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| author | Jiri Kosina <jkosina@suse.cz> | 2010-04-23 04:08:44 +0400 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2010-04-23 04:08:44 +0400 |
| commit | 6c9468e9eb1252eaefd94ce7f06e1be9b0b641b1 (patch) | |
| tree | 797676a336b050bfa1ef879377c07e541b9075d6 /arch/powerpc/kernel/misc.S | |
| parent | 4cb3ca7cd7e2cae8d1daf5345ec99a1e8502cf3f (diff) | |
| parent | c81eddb0e3728661d1585fbc564449c94165cc36 (diff) | |
| download | linux-6c9468e9eb1252eaefd94ce7f06e1be9b0b641b1.tar.xz | |
Merge branch 'master' into for-next
Diffstat (limited to 'arch/powerpc/kernel/misc.S')
| -rw-r--r-- | arch/powerpc/kernel/misc.S | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/misc.S b/arch/powerpc/kernel/misc.S index 2d29752cbe16..22e507c8a556 100644 --- a/arch/powerpc/kernel/misc.S +++ b/arch/powerpc/kernel/misc.S @@ -127,3 +127,29 @@ _GLOBAL(__setup_cpu_power7) _GLOBAL(__restore_cpu_power7) /* place holder */ blr + +/* + * Get a minimal set of registers for our caller's nth caller. + * r3 = regs pointer, r5 = n. + * + * We only get R1 (stack pointer), NIP (next instruction pointer) + * and LR (link register). These are all we can get in the + * general case without doing complicated stack unwinding, but + * fortunately they are enough to do a stack backtrace, which + * is all we need them for. + */ +_GLOBAL(perf_arch_fetch_caller_regs) + mr r6,r1 + cmpwi r5,0 + mflr r4 + ble 2f + mtctr r5 +1: PPC_LL r6,0(r6) + bdnz 1b + PPC_LL r4,PPC_LR_STKOFF(r6) +2: PPC_LL r7,0(r6) + PPC_LL r7,PPC_LR_STKOFF(r7) + PPC_STL r6,GPR1-STACK_FRAME_OVERHEAD(r3) + PPC_STL r4,_NIP-STACK_FRAME_OVERHEAD(r3) + PPC_STL r7,_LINK-STACK_FRAME_OVERHEAD(r3) + blr |