From nobody Tue Feb 10 06:27:00 2026 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 A999D363C5F; Mon, 9 Feb 2026 09:25:34 +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=1770629134; cv=none; b=CqE136vuISATU7Kxs9Te9ikDCSeb0uXtHY7K4OJ8SfxWPD2JYxu7SnfFqFpXpqAaQnjuTKFz7KEmztYTOiBU0AQNyUyEjPS7dEnEMLjtpplXSgY+BeOYAVT1z6BtuQclpePPFdz6nhMETCRB4cN6xyGZsjqsgC8Fh5WOoHAut+Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770629134; c=relaxed/simple; bh=V/+j7kQfNuspu+Q5e0iTMIHqcYsXeUFZ+qYU0M2iJGQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=KZUFsDOa4mrmMuGbvF6YxxCqZU/i/jowextVh0sEwbFyNWoSuMOeQyCc5yNrCGHIvtnN0L4lUUuUX4DSExK/WIcGiISUddYFtbkJ8kyqGMApsT3r5+D2IRywrn9hU/8vV3I3HUm0qraoxotUlbsnAWfdGYvZKCVl6y630fS499w= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EKsv4lHq; 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="EKsv4lHq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8FCB6C2BC86; Mon, 9 Feb 2026 09:25:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770629134; bh=V/+j7kQfNuspu+Q5e0iTMIHqcYsXeUFZ+qYU0M2iJGQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EKsv4lHqhWxYHfQxsoPN2WTwixVhj63rnpYwDui9oX1oe3UqdakkXaU0Oee5+xN7G p0qJvE2ev3zfO0dMEtrN8qf6WQDx5eYbGG+BqkZJXDiqIuRH+b4tUTRLfB1ntCxvxC E9mPFfvCnTblnkXWL4LorDVCOqKstxoKdH0amhLwFr6YXf2fct2HaiGL1ugHpPwjkF bh6QJ2rdNf347yEH7y10xetucDFcj+o1uCaCM1fplNG/oEiuRejhEqdNR1GnO5DM77 6qgc76DWT6HLsql4uQz30DbyBzz1ZinFKcWsjqa49HByPteudyRPUuDjdiDSbzWsry Q2wI/GfQ/sBYw== From: "Masami Hiramatsu (Google)" To: Steven Rostedt Cc: Masami Hiramatsu , Mathieu Desnoyers , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH v7 1/4] tracing: Reset last_boot_info if ring buffer is reset Date: Mon, 9 Feb 2026 18:25:32 +0900 Message-ID: <177062913185.1230888.10201577470513915058.stgit@mhiramat.tok.corp.google.com> X-Mailer: git-send-email 2.53.0.239.g8d8fc8a987-goog In-Reply-To: <177062912135.1230888.17419570791737357433.stgit@mhiramat.tok.corp.google.com> References: <177062912135.1230888.17419570791737357433.stgit@mhiramat.tok.corp.google.com> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable From: Masami Hiramatsu (Google) Commit 32dc0042528d ("tracing: Reset last-boot buffers when reading out all cpu buffers") resets the last_boot_info when user read out all data via trace_pipe* files. But it is not reset when user resets the buffer from other files. (e.g. write `trace` file) Reset it when the corresponding ring buffer is reset too. Fixes: 32dc0042528d ("tracing: Reset last-boot buffers when reading out all= cpu buffers") Signed-off-by: Masami Hiramatsu (Google) --- Changes in v7: - Remove unneeded update_last_data_if_empty() call from tracing_snapshot_write() because snapshot is disabled on persistent instances. --- kernel/trace/trace.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 845b8a165daf..9e1cff78a1ca 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4127,6 +4127,8 @@ static int tracing_single_release_tr(struct inode *in= ode, struct file *file) return single_release(inode, file); } =20 +static bool update_last_data_if_empty(struct trace_array *tr); + static int tracing_open(struct inode *inode, struct file *file) { struct trace_array *tr =3D inode->i_private; @@ -4151,6 +4153,8 @@ static int tracing_open(struct inode *inode, struct f= ile *file) tracing_reset_online_cpus(trace_buf); else tracing_reset_cpu(trace_buf, cpu); + + update_last_data_if_empty(tr); } =20 if (file->f_mode & FMODE_READ) { @@ -5215,6 +5219,7 @@ tracing_set_trace_read(struct file *filp, char __user= *ubuf, int tracer_init(struct tracer *t, struct trace_array *tr) { tracing_reset_online_cpus(&tr->array_buffer); + update_last_data_if_empty(tr); return t->init(tr); } =20 @@ -7028,6 +7033,7 @@ int tracing_set_clock(struct trace_array *tr, const c= har *clockstr) ring_buffer_set_clock(tr->snapshot_buffer.buffer, trace_clocks[i].func); tracing_reset_online_cpus(&tr->snapshot_buffer); #endif + update_last_data_if_empty(tr); =20 if (tr->scratch && !(tr->flags & TRACE_ARRAY_FL_LAST_BOOT)) { struct trace_scratch *tscratch =3D tr->scratch;