[PATCH 1/3] chainlint.pl: make CPU count computation more robust
- From
- Eric Sunshine <ericsunshine@charter.net>
- Date
- May 20, 2024, 19:01 UTC
- Message-ID
- <20240520190131.94904-2-ericsunshine@charter.net>
- In-Reply-To
- <20240520190131.94904-1-ericsunshine@charter.net>
From: Eric Sunshine <sunshine@sunshineco.com>
There have been reports[1,2] of chainlint.pl failing to produce output when output is expected. In fact, the underlying problem is more severe: in these cases, it isn't doing any work at all, thus not checking Git tests for semantic problems. In the reported cases, the problem was tracked down to ncores() returning 0 for the CPU count, which resulted in chainlint.pl not performing any work (since it thought it had no cores on which to process).
In the reported cases, the reason for the failure was that the regular expression counting the number of processors reported by /proc/cpuinfo failed to find any matches, hence it counted 0 processors. Although fixing each case as it is reported allows chaining.pl to work correctly on that architecture, it does nothing to improve the overall robustness of the core count computation which may still return 0 on some yet untested architecture.
Address this shortcoming by ensuring that ncores() returns a sensible fallback value in all cases.
[1]: https://lore.kernel.org/git/pull.1385.git.git.1669148861635.gitgitgadget@gmail.com/ [2]: https://lore.kernel.org/git/8baa12f8d044265f1ddeabd64209e7ac0d3700ae.camel@physik.fu-berlin.de/
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> --- t/chainlint.pl | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-)
diff --git a/t/chainlint.pl b/t/chainlint.pl index 556ee91a15..d9a2691889 100755 --- a/t/chainlint.pl +++ b/t/chainlint.pl @@ -716,11 +716,22 @@ sub fd_colors { sub ncores { # Windows - return $ENV{NUMBER_OF_PROCESSORS} if exists($ENV{NUMBER_OF_PROCESSORS}); + if (exists($ENV{NUMBER_OF_PROCESSORS})) { + my $ncpu = $ENV{NUMBER_OF_PROCESSORS}; + return $ncpu > 0 ? $ncpu : 1; + } # Linux / MSYS2 / Cygwin / WSL - do { local @ARGV='/proc/cpuinfo'; return scalar(grep(/^processor[\s\d]*:/, <>)); } if -r '/proc/cpuinfo'; + if (open my $fh, '<', '/proc/cpuinfo') { + my $cpuinfo = do { local $/; <$fh> }; + close($fh); + my @matches = ($cpuinfo =~ /^processor[\s\d]*:/mg); + return @matches ? scalar(@matches) : 1; + } # macOS & BSD - return qx/sysctl -n hw.ncpu/ if $^O =~ /(?:^darwin$|bsd)/; + if ($^O =~ /(?:^darwin$|bsd)/) { + my $ncpu = qx/sysctl -n hw.ncpu/; + return $ncpu > 0 ? $ncpu : 1; + } return 1; }
-- 2.45.1