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=-13.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,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 91963C282CE for ; Wed, 22 May 2019 21:23:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4002A20821 for ; Wed, 22 May 2019 21:23:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730478AbfEVVXE (ORCPT ); Wed, 22 May 2019 17:23:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46270 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729483AbfEVVXE (ORCPT ); Wed, 22 May 2019 17:23:04 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id 505C481F0D; Wed, 22 May 2019 21:23:03 +0000 (UTC) Received: from krava (ovpn-204-104.brq.redhat.com [10.40.204.104]) by smtp.corp.redhat.com (Postfix) with SMTP id 824EF600C0; Wed, 22 May 2019 21:23:00 +0000 (UTC) Date: Wed, 22 May 2019 23:22:59 +0200 From: Jiri Olsa To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Adrian Hunter , lkml , Ingo Molnar , Namhyung Kim , Alexander Shishkin , Peter Zijlstra , Stanislav Fomichev , Song Liu , Andi Kleen Subject: Re: [PATCH 08/12] perf tools: Preserve eBPF maps when loading kcore Message-ID: <20190522212259.GA11325@krava> References: <20190508132010.14512-1-jolsa@kernel.org> <20190508132010.14512-9-jolsa@kernel.org> <20190522160657.GF30271@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190522160657.GF30271@kernel.org> User-Agent: Mutt/1.11.3 (2019-02-01) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Wed, 22 May 2019 21:23:03 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 22, 2019 at 01:06:57PM -0300, Arnaldo Carvalho de Melo wrote: > Em Wed, May 08, 2019 at 03:20:06PM +0200, Jiri Olsa escreveu: > > We need to preserve eBPF maps even if they are > > covered by kcore, because we need to access > > eBPF dso for source data. > > So, I reordered this one with the previous, as to get the output you > added to 07/12 we need what is in 08/12, and they are otherwise > completely independent, right? right jirka > > - Arnaldo > > > Adding map_groups__merge_in function to do that. > > It merges map into map_groups by splitting the > > new map within the existing map regions. > > > > Suggested-by: Adrian Hunter > > Link: http://lkml.kernel.org/n/tip-mlu13e9zl6rbsz4fa00x7mfa@git.kernel.org > > Signed-off-by: Jiri Olsa > > --- > > tools/perf/util/symbol.c | 97 ++++++++++++++++++++++++++++++++++++++-- > > 1 file changed, 93 insertions(+), 4 deletions(-) > > > > diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c > > index 5cbad55cd99d..29780fcd049c 100644 > > --- a/tools/perf/util/symbol.c > > +++ b/tools/perf/util/symbol.c > > @@ -1166,6 +1166,85 @@ static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data) > > return 0; > > } > > > > +/* > > + * Merges map into map_groups by splitting the new map > > + * within the existing map regions. > > + */ > > +static int map_groups__merge_in(struct map_groups *kmaps, struct map *new_map) > > +{ > > + struct map *old_map; > > + LIST_HEAD(merged); > > + > > + for (old_map = map_groups__first(kmaps); old_map; > > + old_map = map_groups__next(old_map)) { > > + > > + /* no overload with this one */ > > + if (new_map->end < old_map->start || > > + new_map->start >= old_map->end) > > + continue; > > + > > + if (new_map->start < old_map->start) { > > + /* > > + * |new...... > > + * |old.... > > + */ > > + if (new_map->end < old_map->end) { > > + /* > > + * |new......| -> |new..| > > + * |old....| -> |old....| > > + */ > > + new_map->end = old_map->start; > > + } else { > > + /* > > + * |new.............| -> |new..| |new..| > > + * |old....| -> |old....| > > + */ > > + struct map *m = map__clone(new_map); > > + > > + if (!m) > > + return -ENOMEM; > > + > > + m->end = old_map->start; > > + list_add_tail(&m->node, &merged); > > + new_map->start = old_map->end; > > + } > > + } else { > > + /* > > + * |new...... > > + * |old.... > > + */ > > + if (new_map->end < old_map->end) { > > + /* > > + * |new..| -> x > > + * |old.........| -> |old.........| > > + */ > > + map__put(new_map); > > + new_map = NULL; > > + break; > > + } else { > > + /* > > + * |new......| -> |new...| > > + * |old....| -> |old....| > > + */ > > + new_map->start = old_map->end; > > + } > > + } > > + } > > + > > + while (!list_empty(&merged)) { > > + old_map = list_entry(merged.next, struct map, node); > > + list_del_init(&old_map->node); > > + map_groups__insert(kmaps, old_map); > > + map__put(old_map); > > + } > > + > > + if (new_map) { > > + map_groups__insert(kmaps, new_map); > > + map__put(new_map); > > + } > > + return 0; > > +} > > + > > static int dso__load_kcore(struct dso *dso, struct map *map, > > const char *kallsyms_filename) > > { > > @@ -1222,7 +1301,12 @@ static int dso__load_kcore(struct dso *dso, struct map *map, > > while (old_map) { > > struct map *next = map_groups__next(old_map); > > > > - if (old_map != map) > > + /* > > + * We need to preserve eBPF maps even if they are > > + * covered by kcore, because we need to access > > + * eBPF dso for source data. > > + */ > > + if (old_map != map && !__map__is_bpf_prog(old_map)) > > map_groups__remove(kmaps, old_map); > > old_map = next; > > } > > @@ -1256,11 +1340,16 @@ static int dso__load_kcore(struct dso *dso, struct map *map, > > map_groups__remove(kmaps, map); > > map_groups__insert(kmaps, map); > > map__put(map); > > + map__put(new_map); > > } else { > > - map_groups__insert(kmaps, new_map); > > + /* > > + * Merge kcore map into existing maps, > > + * and ensure that current maps (eBPF) > > + * stay intact. > > + */ > > + if (map_groups__merge_in(kmaps, new_map)) > > + goto out_err; > > } > > - > > - map__put(new_map); > > } > > > > if (machine__is(machine, "x86_64")) { > > -- > > 2.20.1 > > -- > > - Arnaldo