From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: igc, macOS avoiding signals Date: Sun, 29 Dec 2024 07:51:53 +0200 Message-ID: <86r05rqbnq.fsf@gnu.org> References: <799DDBC5-2C14-4476-B1E0-7BA2FE9E7901@toadstyle.org> <87ldvzg7vi.fsf@protonmail.com> <868qrzsojd.fsf@gnu.org> <87a5cffy8n.fsf@protonmail.com> <864j2nskup.fsf@gnu.org> <861pxrsk1z.fsf@gnu.org> <87v7v3eht9.fsf@protonmail.com> <86wmfjr44o.fsf@gnu.org> <8734i7edhm.fsf@protonmail.com> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="33821"; mail-complaints-to="usenet@ciao.gmane.io" Cc: spd@toadstyle.org, gerd.moellmann@gmail.com, emacs-devel@gnu.org To: Pip Cet Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Dec 29 06:52:48 2024 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1tRmEK-0008ez-Eh for ged-emacs-devel@m.gmane-mx.org; Sun, 29 Dec 2024 06:52:48 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tRmDq-0008JQ-Qw; Sun, 29 Dec 2024 00:52:18 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tRmDo-0008JI-8e for emacs-devel@gnu.org; Sun, 29 Dec 2024 00:52:16 -0500 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tRmDn-0008Bj-2E; Sun, 29 Dec 2024 00:52:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=geqR0bmewNNkbM8gQofs6cr8hSmozQSWE/15VnxdZdA=; b=f7l+czmc/Nw5 lsjjBE4oV3J78sDWX/evvzbHBQ01Ah1YWm2yshyAg0hloBsG736v1+/fmwSULGSg4LlGaXpJmPILX GuBHFIQRrBqkpElCWtMNaylsrViacpp7Kg1MoNUmoQi/dbvWRNmUN7zXIEajQc1J4ZbCG39CV0Bzq ZQ/WW+LXSb4slE25DHT+2E0yuUxtiF8EmLb3SWz8HlYK4zBLSGmNsnYoViMp840KB3YPoQGP0jHlf CAPH+nkJAeJUVJ2u3adXOopTrdFIcdi8hhi1SIOz7MJ4HGnKUT6J3bJUYvtDmdFbF4+y3J3Qq5KN8 vtMfWVzjLXgQnDg5VxDYXg==; In-Reply-To: <8734i7edhm.fsf@protonmail.com> (message from Pip Cet on Sat, 28 Dec 2024 20:54:03 +0000) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:327312 Archived-At: > Date: Sat, 28 Dec 2024 20:54:03 +0000 > From: Pip Cet > Cc: spd@toadstyle.org, gerd.moellmann@gmail.com, emacs-devel@gnu.org > > "Eli Zaretskii" writes: > > >> Date: Sat, 28 Dec 2024 19:20:40 +0000 > >> From: Pip Cet > >> Cc: spd@toadstyle.org, gerd.moellmann@gmail.com, emacs-devel@gnu.org > >> > >> "Eli Zaretskii" writes: > >> > >> > But OTOH, if this delaying of a signal affects responsiveness, then > >> > all we need to do is exempt SIGSEGV from being delayed, right? This > >> > signal-delay mechanism was invented for SIGPROF, SIGCHLD, and SIGALRM, > >> > but there's no reason to delay SIGSEGV. > >> > >> SIGSEGV is never delayed in any proposal I'm aware of. > > > > The call to gc_signal_handler_can_run is inside > > deliver_process_signal. Are you saying that deliver_process_signal is > > not called for SIGSEGV? > > MPS installs its own SIGSEGV handler which doesn't go through > deliver_process_signal. Only if it fails, the Emacs handler which does > go through deliver_process_signal is restored for the final SIGSEGV > which will then terminate Emacs. Then I ask once again: how can we explain what Gerd reports about responsiveness if your changes, which only affect deliver_process_signal, cannot affect MPS? > >> > And AFAIU, on macOS there's no SIGSEGV anyway, is that right? So why > >> > does this delaying affect responsiveness? > >> > >> Possibly SIGPOLL. > > > > We don't need to block SIGPOLL, either. Its handler is safe, the same > > as SIGIO. > > Thanks! That's good to know, and that's why we pass the signal number > to gc_signal_handler_can_run. But currently gc_signal_handler_can_run does nothing with the signal number except recording that it happened. IMO, it should return 'true' immediately unless the signal is SIGPROF, SIGCHLD, or SIGALRM.