From patchwork Fri Jan 24 09:23:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 233101 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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 91ADBC32771 for ; Fri, 24 Jan 2020 10:09:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 546C720709 for ; Fri, 24 Jan 2020 10:09:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579860558; bh=wntEDG+c2lrc7Y6TfsQfnENOdCTOx5P6x/a8KfAut9I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=sFQXVFhrkKt10TU/lRkSTMBUUFfNGWjyQ9vOHs/cgz90bbPjXWJ4MdQCAg/tYnG4x L1cjObb+IiMRT1bZN+J8F5v0p5KdWIpohNBjM7u+N+aPW5ijBC2rCVbW7LE4/flPV4 o+XRNy/iT8pwdXc7Cwz2/5ILZfwZGbwT5oQzMU6w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389429AbgAXKJO (ORCPT ); Fri, 24 Jan 2020 05:09:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:46084 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730613AbgAXKJO (ORCPT ); Fri, 24 Jan 2020 05:09:14 -0500 Received: from localhost (unknown [145.15.244.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 68A1A20709; Fri, 24 Jan 2020 10:09:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579860553; bh=wntEDG+c2lrc7Y6TfsQfnENOdCTOx5P6x/a8KfAut9I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D93a3cXy8823twqls7N/slaFLTVILTuaK1GCPHLxBiGjojGqRhcw2i4UfneS81CUl B8XWQw92+to2ugCVb723/7EF6RLgoBpXfmTygUqNeIRqiU9OhXmnIuxNmmtXHDLOCO AXy/7+OA5jGtDuRD+hcmjxUi0zG2Bzy51X8E1hKc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Adrian Hunter , Andi Kleen , Jiri Olsa , Namhyung Kim , Wang Nan , Arnaldo Carvalho de Melo Subject: [PATCH 4.19 013/639] perf map: No need to adjust the long name of modules Date: Fri, 24 Jan 2020 10:23:03 +0100 Message-Id: <20200124093048.769806203@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124093047.008739095@linuxfoundation.org> References: <20200124093047.008739095@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Arnaldo Carvalho de Melo commit f068435d9bb2d825d59e3c101bc579f09315ee01 upstream. At some point in the past we needed to make sure we would get the long name of modules and not just what we get from /proc/modules, but that need, as described in the cset that introduced the adjustment function: Fixes: c03d5184f0e9 ("perf machine: Adjust dso->long_name for offline module") Without using the buildid-cache: # lsmod | grep trusted # insmod trusted.ko # lsmod | grep trusted trusted 24576 0 # strace -e open,openat perf probe -m ./trusted.ko key_seal |& grep trusted openat(AT_FDCWD, "/sys/module/trusted/notes/.note.gnu.build-id", O_RDONLY) = 4 openat(AT_FDCWD, "/sys/module/trusted/notes/.note.gnu.build-id", O_RDONLY) = 7 openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/.debug/root/trusted.ko/dd3d355d567394d540f527e093e0f64b95879584/probes", O_RDWR|O_CREAT, 0644) = 3 openat(AT_FDCWD, "/usr/lib/debug/root/trusted.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/usr/lib/debug/root/trusted.ko", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/.debug/trusted.ko", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 openat(AT_FDCWD, "trusted.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, ".debug/trusted.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "trusted.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 4 openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 probe:key_seal (on key_seal in trusted) # perf probe -l probe:key_seal (on key_seal in trusted) # No attempt at opening '[trusted]'. Now using the build-id cache: # rmmod trusted # perf buildid-cache --add ./trusted.ko # insmod trusted.ko # strace -e open,openat perf probe -m ./trusted.ko key_seal |& grep trusted openat(AT_FDCWD, "/sys/module/trusted/notes/.note.gnu.build-id", O_RDONLY) = 4 openat(AT_FDCWD, "/sys/module/trusted/notes/.note.gnu.build-id", O_RDONLY) = 7 openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/.debug/root/trusted.ko/dd3d355d567394d540f527e093e0f64b95879584/probes", O_RDWR|O_CREAT, 0644) = 3 openat(AT_FDCWD, "/usr/lib/debug/root/trusted.