From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f73.google.com (mail-wr1-f73.google.com [209.85.221.73]) (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 7A7611F9F73 for ; Fri, 3 Oct 2025 13:39:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759498758; cv=none; b=jGEzzG1EZcZq2451HG10im4zSUsiyvAm9rvfGjB+l1q2QfQYcjb8r12hcNaLLvYdxee5pEqCsMJksnfZGm2BAmOc1MIxfqv/JAxqdTvhpUYm+GtJ36hSn7OGTtvL06pIDnhfN1inEfI9MjriG2LWYyflRG0SZoJecSIvEGgWM44= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759498758; c=relaxed/simple; bh=3Gyq8aA8JN0nK+7FXBMD7LVv1KmJh45YjAAyxT/uPCw=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=L0Jcat+nudyZLQQm4x+d9x5uBVizXN8sLkRYU2vr9/jfua8Bxd+in9S8OJug+5lrPiLlCqVMjQu1k5kxBWFMrvN6Tc/RGHzAw5W+E20GkqJBnqGHABY7N6GL5ECkFb9SvGAXDxm2Df0p85PvqraqJkzLJF9gS1uhkFKkX8U/EN4= 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=Lao6h/qg; arc=none smtp.client-ip=209.85.221.73 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="Lao6h/qg" Received: by mail-wr1-f73.google.com with SMTP id ffacd0b85a97d-401dbafbcfaso1446369f8f.1 for ; Fri, 03 Oct 2025 06:39:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1759498753; x=1760103553; 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=cusWrm7Pe7Vzh2zNqiDKt7LKbdzyFf6LREbhhod2FBw=; b=Lao6h/qgwbSPXuxKRlQhRIR+tILvaqUoMprgAexnGedblVpa3CqYF8Fllpf4YNE0ne zxeC2+EtY+F7UKlzUXri18vu/fc5k4dTJ4RXC8zq6vfYV0L5UzWiF7NTC8aQNIdI1RSF yteLmgrsQ66+wrypH27mbdiLTy2x7uTjxFUsMSMM+Um/O4VXZwElcxVRRcmbzLMnypAx fiefd5DAgpTQv4UY8MJ/vbnxq79Vty4PwWgruSVx5BagU8qoQ2/3fS1rDBA9K47qFLrQ L/XJYLpdmLLFALw5A3ANZuNSa883W9ABoK3TJw0Jdjniu9Pwo/jrfNPf5xMenJeg7wDc UkAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1759498753; x=1760103553; 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=cusWrm7Pe7Vzh2zNqiDKt7LKbdzyFf6LREbhhod2FBw=; b=fiQtRRezI1Q2lEnPgoLxyB20iUziiFvWrJuIOus5gDPNoAQ+XtEFEWpkNMK8za3X+5 OdX1oM6sbXE/lUr7QSdyoQWhnMR/zvoLFMlToLLQyfsfZpKPUWzEXKIDrh6E3spLdgij YToW+/oEc6+pvvQ76MbJMPI8aVYigJkwQrkm63nnw1eEyYnCGAewQKzfCuVbV+swwbBZ qoLRqE5JFF3ATTeuED2TbppHEm58k2NwJYUoMSJ3VJfsfIc7tqkqbm5FSAqBsQ3UThLi J8PhoIvezAEu0RR/Ua0mO4wzvN8j0WJaex1KoMRxwDUaUf1+8/vAEEyiPfBw5JKM6aSU WeUA== X-Forwarded-Encrypted: i=1; AJvYcCW93koAMSqOBXx3wladqFoKDwrrtc7wC7CeZEJ3BvCAvckMhfvsiaeRMgpBpkv0KmvgRT1Q5EUs3y5eaoJU60Y7THw=@vger.kernel.org X-Gm-Message-State: AOJu0YyqEwFkj3rarjOnlzg+CvO21k/35VXRBt75NO9ELUAkHxc8kzVk VBzypcd0UuD//bwYuumVrWdnKkqe/3JdMsDZo5wgqUWYdC5Iuei/xgiEtdfTqXz82kCk0C6YlGg 5kJU+9XTMrLhE7S9P0piGhQ== X-Google-Smtp-Source: AGHT+IF6GiKCqwKfjKEeuxZgNsXAZSGVRxvCwcB1YwHTIPjTMo5AijDWEtVQrQi9EZhBvqgSIyLZKQ4QheeyH+xU X-Received: from wmby13.prod.google.com ([2002:a05:600c:c04d:b0:46e:3771:b9c9]) (user=vdonnefort job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6000:18a9:b0:404:ac77:6598 with SMTP id ffacd0b85a97d-4256713ac9dmr2185339f8f.11.1759498753278; Fri, 03 Oct 2025 06:39:13 -0700 (PDT) Date: Fri, 3 Oct 2025 14:38:14 +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: <20251003133825.2068970-18-vdonnefort@google.com> Subject: [PATCH v7 17/28] tracing: load/unload page callbacks for simple_ring_buffer 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" Add load/unload callback used for each admitted page in the ring-buffer. This will be later useful for the pKVM hypervisor which uses a different VA space and need to dynamically map/unmap the ring-buffer pages. Signed-off-by: Vincent Donnefort diff --git a/include/linux/simple_ring_buffer.h b/include/linux/simple_ring_buffer.h index f324df2f875b..ecd0e988c699 100644 --- a/include/linux/simple_ring_buffer.h +++ b/include/linux/simple_ring_buffer.h @@ -110,4 +110,11 @@ int simple_ring_buffer_reset(struct simple_rb_per_cpu *cpu_buffer); */ int simple_ring_buffer_swap_reader_page(struct simple_rb_per_cpu *cpu_buffer); +int __simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, + struct simple_buffer_page *bpages, + const struct ring_buffer_desc *desc, + void *(*load_page)(unsigned long va), + void (*unload_page)(void *va)); +void __simple_ring_buffer_unload(struct