Date: Fri, 12 May 2017 15:35:00 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r318243 - head/sys/kern Message-ID: <201705121535.v4CFZ0eL094172@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: kib Date: Fri May 12 15:34:59 2017 New Revision: 318243 URL: https://svnweb.freebsd.org/changeset/base/318243 Log: Do not wake up sleeping thread in reschedule_signals() if the signal is blocked. The spurious wakeup might result in spurious EINTR. The reschedule_signals() function is called when the calling thread has the signal mask changed. For each newly blocked signal, we try to find a thread which might have the signal not blocked. If no such thread exists, sigtd() returns random thread, which must not be waken up. I decided that re-checking, as suggested by PR submitter, is more reasonable change than to change sigtd() interface, due to other uses of sigtd(). signotify() already performs this check. Submitted by: Duane <parakleta@darkreality.org> PR: 219228 Sponsored by: The FreeBSD Foundation MFC after: 1 week Modified: head/sys/kern/kern_sig.c Modified: head/sys/kern/kern_sig.c ============================================================================== --- head/sys/kern/kern_sig.c Fri May 12 15:20:12 2017 (r318242) +++ head/sys/kern/kern_sig.c Fri May 12 15:34:59 2017 (r318243) @@ -2646,7 +2646,9 @@ reschedule_signals(struct proc *p, sigse signotify(td); if (!(flags & SIGPROCMASK_PS_LOCKED)) mtx_lock(&ps->ps_mtx); - if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig)) + if (p->p_flag & P_TRACED || + (SIGISMEMBER(ps->ps_sigcatch, sig) && + !SIGISMEMBER(td->td_sigmask, sig))) tdsigwakeup(td, sig, SIG_CATCH, (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR : ERESTART));
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201705121535.v4CFZ0eL094172>