From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f74.google.com (mail-wm1-f74.google.com [209.85.128.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8633717C21B for ; Fri, 3 Oct 2025 13:39:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759498742; cv=none; b=TaZn1c+PWaqI0URpNsnbj4S92PKjFefG5oYu8ZitJIwWW4QQBTPTfCeNDo6thGeQIkmzRKSLrwKrN57MHN4ITjCHMWXo8gMwkjwCW8xS+hhcQMvArrzZxhAricL/MSy50Xy+oj/fi9kxKGqdDLuMZCxcf5GekTniaAt9dwZigF4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759498742; c=relaxed/simple; bh=Axj9ASylM0oaMpSPEZroxhw8H/MRLAYh+XigJLXbiIg=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=qMC8lS4V9RuXUVH6Bz17+9lV8wkBWnZNTkHHa3RV1ahxNCTIZfA2+D79SwYu3FlbzjpQ4MmIeuKcUaJHjpL3D743ol2AwfGZ4v11HRdRB+GMQuGTsSYNkZMAI9WQCyFdSDuLI6rlda5yMSPh+LwXSV9iT3k4lAsPYKgVpaRVT+w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--vdonnefort.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=EQ1WSkI7; arc=none smtp.client-ip=209.85.128.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--vdonnefort.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="EQ1WSkI7" Received: by mail-wm1-f74.google.com with SMTP id 5b1f17b1804b1-46e4335fa87so12113985e9.0 for ; Fri, 03 Oct 2025 06:39:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1759498739; x=1760103539; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=bc6LimOXID+Bku1FEoRJ/EirmTeTKYklVJFEb8YK50Y=; b=EQ1WSkI76iMHAlNQe54SNrwp4z6XB7qf9T1+pwmGNkQTQL18oHoqlRH69FH7np1rtb ZWEEXQpNlktuFamKnAOImcwWC5I72DJ48TfoxKtjVBumayOZyqQILBjG+nWzZj7kM0YG 0r8a19FI5Adv0uRkzBxJcsVue+Ox2/cLyBx1AGXZ3ajdH0eb3mpTf5PD/6oMgyR/NEeA eZGMqy/wUyJfSz5v3cZO31sczXSzf2pwUIjT5PXz+unFOpTBkU1nklgQZANX5KPazNCs MwooH1VEv7cUK900BAbu+VyCHQpLeLXtff/3+GN39JA+KPP2TfwgJZKj7iAXJZHIVtsw aDAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1759498739; x=1760103539; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=bc6LimOXID+Bku1FEoRJ/EirmTeTKYklVJFEb8YK50Y=; b=U48DCI4lOqX/OCJoo+9MCcU/jCqDo1EXytVFNv5X7Jt1BiYrg2YXXbtWsMAZA7/Nxs S4NY/lP3X/4X2MMv3ZvsTIifjKiw85eWjYPIxZ1bHuBQHA1ooLCNTWM5qwnk/4HOtKyE ulcsw9tJRl1yIK655RudveIz9DPFe1XNkG3slIkSvcL+hXXANqPxsUuoaoxq+nc3RkDW 1CuD+N40ETA6fnDF2i7giyp3++5Qhoke82jmNF6m5WonA0rwTzuRabjR2kNvfS+wiKQv ngatGdBT287FeU/4MNBQat6NmaaagzZUcDFy41g07sDyPpZ+/NiUPWzDqbLzVohgBJbv yMrA== X-Forwarded-Encrypted: i=1; AJvYcCVxCu2d2EFOsmgDfspmq/WfIIbSGnRX9Gs7QCqfd6vZgbMujJKiTtNOCN61Ygv7ClFd86JI+G12/wu1ExyBXu0eJAg=@vger.kernel.org X-Gm-Message-State: AOJu0Ywb+usj481sb5nvUMhdgRFafrQFnsxOzaYTTLs4v2molRKKvz5t 8SwXCO0NmD4ddAy7len4KPsuGGqtjHNQE0Y3t9vJVduC/q9dG8ZPreqZ9K4ROM386RIWaU+dypF flMTVds/qzjdaWfeNq2hjiQ== X-Google-Smtp-Source: AGHT+IFA6VPDBbC1e+6gIWe9mwwubSc0dOt0/SMKjx4g1e9RJBwOm822bx7bReAGfXOd+prKSqJyKXuvGPwSOwjw X-Received: from wmbjv25.prod.google.com ([2002:a05:600c:5719:b0:46e:2640:aa83]) (user=vdonnefort job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:4fc8:b0:45b:7d77:b592 with SMTP id 5b1f17b1804b1-46e7110adfcmr22140975e9.12.1759498738728; Fri, 03 Oct 2025 06:38:58 -0700 (PDT) Date: Fri, 3 Oct 2025 14:37:59 +0100 In-Reply-To: <20251003133825.2068970-1-vdonnefort@google.