On Nov 29 20:59, Takashi Yano wrote: > Previously, the sig thread ran in THREAD_PRIORITY_HIGHEST priority. > This causes a critical delay in the signal handling in the main > thread if too many signals are received rapidly and the CPU is very > busy. In this case, most of the CPU time is allocated to the sig > thread, so the main thread cannot have a chance of handling signals. > With this patch, to avoid such a situation, the priority of the sig > thread is set to THREAD_PRIORITY_NORMAL priority. Furthermore, if > the signal is alerted to the main thread, but the main thread does > not handle it yet, to increase the chance of handling it in the main > thread, reduce the sig thread priority to THREAD_PRIORITY_LOWEST > priority temporarily before calling _cygtls::handle_SIGCONT(). > > Addresses: https://cygwin.com/pipermail/cygwin/2024-November/256744.html > Fixes: 53ad6f1394aa ("(cygthread::cygthread): Use three only arguments for > detached threads, and start the thread via QueueUserAPC/async_create.") > Reported-by: Christian Franke <christian.fra...@t-online.de> > Reviewed-by: Corinna Vinschen <cori...@vinschen.de> > Signed-off-by: Takashi Yano <takashi.y...@nifty.ne.jp> > --- > winsup/cygwin/exceptions.cc | 6 ++++++ > winsup/cygwin/sigproc.cc | 1 + > 2 files changed, 7 insertions(+) > > diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc > index 0f8c21939..7fc644af1 100644 > --- a/winsup/cygwin/exceptions.cc > +++ b/winsup/cygwin/exceptions.cc > @@ -978,6 +978,9 @@ sigpacket::setup_handler (void *handler, struct > sigaction& siga, _cygtls *tls) > CONTEXT cx; > bool interrupted = false; > > + for (int i = 0; i < 100 && tls->current_sig; i++) > + yield (); > +
Is that a piece of stray code left from testing, or is that actually part of the patch? The commit message doesn't explain it... Thanks, Corinna
