On Mon, 25 Nov 2024 21:16:20 +0900 Takashi Yano wrote: > Previously, sig thread ran in THREAD_PRIORITY_HIGHEST priority. > This caused critical delay in signal handling in the main thread > if the too many signales are received rapidly and CPU is very busy. > I this case, most of CPU time is allocated to sig thread, so the > main thread cannot have a chance to handle signals. With this patch, > the sig thread priority is set to the same priority with main thread > to avoid such situation. Furthermore, if the signal is alarted to > the main thread, but main thread does not handle it yet, in order to > increase the chance to handle it in the main thread, reduce the sig > thread priority is to THREAD_PRIORITY_LOWEST temporarily. > > 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: > Signed-off-by: Takashi Yano <takashi.y...@nifty.ne.jp> > --- > winsup/cygwin/sigproc.cc | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/winsup/cygwin/sigproc.cc b/winsup/cygwin/sigproc.cc > index 541f90cb7..75a5142fd 100644 > --- a/winsup/cygwin/sigproc.cc > +++ b/winsup/cygwin/sigproc.cc > @@ -1327,6 +1327,10 @@ wait_sig (VOID *) > { > DWORD nb; > sigpacket pack = {}; > + /* Follow to the main thread priority */ > + int prio = GetThreadPriority (OpenThread (THREAD_QUERY_INFORMATION, > + FALSE, _main_tls->thread_id)); > + SetThreadPriority (GetCurrentThread (), prio);
Oops! I forgot to close thread handle. I will submit v2 patch. -- Takashi Yano <takashi.y...@nifty.ne.jp>
