[PATCH v4 4/5] x86: Clean up current_stack_pointer

Andy Lutomirski
2014-11-21T21:27:18Z

There's no good reason for it to be a macro, and x86_64 will want to
use it, so it should be in a header.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
---
arch/x86/include/asm/thread_info.h | 11 +++++++++++
arch/x86/kernel/irq_32.c | 13 +++----------
2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 547e344a6dc6..8b13b0fbda8e 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -170,6 +170,17 @@ static inline struct thread_info *current_thread_info(void)
return ti;
}

+static inline unsigned long current_stack_pointer(void)
+{
+ unsigned long sp;
+#ifdef CONFIG_X86_64
+ asm("mov %%rsp,%0" : "=g" (sp));
+#else
+ asm("mov %%esp,%0" : "=g" (sp));
+#endif
+ return sp;
+}
+
#else /* !__ASSEMBLY__ */

/* how to get the thread information struct from ASM */
diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index 63ce838e5a54..28d28f5eb8f4 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -69,16 +69,9 @@ static void call_on_stack(void *func, void *stack)
: "memory", "cc", "edx", "ecx", "eax");
}

-/* how to get the current stack pointer from C */
-#define current_stack_pointer ({ \
- unsigned long sp; \
- asm("mov %%esp,%0" : "=g" (sp)); \
- sp; \
-})
-
static inline void *current_stack(void)
{
- return (void *)(current_stack_pointer & ~(THREAD_SIZE - 1));
+ return (void *)(current_stack_pointer() & ~(THREAD_SIZE - 1));
}

static inline int
@@ -103,7 +96,7 @@ execute_on_irq_stack(int overflow, struct irq_desc *desc, int irq)

/* Save the next esp at the bottom of the stack */
prev_esp = (u32 *)irqstk;
- *prev_esp = current_stack_pointer;
+ *prev_esp = current_stack_pointer();

if (unlikely(overflow))
call_on_stack(print_stack_overflow, isp);
@@ -156,7 +149,7 @@ void do_softirq_own_stack(void)

/* Push the previous esp onto the stack */
prev_esp = (u32 *)irqstk;
- *prev_esp = current_stack_pointer;
+ *prev_esp = current_stack_pointer();

call_on_stack(__do_softirq, isp);
}
--
1.9.3