[PATCH v2] arm64: Disable branch profiling for all arm64 code
Breno Leitao
leitao at debian.org
Wed Jan 7 01:37:36 PST 2026
Hello Steven,
On Tue, Jan 06, 2026 at 11:11:42AM -0500, Steven Rostedt wrote:
> On Tue, 6 Jan 2026 12:24:09 +0000
> Mark Rutland <mark.rutland at arm.com> wrote:
>
>
> > Whoops; s/CONFIG_DEBUG_VIRTUAL/PROFILE_ANNOTATED_BRANCHES/ in both
> > places in my reply.
>
> Note, it could still be useful ;-)
>
> I've been running my yearly branch profiling build on both my main
> workstation and my server. I post the results from my server publicly (this
> is updated every night):
>
> https://rostedt.org/branches/current
>
> If you check out the branch_annotated file, you can see there's still quite
> a bit that gets it wrong. Some of these is because of bad assumptions by
> the developer, others is because the code moved around causing new branches
> to make later annotated branches go the opposite way.
I am starting to look and remove some of these likely/unlikely hint that
are 100% wrong on some very sane configuration (arm64 baremetal hosts
running a webserver).
So far, these are the fixes I have in flight now.
* https://lore.kernel.org/all/20260105-dcache-v1-1-f0d904b4a7c2@debian.org/
* https://lore.kernel.org/all/20260106-blk_unlikely-v1-1-90fb556a6776@debian.org/
* https://lore.kernel.org/all/20260105-annotated_idle-v1-1-10ddf0771b58@debian.org/
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