From nobody Fri Dec 19 22:06:06 2025 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (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 A68C61B0F1E for ; Fri, 16 May 2025 13:40:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747402861; cv=none; b=nco1jA2joKbOjKWosJUzE+xkfOkRawwSdMSvozk2fwEBJpBA844pcxkrrjbQnrHJWxbm6LP4RwpQSbiJh9qu+2V5rnH/JUOwrEpUJq4mazRUuP4hI3VcjzRBlfLvgu9jIOPSYvwev2ILYsWGpw7bpmgBjiIOA0lycovQMf3ClxA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747402861; c=relaxed/simple; bh=VXhc6kuUvVh88rMf6Dfs48+dusU9+NFd7/XvHXsuLFc=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=NMCEuPHG62Q1Vm5mUBAMXuj/ER8kir+NtK0+8TRGM12ZwdHpVHGH6RbIzpcv0YQUviUXnU0sEv7Oltiln22DTFTukibmNpaccqzz8w1gac2cElTXpRHa1AwqcKYhu3dLHx93hxgbcNPohxkDOH2+MU2eedRbXiAGDEmS1xMJC7c= 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=1BfpOvZd; arc=none smtp.client-ip=209.85.128.73 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="1BfpOvZd" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-43cfda30a3cso11917475e9.3 for ; Fri, 16 May 2025 06:40:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1747402858; x=1748007658; 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=pqHHSd/acUgt02haNYwh+lCiOm/YA61Dyq06MdhKSUs=; b=1BfpOvZdLuI6GJiB7nv+T/qb30panCCN3EvudmB3GUml0E1xFn08GivdoUqXhuq0qq OvLhFPqOHMTNuSpVjQnbfHy9TAuLXVIZDhO+L1wwiT12JNzRPb2IIztLD9CHAK9caJI+ Z8xM5NicVeDmB0FjcYAAwWABq0qg8Q5Y8fYCwaBdlb31o0sycgfgjsFv9Q/2aSPRsLHj ydUjeje5hy1TSO9vkWeYCSHryHuf2C6BahfJTbrDeTyphEKInSwA/4am0Pd/zyVAQ2o9 Mv9CqaUbiqbfq5NArDnDkHEbwf5jeVlI7lHaAHLJDU3WlysbS2i48KvqFOcHUPR4Thy5 pe8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1747402858; x=1748007658; 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=pqHHSd/acUgt02haNYwh+lCiOm/YA61Dyq06MdhKSUs=; b=mtedx3xIQr/SSzCiXVWqoFc9B+Wtg6WOmK3NL/gfRRt8O2ehrhljym1NIUQ2OHFKy0 XdLD7ySxWA8worXwkqusSsaW3bB06PgQy0wsodr5QTPa+zxfnNMDvQ12wFF6Gw3nUnFL wrqWsT3/pdKpS3K2zA9mfcm2eSuNa+qyMKgvb8p2EaKs6Nv3nQN6dxK32E+msMTc6RQo GZ742V5XniqX8pJXA+XBdWGq0UNx7I2KB9q7C8GIcENRq36YVAxiDhTm+pJaeHhzy33o VQBOjotSHAHsnrmHVqwKAczNwpLHZCKNq2V3xdOsOsvSy9TlL8K3imjUr0dPfl0hZ2PN eXOA== X-Forwarded-Encrypted: i=1; AJvYcCU7HeYzQf+pn3fPD5bBwig2yZe7kuRX0VB1/bWtsOx3qFuFtSvvfeRIb2sZ536+0yaeAp4FLD/EpnFFTH4=@vger.kernel.org X-Gm-Message-State: AOJu0YxDaf4AtVky41i3YlgbuksHww/hLIezLlikYw7wB5HzxTfp7Zhg NltqxpT8nbviB4/sNkSKf3rR3LObR456OBsxbGpHwR+lYvkVDMspu1Zqpvd62B4ldMe9rLFXnGl C0G3PZq53TGlg3nMGkGVvhw== X-Google-Smtp-Source: AGHT+IERHQk7zgcioL7fmaIDqK4DV/c0A3+lhvu9kgl4ryWQaxYhNaW0ruiCml2zAVK/r7QIv2zASe+SXD169wcB X-Received: from wmrn6.prod.google.com ([2002:a05:600c:5006:b0:441:bc26:4d3f]) (user=vdonnefort job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:548e:b0:442:dc6f:7a21 with SMTP id 5b1f17b1804b1-442fefd5f18mr31225325e9.3.1747402858314; Fri, 16 May 2025 06:40:58 -0700 (PDT) Date: Fri, 16 May 2025 14:40:19 +0100 In-Reply-To: <20250516134031.661124-1-vdonnefort@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250516134031.661124-1-vdonnefort@google.com> X-Mailer: git-send-email 2.49.0.1101.gccaa498523-goog Message-ID: <20250516134031.661124-14-vdonnefort@google.com> Subject: [PATCH v5 13/25] 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-Transfer-Encoding: quoted-printable 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 d6761dc2f404..e74707f10b93 