Merge branch 'perf/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/frede...

[pandora-kernel.git] / arch / x86 / kernel / entry_64.S

diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 8a445a0..d656f68 100644 (file)
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -297,27 +297,26 @@ ENDPROC(native_usergs_sysret64)
        .endm
 
 /* save partial stack frame */
-       .pushsection .kprobes.text, "ax"
-ENTRY(save_args)
-       XCPT_FRAME
+       .macro SAVE_ARGS_IRQ
        cld
-       /*
-        * start from rbp in pt_regs and jump over
-        * return address.
-        */
-       movq_cfi rdi, RDI+8-RBP
-       movq_cfi rsi, RSI+8-RBP
-       movq_cfi rdx, RDX+8-RBP
-       movq_cfi rcx, RCX+8-RBP
-       movq_cfi rax, RAX+8-RBP
-       movq_cfi  r8,  R8+8-RBP
-       movq_cfi  r9,  R9+8-RBP
-       movq_cfi r10, R10+8-RBP
-       movq_cfi r11, R11+8-RBP
-
-       leaq -RBP+8(%rsp),%rdi  /* arg1 for handler */
-       movq_cfi rbp, 8         /* push %rbp */
-       leaq 8(%rsp), %rbp              /* mov %rsp, %ebp */
+       /* start from rbp in pt_regs and jump over */
+       movq_cfi rdi, RDI-RBP
+       movq_cfi rsi, RSI-RBP
+       movq_cfi rdx, RDX-RBP
+       movq_cfi rcx, RCX-RBP
+       movq_cfi rax, RAX-RBP
+       movq_cfi  r8,  R8-RBP
+       movq_cfi  r9,  R9-RBP
+       movq_cfi r10, R10-RBP
+       movq_cfi r11, R11-RBP
+
+       /* Save rbp so that we can unwind from get_irq_regs() */
+       movq_cfi rbp, 0
+
+       /* Save previous stack value */
+       movq %rsp, %rsi
+
+       leaq -RBP(%rsp),%rdi    /* arg1 for handler */
        testl $3, CS(%rdi)
        je 1f
        SWAPGS
@@ -329,19 +328,14 @@ ENTRY(save_args)
         */
 1:     incl PER_CPU_VAR(irq_count)
        jne 2f
-       popq_cfi %rax                   /* move return address... */
        mov PER_CPU_VAR(irq_stack_ptr),%rsp
        EMPTY_FRAME 0
-       pushq_cfi %rbp                  /* backlink for unwinder */
-       pushq_cfi %rax                  /* ... to the new stack */
-       /*
-        * We entered an interrupt context - irqs are off:
-        */
-2:     TRACE_IRQS_OFF
-       ret
-       CFI_ENDPROC
-END(save_args)
-       .popsection
+
+2:     /* Store previous stack value */
+       pushq %rsi
+       /* We entered an interrupt context - irqs are off: */
+       TRACE_IRQS_OFF
+       .endm
 
 ENTRY(save_rest)
        PARTIAL_FRAME 1 REST_SKIP+8
@@ -791,7 +785,7 @@ END(interrupt)
        /* reserve pt_regs for scratch regs and rbp */
        subq $ORIG_RAX-RBP, %rsp
        CFI_ADJUST_CFA_OFFSET ORIG_RAX-RBP
-       call save_args
+       SAVE_ARGS_IRQ
        PARTIAL_FRAME 0
        call \func
        .endm
@@ -814,15 +808,14 @@ ret_from_intr:
        DISABLE_INTERRUPTS(CLBR_NONE)
        TRACE_IRQS_OFF
        decl PER_CPU_VAR(irq_count)
-       leaveq
 
-       CFI_RESTORE             rbp
+       /* Restore saved previous stack */
+       popq %rsi
+       leaq 16(%rsi), %rsp
+
        CFI_DEF_CFA_REGISTER    rsp
-       CFI_ADJUST_CFA_OFFSET   -8
+       CFI_ADJUST_CFA_OFFSET   -16
 
-       /* we did not save rbx, restore only from ARGOFFSET */
-       addq $8, %rsp
-       CFI_ADJUST_CFA_OFFSET   -8
 exit_intr:
        GET_THREAD_INFO(%rcx)
        testl $3,CS-ARGOFFSET(%rsp)