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/usr/lib/debug/root/trusted.ko", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/.debug/trusted.ko", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 openat(AT_FDCWD, "trusted.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, ".debug/trusted.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "trusted.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 4 openat(AT_FDCWD, "/root/trusted.ko", O_RDONLY) = 3 # Again, no attempt at reading '[trusted]'. Finally, adding a probe to that function and then using: [root@quaco ~]# perf trace -e probe_perf:*/max-stack=16/ --max-events=2 0.000 perf/13456 probe_perf:dso__adjust_kmod_long_name(__probe_ip: 5492263) dso__adjust_kmod_long_name (/home/acme/bin/perf) machine__process_kernel_mmap_event (/home/acme/bin/perf) machine__process_mmap_event (/home/acme/bin/perf) perf_event__process_mmap (/home/acme/bin/perf) machines__deliver_event (/home/acme/bin/perf) perf_session__deliver_event (/home/acme/bin/perf) perf_session__process_event (/home/acme/bin/perf) process_simple (/home/acme/bin/perf) reader__process_events (/home/acme/bin/perf) __perf_session__process_events (/home/acme/bin/perf) perf_session__process_events (/home/acme/bin/perf) process_buildids (/home/acme/bin/perf) record__finish_output (/home/acme/bin/perf) __cmd_record (/home/acme/bin/perf) cmd_record (/home/acme/bin/perf) run_builtin (/home/acme/bin/perf) 0.055 perf/13456 probe_perf:dso__adjust_kmod_long_name(__probe_ip: 5492263) dso__adjust_kmod_long_name (/home/acme/bin/perf) machine__process_kernel_mmap_event (/home/acme/bin/perf) machine__process_mmap_event (/home/acme/bin/perf) perf_event__process_mmap (/home/acme/bin/perf) machines__deliver_event (/home/acme/bin/perf) perf_session__deliver_event (/home/acme/bin/perf) perf_session__process_event (/home/acme/bin/perf) process_simple (/home/acme/bin/perf) reader__process_events (/home/acme/bin/perf) __perf_session__process_events (/home/acme/bin/perf) perf_session__process_events (/home/acme/bin/perf) process_buildids (/home/acme/bin/perf) record__finish_output (/home/acme/bin/perf) __cmd_record (/home/acme/bin/perf) cmd_record (/home/acme/bin/perf) run_builtin (/home/acme/bin/perf) # This was the only path I could find using the perf tools that reach at this function, then as of november/2019, if we put a probe in the line where the actuall setting of the dso->long_name is done: # perf trace -e probe_perf:* ^C[root@quaco ~] # perf stat -e probe_perf:* -I 2000 2.000404265 0 probe_perf:dso__adjust_kmod_long_name 4.001142200 0 probe_perf:dso__adjust_kmod_long_name 6.001704120 0 probe_perf:dso__adjust_kmod_long_name 8.002398316 0 probe_perf:dso__adjust_kmod_long_name 10.002984010 0 probe_perf:dso__adjust_kmod_long_name 12.003597851 0 probe_perf:dso__adjust_kmod_long_name 14.004113303 0 probe_perf:dso__adjust_kmod_long_name 16.004582773 0 probe_perf:dso__adjust_kmod_long_name 18.005176373 0 probe_perf:dso__adjust_kmod_long_name 20.005801605 0 probe_perf:dso__adjust_kmod_long_name 22.006467540 0 probe_perf:dso__adjust_kmod_long_name ^C 23.683261941 0 probe_perf:dso__adjust_kmod_long_name # Its not being used at all. To further test this I used kvm.ko as the offline module, i.e. removed if from the buildid-cache by nuking it completely (rm -rf ~/.debug) and moved it from the normal kernel distro path, removed the modules, stoped the kvm guest, and then installed it manually, etc. # rmmod kvm-intel # rmmod kvm # lsmod | grep kvm # modprobe kvm-intel modprobe: ERROR: ctx=0x55d3b1722260 path=/lib/modules/5.3.8-200.fc30.x86_64/kernel/arch/x86/kvm/kvm.ko.xz error=No such file or directory modprobe: ERROR: ctx=0x55d3b1722260 path=/lib/modules/5.3.8-200.fc30.x86_64/kernel/arch/x86/kvm/kvm.ko.xz error=No such file or directory modprobe: ERROR: could not insert 'kvm_intel': Unknown symbol in module, or unknown parameter (see dmesg) # insmod ./kvm.ko # modprobe kvm-intel modprobe: ERROR: