[PATCH] lockdep: irqtrace subsystem, i386 support

Add irqflags-tracing support to i386.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 62 insertions, 19 deletions

diff --git a/include/asm-i386/irqflags.h b/include/asm-i386/irqflags.h
new file mode 100644
index 000000000000..ca777e894c92
--- /dev/null
+++ b/include/asm-i386/irqflags.h
@@ -0,0 +1,56 @@
+/*
+ * include/asm-i386/irqflags.h
+ *
+ * IRQ flags handling
+ *
+ * This file gets included from lowlevel asm headers too, to provide
+ * wrapped versions of the local_irq_*() APIs, based on the
+ * raw_local_irq_*() macros from the lowlevel headers.
+ */
+#ifndef _ASM_IRQFLAGS_H
+#define _ASM_IRQFLAGS_H
+
+#define raw_local_save_flags(x) do { typecheck(unsigned long,x); __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */); } while (0)
+#define raw_local_irq_restore(x) do { typecheck(unsigned long,x); __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory", "cc"); } while (0)
+#define raw_local_irq_disable() __asm__ __volatile__("cli": : :"memory")
+#define raw_local_irq_enable()  __asm__ __volatile__("sti": : :"memory")
+/* used in the idle loop; sti takes one instruction cycle to complete */
+#define raw_safe_halt()         __asm__ __volatile__("sti; hlt": : :"memory")
+/* used when interrupts are already enabled or to shutdown the processor */
+#define halt()                  __asm__ __volatile__("hlt": : :"memory")
+
+#define raw_irqs_disabled_flags(flags)  (!((flags) & (1<<9)))
+
+/* For spinlocks etc */
+#define raw_local_irq_save(x)   __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory")
+
+/*
+ * Do the CPU's IRQ-state tracing from assembly code. We call a
+ * C function, so save all the C-clobbered registers:
+ */
+#ifdef CONFIG_TRACE_IRQFLAGS
+
+# define TRACE_IRQS_ON                          \
+        pushl %eax;                             \
+        pushl %ecx;                             \
+        pushl %edx;                             \
+        call trace_hardirqs_on;                 \
+        popl %edx;                              \
+        popl %ecx;                              \
+        popl %eax;
+
+# define TRACE_IRQS_OFF                         \
+        pushl %eax;                             \
+        pushl %ecx;                             \
+        pushl %edx;                             \
+        call trace_hardirqs_off;                \
+        popl %edx;                              \
+        popl %ecx;                              \
+        popl %eax;
+
+#else
+# define TRACE_IRQS_ON
+# define TRACE_IRQS_OFF
+#endif
+
+#endif
diff --git a/include/asm-i386/spinlock.h b/include/asm-i386/spinlock.h
index 04ba30234c48..7e29b51bcaa0 100644
--- a/include/asm-i386/spinlock.h
+++ b/include/asm-i386/spinlock.h
@@ -31,6 +31,11 @@
         "jmp 1b\n" \
         "3:\n\t"
 
+/*
+ * NOTE: there's an irqs-on section here, which normally would have to be
+ * irq-traced, but on CONFIG_TRACE_IRQFLAGS we never use
+ * __raw_spin_lock_string_flags().
+ */
 #define __raw_spin_lock_string_flags \
         "\n1:\t" \
         "lock ; decb %0\n\t" \
diff --git a/include/asm-i386/system.h b/include/asm-i386/system.h
index cab0180567f9..db398d88b1d9 100644
--- a/include/asm-i386/system.h
+++ b/include/asm-i386/system.h
@@ -456,25 +456,7 @@ static inline unsigned long long __cmpxchg64(volatile void *ptr, unsigned long l
 
 #define set_wmb(var, value) do { var = value; wmb(); } while (0)
 
-/* interrupt control.. */
-#define local_save_flags(x)     do { typecheck(unsigned long,x); __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */); } while (0)
-#define local_irq_restore(x)    do { typecheck(unsigned long,x); __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory", "cc"); } while (0)
-#define local_irq_disable()     __asm__ __volatile__("cli": : :"memory")
-#define local_irq_enable()      __asm__ __volatile__("sti": : :"memory")
-/* used in the idle loop; sti takes one instruction cycle to complete */
-#define safe_halt()             __asm__ __volatile__("sti; hlt": : :"memory")
-/* used when interrupts are already enabled or to shutdown the processor */
-#define halt()                  __asm__ __volatile__("hlt": : :"memory")
-
-#define irqs_disabled()                 \
-({                                      \
-        unsigned long flags;            \
-        local_save_flags(flags);        \
-        !(flags & (1<<9));              \
-})
-
-/* For spinlocks etc */
-#define local_irq_save(x)       __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory")
+#include <linux/irqflags.h>
 
 /*
  * disable hlt during certain critical i/o operations