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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27DFCC0015E for ; Wed, 26 Jul 2023 13:42:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232583AbjGZNmW (ORCPT ); Wed, 26 Jul 2023 09:42:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50142 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229781AbjGZNmU (ORCPT ); Wed, 26 Jul 2023 09:42:20 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A55181738; Wed, 26 Jul 2023 06:42:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3438861A4F; Wed, 26 Jul 2023 13:42:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED80BC433C8; Wed, 26 Jul 2023 13:42:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690378937; bh=tYT9s1regzKdhNac5OTFo8gp2k+iHZup6mz8Z3GP1ko=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=aGMnS/iL2wMeDD8OkWa0vaTAfGMD7uJCTeZanQ4THjrj7+4R+mU0LrJWx7UOrGdhb ltnD9SeKmN6ttEc5HEtj2DfZtNsjYe8f8/e9XetDTWYkAJaHZbhhbL6o9gwkgdGclX QOf0VkCHeVGBmOOoXx5eo4l0barrKzF8oilB6NvRhOS4RMOO8vpJ4Kq2utrv/1Sn5f HFxu/mYpRcuH5xafYuP+nB/ODn4GIJKiUfzOy01imc6Y2CAx+7egj2lycm1iT5y9ei dI1ZIAywcjbGPoHMm1u8brTnqsIyLLnQdfef5pXArQ+GyI9Xh585xZBeojFnR6gdun 8brYPCSqIadPw== Date: Wed, 26 Jul 2023 22:42:13 +0900 From: Masami Hiramatsu (Google) To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Masami Hiramatsu , Mark Rutland , Andrew Morton Subject: Re: [PATCH v2 2/2] tracing: Add free_trace_iter_content() helper function Message-Id: <20230726224213.f5f3a23d207ffedeee291d22@kernel.org> In-Reply-To: <20230715141348.341887497@goodmis.org> References: <20230715141213.970003974@goodmis.org> <20230715141348.341887497@goodmis.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 15 Jul 2023 10:12:15 -0400 Steven Rostedt wrote: > From: "Steven Rostedt (Google)" > > As the trace iterator is created and used by various interfaces, the clean > up of it needs to be consistent. Create a free_trace_iter_content() helper > function that frees the content of the iterator and use that to clean it > up in all places that it is used. > > Signed-off-by: Steven Rostedt (Google) Looks good to me. Reviewed-by: Masami Hiramatsu (Google) BTW, this adds iter->fmt != static_fmt_buf check. Is it a kind of fix? Thank you, > --- > kernel/trace/trace.c | 33 ++++++++++++++++++++++----------- > 1 file changed, 22 insertions(+), 11 deletions(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 1c370ffbe062..8775930aa545 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -4815,6 +4815,25 @@ static const struct seq_operations tracer_seq_ops = { > .show = s_show, > }; > > +/* > + * Note, as iter itself can be allocated and freed in different > + * ways, this function is only used to free its content, and not > + * the iterator itself. The only requirement to all the allocations > + * is that it must zero all fields (kzalloc), as freeing works with > + * ethier allocated content or NULL. > + */ > +static void free_trace_iter_content(struct trace_iterator *iter) > +{ > + /* The fmt is either NULL, allocated or points to static_fmt_buf */ > + if (iter->fmt != static_fmt_buf) > + kfree(iter->fmt); > + > + kfree(iter->temp); > + kfree(iter->buffer_iter); > + mutex_destroy(&iter->mutex); > + free_cpumask_var(iter->started); > +} > + > static struct trace_iterator * > __tracing_open(struct inode *inode, struct file *file, bool snapshot) > { > @@ -4922,8 +4941,7 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot) > > fail: > mutex_unlock(&trace_types_lock); > - kfree(iter->temp); > - kfree(iter->buffer_iter); > + free_trace_iter_content(iter); > release: > seq_release_private(inode, file); > return ERR_PTR(-ENOMEM); > @@ -5002,11 +5020,7 @@ static int tracing_release(struct inode *inode, struct file *file) > > mutex_unlock(&trace_types_lock); > > - mutex_destroy(&iter->mutex); > - free_cpumask_var(iter->started); > - kfree(iter->fmt); > - kfree(iter->temp); > - kfree(iter->buffer_iter); > + free_trace_iter_content(iter); > seq_release_private(inode, file); > > return 0; > @@ -6763,10 +6777,7 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) > > mutex_unlock(&trace_types_lock); > > - free_cpumask_var(iter->started); > - kfree(iter->fmt); > - kfree(iter->temp); > - mutex_destroy(&iter->mutex); > + free_trace_iter_content(iter); > kfree(iter); > > trace_array_put(tr); > -- > 2.40.1 -- Masami Hiramatsu (Google)