From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E5B493E5A2F for ; Fri, 16 Oct 2026 14:31:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792161098; cv=none; b=qP1E4kFeJL89xYIgu3ivd4rNDPJvdkh2ZblmwZNAXeIE5mgKs6P2Sc4qCvlHN7xPXMQHA9qP+/2g4gvFFk3sa+RxWpWiefBVnc80cJUnqEgQz/D3jc6JtdFNiqk5MSn9jsllxGBS/hxeC7b9MkvCgpTbC0O+bWaZ0CGKAITgrQw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792161098; c=relaxed/simple; bh=vRqyePzXSGR4tKuoIKteIcUpYt8Nyg299P4AcbgNSlc=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=O6rKUXjoF3ldWv9N/sdW0k359oLiXhRwMqBnHh3s7iVklIJcn/+c6WLFl6EjHJohdcEGemMGwcPWs2Ib87dx3yDbXG7xzNP3D88HE/H3+qXFTSzZbyJsy1k9WmAZwOrQENx9B0XXghZzIIymlutNDZe6aW1Qv4Uv3o7w6+Slerg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Z0AG5EbY; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Z0AG5EbY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C618D1F000C5; Fri, 16 Oct 2026 14:31:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792161096; bh=d3RmsGujCQW2wwVTfLTMDo7/s0dpsegfHFrwZ9Dww4U=; h=Date:From:To:Cc:Subject:References; b=Z0AG5EbY7StbvQMOddR4pzjPyEKGbMV2Qo//Y+z+voD+tNXpYqK00JmmrpFt7Wd5Y 3XsVuBObvIxC4R7JEqKf9W8jdZ3IECmcgRAo1Z1rLacRW0e5cgLYFKHKtz8l5irdmM A+ruFCIjrFIv8dl0MGcdB23gcivzb8VWXwCVbr/bbJxmdNzH2GgoQ/WadsC/+98Ha6 MgoZZjTPjoBHPSTBmgrOgsHMhvCIXQu7iMCDvo9iMUAOM1Ro3LGbhsLJqI7/+7QKlR T8btGm6GeYotdotGbqzuHz1BlZsxlv9SyKfMudftgvDQJtaV1RvraTWBUVNmyCirQq DMVr62V+8vctQ== Received: from rostedt by gandalf with local (Exim 4.100.1) (envelope-from ) id 1xHiy8-00000000XlP-0YKn; Fri, 16 Oct 2026 10:31:36 -0400 Message-ID: <20261016143135.930816404@kernel.org> User-Agent: quilt/0.69 Date: Fri, 16 Oct 2026 10:31:24 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Vincent Donnefort Subject: [for-next][PATCH 09/18] ring-buffer: Rename ring_buffer_size() to ring_buffer_capacity() References: <20261016143115.392980228@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: Vincent Donnefort Since commit 8a5f63637890 ("ring-buffer: Fix subbuf resize race with ring buffer readers"), "capacity" refers to the memory available for events (excluding subbuffer headers) while "size" refers to the raw allocation. ring_buffer_size() actually calculates this event capacity. Rename it to ring_buffer_capacity() to align with this convention. Link: https://patch.msgid.link/20260908090937.838544-2-vdonnefort@google.com Signed-off-by: Vincent Donnefort Signed-off-by: Steven Rostedt --- include/linux/ring_buffer.h | 2 +- kernel/trace/ring_buffer.c | 13 +++++++++---- kernel/trace/trace.c | 6 +++--- 3 files changed, 13 insertions(+), 8 deletions(-) diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h index eac3e9080c3c..9855c7365f67 100644 --- a/include/linux/ring_buffer.h +++ b/include/linux/ring_buffer.h @@ -166,7 +166,7 @@ void ring_buffer_iter_reset(struct ring_buffer_iter *iter); int ring_buffer_iter_empty(struct ring_buffer_iter *iter); bool ring_buffer_iter_dropped(struct ring_buffer_iter *iter); -unsigned long ring_buffer_size(struct trace_buffer *buffer, int cpu); +unsigned long ring_buffer_capacity(struct trace_buffer *buffer, int cpu); unsigned long ring_buffer_max_event_size(struct trace_buffer *buffer); void ring_buffer_reset_cpu(struct trace_buffer *buffer, int cpu); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 04bb94c29f58..289bae003d7f 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -6546,18 +6546,23 @@ void ring_buffer_iter_advance(struct ring_buffer_iter *iter) EXPORT_SYMBOL_GPL(ring_buffer_iter_advance); /** - * ring_buffer_size - return the size of the ring buffer (in bytes) + * ring_buffer_capacity - return the capacity of the ring buffer (in bytes) * @buffer: The ring buffer. - * @cpu: The CPU to get ring buffer size from. + * @cpu: The CPU to get ring buffer capacity from. + * + * Capacity is the total memory available for recording event data in the + * ring buffer. It excludes subbuffer headers. + * + * Returns the capacity in bytes, or 0 if the CPU is not set in the buffer mask. */ -unsigned long ring_buffer_size(struct trace_buffer *buffer, int cpu) +unsigned long ring_buffer_capacity(struct trace_buffer *buffer, int cpu) { if (!cpumask_test_cpu(cpu, buffer->cpumask)) return 0; return rb_subbuf_capacity(buffer) * buffer->buffers[cpu]->nr_pages; } -EXPORT_SYMBOL_GPL(ring_buffer_size); +EXPORT_SYMBOL_GPL(ring_buffer_capacity); /** * ring_buffer_max_event_size - return the max data size of an event diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index e4a490d3d08c..1054c9b29aed 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4712,9 +4712,9 @@ void trace_set_buffer_entries(struct array_buffer *buf, unsigned long val) static void update_buffer_entries(struct array_buffer *buf, int cpu) { if (cpu == RING_BUFFER_ALL_CPUS) { - trace_set_buffer_entries(buf, ring_buffer_size(buf->buffer, 0)); + trace_set_buffer_entries(buf, ring_buffer_capacity(buf->buffer, 0)); } else { - per_cpu_ptr(buf->data, cpu)->entries = ring_buffer_size(buf->buffer, cpu); + per_cpu_ptr(buf->data, cpu)->entries = ring_buffer_capacity(buf->buffer, cpu); } } @@ -8520,7 +8520,7 @@ int allocate_trace_buffer(struct trace_array *tr, struct array_buffer *buf, int /* Allocate the first page for all buffers */ trace_set_buffer_entries(&tr->array_buffer, - ring_buffer_size(tr->array_buffer.buffer, 0)); + ring_buffer_capacity(tr->array_buffer.buffer, 0)); return 0; } -- 2.53.0