This patch series applies on top of Peter Zijlstras' latest unwind user
enhancements (and perf deferred callchain support) on his tip perf/core
branch:

  git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf/core

Which has already been merged to tip/master and linux-next/master.

Patch 1 enhances a few comments in unwind_user_next_common().

Patch 2 gets rid of an ifdef in unwind_user_next_fp() by moving it to
linux/unwind_user.h.  Additionally it provides a common fallback for
unwind_user_at_function_start().

Patch 3 ensures the x86 unwind_user_word_size() implementation is
available whenever config option UNWIND_USER is enabled, as it is
required by unwind user in general and is not specific to its FP
unwind method.

Patch 4 (new in v4) simplifies unwind_user_word_size().

Regards,
Jens

Jens Remus (4):
  unwind_user: Enhance comments on get CFA, FP, and RA
  unwind_user/fp: Use dummies instead of ifdef
  x86/unwind_user: Guard unwind_user_word_size() by UNWIND_USER
  x86/unwind_user: Simplify unwind_user_word_size()

 arch/x86/include/asm/unwind_user.h | 27 ++++++++++++++-------------
 include/linux/unwind_user.h        | 18 ++++++++++++++++--
 kernel/unwind/user.c               | 12 ++++--------
 3 files changed, 34 insertions(+), 23 deletions(-)

-- 
2.51.0

On Mon, Dec 08, 2025 at 05:03:48PM +0100, Jens Remus wrote:
> This patch series applies on top of Peter Zijlstras' latest unwind user
> enhancements (and perf deferred callchain support) on his tip perf/core
> branch:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf/core
> 
> Which has already been merged to tip/master and linux-next/master.

Right, that should be empty now :-)


> Jens Remus (4):
>   unwind_user: Enhance comments on get CFA, FP, and RA
>   unwind_user/fp: Use dummies instead of ifdef
>   x86/unwind_user: Guard unwind_user_word_size() by UNWIND_USER
>   x86/unwind_user: Simplify unwind_user_word_size()
> 
>  arch/x86/include/asm/unwind_user.h | 27 ++++++++++++++-------------
>  include/linux/unwind_user.h        | 18 ++++++++++++++++--
>  kernel/unwind/user.c               | 12 ++++--------
>  3 files changed, 34 insertions(+), 23 deletions(-)

I'll go stick these patches in tip/perf/core after rc1 or so, no real
hurry with these, right?

Hello Peter!

On 12/8/2025 8:36 PM, Peter Zijlstra wrote:
> On Mon, Dec 08, 2025 at 05:03:48PM +0100, Jens Remus wrote:

>> Jens Remus (4):
>>   unwind_user: Enhance comments on get CFA, FP, and RA
>>   unwind_user/fp: Use dummies instead of ifdef
>>   x86/unwind_user: Guard unwind_user_word_size() by UNWIND_USER
>>   x86/unwind_user: Simplify unwind_user_word_size()
>>
>>  arch/x86/include/asm/unwind_user.h | 27 ++++++++++++++-------------
>>  include/linux/unwind_user.h        | 18 ++++++++++++++++--
>>  kernel/unwind/user.c               | 12 ++++--------
>>  3 files changed, 34 insertions(+), 23 deletions(-)
> 
> I'll go stick these patches in tip/perf/core after rc1 or so, no real
> hurry with these, right?
Perfect, that is fine with me.

Thanks and regards,
Jens
-- 
Jens Remus
Linux on Z Development (D3303)
+49-7031-16-1128 Office
jremus@de.ibm.com

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