sh: stacktrace/lockdep/irqflags tracing support.

Wire up all of the essentials for lockdep..

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

11 files changed, 289 insertions, 103 deletions

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index aa1ebc561b84..013732074d35 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -51,6 +51,14 @@ config GENERIC_TIME
 config ARCH_MAY_HAVE_PC_FDC
 	bool
 
+config STACKTRACE_SUPPORT
+	bool
+	default y
+
+config LOCKDEP_SUPPORT
+	bool
+	default y
+
 source "init/Kconfig"
 
 menu "System type"
diff --git a/arch/sh/Kconfig.debug b/arch/sh/Kconfig.debug
index dcceec95a2d5..66a25ef4ef1b 100644
--- a/arch/sh/Kconfig.debug
+++ b/arch/sh/Kconfig.debug
@@ -1,5 +1,9 @@
 menu "Kernel hacking"
 
+config TRACE_IRQFLAGS_SUPPORT
+	bool
+	default y
+
 source "lib/Kconfig.debug"
 
 config SH_STANDARD_BIOS
diff --git a/arch/sh/kernel/Makefile b/arch/sh/kernel/Makefile
index 50d54c24d76a..99c7e5249f7a 100644
--- a/arch/sh/kernel/Makefile
+++ b/arch/sh/kernel/Makefile
@@ -21,3 +21,4 @@ obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
 obj-$(CONFIG_KEXEC)		+= machine_kexec.o relocate_kernel.o
 obj-$(CONFIG_APM)		+= apm.o
 obj-$(CONFIG_PM)		+= pm.o
+obj-$(CONFIG_STACKTRACE)	+= stacktrace.o
diff --git a/arch/sh/kernel/cpu/sh2/entry.S b/arch/sh/kernel/cpu/sh2/entry.S
index 298d9191909d..34d51b3745ea 100644
--- a/arch/sh/kernel/cpu/sh2/entry.S
+++ b/arch/sh/kernel/cpu/sh2/entry.S
@@ -184,6 +184,11 @@ trap_entry:
 	add	r15,r8
 	mov.l	r9,@r8
 	mov	r9,r8
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	5f, r9
+	jsr	@r9
+	 nop
+#endif
 	sti
 	bra	system_call
 	 nop
@@ -193,6 +198,9 @@ trap_entry:
 2:	.long	break_point_trap_software
 3:	.long	NR_syscalls
 4:	.long	sys_call_table
+#ifdef CONFIG_TRACE_IRQFLAGS
+5:	.long	trace_hardirqs_on
+#endif
 
 #if defined(CONFIG_SH_STANDARD_BIOS)
 	/* Unwind the stack and jmp to the debug entry */
@@ -255,6 +263,11 @@ ENTRY(address_error_handler)
 
 restore_all:
 	cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	3f, r0
+	jsr	@r0
+	 nop
+#endif
 	mov	r15,r0
 	mov.l	$cpu_mode,r2
 	mov	#OFF_SR,r3
@@ -307,6 +320,9 @@ $current_thread_info:
 	.long	__current_thread_info
 $cpu_mode:	
 	.long	__cpu_mode
+#ifdef CONFIG_TRACE_IRQFLAGS
+3:	.long	trace_hardirqs_off
+#endif
 		
 ! common exception handler
 #include "../../entry-common.S"
diff --git a/arch/sh/kernel/cpu/sh3/entry.S b/arch/sh/kernel/cpu/sh3/entry.S
index 7ba3dcbe7504..8c0dc2700c69 100644
--- a/arch/sh/kernel/cpu/sh3/entry.S
+++ b/arch/sh/kernel/cpu/sh3/entry.S
@@ -140,7 +140,7 @@ call_dpf:
 	mov.l	1f, r0
  	mov.l	@r0, r6		! address
 	mov.l	3f, r0
-	sti
+
 	jmp	@r0
  	 mov	r15, r4		! regs
 
diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S
index 8f96d21fcb1c..29136a35d7c7 100644
--- a/arch/sh/kernel/entry-common.S
+++ b/arch/sh/kernel/entry-common.S
@@ -100,6 +100,11 @@ debug_trap:
 	.align	2
 ENTRY(exception_error)
 	!
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	3f, r0
+	jsr	@r0
+	 nop
+#endif
 	sti
 	mov.l	2f, r0
 	jmp	@r0
@@ -109,10 +114,18 @@ ENTRY(exception_error)
 	.align	2
 1:	.long	break_point_trap_software
 2:	.long	do_exception_error
+#ifdef CONFIG_TRACE_IRQFLAGS
+3:	.long	trace_hardirqs_on
+#endif
 