ctx=0x562f34026260 path=/lib/modules/5.3.8-200.fc30.x86_64/kernel/arch/x86/kvm/kvm.ko.xz error=No such file or directory modprobe: ERROR: ctx=0x562f34026260 path=/lib/modules/5.3.8-200.fc30.x86_64/kernel/arch/x86/kvm/kvm.ko.xz error=No such file or directory # lsmod | grep kvm kvm_intel 299008 0 kvm 765952 1 kvm_intel irqbypass 16384 1 kvm # # perf probe -x ~/bin/perf machine__findnew_module_map:12 mname=m.name:string filename=filename:string 'dso_long_name=map->dso->long_name:string' 'dso_name=map->dso->name:string' # perf probe -l probe_perf:machine__findnew_module_map (on machine__findnew_module_map:12@util/machine.c in /home/acme/bin/perf with mname filename dso_long_name dso_name) # perf record ^C[ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 3.416 MB perf.data (33956 samples) ] # perf trace -e probe_perf:machine* 6.322 perf/23099 probe_perf:machine__findnew_module_map(__probe_ip: 5492493, mname: "[salsa20_generic]", filename: "/lib/modules/5.3.8-200.fc30.x86_64/kernel/crypto/salsa20_generic.ko.xz", dso_long_name: "/lib/modules/5.3.8-200.fc30.x86_64/kernel/crypto/salsa20_generic.ko.xz", dso_name: "[salsa20_generic]") 6.375 perf/23099 probe_perf:machine__findnew_module_map(__probe_ip: 5492493, mname: "[kvm]", filename: "[kvm]", dso_long_name: "[kvm]", dso_name: "[kvm]") The filename doesn't come with the path, no point in trying to set the dso->long_name. [root@quaco ~]# strace -e open,openat perf probe -m ./kvm.ko kvm_apic_local_deliver |& egrep 'open.*kvm' openat(AT_FDCWD, "/sys/module/kvm_intel/notes/.note.gnu.build-id", O_RDONLY) = 4 openat(AT_FDCWD, "/sys/module/kvm/notes/.note.gnu.build-id", O_RDONLY) = 4 openat(AT_FDCWD, "/lib/modules/5.3.8-200.fc30.x86_64/kernel/arch/x86/kvm", O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_DIRECTORY) = 7 openat(AT_FDCWD, "/sys/module/kvm_intel/notes/.note.gnu.build-id", O_RDONLY) = 8 openat(AT_FDCWD, "/root/kvm.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/.debug/root/kvm.ko/5955f426cb93f03f30f3e876814be2db80ab0b55/probes", O_RDWR|O_CREAT, 0644) = 3 openat(AT_FDCWD, "/usr/lib/debug/root/kvm.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/usr/lib/debug/root/kvm.ko", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/.debug/kvm.ko", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/kvm.ko", O_RDONLY) = 3 openat(AT_FDCWD, "kvm.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, ".debug/kvm.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "kvm.ko.debug", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/root/kvm.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/kvm.ko", O_RDONLY) = 3 openat(AT_FDCWD, "/root/kvm.ko", O_RDONLY) = 4 openat(AT_FDCWD, "/root/kvm.ko", O_RDONLY) = 3 [root@quaco ~]# Cc: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-jlfew3lyb24d58egrp0o72o2@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/machine.c | 27 +-------------------------- 1 file changed, 1 insertion(+), 26 deletions(-) --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -681,24 +681,6 @@ int machine__process_switch_event(struct return 0; } -static void dso__adjust_kmod_long_name(struct dso *dso, const char *filename) -{ - const char *dup_filename; - - if (!filename || !dso || !dso->long_name) - return; - if (dso->long_name[0] != '[') - return; - if (!strchr(filename, '/')) - return; - - dup_filename = strdup(filename); - if (!dup_filename) - return; - - dso__set_long_name(dso, dup_filename, true); -} - struct map *machine__findnew_module_map(struct machine *machine, u64 start, const char *filename) { @@ -710,15 +692,8 @@ struct map *machine__findnew_module_map( return NULL; map = map_groups__find_by_name(&machine->kmaps, m.name); - if (map) { - /* - * If the map's dso is an offline module, give dso__load() - * a chance to find the file path of that module by fixing - * long_name. - */ - dso__adjust_kmod_long_name(map->dso, filename); + if (map) goto out; - } dso = machine__findnew_module_dso(machine, &m, filename); if (dso == NULL)