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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 C12EBC4360F for ; Thu, 7 Mar 2019 12:14:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9911120675 for ; Thu, 7 Mar 2019 12:14:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726378AbfCGMOc (ORCPT ); Thu, 7 Mar 2019 07:14:32 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40652 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726127AbfCGMOc (ORCPT ); Thu, 7 Mar 2019 07:14:32 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 42C143084299; Thu, 7 Mar 2019 12:14:32 +0000 (UTC) Received: from krava (unknown [10.43.17.112]) by smtp.corp.redhat.com (Postfix) with SMTP id 91B204142; Thu, 7 Mar 2019 12:14:30 +0000 (UTC) Date: Thu, 7 Mar 2019 13:14:29 +0100 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 v5 07/10] perf record: implement -z,--compression_level=n option and compression Message-ID: <20190307121429.GB29474@krava> References: <4d1b11a4-77ed-d9af-ed22-875fc17b6050@linux.intel.com> <87fa1906-2d6a-a00a-7ba5-b570d0cbf9cc@linux.intel.com> <20190305122534.GB16615@krava> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Thu, 07 Mar 2019 12:14:32 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 07, 2019 at 11:39:46AM +0300, Alexey Budankov wrote: > > On 05.03.2019 15:25, Jiri Olsa wrote: > > On Fri, Mar 01, 2019 at 06:58:32PM +0300, Alexey Budankov wrote: > > > > SNIP > > > >> > >> /* > >> * Increment md->refcount to guard md->data[idx] buffer > >> @@ -350,7 +357,7 @@ int perf_mmap__aio_push(struct perf_mmap *md, void *to, int idx, > >> md->prev = head; > >> perf_mmap__consume(md); > >> > >> - rc = push(to, &md->aio.cblocks[idx], md->aio.data[idx], size0 + size, *off); > >> + rc = push(to, md->aio.data[idx], size0 + size, *off, &md->aio.cblocks[idx]); > >> if (!rc) { > >> *off += size0 + size; > >> } else { > >> @@ -556,13 +563,15 @@ int perf_mmap__read_init(struct perf_mmap *map) > >> } > >> > >> int perf_mmap__push(struct perf_mmap *md, void *to, > >> - int push(struct perf_mmap *map, void *to, void *buf, size_t size)) > >> + int push(struct perf_mmap *map, void *to, void *buf, size_t size), > >> + perf_mmap__compress_fn_t compress, void *comp_data) > >> { > >> u64 head = perf_mmap__read_head(md); > >> unsigned char *data = md->base + page_size; > >> unsigned long size; > >> void *buf; > >> int rc = 0; > >> + size_t mmap_len = perf_mmap__mmap_len(md); > >> > >> rc = perf_mmap__read_init(md); > >> if (rc < 0) > >> @@ -574,7 +583,10 @@ int perf_mmap__push(struct perf_mmap *md, void *to, > >> buf = &data[md->start & md->mask]; > >> size = md->mask + 1 - (md->start & md->mask); > >> md->start += size; > >> - > >> + if (compress) { > >> + size = compress(comp_data, md->data, mmap_len, buf, size); > >> + buf = md->data; > >> + } > >> if (push(md, to, buf, size) < 0) { > >> rc = -1; > >> goto out; > > > > when we discussed the compress callback should be another layer > > in perf_mmap__push I was thinking more of the layered/fifo design, > > like: > > > > normaly we call: > > > > perf_mmap__push(... push = record__pushfn ...) > > -> reads mmap data and calls push(data), which translates as: > > > > record__pushfn(data); > > - which stores the data > > > > > > for compressed it'd be: > > > > perf_mmap__push(... push = compressed_push ...) > > > > -> reads mmap data and calls push(data), which translates as: > > > > compressed_push(data) > > -> reads data, compresses them and calls, next push callback in line: > > > > record__pushfn(data) > > - which stores the data > > > > > > there'd need to be the logic for compressed_push to > > remember the 'next push' function > > That is suboptimal for AIO. Also compression is an independent operation that > could be applied on any of push stages you mean. not sure what you mean by suboptimal, but I think that it can still happen in subsequent push callback > > > > > but I think this was the original idea behind the > > perf_mmap__push -> it gets the data and pushes them for > > the next processing.. it should stay as simple as that > > Agree on keeping simplicity and, at the moment, there is no any push to the next > processing in the code so provided implementation fits as for serial as for AIO > at the same time sticking to simplicity as much as possibly. If you see something > that would fit better please speak up and share. I have to insist that perf_mmap__push stays untouched and we do other processing in the push callbacks jirka