 	.align	2
 ret_from_exception:
 	preempt_stop()
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	4f, r0
+	jsr	@r0
+	 nop
+#endif
 ENTRY(ret_from_irq)
 	!
 	mov	#OFF_SR, r0
@@ -143,6 +156,11 @@ need_resched:
 	mov.l	1f, r0
 	mov.l	r0, @(TI_PRE_COUNT,r8)
 
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	3f, r0
+	jsr	@r0
+	 nop
+#endif
 	sti
 	mov.l	2f, r0
 	jsr	@r0
@@ -150,9 +168,15 @@ need_resched:
 	mov	#0, r0
 	mov.l	r0, @(TI_PRE_COUNT,r8)
 	cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	4f, r0
+	jsr	@r0
+	 nop
+#endif
 
 	bra	need_resched
 	 nop
+
 noresched:
 	bra	__restore_all
 	 nop
@@ -160,11 +184,20 @@ noresched:
 	.align 2
 1:	.long	PREEMPT_ACTIVE
 2:	.long	schedule
+#ifdef CONFIG_TRACE_IRQFLAGS
+3:	.long	trace_hardirqs_on
+4:	.long	trace_hardirqs_off
+#endif
 #endif
 
 ENTRY(resume_userspace)
 	! r8: current_thread_info
 	cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	5f, r0
+	jsr	@r0
+	 nop
+#endif
 	mov.l	@(TI_FLAGS,r8), r0		! current_thread_info->flags
 	tst	#_TIF_WORK_MASK, r0
 	bt/s	__restore_all
@@ -210,6 +243,11 @@ work_resched:
 	jsr	@r1				! schedule
 	 nop
 	cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	5f, r0
+	jsr	@r0
+	 nop
+#endif
 	!
 	mov.l	@(TI_FLAGS,r8), r0		! current_thread_info->flags
 	tst	#_TIF_WORK_MASK, r0
@@ -221,6 +259,10 @@ work_resched:
 1:	.long	schedule
 2:	.long	do_notify_resume
 3:	.long	restore_all
+#ifdef CONFIG_TRACE_IRQFLAGS
+4:	.long	trace_hardirqs_on
+5:	.long	trace_hardirqs_off
+#endif
 
 	.align	2
 syscall_exit_work:
@@ -229,6 +271,11 @@ syscall_exit_work:
 	tst	#_TIF_SYSCALL_TRACE, r0
 	bt/s	work_pending
 	 tst	#_TIF_NEED_RESCHED, r0
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	5f, r0
+	jsr	@r0
+	 nop
+#endif
 	sti
 	! XXX setup arguments...
 	mov.l	4f, r0			! do_syscall_trace
@@ -265,7 +312,7 @@ syscall_trace_entry:
 	 mov.l	r0, @(OFF_R0,r15)	! Return value
 