100644 --- a/include/linux/simple_ring_buffer.h +++ b/include/linux/simple_ring_buffer.h @@ -47,4 +47,12 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu *cp= u_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_buff= er); 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_b= uffer.c index 3efdb895d77a..56b4701979ba 100644 --- a/kernel/trace/simple_ring_buffer.c +++ b/kernel/trace/simple_ring_buffer.c @@ -64,7 +64,7 @@ static void simple_bpage_reset(struct simple_buffer_page = *bpage) local_set(&bpage->page->commit, 0); } =20 -static void simple_bpage_init(struct simple_buffer_page *bpage, unsigned l= ong page) +static void simple_bpage_init(struct simple_buffer_page *bpage, void *page) { INIT_LIST_HEAD(&bpage->list); bpage->page =3D (struct buffer_data_page *)page; @@ -290,10 +290,15 @@ int simple_ring_buffer_reset(struct simple_rb_per_cpu= *cpu_buffer) return 0; } =20 -int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct s= imple_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 =3D bpages; + int ret =3D 0; + void *page; int i; =20 /* At least 1 reader page and one head */ @@ -302,15 +307,22 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu = *cpu_buffer, struct simple_ =20 memset(cpu_buffer, 0, sizeof(*cpu_buffer)); =20 - cpu_buffer->bpages =3D bpages; + cpu_buffer->meta =3D load_page(desc->meta_va); + if (!cpu_buffer->meta) + return -EINVAL; =20 - cpu_buffer->meta =3D (void *)desc->meta_va; memset(cpu_buffer->meta, 0, sizeof(*cpu_buffer->meta)); cpu_buffer->meta->meta_page_size =3D PAGE_SIZE; cpu_buffer->meta->nr_subbufs =3D cpu_buffer->nr_pages; =20 /* The reader page is not part of the ring initially */ - simple_bpage_init(bpage, desc->page_va[0]); + page =3D load_page(desc->page_va[0]); + if (!page) { + unload_page(cpu_buffer->meta); + return -EINVAL; + } + + simple_bpage_init(bpage, page); bpage->id =3D 0; =20 cpu_buffer->nr_pages =3D 1; @@ -320,7 +332,13 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu *= cpu_buffer, struct simple_ cpu_buffer->head_page =3D bpage + 1; =20 for (i =3D 1; i < desc->nr_page_va; i++) { - simple_bpage_init(++bpage, desc->page_va[i]); + page =3D load_page(desc->page_va[i]); + if (!page) { + ret =3D -EINVAL; + break; + } + + simple_bpage_init(++bpage, page); =20 bpage->list.next =3D &(bpage + 1)->list; bpage->list.prev =3D &(bpage - 1)->list; @@ -329,6 +347,14 @@ int simple_ring_buffer_init(struct simple_rb_per_cpu *= cpu_buffer, struct simple_ cpu_buffer->nr_pages =3D i + 1; } =20 + if (ret) { + for (i--; i >=3D 0; i--) + unload_page((void *)desc->page_va[i]); + unload_page(cpu_buffer->meta); + + return ret; + } + /* Close the ring */ bpage->list.next =3D &cpu_buffer->tail_page->list; cpu_buffer->tail_page->list.prev =3D &bpage->list; @@ -336,19 +362,46 @@ 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); =20 + cpu_buffer->bpages =3D bpages; + return 0; } =20 -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 s= imple_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; =20 simple_rb_enable_tracing(cpu_buffer, false); =20 + unload_page(cpu_buffer->meta); + for (p =3D 0; p < cpu_buffer->nr_pages; p++) + unload_page(cpu_buffer->bpages[p].page); + cpu_buffer->bpages =3D 0; } =20 +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)) --=20 2.49.0.1101.gccaa498523-goog