> -----Original Message-----
> From: [email protected] <[email protected]>
> Sent: 21 July 2026 15:29
> To: [email protected]
> Cc: Tamar Christina <[email protected]>; [email protected];
> [email protected]; [email protected]; Kyrylo Tkachov
> <[email protected]>
> Subject: [PATCH] aarch64: Limit Arm SPE probes to PMU events
> 
> From: Kyrylo Tkachov <[email protected]>
> 
> The autoprofile bootstrap support probes for Arm SPE from gcc/configure,
> gcc-auto-profile, and the profile-optimization testsuite support.  Each
> bare "perf list" scans every event class even though arm_spe is a PMU.
> This can make the probe unnecessarily slow on systems with many events.
> 
> Use "perf list pmu" at all three call sites.  The PMU event class filter
> has long been supported by perf and still reports arm_spe.  Stubbed BRBE,
> SPE, and fallback paths select the same profiler as before.
> 
> This patch actually saves a few minutes of end-to-end bootstrap time on my
> SPE
> AArch64 many-core system.
> 
> Ok for trunk?

LGTM.

Thanks,
Tamar

> Thanks,
> Kyrill
> 
> gcc/ChangeLog:
> 
>       * config/aarch64/gcc-auto-profile: Probe for arm_spe with
>       "perf list pmu" instead of "perf list".
>       * configure.ac: Likewise.
>       * configure: Regenerate.
> 
> gcc/testsuite/ChangeLog:
> 
>       * lib/profopt.exp: Likewise.
> 
> Signed-off-by: Kyrylo Tkachov <[email protected]>
> ---
>  gcc/config/aarch64/gcc-auto-profile | 2 +-
>  gcc/configure                       | 2 +-
>  gcc/configure.ac                    | 2 +-
>  gcc/testsuite/lib/profopt.exp       | 2 +-
>  4 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/gcc/config/aarch64/gcc-auto-profile b/gcc/config/aarch64/gcc-
> auto-profile
> index 8f7502b30e3..6e33047698c 100755
> --- a/gcc/config/aarch64/gcc-auto-profile
> +++ b/gcc/config/aarch64/gcc-auto-profile
> @@ -45,7 +45,7 @@ if [ "$use_brbe" = true ] ; then
>    set -x
>    perf record --inherit -o perf.data -j any,$FLAGS "$@"
>    set +x
> -elif [ -n "$(perf list | grep arm_spe)" ] ; then
> +elif [ -n "$(perf list pmu | grep arm_spe)" ]; then
>    echo >&2 "Info: Using SPE to collect branch profiles"
>    set -x
>    perf record --inherit -o perf.data -e arm_spe_0/branch_filter=1/ "$@"
> diff --git a/gcc/configure b/gcc/configure
> index 8f2ecfcffdc..cf2dfd99235 100755
> --- a/gcc/configure
> +++ b/gcc/configure
> @@ -35189,7 +35189,7 @@ $as_echo_n "checking AArch64 build supports
> SPE profiling for autoprofiledbootst
>       if test ! -n "$($PERF record -j any,u -o /dev/null /bin/true 2>&1 | grep
> "PMU Hardware or event type doesn't support branch stack sampling.")";
> then
>         AFDO_PROFILER=perf
>         aarch64_spe_support="using BRBE instead"
> -     elif test -n "$($PERF list | grep arm_spe)"; then
> +     elif test -n "$($PERF list pmu | grep arm_spe)"; then
>         AFDO_PROFILER=perf_spe
>         aarch64_spe_support=yes
>       fi
> diff --git a/gcc/configure.ac b/gcc/configure.ac
> index 030ee373a6a..77ec150c3e2 100644
> --- a/gcc/configure.ac
> +++ b/gcc/configure.ac
> @@ -7881,7 +7881,7 @@ if test x$PERF != xno; then
>       if test ! -n "$($PERF record -j any,u -o /dev/null /bin/true 2>&1 | grep
> "PMU Hardware or event type doesn't support branch stack sampling.")";
> then
>         AFDO_PROFILER=perf
>         aarch64_spe_support="using BRBE instead"
> -     elif test -n "$($PERF list | grep arm_spe)"; then
> +     elif test -n "$($PERF list pmu | grep arm_spe)"; then
>         AFDO_PROFILER=perf_spe
>         aarch64_spe_support=yes
>       fi
> diff --git a/gcc/testsuite/lib/profopt.exp b/gcc/testsuite/lib/profopt.exp
> index 4f3f61958aa..cd80d5e9402 100644
> --- a/gcc/testsuite/lib/profopt.exp
> +++ b/gcc/testsuite/lib/profopt.exp
> @@ -456,7 +456,7 @@ proc profopt-execute { src } {
>                  set bprefix "afdo."
>               set compiler [lindex $GCC_UNDER_TEST 0]
>               set autofdo_version [string trim [lindex [remote_exec target
> "$compiler --print-autofdo-gcov-version"] 1] ]
> -             set profiler_check [string trim [lindex [remote_exec target
> "perf --no-pager list | grep arm_spe"] 1]]
> +             set profiler_check [string trim [lindex [remote_exec target
> "perf --no-pager list pmu | grep arm_spe"] 1]]
>               if {$profiler_check ne ""} {
>                   set profiler "perf_spe"
>               } else {
> --
> 2.50.1 (Apple Git-155)

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