 __restore_all:
-	mov.l	1f,r0
+	mov.l	1f, r0
 	jmp	@r0
 	 nop
 
@@ -331,7 +378,13 @@ ENTRY(system_call)
 	 mov	#OFF_TRA, r9
 	add	r15, r9
 	mov.l	r8, @r9			! set TRA value to tra
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	5f, r10
+	jsr	@r10
+	 nop
+#endif
 	sti
+
 	!
 	get_current_thread_info r8, r10
 	mov.l	@(TI_FLAGS,r8), r8
@@ -355,6 +408,11 @@ syscall_call:
 	!
 syscall_exit:
 	cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mov.l	6f, r0
+	jsr	@r0
+	 nop
+#endif
 	!
 	get_current_thread_info r8, r0
 	mov.l	@(TI_FLAGS,r8), r0		! current_thread_info->flags
@@ -369,3 +427,7 @@ syscall_exit:
 2:	.long	NR_syscalls
 3:	.long	sys_call_table
 4:	.long	do_syscall_trace
+#ifdef CONFIG_TRACE_IRQFLAGS
+5:	.long	trace_hardirqs_on
+6:	.long	trace_hardirqs_off
+#endif
diff --git a/arch/sh/kernel/stacktrace.c b/arch/sh/kernel/stacktrace.c
new file mode 100644
index 000000000000..0d5268afe80f
--- /dev/null
+++ b/arch/sh/kernel/stacktrace.c
@@ -0,0 +1,43 @@
+/*
+ * arch/sh/kernel/stacktrace.c
+ *
+ * Stack trace management functions
+ *
+ *  Copyright (C) 2006  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <linux/thread_info.h>
+#include <asm/ptrace.h>
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer.
+ */
+void save_stack_trace(struct stack_trace *trace, struct task_struct *task)
+{
+	unsigned long *sp;
+
+	if (!task)
+		task = current;
+	if (task == current)
+		sp = (unsigned long *)current_stack_pointer;
+	else
+		sp = (unsigned long *)task->thread.sp;
+
+	while (!kstack_end(sp)) {
+		unsigned long addr = *sp++;
+
+		if (__kernel_text_address(addr)) {
+			if (trace->skip > 0)
+				trace->skip--;
+			else
+				trace->entries[trace->nr_entries++] = addr;
+			if (trace->nr_entries >= trace->max_entries)
+				break;
+		}
+	}
+}
diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
index cfeefc10e254..716ebf568af2 100644
--- a/arch/sh/mm/fault.c
+++ b/arch/sh/mm/fault.c
@@ -37,6 +37,9 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
 	int si_code;
 	siginfo_t info;
 
