dumpstack: x86: various small unification steps

- define STACKSLOTS_PER_LINE and use it
 - define get_bp macro to hide the %%ebp/%%rbp difference
 - i386: check task==NULL in dump_trace, like x86_64
 - i386: show_trace(NULL, ...) uses current automatically
 - x86_64: use [#%d] for die_counter, like i386
 - whitespace and comments

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 6 deletions

diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 7fd32944ceac..13379a988292 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -16,8 +16,11 @@
 
 #include <asm/stacktrace.h>
 
+#define STACKSLOTS_PER_LINE 4
+#define get_bp(bp) asm("movl %%rbp, %0" : "=r" (bp) :)
+
 int panic_on_unrecovered_nmi;
-int kstack_depth_to_print = 12;
+int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE;
 static unsigned int code_bytes = 64;
 static int die_counter;
 
@@ -177,7 +180,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
         if (!bp) {
                 if (task == current) {
                         /* Grab bp right from our regs */
-                        asm("movq %%rbp, %0" : "=r" (bp) : );
+                        get_bp(bp);
                 } else {
                         /* bp is the last reg pushed by switch_to */
                         bp = *(unsigned long *) task->thread.sp;
@@ -329,7 +332,7 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
                 if (((long) stack & (THREAD_SIZE-1)) == 0)
                         break;
                 }
-                if (i && ((i % 4) == 0))
+                if (i && ((i % STACKSLOTS_PER_LINE) == 0))
                         printk("\n%s", log_lvl);
                 printk(" %016lx", *stack++);
                 touch_nmi_watchdog();
@@ -353,7 +356,7 @@ void dump_stack(void)
 
 #ifdef CONFIG_FRAME_POINTER
         if (!bp)
-                asm("movq %%rbp, %0" : "=r" (bp) : );
+                get_bp(bp);
 #endif
 
         printk("Pid: %d, comm: %.20s %s %s %.*s\n",
@@ -396,7 +399,7 @@ void show_registers(struct pt_regs *regs)
 
                 ip = (u8 *)regs->ip - code_prologue;
                 if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
-                        /* try starting at RIP */
+                        /* try starting at IP */
                         ip = (u8 *)regs->ip;
                         code_len = code_len - code_prologue + 1;
                 }
@@ -475,7 +478,7 @@ void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
 
 int __kprobes __die(const char *str, struct pt_regs *regs, long err)
 {
-        printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff, ++die_counter);
+        printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
 #ifdef CONFIG_PREEMPT
         printk("PREEMPT ");
 #endif