From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23C94C433DF for ; Mon, 22 Jun 2020 10:21:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC81A20706 for ; Mon, 22 Jun 2020 10:21:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Vlog8wtK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727770AbgFVKVx (ORCPT ); Mon, 22 Jun 2020 06:21:53 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:60700 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726841AbgFVKVt (ORCPT ); Mon, 22 Jun 2020 06:21:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592821308; 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=7joIPwEiAilajqHGw842bd9Lt4ifvDQJJQVf6KXFIi0=; b=Vlog8wtKKPM7gcaKP+uec60BCzCVpmXRNVxXGMABib6jQs88iVbWNksMlelEo9A32hNw7a k1/25yw8oSf15qj4vM/A0/XNkdV0FSvb8neN8esj21KgER/llsiPRvkjiz3GCT8Uv1GGPJ 3842iCf+KkdeRPw7ePF55kb/wwAH20U= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-252-jzngVRJGPxGHYALO6apD1w-1; Mon, 22 Jun 2020 06:21:46 -0400 X-MC-Unique: jzngVRJGPxGHYALO6apD1w-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 162708018D9; Mon, 22 Jun 2020 10:21:45 +0000 (UTC) Received: from krava (unknown [10.40.193.171]) by smtp.corp.redhat.com (Postfix) with SMTP id 263117167B; Mon, 22 Jun 2020 10:21:42 +0000 (UTC) Date: Mon, 22 Jun 2020 12:21:42 +0200 From: Jiri Olsa To: Alexey Budankov Cc: Arnaldo Carvalho de Melo , Namhyung Kim , Alexander Shishkin , Peter Zijlstra , Ingo Molnar , Andi Kleen , linux-kernel Subject: Re: [PATCH v7 01/13] tools/libperf: introduce notion of static polled file descriptors Message-ID: <20200622102142.GA2583819@krava> References: <49eca46e-4d0e-2ae5-d7d9-e37a4d680270@linux.intel.com> <20200608084344.GA1520715@krava> <2d80a43a-54cf-3d12-92fd-066217c95d76@linux.intel.com> <20200608160758.GD1558310@krava> <20200615123048.GB2088119@krava> <8b29e324-eb8d-2266-562b-ca46aec76a3e@linux.intel.com> <20200615165802.GD2088119@krava> <8351b3ee-d345-a394-d687-443f2d2f7ec4@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8351b3ee-d345-a394-d687-443f2d2f7ec4@linux.intel.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 22, 2020 at 12:47:19PM +0300, Alexey Budankov wrote: SNIP > >>>>>> fdarray__del(array, fdkey); > >>>>> > >>>>> I think there's solution without having filterable type, > >>>>> I'm not sure why you think this is needed > >>>>> > >>>>> I'm busy with other things this week, but I think I can > >>>>> come up with some patch early next week if needed > >>>> > >>>> Friendly reminder. > >>> > >>> hm? I believe we discussed this in here: > >>> https://lore.kernel.org/lkml/20200609145611.GI1558310@krava/ > >> > >> Do you want it to be implemented like in the patch posted by the link? > > > > no idea.. looking for good solution ;-) > > > > how about switching completely to epoll? I tried and it > > does not look that bad > > Well, epoll() is perhaps possible but why does it want switching to epoll()? > What are the benefits and/or specific task being solved by this switch? epoll change fixes the same issues as the patch you took in v8 on top of it it's not a hack and wil make polling more user friendly because of the clear interface > > > > > there might be some loose ends (interface change), but > > I think this would solve our problems with fdarray > > Your first patch accomodated in v8 actually avoids fds typing > and solves pos (=fdarray__add()) staleness issue with fdarray. yea, it was a change meant for discussion (which never happened), and I considered it to be more a hack than a solution I suppose we can live with that for a while, but I'd like to have clean solution for polling as well jirka