[PATCH 0/3] arm64: perf: Make compat tracing better

From: Douglas Anderson
Date: Fri May 07 2021 - 16:55:42 EST


The goal for this series is to improve "perf" behavior when 32-bit
userspace code is involved. This turns out to be fairly important for
Chrome OS which still runs 32-bit userspace for the time being (long
story there).

I won't repeat everything said in the individual patches since since
they are wordy enough as it is.

Please enjoy and I hope this isn't too ugly/hacky for inclusion in
mainline.

Thanks to Nick Desaulniers for his early review of these patches and
to Ricky for the super early prototype that some of this is based on.


Douglas Anderson (3):
arm64: perf: perf_callchain_user() compat support for
clang/non-APCS-gcc-arm
arm64: perf: Improve compat perf_callchain_user() for clang leaf
functions
arm64: perf: Add a config option saying 32-bit thumb code uses R11 for
FP

arch/arm64/Kconfig | 12 ++
arch/arm64/kernel/perf_callchain.c | 329 +++++++++++++++++++++++++----
2 files changed, 305 insertions(+), 36 deletions(-)

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2.31.1.607.g51e8a6a459-goog