x86/unwind: Make CONFIG_UNWINDER_ORC=y the default in kconfig for 64-bit

The ORC unwinder has been stable in testing so far.  Give it much wider
testing by making it the default in kconfig for x86_64.  It's not yet
supported for 32-bit, so leave frame pointers as the default there.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/9b1237bbe7244ed9cdf8db2dcb1253e37e1c341e.1507924831.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Josh Poimboeuf 2017-10-13 15:02:01 -05:00 committed by Ingo Molnar
parent 11af847446
commit fc72ae40e3

View file

@ -358,27 +358,13 @@ config PUNIT_ATOM_DEBUG
choice
prompt "Choose kernel unwinder"
default UNWINDER_FRAME_POINTER
default UNWINDER_ORC if X86_64
default UNWINDER_FRAME_POINTER if X86_32
---help---
This determines which method will be used for unwinding kernel stack
traces for panics, oopses, bugs, warnings, perf, /proc/<pid>/stack,
livepatch, lockdep, and more.
config UNWINDER_FRAME_POINTER
bool "Frame pointer unwinder"
select FRAME_POINTER
---help---
This option enables the frame pointer unwinder for unwinding kernel
stack traces.
The unwinder itself is fast and it uses less RAM than the ORC
unwinder, but the kernel text size will grow by ~3% and the kernel's
overall performance will degrade by roughly 5-10%.
This option is recommended if you want to use the livepatch
consistency model, as this is currently the only way to get a
reliable stack trace (CONFIG_HAVE_RELIABLE_STACKTRACE).
config UNWINDER_ORC
bool "ORC unwinder"
depends on X86_64
@ -395,6 +381,21 @@ config UNWINDER_ORC
Enabling this option will increase the kernel's runtime memory usage
by roughly 2-4MB, depending on your kernel config.
config UNWINDER_FRAME_POINTER
bool "Frame pointer unwinder"
select FRAME_POINTER
---help---
This option enables the frame pointer unwinder for unwinding kernel
stack traces.
The unwinder itself is fast and it uses less RAM than the ORC
unwinder, but the kernel text size will grow by ~3% and the kernel's
overall performance will degrade by roughly 5-10%.
This option is recommended if you want to use the livepatch
consistency model, as this is currently the only way to get a
reliable stack trace (CONFIG_HAVE_RELIABLE_STACKTRACE).
config UNWINDER_GUESS
bool "Guess unwinder"
depends on EXPERT