From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=74.125.82.169 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793887384; b=LmWYdN45HNK/TH3nN3j5Vq2jwBBpFPRbyD/7ZOfTm0NT01/l5uP8Zi/010qZ7fioPVV4 CCy8TP/+rOccl2xCzjRTuRnxEOO6ABLAsHGhw1o/n69L8RVxxWC+LiLV8jpPpNpmqqxpx P/O1oYulo1nBKnAhA9ErVETDGYM2532X2cFGu5zNX4t2fttyoS8R/5Z0DL6jK3WpE5po2 5//yshDG6RlLjqg/sa1ZaO5gTtYE4AdpqKB4l+Bc9f/nPm2hLCluxcKMT5jDXijObk+kU Xgvg4M57WxNv3Zl6/bn+xLpft8DepE9O6P87vrOSfdmxbrop+C5ViYL+uLhS9M+BX9w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793887384; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: From:X-Google-Original-From:To:Cc:Subject:Date:Message-Id:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=OIhsjHfY+91mLh5ERTBbgCaSdhXDfj6pOLcBVrpf7dE=; b=tBM8yv+bFAcmHKYgVQgLt4SzaKlFul1g5widpcS+0m01hY6oJd6zmFlzbDDFW1MRdDxj lhT/iaH14PIlgvQG2Z7rAX7MmF581ZBfG5H6K+JMF2JOlQZ7Tu7KaLJuqke7NN/f8dr/g fftDSouYe6IG+T4jCExUqL40ZtkKJUWJ7KXdwCwS9jC6azszGsbOrALyCOMzLYMSvy7Nj hu/M264TohZqJUr4Dm6C6aqdkIFHm9zdHzIblkuDDWihPZctfw3LgSdDnz2P5uPuVymzd RkZLzGI1SBnL68TdcqcM8ZEsBWqHNbL5QB5QJ68+t4zNk74yXINRXLR8lR7cDZYcmHw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=ENP4g7uM; arc=none smtp.remote-ip=74.125.82.169 Received: from mail-dy1-f169.google.com (mail-dy1-f169.google.com [74.125.82.169]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CE7CA606A333 for ; Thu, 5 Nov 2026 14:03:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org CE7CA606A333 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=ENP4g7uM Received: by mail-dy1-f169.google.com with SMTP id 5a478bee46e88-36a1947498bso5396096eec.1 for ; Thu, 05 Nov 2026 06:03:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20260707; t=1793887383; x=1794492183; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=OIhsjHfY+91mLh5ERTBbgCaSdhXDfj6pOLcBVrpf7dE=; b=ENP4g7uMSMbYhu+BBPFSM+ov1cl3TLtkiv+NR5Zm9o66PfPSzGvWMAxPq1hEgdoAbj Q0u0gj0v5qXQl5pzvyMTkOvhMQsoPvda+9KglkcOwQeAWpghklVsQFGcXP2W7vs62Qat S8p2imnpd2cTIImdDGNX+4EquTWoMwOO4M4+rhTtKQAIjXx5D5VXDJXaJtFyMRiXuHo0 SI6/S/YoBs6X7ix120CCdosaLh9FynSQrs996AYrLRmSvNt8/ZPdtNzt//M68NxgezzS /a6I1t33fP5R8lu29JQzwRAZknEeyN457PJfOD+aOCTNXSrftL6/hq7F75HK9/0i3XQ/ vt9w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1793887383; x=1794492183; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=OIhsjHfY+91mLh5ERTBbgCaSdhXDfj6pOLcBVrpf7dE=; b=i2ZJ9/m0J+pcancajlivjDvP8ISwS0DGLCYUCb/sMdmv8PUjRy1WMA9NyNHTJwSh10 9hletZOuTG2AAsznZk3IATWZsXyuygldhz5eEKphe9M/TPVBRplZlG0+pkNuXDnkAbfZ bqAD32+/kN9s/QF22AFD3HKgt+GGYMSNsGnM4czgXNJiJkNPx/Piz1cD+2wys9DGYeJc wlpJ1sAgmchvefRsQLDNB9bDEQz/MJ2P4j0bmlxNgmsTYLkEda7ahPs3uLI9V6qgH04Y hIvw6todQR3E5MmbIj/Td7YXFL8RIM+rPO9oPnFgOYh55K+ON+hNkwTjHIKILFYoJBPN QnKg== X-Forwarded-Encrypted: i=1; AKwUvBz6jzVBpRPobTCTk1A4DdSQVPAzrDkVAQ3yqteJ1Sxl7XI0BST6SqeWEDITWwtTfHTh/BsU36FuMHQ40jx4hySUkfw=@vger.kernel.org X-Gm-Message-State: APuU4Z8O9hZxSZX9cR4m6qYz8TDSS+/RWlCu8OErENdjxWhQbFa+2yFr MnW5GsLEprcmx7N1XF41A42nEBQwdT0XjQ1nk/zxmTfB9YfSj90UKW1Q X-Gm-Gg: AYBFou24vyrVQ7bq90Hv/WdS2v/Fd1m7l7iSdOPGBqc66bDUnxZA/0Hjoo3abP5h4sy vEbR3O/coZZkU+yLeDjEGi5oHVbyCeP42gIBIEY4P/DJPF8xGrk7DgHA4tqFEAiSu4Rj04Pge7p sRcMCXjoV2CNMnM5P/+mB3pay+deFuN6JxVVsvPlEP+wQhCVSvYQwM2zB/Qm1Afu59S+kXH4wJp gPiy9jCniiNhnBspEGs64oTERAdLc/fittWowtLBbVQA4DUTOgIZliaSHnpgYhxbeIIDAhspT8/ suLg6AGWcOqLyEhUeMYOQjQWSS3NNM5xxdae4ZfcXtmkyPboLIkQBJ0CHr67YhgGKo4/RE88Dw9 l5hYilj2nuf12hBB3TZPDM6a+wFO0Pgiq4+IdihcpA3acTWTFUjDYMaxTMfzveaZmNZ715Kg78L f7vA0GF7dyel49ewNP+6BR6QvNoj8liXF0Ng8CVMwP0GhxQ8JCo8UtGfeznsgnOy0m9dsdAuOAk shCYvP/03jepcrVpm3DBdraUonVQNu+0EZOxHNCYqHEp/Bmgnwf1MfS41NOPiJln79gLwsZF41o H+qcuL3sihCIXSz1b0iacM7hCNGe3pSQRmunMq2Bxi36DxdsEiszd2fcbtLxAe63SS7PRQ== X-Received: by 2002:a05:701a:c907:b0:195:1a77:85f4 with SMTP id a92af1059eb24-1ac5ceee102mr26982844c88.24.1793887382662; Thu, 05 Nov 2026 06:03:02 -0800 (PST) Received: from bj-kjy-standalone-gaoxiang17.mioffice.cn ([43.224.245.230]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-36ca3981ff0sm20969616eec.24.2026.11.05.06.02.