From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f74.google.com (mail-wr1-f74.google.com [209.85.221.74]) (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 A96E52BEC20 for ; Wed, 11 Feb 2026 15:28:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770823697; cv=none; b=Wg27/rRZaOcFEYtYyjR7qBkFC3hzKSDdgkOSQuPU17eazy1CqE8GSoDHzVFFmFgVUDITXMSr3ZO7se0X6lQ9hrUfaO7o1/mepmJWdRxWUan9Au3l2sx5bJq/y1QM+11W44Ia/WmabAus9qj+A2wEtbEcMtjbxBdQ74BWMa9jPvk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770823697; c=relaxed/simple; bh=aO8W9arBSFeTzB/wHZF3Gt2mXxw0rJsv3DyUpwy8Zvs=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=fD8vEecUkiWlO3EmC2x5OqpxYCVyfyVLV+3mJEko9ZkcxKE74pV8SJl/n+tgpZ3ZlDb5m5rfENjjR6+JQlb8btCANv/yQKdb1jjkcAULlDlbTQS4zDsXqYhn0QLOzxnpV0jFT5R2Hj5UgyNq5TW6ugkoFGCDh9U7ymJ36BD7eX0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=eHus+8Cs; arc=none smtp.client-ip=209.85.221.74 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--aliceryhl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="eHus+8Cs" Received: by mail-wr1-f74.google.com with SMTP id ffacd0b85a97d-4359e322f30so5865286f8f.2 for ; Wed, 11 Feb 2026 07:28:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1770823695; x=1771428495; 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=f7wCBvgeAuRU2AgOY0dYBW2S0n/KzwtQfSNAU31kHXk=; b=eHus+8CsZEw0WuUT4a+AGRiwXsN8LkUsn13qV8r8ZsCN42tQmDd8Bx97/hBPuVf+K8 lo+5E3uGG24KBqCTw+mKMYhPN33kgPmE1wiru/xA2LtDwlUg5AfCQxszSD1HTXsfbEQx KGRh49+LLklWGrevYAA3Ve3CMUDYuk4lyBUXxirHq6oTT49SlTYlbhwEsPSjaxgKdYtx dDLssAeWHZwMRlc+gdUoNiEmDCHkvTwDRIrWrw5Ruio7Cg4YJPhuUVP3+200i5i+5c3A klsQuJmxM88IwG9wyun2KjkTGupq/GxIWQAf5QWnqmgqIrIZudFql2WGek0keuedMo7Q 4Xbw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770823695; x=1771428495; 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=f7wCBvgeAuRU2AgOY0dYBW2S0n/KzwtQfSNAU31kHXk=; b=QR7AREop+K8hoBkxU0EocAJEHmIX0yag36s9FdNMBmYj9HRytnHz7e7mJ66/9HNs+7 FtpoefZXaH16hqVMBbCBVtUWO2U3wMhNwDZDyZDdkG94EQDOqMIIkv1IjsffQKDf1aVs xJnx7vNewVp7Rp6rP6o487G3dq2pNeGG2WdtX+nWapE644LFll+QIIajoBaOSp+l38ox jPQa2xnO5UT4fDq8niRPMPrvfXQ5q86KKCKQA1NwSvhzejLzyAkaXXNfjKgLmeMxzyMr LOqG65dmQccZsvVQanednYMhAeVU9uQWTydopmyquwC8q0nRFCqnqMP7Aq9UhkJgyLUR 8aWw== X-Forwarded-Encrypted: i=1; AJvYcCVttzM0qc5hgOWWmULZn+4KBy27ts2StfDX5jU/wVhEBzYLFI60fwW625XtbqlrY4wQfPkZWA2e6M3ObqY=@vger.kernel.org X-Gm-Message-State: AOJu0Yx9+odhf/cf/d9bgojkq7mtAWS8Yi8LlROwRTdWiJLH2zuQ2rOZ F72KNfFczoSUL0jJoHdUxtbUPpJ/3qYLqlXTdjVuHtH2JQJ5pbRisms8imjipQykhSQpmT2rdFc jzt/fYdRdb+eM3JLU4w== X-Received: from wrbgk4.prod.google.com ([2002:a05:6000:3104:b0:435:c099:c167]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6000:61e:b0:436:3267:3edd with SMTP id ffacd0b85a97d-4377a531914mr9582059f8f.22.1770823695071; Wed, 11 Feb 2026 07:28:15 -0800 (PST) Date: Wed, 11 Feb 2026 15:28:14 +0000 In-Reply-To: <535d0c8637319f14f2d104a928a75ae872be8786.camel@mailbox.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260203081403.68733-2-phasta@kernel.org> <20260203081403.68733-5-phasta@kernel.org> <20260210155750.5cdbe6cc@fedora> <8ea48ce49f2c7b6fd715dd54c24e755e8ac3262c.camel@mailbox.org> <20260211120742.0e9e7122@fedora> <535d0c8637319f14f2d104a928a75ae872be8786.camel@mailbox.org> Message-ID: Subject: Re: [RFC PATCH 3/4] rust/drm: Add DRM Jobqueue From: Alice Ryhl To: phasta@kernel.org Cc: Boris Brezillon , David Airlie , Simona Vetter , Danilo Krummrich , Gary Guo , Benno Lossin , "Christian =?utf-8?B?S8O2bmln?=" , Daniel Almeida , Joel Fernandes , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, rust-for-linux@vger.kernel.org Content-Type: text/plain; charset="utf-8" On Wed, Feb 11, 2026 at 02:53:49PM +0100, Philipp Stanner wrote: > On Wed, 2026-02-11 at 12:52 +0000, Alice Ryhl wrote: > > > > Yes, many people assume "list widely used in kernel" implies "list is a > > good idea". Unfortunately it is not the case. > > > > > > This applies to the red/black tree too, by the way. > > > > > > Can't fully follow, you mean that RB trees are supposedly overused, > > > too? > > > > When I first suggested adding red/black tree abstractions in Rust > > several years ago I was told by Greg that I couldn't do it because the > > red/black tree was deprecated and no new users should be added. > > Do you have a link or sth? I could not easily find it again, sorry. It's been several years now since that discussion. > First time in my life that I hear that RB trees shouldn't be used. If > something is deprecated for good one would hope that's obvious. I'm not sure what the current status is ... it may have been somewhat walked back and is now a "some people do not like rb trees" rather than a deprecation. > What's the justification? Should everyone use the B-Tree? > RB trees are super widely used in CS. The justification is that every time you follow a pointer, it costs a cache miss which is really expensive. Using an xarray or hashtable or vector is much cheaper under most circumstances. RB trees are used widely in CS because they are one of the simplest data structures that provide O(log n) lookup. Such analysis usually does not care about constant factors. Alice