powerpc: Enable jump label support

When looking through some instruction traces I noticed our tracepoint checks were inline. It turns out we don't have CONFIG_JUMP_LABEL enabled. By enabling CONFIG_JUMP_LABEL we replace a load/compare/branch with a nop at every tracepoint call. For example in do_IRQ: CONFIG_JUMP_LABEL disabled: stdx 3,11,9 lwz 0,8(29) cmpwi 7,0,0 bne- 7,.L124 bl .irq_enter CONFIG_JUMP_LABEL enabled: stdx 3,11,9 nop bl .irq_enter Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
mariux64 · Jul 3, 2012 · 641bd53 · 641bd53
1 parent 16aaaff
commit 641bd53
Show file tree

Hide file tree

Showing 2 changed files with 2 additions and 0 deletions.
diff --git a/arch/powerpc/configs/ppc64_defconfig b/arch/powerpc/configs/ppc64_defconfig
@@ -16,6 +16,7 @@ CONFIG_BLK_DEV_INITRD=y
 CONFIG_PROFILING=y
 CONFIG_OPROFILE=y
 CONFIG_KPROBES=y
+CONFIG_JUMP_LABEL=y
 CONFIG_MODULES=y
 CONFIG_MODULE_UNLOAD=y
 CONFIG_MODVERSIONS=y

diff --git a/arch/powerpc/configs/pseries_defconfig b/arch/powerpc/configs/pseries_defconfig
@@ -24,6 +24,7 @@ CONFIG_BLK_DEV_INITRD=y
 CONFIG_PROFILING=y
 CONFIG_OPROFILE=y
 CONFIG_KPROBES=y
+CONFIG_JUMP_LABEL=y
 CONFIG_MODULES=y
 CONFIG_MODULE_UNLOAD=y
 CONFIG_MODVERSIONS=y