+	trace_hardirqs_on();
+	local_irq_enable();
+
 #ifdef CONFIG_SH_KGDB
 	if (kgdb_nofault && kgdb_bus_err_hook)
 		kgdb_bus_err_hook();
diff --git a/include/asm-sh/irqflags.h b/include/asm-sh/irqflags.h
new file mode 100644
index 000000000000..9dedc1b693e3
--- /dev/null
+++ b/include/asm-sh/irqflags.h
@@ -0,0 +1,123 @@
+#ifndef __ASM_SH_IRQFLAGS_H
+#define __ASM_SH_IRQFLAGS_H
+
+static inline void raw_local_irq_enable(void)
+{
+	unsigned long __dummy0, __dummy1;
+
+	__asm__ __volatile__ (
+		"stc	sr, %0\n\t"
+		"and	%1, %0\n\t"
+#ifdef CONFIG_CPU_HAS_SR_RB
+		"stc	r6_bank, %1\n\t"
+		"or	%1, %0\n\t"
+#endif
+		"ldc	%0, sr\n\t"
+		: "=&r" (__dummy0), "=r" (__dummy1)
+		: "1" (~0x000000f0)
+		: "memory"
+	);
+}
+
+static inline void raw_local_irq_disable(void)
+{
+	unsigned long flags;
+
+	__asm__ __volatile__ (
+		"stc	sr, %0\n\t"
+		"or	#0xf0, %0\n\t"
+		"ldc	%0, sr\n\t"
+		: "=&z" (flags)
+		: /* no inputs */
+		: "memory"
+	);
+}
+
+static inline void set_bl_bit(void)
+{
+	unsigned long __dummy0, __dummy1;
+
+	__asm__ __volatile__ (
+		"stc	sr, %0\n\t"
+		"or	%2, %0\n\t"
+		"and	%3, %0\n\t"
+		"ldc	%0, sr\n\t"
+		: "=&r" (__dummy0), "=r" (__dummy1)
+		: "r" (0x10000000), "r" (0xffffff0f)
+		: "memory"
+	);
+}
+
+static inline void clear_bl_bit(void)
+{
+	unsigned long __dummy0, __dummy1;
+
+	__asm__ __volatile__ (
+		"stc	sr, %0\n\t"
+		"and	%2, %0\n\t"
+		"ldc	%0, sr\n\t"
+		: "=&r" (__dummy0), "=r" (__dummy1)
+		: "1" (~0x10000000)
+		: "memory"
+	);
+}
+
+static inline unsigned long __raw_local_save_flags(void)
+{
+	unsigned long flags;
+
+	__asm__ __volatile__ (
+		"stc	sr, %0\n\t"
+		"and	#0xf0, %0\n\t"
+		: "=&z" (flags)
+		: /* no inputs */
+		: "memory"
+	);
+
+	return flags;
+}
+
+#define raw_local_save_flags(flags) \
+		do { (flags) = __raw_local_save_flags(); } while (0)
+
+static inline int raw_irqs_disabled_flags(unsigned long flags)
+{
+	return (flags != 0);
+}
+
+static inline int raw_irqs_disabled(void)
+{
+	unsigned long flags = __raw_local_save_flags();
+
+	return raw_irqs_disabled_flags(flags);
+}
+
+static inline unsigned long __raw_local_irq_save(void)
+{
+	unsigned long flags, __dummy;
+
+	__asm__ __volatile__ (
+		"stc	sr, %1\n\t"
+		"mov	%1, %0\n\t"
+		"or	#0xf0, %0\n\t"
+		"ldc	%0, sr\n\t"
+		"mov	%1, %0\n\t"
+		"and	#0xf0, %0\n\t"
+		: "=&z" (flags), "=&r" (__dummy)
+		: /* no inputs */
+		: "memory"
+	);
+
+	return flags;
+}
+
+#define raw_local_irq_save(flags) \
+		do { (flags) = __raw_local_irq_save(); } while (0)
+
+static inline void raw_local_irq_restore(unsigned long flags)
+{
+	if ((flags & 0xf0) != 0xf0)
+		raw_local_irq_enable();
+}
+
+#endif /* __ASM_SH_IRQFLAGS_H */
diff --git a/include/asm-sh/rwsem.h b/include/asm-sh/rwsem.h
index 9d2aea5e8488..4931ba817d73 100644
--- a/include/asm-sh/rwsem.h
+++ b/include/asm-sh/rwsem.h
@@ -25,11 +25,21 @@ struct rw_semaphore {
 #define RWSEM_ACTIVE_WRITE_BIAS		(RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS)
 	spinlock_t		wait_lock;
 	struct list_head	wait_list;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map	dep_map;
+#endif
 };
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __RWSEM_DEP_MAP_INIT(lockname) , .dep_map = { .name = #lockname }
+#else
+# define __RWSEM_DEP_MAP_INIT(lockname)
+#endif
+
 #define __RWSEM_INITIALIZER(name) \
 	{ RWSEM_UNLOCKED_VALUE, SPIN_LOCK_UNLOCKED, \
-	  LIST_HEAD_INIT((name).wait_list) }
+	  LIST_HEAD_INIT((name).wait_list) \
+	  __RWSEM_DEP_MAP_INIT(name) }
 
 #define DECLARE_RWSEM(name)		\
 	struct rw_semaphore name = __RWSEM_INITIALIZER(name)
@@ -39,6 +49,16 @@ extern struct rw_semaphore *rwsem_down_write_failed(struct rw_semaphore *sem);
 extern struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem);
 extern struct rw_semaphore *rwsem_downgrade_wake(struct rw_semaphore *sem);
 
+extern void __init_rwsem(struct rw_semaphore *sem, const char *name,
+			 struct lock_class_key *key);
+
+#define init_rwsem(sem)				\
+do {						\
+	static struct lock_class_key __key;	\
+						\
+	__init_rwsem((sem), #sem, &__key);	\
+} while (0)
+
 static inline void init_rwsem(struct rw_semaphore *sem)
 {
 	sem->count = RWSEM_UNLOCKED_VALUE;
@@ -141,6 +161,11 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
 		rwsem_downgrade_wake(sem);
 }
 
+static inline void __down_write_nested(struct rw_semaphore *sem, int subclass)
+{
+	__down_write(sem);
+}
+
 /*
  * implement exchange and add functionality
  */
diff --git a/include/asm-sh/system.h b/include/asm-sh/system.h
index 3340126f4e0f..b1e42e7f998b 100644
--- a/include/asm-sh/system.h
+++ b/include/asm-sh/system.h
@@ -6,6 +6,7 @@
  * Copyright (C) 2002 Paul Mundt
  */
 
