| Message ID | 20120523135841.22e9dac4@kryten (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Commit | 641bd53a615b35d7a2e9a3de764e7c4953948679 |
| Delegated to: | Michael Ellerman |
| Headers | show |
Index: linux-build/arch/powerpc/configs/ppc64_defconfig =================================================================== --- linux-build.orig/arch/powerpc/configs/ppc64_defconfig 2012-04-05 13:47:45.691857096 +1000 +++ linux-build/arch/powerpc/configs/ppc64_defconfig 2012-05-23 13:14:04.254270594 +1000 @@ -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 Index: linux-build/arch/powerpc/configs/pseries_defconfig =================================================================== --- linux-build.orig/arch/powerpc/configs/pseries_defconfig 2012-04-05 13:47:45.691857096 +1000 +++ linux-build/arch/powerpc/configs/pseries_defconfig 2012-05-23 13:14:59.783222304 +1000 @@ -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
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> ---