| commit | 2053c11331991818882f7cf023ed2ce4ff44b274 | |
| author | Adhemerval Zanella Netto <adhemerval.zanella@linaro.org> | |
| Thu, 12 Jan 2023 13:58:51 +0000 (12 10:58 -0300) | ||
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | |
| Wed, 1 Feb 2023 11:42:11 +0000 (1 08:42 -0300) | ||
| tree | b1edaafb8036456c39bff1756ed8827922c0b3b5 | treesnapshot (tar.gz zip) |
| parent | 2290cf73cce1292d9345a8183fd29ae3994a9481 | commitdiff |
linux: Add clone3 CLONE_CLEAR_SIGHAND optimization to posix_spawn
The clone3 flag resets all signal handlers of the child not set to
SIG_IGN to SIG_DFL. It allows to skip most of the sigaction calls
to setup child signal handling, where previously a posix_spawn
had to issue 2 times NSIG sigaction calls (one to obtain the current
disposition and another to set either SIG_DFL or SIG_IGN).
With POSIX_SPAWN_SETSIGDEF the child will setup the signal for the case
where the disposition is SIG_IGN.
The code must handle the fallback where clone3 is not available. This is
done by splitting __clone_internal_fallback from __clone_internal.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The clone3 flag resets all signal handlers of the child not set to
SIG_IGN to SIG_DFL. It allows to skip most of the sigaction calls
to setup child signal handling, where previously a posix_spawn
had to issue 2 times NSIG sigaction calls (one to obtain the current
disposition and another to set either SIG_DFL or SIG_IGN).
With POSIX_SPAWN_SETSIGDEF the child will setup the signal for the case
where the disposition is SIG_IGN.
The code must handle the fallback where clone3 is not available. This is
done by splitting __clone_internal_fallback from __clone_internal.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>