simple_rb_per_cpu *cpu_buffer, + void (*unload_page)(void *)); #endif diff --git a/kernel/trace/simple_ring_buffer.c b/kernel/trace/simple_ring_buffer.c index 20e3cd6071a2..c2ec6017c37c 100644 --- a/kernel/trace/simple_ring_buffer.c +++ b/kernel/trace/simple_ring_buffer.c @@ -71,7 +71,7 @@ static void simple_bpage_reset(struct simple_buffer_page *bpage) local_set(&bpage->page->commit, 0); } -static void simple_bpage_init(struct simple_buffer_page *bpage, unsigned long page) +static void simple_bpage_init(struct simple_buffer_page *bpage, void *page) { INIT_LIST_HEAD(&bpage->link); bpage->page = (struct buffer_data_page *)page; @@ -338,10 +338,15 @@ int simple_ring_buffer_reset(struct simple_rb_per_cpu *cpu_buffer) return 0; } -int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct simple_buffer_page *bpages, - const struct ring_buffer_desc *desc) +int __simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, + struct simple_buffer_page *bpages, + const struct ring_buffer_desc *desc, + void *(*load_page)(unsigned long va), + void (*unload_page)(void *va)) { struct simple_buffer_page *bpage = bpages; + int ret = 0; + void *page; int i; /* At least 1 reader page and two pages in the ring-buffer */ @@ -350,15 +355,22 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct simple_ memset(cpu_buffer, 0, sizeof(*cpu_buffer)); - cpu_buffer->bpages = bpages; + cpu_buffer->meta = load_page(desc->meta_va); + if (!cpu_buffer->meta) + return -EINVAL; - cpu_buffer->meta = (void *)desc->meta_va; memset(cpu_buffer->meta, 0, sizeof(*cpu_buffer->meta)); cpu_buffer->meta->meta_page_size = PAGE_SIZE; cpu_buffer->meta->nr_subbufs = cpu_buffer->nr_pages; /* The reader page is not part of the ring initially */ - simple_bpage_init(bpage, desc->page_va[0]); + page = load_page(desc->page_va[0]); + if (!page) { + unload_page(cpu_buffer->meta); + return -EINVAL; + } + + simple_bpage_init(bpage, page); bpage->id = 0; cpu_buffer->nr_pages = 1; @@ -368,7 +380,13 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct simple_ cpu_buffer->head_page = bpage + 1; for (i = 1; i < desc->nr_page_va; i++) { - simple_bpage_init(++bpage, desc->page_va[i]); + page = load_page(desc->page_va[i]); + if (!page) { + ret = -EINVAL; + break; + } + + simple_bpage_init(++bpage, page); bpage->link.next = &(bpage + 1)->link; bpage->link.prev = &(bpage - 1)->link; @@ -377,6 +395,14 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct simple_ cpu_buffer->nr_pages = i + 1; } + if (ret) { + for (i--; i >= 0; i--) + unload_page((void *)desc->page_va[i]); + unload_page(cpu_buffer->meta); + + return ret; + } + /* Close the ring */ bpage->link.next = &cpu_buffer->tail_page->link; cpu_buffer->tail_page->link.prev = &bpage->link; @@ -384,19 +410,46 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct simple_ /* The last init'ed page points to the head page */ simple_bpage_set_head_link(bpage); + cpu_buffer->bpages = bpages; + return 0; } -void simple_ring_buffer_unload(struct simple_rb_per_cpu *cpu_buffer) +static void *__load_page(unsigned long page) { + return (void *)page; +} + +static void __unload_page(void *page) { } + +int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct simple_buffer_page *bpages, + const struct ring_buffer_desc *desc) +{ + return __simple_ring_buffer_init(cpu_buffer, bpages, desc, __load_page, __unload_page); +} + +void __simple_ring_buffer_unload(struct simple_rb_per_cpu *cpu_buffer, + void (*unload_page)(void *)) +{ + int p; + if (!simple_rb_loaded(cpu_buffer)) return; simple_rb_enable_tracing(cpu_buffer, false); + unload_page(cpu_buffer->meta); + for (p = 0; p < cpu_buffer->nr_pages; p++) + unload_page(cpu_buffer->bpages[p].page); + cpu_buffer->bpages = NULL; } +void simple_ring_buffer_unload(struct simple_rb_per_cpu *cpu_buffer) +{ + return __simple_ring_buffer_unload(cpu_buffer, __unload_page); +} + int simple_ring_buffer_enable_tracing(struct simple_rb_per_cpu *cpu_buffer, bool enable) { if (!simple_rb_loaded(cpu_buffer)) -- 2.51.0.618.g983fd99d29-goog