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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id A1015E732D0 for ; Thu, 28 Sep 2023 13:47:27 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qlrJl-00011t-2j; Thu, 28 Sep 2023 09:44:37 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qlrJe-0000vE-EX for qemu-devel@nongnu.org; Thu, 28 Sep 2023 09:44:30 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qlrJb-0005H6-R2 for qemu-devel@nongnu.org; Thu, 28 Sep 2023 09:44:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1695908666; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Ra4SiqIZX5+1ZMDMrjsmfd3AXlb8bNimdMX7saAN+BQ=; b=gFSji/cftaL5TR1VgIqM1p/Db6ZGVtACMu3sTNCxnwVWq5EQc7FVlxwIwOJ9OlAZ9zvfyW LvhVgHrwuTdQ7Bk9pvFuhhbzkEpGSN0J/bX74wy2e+p+jWRixBz1nm1HB9n4lG1lzv5lbY 1SpQGPzmcldnGQc8O8mHchvtxKHxjKc= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-209-ICON1eygOvea_VgqUOOskA-1; Thu, 28 Sep 2023 09:44:24 -0400 X-MC-Unique: ICON1eygOvea_VgqUOOskA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 376398002B2; Thu, 28 Sep 2023 13:44:24 +0000 (UTC) Received: from localhost (unknown [10.39.195.26]) by smtp.corp.redhat.com (Postfix) with ESMTP id BB379100650B; Thu, 28 Sep 2023 13:44:23 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Mads Ynddal , John Snow , Cleber Rosa , Mads Ynddal , Stefan Hajnoczi Subject: [PULL 08/14] simpletrace: made Analyzer into context-manager Date: Thu, 28 Sep 2023 09:44:01 -0400 Message-ID: <20230928134407.568453-9-stefanha@redhat.com> In-Reply-To: <20230928134407.568453-1-stefanha@redhat.com> References: <20230928134407.568453-1-stefanha@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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_NONE=-0.0001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Mads Ynddal Instead of explicitly calling `begin` and `end`, we can change the class to use the context-manager paradigm. This is mostly a styling choice, used in modern Python code. But it also allows for more advanced analyzers to handle exceptions gracefully in the `__exit__` method (not demonstrated here). Reviewed-by: Stefan Hajnoczi Signed-off-by: Mads Ynddal Message-id: 20230926103436.25700-9-mads@ynddal.dk Signed-off-by: Stefan Hajnoczi --- scripts/simpletrace.py | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) diff --git a/scripts/simpletrace.py b/scripts/simpletrace.py index 229b10aa99..7f514d1577 100755 --- a/scripts/simpletrace.py +++ b/scripts/simpletrace.py @@ -122,12 +122,13 @@ def read_trace_records(event_mapping, event_id_to_name, fobj): yield rec -class Analyzer(object): +class Analyzer: """A trace file analyzer which processes trace records. An analyzer can be passed to run() or process(). The begin() method is invoked, then each trace record is processed, and finally the end() method - is invoked. + is invoked. When Analyzer is used as a context-manager (using the `with` + statement), begin() and end() are called automatically. If a method matching a trace event name exists, it is invoked to process that trace record. Otherwise the catchall() method is invoked. @@ -165,6 +166,15 @@ def end(self): """Called at the end of the trace.""" pass + def __enter__(self): + self.begin() + return self + + def __exit__(self, exc_type, exc_val, exc_tb): + if exc_type is None: + self.end() + return False + def process(events, log, analyzer, read_header=True): """Invoke an analyzer on each event in a log. Args: @@ -226,15 +236,14 @@ def build_fn(analyzer, event): # Just arguments, no timestamp or pid return lambda _, rec: fn(*rec[3:3 + event_argcount]) - analyzer.begin() - fn_cache = {} - for rec in read_trace_records(event_mapping, event_id_to_name, log): - event_num = rec[0] - event = event_mapping[event_num] - if event_num not in fn_cache: - fn_cache[event_num] = build_fn(analyzer, event) - fn_cache[event_num](event, rec) - analyzer.end() + with analyzer: + fn_cache = {} + for rec in read_trace_records(event_mapping, event_id_to_name, log): + event_num = rec[0] + event = event_mapping[event_num] + if event_num not in fn_cache: + fn_cache[event_num] = build_fn(analyzer, event) + fn_cache[event_num](event, rec) if close_log: log.close() -- 2.41.0