From patchwork Fri Apr 9 10:39:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gerd Hoffmann X-Patchwork-Id: 12193649 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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 0638AC433B4 for ; Fri, 9 Apr 2021 10:40:52 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5720060230 for ; Fri, 9 Apr 2021 10:40:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5720060230 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:40296 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lUoZG-0003YL-5p for qemu-devel@archiver.kernel.org; Fri, 09 Apr 2021 06:40:50 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51360) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUoYL-00036i-DQ for qemu-devel@nongnu.org; Fri, 09 Apr 2021 06:39:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:25540) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUoYI-0007sN-IT for qemu-devel@nongnu.org; Fri, 09 Apr 2021 06:39:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617964788; 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: content-transfer-encoding:content-transfer-encoding; bh=3pMJ7hmjlE/xlyhraOCf3BJtgxCanyotf9XTSzKhnA0=; b=UB2FfvVOEsvra02qhCb+Ev1DUYJEyZaikC4fsQ0QqxhsxU5vW7yq3cB1+FtVFgESzlBeSN vqxesWUIysV9juu9zyC/oIOQL4BFXLQ5e0Ahf9oapkFHpgGPijyFiQcFtExbWJPRdVAV/c Nse4R4UXOOWupipbd0dVvk7M+h9Q500= 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-408-i8uKhoKhNziiYVXbaZhYjw-1; Fri, 09 Apr 2021 06:39:46 -0400 X-MC-Unique: i8uKhoKhNziiYVXbaZhYjw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3A434107ACC7 for ; Fri, 9 Apr 2021 10:39:45 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-114-165.ams2.redhat.com [10.36.114.165]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 52B3410023BE; Fri, 9 Apr 2021 10:39:38 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id 6E69018003A3; Fri, 9 Apr 2021 12:39:36 +0200 (CEST) From: Gerd Hoffmann To: qemu-devel@nongnu.org Subject: [PATCH] qemu-trace-stap: changing SYSTEMTAP_TAPSET considered harmful. Date: Fri, 9 Apr 2021 12:39:36 +0200 Message-Id: <20210409103936.369354-1-kraxel@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kraxel@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.133.124; envelope-from=kraxel@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gerd Hoffmann , Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Setting SYSTEMTAP_TAPSET to some value other than /usr/share/systemtap/tapsets results in systemtap not finding the standard tapset library any more, which in turn breaks tracing because pid() and other standard systemtap functions are not available any more. So using SYSTEMTAP_TAPSET to point systemtap to the qemu probes will only work for the prefix=/usr installs because both qemu and system tapsets in the same directory then. All other prefixes are broken. Fix that by using the "-I $tapsetdir" command line switch instead. Signed-off-by: Gerd Hoffmann --- scripts/qemu-trace-stap | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/scripts/qemu-trace-stap b/scripts/qemu-trace-stap index 90527eb974f4..0d0011cf396e 100755 --- a/scripts/qemu-trace-stap +++ b/scripts/qemu-trace-stap @@ -55,11 +55,6 @@ def tapset_dir(binary): return os.path.realpath(tapset) -def tapset_env(tapset_dir): - tenv = copy.copy(os.environ) - tenv["SYSTEMTAP_TAPSET"] = tapset_dir - return tenv - def cmd_run(args): prefix = probe_prefix(args.binary) tapsets = tapset_dir(args.binary) @@ -81,11 +76,11 @@ def cmd_run(args): # We request an 8MB buffer, since the stap default 1MB buffer # can be easily overflowed by frequently firing QEMU traces - stapargs = ["stap", "-s", "8"] + stapargs = ["stap", "-s", "8", "-I", tapsets ] if args.pid is not None: stapargs.extend(["-x", args.pid]) stapargs.extend(["-e", script]) - subprocess.call(stapargs, env=tapset_env(tapsets)) + subprocess.call(stapargs) def cmd_list(args):