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251003133825.2068970-1-vdonnefort@google.com> X-Mailer: git-send-email 2.51.0.618.g983fd99d29-goog Message-ID: <20251003133825.2068970-3-vdonnefort@google.com> Subject: [PATCH v7 02/28] ring-buffer: Store bpage pointers into subbuf_ids From: Vincent Donnefort To: rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-trace-kernel@vger.kernel.org, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com Cc: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, jstultz@google.com, qperret@google.com, will@kernel.org, aneesh.kumar@kernel.org, kernel-team@android.com, linux-kernel@vger.kernel.org, Vincent Donnefort Content-Type: text/plain; charset="UTF-8" The subbuf_ids field allows to point to a specific page from the ring-buffer based on its ID. As a preparation or the upcoming ring-buffer remote support, point this array to the buffer_page instead of the buffer_data_page. Signed-off-by: Vincent Donnefort diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 2c157cb86989..e5846f8f3c07 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -519,7 +519,7 @@ struct ring_buffer_per_cpu { unsigned int mapped; unsigned int user_mapped; /* user space mapping */ struct mutex mapping_lock; - unsigned long *subbuf_ids; /* ID to subbuf VA */ + struct buffer_page **subbuf_ids; /* ID to subbuf VA */ struct trace_buffer_meta *meta_page; struct ring_buffer_cpu_meta *ring_meta; @@ -7002,7 +7002,7 @@ static void rb_free_meta_page(struct ring_buffer_per_cpu *cpu_buffer) } static void rb_setup_ids_meta_page(struct ring_buffer_per_cpu *cpu_buffer, - unsigned long *subbuf_ids) + struct buffer_page **subbuf_ids) { struct trace_buffer_meta *meta = cpu_buffer->meta_page; unsigned int nr_subbufs = cpu_buffer->nr_pages + 1; @@ -7011,7 +7011,7 @@ static void rb_setup_ids_meta_page(struct ring_buffer_per_cpu *cpu_buffer, int id = 0; id = rb_page_id(cpu_buffer, cpu_buffer->reader_page, id); - subbuf_ids[id++] = (unsigned long)cpu_buffer->reader_page->page; + subbuf_ids[id++] = cpu_buffer->reader_page; cnt++; first_subbuf = subbuf = rb_set_head_page(cpu_buffer); @@ -7021,7 +7021,7 @@ static void rb_setup_ids_meta_page(struct ring_buffer_per_cpu *cpu_buffer, if (WARN_ON(id >= nr_subbufs)) break; - subbuf_ids[id] = (unsigned long)subbuf->page; + subbuf_ids[id] = subbuf; rb_inc_page(&subbuf); id++; @@ -7030,7 +7030,7 @@ static void rb_setup_ids_meta_page(struct ring_buffer_per_cpu *cpu_buffer, WARN_ON(cnt != nr_subbufs); - /* install subbuf ID to kern VA translation */ + /* install subbuf ID to bpage translation */ cpu_buffer->subbuf_ids = subbuf_ids; meta->meta_struct_len = sizeof(*meta); @@ -7186,13 +7186,15 @@ static int __rb_map_vma(struct ring_buffer_per_cpu *cpu_buffer, } while (p < nr_pages) { + struct buffer_page *subbuf; struct page *page; int off = 0; if (WARN_ON_ONCE(s >= nr_subbufs)) return -EINVAL; - page = virt_to_page((void *)cpu_buffer->subbuf_ids[s]); + subbuf = cpu_buffer->subbuf_ids[s]; + page = virt_to_page((void *)subbuf->page); for (; off < (1 << (subbuf_order)); off++, page++) { if (p >= nr_pages) @@ -7219,7 +7221,8 @@ int ring_buffer_map(struct trace_buffer *buffer, int cpu, struct vm_area_struct *vma) { struct ring_buffer_per_cpu *cpu_buffer; - unsigned long flags, *subbuf_ids; + struct buffer_page **subbuf_ids; + unsigned long flags; int err; if (!cpumask_test_cpu(cpu, buffer->cpumask)) @@ -7243,7 +7246,7 @@ int ring_buffer_map(struct trace_buffer *buffer, int cpu, if (err) return err; - /* subbuf_ids include the reader while nr_pages does not */ + /* subbuf_ids includes the reader while nr_pages does not */ subbuf_ids = kcalloc(cpu_buffer->nr_pages + 1, sizeof(*subbuf_ids), GFP_KERNEL); if (!subbuf_ids) { rb_free_meta_page(cpu_buffer); -- 2.51.0.618.g983fd99d29-goog