From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2F7BB17562; Wed, 24 Jan 2024 15:11:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706109119; cv=none; b=bD0J18j/pDfEim7PM0OaKm6O6Z3VusD4whdohbB/J6tX9rhoPpbwZOwL1WeU+PCYAUXebdGkRiOE0PcBZDE7bN55+2VvYSbc9IsC8ThYM1UwNNAjY6VaLpdpI5Kh2pixaY4MlB7k0pgWgDVJxjOEKanFNs2LTFX7bOZOL8toWaA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706109119; c=relaxed/simple; bh=R89RbMLDlTyyQD/EW+3r2qZaBZKEVWRsol+oOTF+Puo=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=n3svRxU7sAbjVPgy0RkNyhvW6vt1FJMvr6IwyV++IFrUqFOUVqCXGtpkmig1wg5OKJ99DebJ+Vdkwwp5HAJYFk5108P/3RbzXBUHogRB5ceMhRE4v50SuMcVWl8bXrz9fJU3SeiFlj2YgDEgTo+ilpHJDeCkHya8eT2hGYeTnVk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TW6p4XCR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TW6p4XCR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C012FC433C7; Wed, 24 Jan 2024 15:11:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706109118; bh=R89RbMLDlTyyQD/EW+3r2qZaBZKEVWRsol+oOTF+Puo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=TW6p4XCR71WvsUtJAPzVLicpm72SL/R5SDZMWmzplbHW8PGdjRxsPF8cg+Js/a5o7 XcbOnnGhx0wYlF/N0e/pIBZ1e9oa1NUxRLerZg02RlgAjagm1iQgstlHb/HPQhqwUZ 52YDJoRbW0eGJ4LMts9YAfEmKMKN40jAyLbTEs3cTJp2XIRLl4W3WwHXJ9ge36wEJl 129d5iuzkYp9geKzVMrJQu7+BOynst7FkaXCrdj/iaIqUkkaV0achD57B+tRQj7S7X +DvOkGiLzmtZScwyN0/Jk+HndIOPtPxxbWdo5bCd1Hsn7pR7g19hyvpwilYfL0oYfc I6sWxyPi0+FIA== Date: Thu, 25 Jan 2024 00:11:49 +0900 From: Masami Hiramatsu (Google) To: Vincent Donnefort Cc: rostedt@goodmis.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, mathieu.desnoyers@efficios.com, kernel-team@android.com Subject: Re: [PATCH v12 3/6] tracing: Add snapshot refcount Message-Id: <20240125001149.364c0b08237e8b7f0a69bd56@kernel.org> In-Reply-To: <20240123110757.3657908-4-vdonnefort@google.com> References: <20240123110757.3657908-1-vdonnefort@google.com> <20240123110757.3657908-4-vdonnefort@google.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Tue, 23 Jan 2024 11:07:54 +0000 Vincent Donnefort wrote: [...] > @@ -6592,8 +6641,11 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) > > if (t->init) { > ret = tracer_init(t, tr); > - if (ret) > + if (ret) { > + if (t->use_max_tr) > + tracing_disarm_snapshot_locked(tr); This part is out of CONFIG_TRACER_MAX_TRACE, so it may cause a compile error if CONFIG_TRACER_MAX_TRACE is not set. > goto out; > + } > } > > tr->current_trace = t; [...] > diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c > index 46439e3bcec4..d41bf64741e2 100644 > --- a/kernel/trace/trace_events_trigger.c > +++ b/kernel/trace/trace_events_trigger.c > @@ -597,20 +597,9 @@ static int register_trigger(char *glob, > return ret; > } > > -/** > - * unregister_trigger - Generic event_command @unreg implementation > - * @glob: The raw string used to register the trigger > - * @test: Trigger-specific data used to find the trigger to remove > - * @file: The trace_event_file associated with the event > - * > - * Common implementation for event trigger unregistration. > - * > - * Usually used directly as the @unreg method in event command > - * implementations. > - */ > -static void unregister_trigger(char *glob, > - struct event_trigger_data *test, > - struct trace_event_file *file) OK, so __unregister_trigger returns true if data exists, but unregister_trigger() ignores results. (I want some comment here) > +static bool __unregister_trigger(char *glob, > + struct event_trigger_data *test, > + struct trace_event_file *file) > { > struct event_trigger_data *data = NULL, *iter; > > @@ -626,8 +615,32 @@ static void unregister_trigger(char *glob, > } > } > > - if (data && data->ops->free) > - data->ops->free(data); > + if (data) { > + if (data->ops->free) > + data->ops->free(data); > + > + return true; > + } > + > + return false; > +} > + > +/** > + * unregister_trigger - Generic event_command @unreg implementation > + * @glob: The raw string used to register the trigger > + * @test: Trigger-specific data used to find the trigger to remove > + * @file: The trace_event_file associated with the event > + * > + * Common implementation for event trigger unregistration. > + * > + * Usually used directly as the @unreg method in event command > + * implementations. > + */ > +static void unregister_trigger(char *glob, > + struct event_trigger_data *test, > + struct trace_event_file *file) > +{ > + __unregister_trigger(glob, test, file); > } > > /* > @@ -1470,12 +1483,20 @@ register_snapshot_trigger(char *glob, > struct event_trigger_data *data, > struct trace_event_file *file) > { > - if (tracing_alloc_snapshot_instance(file->tr) != 0) > + if (tracing_arm_snapshot(file->tr)) > return 0; BTW, is this return value correct? It seems that the register_*_trigger() will return error code when it fails. Thanks, > > return register_trigger(glob, data, file); > } > > +static void unregister_snapshot_trigger(char *glob, > + struct event_trigger_data *data, > + struct trace_event_file *file) > +{ > + if (__unregister_trigger(glob, data, file)) > + tracing_disarm_snapshot(file->tr); > +} > + > static int > snapshot_trigger_print(struct seq_file *m, struct event_trigger_data *data) > { > @@ -1508,7 +1529,7 @@ static struct event_command trigger_snapshot_cmd = { > .trigger_type = ETT_SNAPSHOT, > .parse = event_trigger_parse, > .reg = register_snapshot_trigger, > - .unreg = unregister_trigger, > + .unreg = unregister_snapshot_trigger, > .get_trigger_ops = snapshot_get_trigger_ops, > .set_filter = set_trigger_filter, > }; > -- > 2.43.0.429.g432eaa2c6b-goog > -- Masami Hiramatsu (Google)