From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E81CC437464 for ; Mon, 3 Aug 2026 13:55:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785765343; cv=none; b=DSLtrnzRZZ3TEhLnuG95pE87Lo3NarqE9mRtXf4aFSAmFubUzW/+yVfLy/2bCw1MPZND52HIvIZkpp+FLgt5nF9tlQTKziDENJcD934eRmAiK75hy74giL+eSJ+kt8SCs4BG3P6Zljvz1TY1QVSBJWKHNhOz8pcbIjRh0RFVCrg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785765343; c=relaxed/simple; bh=ohIrLmoxVr5tnVZM/5oGCbWYfqqwCWf8kPcBFDBNHD8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=kwa0+HlYk38tG43xwNoMnPBh53bUJRUjx6f7vF4v/237pHP5wsey4Pg9acJ+eSCJxAHoQ5qQ+tK7CpoVDJA9Pm/S/XeiZz6hD6tN+um0x+FxPR+JbQ/rI9SE4aidnYeW9tiCzBFfv3HxNC/eXcqjrZtEXHys1LRswylN/cQvL7w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=G4BER5tM; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="G4BER5tM" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1785765341; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UoyylC6PDB7KB3heBT5Hc28Pw85gPcmsDD9p3R1sx5g=; b=G4BER5tMsJ0IU/8Lha1n4eGMDIP11rwPRL4MhCmM6OzBcJezrpMMs7KN5lEEAwiXaSl7Uz IsQNe+El6r9RSak7bnei9VpONuIYvzEAZQub8GSggIFkm4Y1PuRs7UshM7LXOMFTIKz1C8 WwirwIf4ygBY/cuscFRJ5rMuywwD7uk= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-371-CFhcpMnxOgiKIB3ceW9lag-1; Mon, 03 Aug 2026 09:55:31 -0400 X-MC-Unique: CFhcpMnxOgiKIB3ceW9lag-1 X-Mimecast-MFC-AGG-ID: CFhcpMnxOgiKIB3ceW9lag_1785765327 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C954418002E6; Mon, 3 Aug 2026 13:55:26 +0000 (UTC) Received: from fedora (unknown [10.44.32.54]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id 5242A18004AD; Mon, 3 Aug 2026 13:55:21 +0000 (UTC) Received: by fedora (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Mon, 3 Aug 2026 15:55:26 +0200 (CEST) Date: Mon, 3 Aug 2026 15:55:20 +0200 From: Oleg Nesterov To: Breno Leitao Cc: Christian Brauner , Jens Axboe , Linus Torvalds , Mateusz Guzik , Pavel Begunkov , Alexander Viro , Jan Kara , Alexey Gladkov , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, io-uring@vger.kernel.org Subject: Re: [PATCH v4] pipe: only enable the extra wake_up(rd_wait) for EPOLLET consumers Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 On 08/03, Breno Leitao wrote: > > On Mon, Aug 03, 2026 at 02:46:25PM +0200, Oleg Nesterov wrote: > > + * Currently io_uring sets EPOLLET for multishot polls, so it gets the > > + * same behaviour. > > I got the impression that Linus wanted the comment epoll-only, and > wanted the io_uring case treated as something to remove, not to bless. Well, perhaps I misunderstood Linus... but it seems he was fine with this comment which I showed in https://lore.kernel.org/all/am9an4HWPGaxmbcK@redhat.com/ And. This comment (and the test-case in the changelog) doesn't try to bless the current behaviour, it only tries to document the "status quo". Let me also quote my other reply to Linus: > The only reason that ugly hack exists is because we did have that > break user space. If we can get rid of th eugly hack for io_uring, > that would only be a good thing. Perhaps, I can't really comment. But it seems to me that in this case it would make more sense to change the logic in io_uring/ rather than in pipe_poll(). And this needs a separate change. Oleg.