From: Eric Sunshine Date: Mon, 20 May 2024 19:01:31 GMT Subject: [PATCH 3/3] chainlint.pl: latch CPU count directly reported by /proc/cpuinfo Message-ID: <20240520190131.94904-4-ericsunshine@charter.net> In-Reply-To: <20240520190131.94904-1-ericsunshine@charter.net> From: Eric Sunshine On Linux, ncores() computes the number of CPUs by counting the "processor" or "CPU" lines emitted by /proc/cpuinfo. However, on some platforms, /proc/cpuinfo does not enumerate the CPUs at all, but instead merely mentions the total number of CPUs. In such cases, pluck the CPU count directly from the /proc/cpuinfo line which reports the number of active CPUs. (In particular, check for "cpus active: NN" and "ncpus active: NN" since both variants have been seen in the wild[1,2].) [1]: https://lore.kernel.org/git/503a99f3511559722a3eeef15d31027dfe617fa1.camel@physik.fu-berlin.de/ [2]: https://lore.kernel.org/git/7acbd5c6c68bd7ba020e2d1cc457a8954fd6edf4.camel@physik.fu-berlin.de/ Reported-by: John Paul Adrian Glaubitz Signed-off-by: Eric Sunshine --- t/chainlint.pl | 3 +++ 1 file changed, 3 insertions(+) diff --git a/t/chainlint.pl b/t/chainlint.pl index d593cb95e7..1bbd985b78 100755 --- a/t/chainlint.pl +++ b/t/chainlint.pl @@ -724,6 +724,9 @@ sub ncores { if (open my $fh, '<', '/proc/cpuinfo') { my $cpuinfo = do { local $/; <$fh> }; close($fh); + if ($cpuinfo =~ /^n?cpus active\s*:\s*(\d+)/m) { + return $1 if $1 > 0; + } my @matches = ($cpuinfo =~ /^(processor|CPU)[\s\d]*:/mg); return @matches ? scalar(@matches) : 1; } -- 2.45.1