+#include <linux/irqflags.h>
 #include <asm/types.h>
 
 /*
@@ -131,103 +132,6 @@ static inline unsigned long tas(volatile int *m)
 
 #define set_mb(var, value) do { xchg(&var, value); } while (0)
 
-/* Interrupt Control */
-#ifdef CONFIG_CPU_HAS_SR_RB
-static inline void local_irq_enable(void)
-{
-	unsigned long __dummy0, __dummy1;
-
-	__asm__ __volatile__("stc	sr, %0\n\t"
-			     "and	%1, %0\n\t"
-			     "stc	r6_bank, %1\n\t"
-			     "or	%1, %0\n\t"
-			     "ldc	%0, sr"
-			     : "=&r" (__dummy0), "=r" (__dummy1)
-			     : "1" (~0x000000f0)
-			     : "memory");
-}
-#else
-static inline void local_irq_enable(void)
-{
-	unsigned long __dummy0, __dummy1;
-
-	__asm__ __volatile__ (
-		"stc	sr, %0\n\t"
-		"and	%1, %0\n\t"
-		"ldc	%0, sr\n\t"
-		: "=&r" (__dummy0), "=r" (__dummy1)
-		: "1" (~0x000000f0)
-		: "memory");
-}
-#endif
-
-static inline void local_irq_disable(void)
-{
-	unsigned long __dummy;
-	__asm__ __volatile__("stc	sr, %0\n\t"
-			     "or	#0xf0, %0\n\t"
-			     "ldc	%0, sr"
-			     : "=&z" (__dummy)
-			     : /* no inputs */
-			     : "memory");
-}
-
-static inline void set_bl_bit(void)
-{
-	unsigned long __dummy0, __dummy1;
-
-	__asm__ __volatile__ ("stc	sr, %0\n\t"
-			     "or	%2, %0\n\t"
-			     "and	%3, %0\n\t"
-			     "ldc	%0, sr"
-			     : "=&r" (__dummy0), "=r" (__dummy1)
-			     : "r" (0x10000000), "r" (0xffffff0f)
-			     : "memory");
-}
-
-static inline void clear_bl_bit(void)
-{
-	unsigned long __dummy0, __dummy1;
-
-	__asm__ __volatile__ ("stc	sr, %0\n\t"
-			     "and	%2, %0\n\t"
-			     "ldc	%0, sr"
-			     : "=&r" (__dummy0), "=r" (__dummy1)
-			     : "1" (~0x10000000)
-			     : "memory");
-}
-
-#define local_save_flags(x) \
-	__asm__("stc sr, %0; and #0xf0, %0" : "=&z" (x) :/**/: "memory" )
-
-#define irqs_disabled()			\
-({					\
-	unsigned long flags;		\
-	local_save_flags(flags);	\
-	(flags != 0);			\
-})
-
-static inline unsigned long local_irq_save(void)
-{
-	unsigned long flags, __dummy;
-
-	__asm__ __volatile__("stc	sr, %1\n\t"
-			     "mov	%1, %0\n\t"
-			     "or	#0xf0, %0\n\t"
-			     "ldc	%0, sr\n\t"
-			     "mov	%1, %0\n\t"
-			     "and	#0xf0, %0"
-			     : "=&z" (flags), "=&r" (__dummy)
-			     :/**/
-			     : "memory" );
-	return flags;
-}
-
-#define local_irq_restore(x) do {			\
-	if ((x & 0x000000f0) != 0x000000f0)		\
-		local_irq_enable();			\
-} while (0)
-
 /*
  * Jump to P2 area.
  * When handling TLB or caches, we need to do it from P2 area.
@@ -264,9 +168,6 @@ do {							\
 		: "=&r" (__dummy));			\
 } while (0)
 
-/* For spinlocks etc */
-#define local_irq_save(x)	x = local_irq_save()
-
 static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
 {
 	unsigned long flags, retval;