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Nov 2026 06:03:02 -0800 (PST) From: Xiang Gao X-Google-Original-From: Xiang Gao To: Steven Rostedt , Vincent Donnefort , Masami Hiramatsu , Donggeun Yoo Cc: Mathieu Desnoyers , Lorenzo Stoakes , gao xu , yinchuang1@xiaomi.com, linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, Xiang Gao Subject: [PATCH v5 3/4] tracing: add per-CPU buffer memory usage statistics Date: Thu, 5 Nov 2026 22:02:20 +0800 Message-Id: <20261105140221.44614-4-gaoxiang17@xiaomi.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20261105140221.44614-1-gaoxiang17@xiaomi.com> References: <20261105140221.44614-1-gaoxiang17@xiaomi.com> X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Provide a per-CPU view of the tracing ring-buffer memory usage under trace_stats/per_cpu/cpuN/memory_usage_kb, using the same categorized format as the aggregate file. Each file reports only the buffers belonging to that CPU. Signed-off-by: Xiang Gao --- kernel/trace/trace.c | 75 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 74 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 6036e368fe10..e7e23ff38105 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5898,6 +5898,60 @@ static const struct file_operations trace_mem_fops = { .release = single_release, }; +static struct trace_mem_stats trace_buffers_memory_cpu(int cpu) +{ + struct trace_mem_stats stats = {}; + struct trace_array *tr; + + guard(mutex)(&trace_types_lock); + + list_for_each_entry(tr, &ftrace_trace_arrays, list) + trace_array_buffer_memory(tr, cpu, &stats); + + /* Account for the bootstrapping temp_buffer as well. */ + if (temp_buffer) + stats.global += ring_buffer_memory_size(temp_buffer, cpu); + + stats.total_system = stats.global + stats.instances + + stats.snapshots + stats.remotes; + stats.total_carveout = stats.persistents; + + return stats; +} + +static int trace_mem_per_cpu_show(struct seq_file *m, void *v) +{ + struct trace_mem_stats stats = trace_buffers_memory_cpu((long)m->private); + + seq_printf(m, "global: %lu\n", stats.global >> 10); + seq_printf(m, "instances: %lu\n", stats.instances >> 10); + seq_printf(m, "snapshots: %lu\n", stats.snapshots >> 10); + seq_printf(m, "persistents: %lu\n", stats.persistents >> 10); + seq_printf(m, "remotes: %lu\n", stats.remotes >> 10); + seq_printf(m, "total_system: %lu\n", stats.total_system >> 10); + seq_printf(m, "total_carveout: %lu\n", stats.total_carveout >> 10); + + return 0; +} + +static int trace_mem_per_cpu_open(struct inode *inode, struct file *file) +{ + int ret; + + ret = tracing_check_open_get_tr(NULL); + if (ret) + return ret; + + return single_open(file, trace_mem_per_cpu_show, inode->i_private); +} + +static const struct file_operations trace_mem_per_cpu_fops = { + .open = trace_mem_per_cpu_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + #define LAST_BOOT_HEADER ((void *)1) static void *l_next(struct seq_file *m, void *v, loff_t *pos) @@ -9416,7 +9470,9 @@ static struct notifier_block trace_module_nb = { static __init void init_trace_stats_tracefs(void) { - struct dentry *stats_dir; + struct dentry *stats_dir, *per_cpu_dir, *cpu_dir; + char cpu_dir_name[30]; + int cpu; stats_dir = tracefs_create_dir("trace_stats", NULL); if (!stats_dir) @@ -9424,6 +9480,23 @@ static __init void init_trace_stats_tracefs(void) trace_create_file("memory_usage_kb", TRACE_MODE_READ, stats_dir, NULL, &trace_mem_fops); + + per_cpu_dir = tracefs_create_dir("per_cpu", stats_dir); + if (!per_cpu_dir) + return; + + for_each_tracing_cpu(cpu) { + snprintf(cpu_dir_name, 30, "cpu%d", cpu); + cpu_dir = tracefs_create_dir(cpu_dir_name, per_cpu_dir); + if (!cpu_dir) { + pr_warn("Could not create tracefs '%s' entry\n", + cpu_dir_name); + continue; + } + + trace_create_file("memory_usage_kb", TRACE_MODE_READ, cpu_dir, + (void *)(long)cpu, &trace_mem_per_cpu_fops); + } } static __init void tracer_init_tracefs_work_func(struct work_struct *work) -- 2.34.1