	 */
 	rdpr	%pil, %g2
-	wrpr	%g0, 15, %pil
+	wrpr	%g0, PIL_NORMAL_MAX, %pil
 	mov	%g1, %g4
 	ba,pt	%xcc, etrap_irq
 	 rd	%pc, %g7
@@ -327,7 +327,7 @@ sun4v_nonres_mondo_queue_full:
 	membar	#Sync
 
 	rdpr	%pil, %g2
-	wrpr	%g0, 15, %pil
+	wrpr	%g0, PIL_NORMAL_MAX, %pil
 	ba,pt	%xcc, etrap_irq
 	 rd	%pc, %g7
 #ifdef CONFIG_TRACE_IRQFLAGS
diff --git a/arch/sparc64/kernel/traps.c b/arch/sparc64/kernel/traps.c
index 04994fc8700..4638af2f55a 100644
--- a/arch/sparc64/kernel/traps.c
+++ b/arch/sparc64/kernel/traps.c
@@ -1832,7 +1832,7 @@ static void sun4v_log_error(struct pt_regs *regs, struct sun4v_error_entry *ent,
 	}
 }
 
-/* We run with %pil set to 15 and PSTATE_IE enabled in %pstate.
+/* We run with %pil set to PIL_NORMAL_MAX and PSTATE_IE enabled in %pstate.
  * Log the event and clear the first word of the entry.
  */
 void sun4v_resum_error(struct pt_regs *regs, unsigned long offset)
@@ -1880,7 +1880,7 @@ void sun4v_resum_overflow(struct pt_regs *regs)
 	atomic_inc(&sun4v_resum_oflow_cnt);
 }
 
-/* We run with %pil set to 15 and PSTATE_IE enabled in %pstate.
+/* We run with %pil set to PIL_NORMAL_MAX and PSTATE_IE enabled in %pstate.
  * Log the event, clear the first word of the entry, and die.
  */
 void sun4v_nonresum_error(struct pt_regs *regs, unsigned long offset)
diff --git a/arch/sparc64/kernel/ttable.S b/arch/sparc64/kernel/ttable.S
index 2a31ffa4c28..ea925503b42 100644
--- a/arch/sparc64/kernel/ttable.S
+++ b/arch/sparc64/kernel/ttable.S
@@ -66,7 +66,7 @@ tl0_irq6:	BTRAP(0x46)
 tl0_irq7:	BTRAP(0x47) BTRAP(0x48) BTRAP(0x49)
 tl0_irq10:	BTRAP(0x4a) BTRAP(0x4b) BTRAP(0x4c) BTRAP(0x4d)
 tl0_irq14:	TRAP_IRQ(timer_interrupt, 14)
-tl0_irq15:	TRAP_IRQ(perfctr_irq, 15)
+tl0_irq15:	TRAP_NMI_IRQ(perfctr_irq, 15)
 tl0_resv050:	BTRAP(0x50) BTRAP(0x51) BTRAP(0x52) BTRAP(0x53) BTRAP(0x54) BTRAP(0x55)
 tl0_resv056:	BTRAP(0x56) BTRAP(0x57) BTRAP(0x58) BTRAP(0x59) BTRAP(0x5a) BTRAP(0x5b)
 tl0_resv05c:	BTRAP(0x5c) BTRAP(0x5d) BTRAP(0x5e) BTRAP(0x5f)