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 ACD7B337BA4 for ; Sun, 6 Sep 2026 01:44:13 +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=1788659054; cv=none; b=fXGWpIvLKbA6hEXTFlhH2WUxYp3cr4NoOyajg2UNt9Z2RfuylUrpq3C2TW2721cWaWmPvf627STrZ6fvPakwsP9vVCAKUPD5KM4t6L+TCTvqHzi4+fXFxMe3Yg/26/Xb7d4f+XB3+qUqcC2DuIDpK5GOvJQQaHvwKmCj8eadtb0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788659054; c=relaxed/simple; bh=seoBvo7fTTRH4weJ9hmbvv6nuBcjndCagbe16XTPuhw=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=CToplHlCUIps3n0IMcbVjjw+XRbObiyKCYgG43QG7VscVOw5vzzr54Q3ih1y8zJ21jC+YEWqzqXlEHLbfsBIQ7aoKmREPvcxxMDgOFSD3+oY4P7vZAZdU/VY2j2i5JRiblhV8OWjzDY/InzIfX3kdR1bEWRLxmUlPjGWCVUmgoY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dHctnYk2; 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="dHctnYk2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 665761F00A3D; Sun, 6 Sep 2026 01:44:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788659053; bh=1XbNGsPvuLsPJbCOotGpbVqbsKtkw9+ECgLpRwY2MC8=; h=Date:From:To:Cc:Subject:References; b=dHctnYk2CtyZluxbjHOro6TgftNg4OzmCSO+xra7KSW/4COSngeTjN5gHx1dzy/jm Qjm5I5zLT21FiYpJ53v0pfrtDgz2imLWPEDFwxyTgB1RqcmQYejepqAZx4Z8eSUwoJ Rr0JGcWJgVubxy/oFFe3EtYifgKL6Y1Nor1niPOUTEOUbJB9k2nfv5IEr3JxvtA68m 8DbKANWxTImW6kALeN6QJQEKW0FiP36Z54kC1L9Bs5m8dnBGbS2NpAjUb7q8wWasjC if04Sk8AJiBzuRnjV+GaBB88sjkL4WAr+XM5J1otkX41qOmyu7ibRUyBtnzgmBCm7m Yoym+hVzJ4wRw== Received: from rostedt by gandalf with local (Exim 4.99.4) (envelope-from ) id 1x2whQ-00000006JEB-3CJi; Sat, 05 Sep 2026 16:09:16 -0400 Message-ID: <20260905200916.632947591@kernel.org> User-Agent: quilt/0.69 Date: Sat, 05 Sep 2026 16:08:39 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Vincent Donnefort Subject: [for-linus][PATCH 12/12] ring-buffer: Use a macro for static buffer bits References: <20260905200827.773347757@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: Steven Rostedt Instead of hard coding 30 for the number of bits used for the static buffer ids in two places, create a macro. This way if it changes in the future, it will change in all the locations that use it. Link: https://patch.msgid.link/20260904151641.17eae0aa@gandalf.local.home Signed-off-by: Steven Rostedt --- kernel/trace/ring_buffer.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 220b8405adfc..b88c75b52e8f 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -335,6 +335,9 @@ static __always_inline unsigned int rb_read_page_capacity(struct buffer_data_rea return (PAGE_SIZE << rpage->order) - BUF_PAGE_HDR_SIZE; } +/* The number of bits for static buffer ids */ +#define RB_STATIC_BITS 30 + /* * Note, the buffer_page list must be first. The buffer pages * are allocated in cache lines, which means that each buffer @@ -350,7 +353,7 @@ struct buffer_page { local_t entries; /* entries on this page */ unsigned long real_end; /* real end of data */ unsigned order; /* order of the page */ - u32 id:30; /* ID for external mapping */ + u32 id:RB_STATIC_BITS; /* ID for external mapping */ u32 range:1; /* Mapped via a range */ struct buffer_data_page *page; /* Actual data page */ }; @@ -663,7 +666,7 @@ static unsigned long rb_static_max_pages(void) * Static ring buffers are using bpage::id and must account for the * reader page. */ - return (1UL << 30) - 1; + return (1UL << RB_STATIC_BITS) - 1; } struct ring_buffer_iter { -- 2.53.0