From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f74.google.com (mail-ej1-f74.google.com [209.85.218.74]) (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 173E928A72F for ; Tue, 6 May 2025 16:49:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746550155; cv=none; b=lxuwn9WMLpWtYkXb+4xaidcBeD9XwIKnSLKdvFXyTQ8hYbuZsyfkYr21SUQWvTtomqTrvwAbGJs/OfaeK2oeJtSSnGz7chfcDHRX4M48y25lvdQEtkwBY41sEAN0B/ocK9eKN1qVqrDAua6fFW0WJLD3Ahovj5zQ+HxoohtBYUY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746550155; c=relaxed/simple; bh=NVCqxcX7WnR7NqGIbz8oFzTlAHuhz7dhxcMS39AX+eI=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=NEsIVdH0sfCs8vk09FSefVI/IecQgqq4miLFfkYowDskGsGOQ3NzNmbWVHEMQVDIXdNpQN15dFA5pWnpa6Mmu5/bTjzkYuJmUtw2Hq/dhKpKg9yfHXT0DNwFqck8iaKEVWjmCd5YKdxh4AtRGvh2VdxRXEMlcxJUQTIa00iIWGo= 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=Il1KIayh; arc=none smtp.client-ip=209.85.218.74 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="Il1KIayh" Received: by mail-ej1-f74.google.com with SMTP id a640c23a62f3a-ac28f255a36so384639466b.3 for ; Tue, 06 May 2025 09:49:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1746550151; x=1747154951; 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=PbofLrSiYoUrDKR0IcYz2ighpQm3HY6HT+wQFKaRR8E=; b=Il1KIayhPT5rRB2q6JvQwA66EaodRYk+1h05r8cs8doSqw5V4Tisn0JmEidr4Crx5g yxuuNeeOpBYpb8vgcU0NLPHKPYsMVA8oL2kA7TPE5T0zCeh6hMnpXY816hmxPrs9KrDV BHIM4NuXOXbT5kfanYfX4e20bemQV9xIZq6JWSo1Jrao4LWZz8/v2HAVBJYZq3x+N6pl u6bikBmB7sdGj/erIeZ9dq+SQ8NjCRlHZ1/nXTldN3+JNt6Vmd73lZY3m29tjzGVYXC1 qpdaeEA4bMVjbcOGFhLhQEO03YnrgWlahF3t+IExV74uvO3B6ll1JtCRYHwFA25T2yo+ CFIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1746550151; x=1747154951; 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=PbofLrSiYoUrDKR0IcYz2ighpQm3HY6HT+wQFKaRR8E=; b=d5gQ13qZCup9FubS/wZ/GkYoM/vnaO/FLEy93AGBMsPKwvjs0RnE6fvXPwhHPst+FX P9PZepyOw33Ii9JAXq/1jwTCZGqICjAfjeayks9iYsA1SYkkEwAfqYj5+WWpEdrj2Gbq gdevl49vqQyRO5WRmDum1/gC1qyvVE1tBjG8ISerqbXFt+bNagE9uQatw1kflLdmZc9J kjVmaOjfxlzKDbVcAwME3sQutFSxzR44uiooFSCgdcFdjl2O6r6pHzNTGjZ4KjFTZZNh L0CGRNYAIEm8qcMan/Q2cL3AgU6CXQbUhXHKyIVomYDU54YvZOWgAi2VKAf2VReRxUVJ SkMg== X-Forwarded-Encrypted: i=1; AJvYcCWdYkEYTAxZ7OvScB8Vbje/CHolzLP6RKjhhyNKSbHVOAXRYZXU2RKGsuWO45vHjkm/rky7n2BdCi+gsmRu90X88N4=@vger.kernel.org X-Gm-Message-State: AOJu0Yze8T4MxbRxr1vX5pdN/hVqbg6extSoEAfncns3VckbpCkHoJuU jkTicXs4sjXseHvq5eNkIE2RYFCKUMs0CEaiCnfr096Gqj7fqBqvndPtsBf/qfgld2QgfLhSdN4 85k/vd9G/3wrZy43qng== X-Google-Smtp-Source: AGHT+IGGoAXb1vdJDEqbvbocLN2nVo70zjIZSaJaSUPxR2r33LndiIC/nG5doi1ZsnzpfOo5CHFpJEQ9HbbmWv/E X-Received: from wmbhc5.prod.google.com ([2002:a05:600c:8705:b0:43d:9035:df36]) (user=vdonnefort job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:698e:b0:43d:7588:6688 with SMTP id 5b1f17b1804b1-441c48b672emr115738045e9.12.1746550141291; Tue, 06 May 2025 09:49:01 -0700 (PDT) Date: Tue, 6 May 2025 17:48:08 +0100 In-Reply-To: <20250506164820.515876-1-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: <20250506164820.515876-1-vdonnefort@google.com> X-Mailer: git-send-email 2.49.0.967.g6a0df3ecc3-goog Message-ID: <20250506164820.515876-13-vdonnefort@google.com> Subject: [PATCH v4 12/24] 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, 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 6cf8486d46e2..10e385d347a0 100644 --- a/include/linux/simple_ring_buffer.h +++ b/include/linux/simple_ring_buffer.h @@ -46,4 +46,12 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct simple_ int simple_ring_buffer_enable_tracing(struct simple_rb_per_cpu *cpu_buffer, bool enable); int simple_ring_buffer_swap_reader_page(struct simple_rb_per_cpu *cpu_buffer); int simple_ring_buffer_reset(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 da9ea42b9926..54c8f221f693 100644 --- a/kernel/trace/simple_ring_buffer.c +++ b/kernel/trace/simple_ring_buffer.c @@ -55,7 +55,7 @@ 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->list); bpage->page = (struct buffer_data_page *)page; @@ -282,10 +282,14 @@ 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 one head */ @@ -294,15 +298,22 @@ 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; @@ -312,7 +323,13 @@ 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->list.next = &(bpage + 1)->list; bpage->list.prev = &(bpage - 1)->list; @@ -321,6 +338,14 @@ 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->list.next = &cpu_buffer->tail_page->list; cpu_buffer->tail_page->list.prev = &bpage->list; @@ -328,19 +353,46 @@ 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_link_flag(bpage, SIMPLE_RB_LINK_HEAD); + 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 = 0; } +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)) -- 2.49.0.967.g6a0df3ecc3-goog