From nobody Tue Feb 10 20:14:39 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 AD87D33D516; Tue, 10 Feb 2026 08:43:46 +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=1770713026; cv=none; b=l97z3TdQ5jA/a90tUJr4MJegmMiEEzaCA3ewSro3ljKC4bw5lgjeMct4IrMnFCvf9p9ln1bCZg3d9SacuP9WfxiVirkg4E1FtLPPh3EWja392wTdOgcRppvMb1YSHKhEMDaoOeuJ45bZ8BgKIJx9+MMiprt7khQasgmCqm6Kdmk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770713026; c=relaxed/simple; bh=cCxCDeUbb8VZHuaRklOxBbrjGG/HQRFWUQIw/Qe0nCY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=eGPXRiTgYtMwZp990OqDIlJVXBol0Wfqz6BCBSUpGBPkzs0xYb6eDIzCCGBHhjFwuRbEVKqKGHLbulknfEgxijuP3OS7JL6tE5zrAt6BSLrS9idlWSI6690iIULdHNVjjiUFJQ2x0RnBpfjwQpd2aJRIDxJJNs3EGI0/CLd83KY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=m3mCnQOl; 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="m3mCnQOl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50A2EC116C6; Tue, 10 Feb 2026 08:43:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770713026; bh=cCxCDeUbb8VZHuaRklOxBbrjGG/HQRFWUQIw/Qe0nCY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m3mCnQOlaFrPPjCBbVIYCfh46HGGEpQJCEGmFhPnqMLFo+yYP2tPEJw9HVvSWvUZP Gcz731o0avsAElEP1Q0nNim0l3cx3RD1+TAYS3E6H+JXcyTCxhjs0+s6tvEQndYm9j G5VAvwkNKW/ELT+xN44kinxDCiUXNqzzy7rTx2Q1vIJLGc5zPWd/28InIHP+YduYgx jRs/seZmE5RVtEohjfYgoh5spyVzyibEZeg0ruK7u4fjBK9KV4qVGuN1WiZSsISd3g j4xSu9/2iePHl61H3TRFIhYBewW0kuFVZOCkcBvvDZ1XoOyiXRBPWHeUUqk7MD85Ai C3YtohPwL3eNw== 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 v8 2/6] tracing: Reset last_boot_info if ring buffer is reset Date: Tue, 10 Feb 2026 17:43:43 +0900 Message-ID: <177071302364.2293046.17895165659153977720.stgit@mhiramat.tok.corp.google.com> X-Mailer: git-send-email 2.53.0.239.g8d8fc8a987-goog In-Reply-To: <177071300558.2293046.12057922262682243630.stgit@mhiramat.tok.corp.google.com> References: <177071300558.2293046.12057922262682243630.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 fd470675809b..e884d32b7895 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;