From nobody Sat Nov 30 10:33:29 2024 Received: from mail-pj1-f66.google.com (mail-pj1-f66.google.com [209.85.216.66]) (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 6EB9B194151; Tue, 10 Sep 2024 12:51:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.66 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725972692; cv=none; b=MYARW+/arwob3tDmVsXOkOv0DGubblnW8iwerix+8YRRggHPb46I4n5Abj2ipLENChHAYdv7nMMdyMNDbi8/oO2jy2VmDxK12deJPNN4Bc4ItCCX8/NTmGNj+hi+nqV588mh7l1T3XJpMXXynYb+ZcZN7VPhGKoh+KPxrEL4F80= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725972692; c=relaxed/simple; bh=KOEEs/y0FGCkb+klP+KV9yU4iwr2GAi37Ho3J9O83lo=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Wayw5PzdHqZfbiGA/ogIg/jJInyiOftsA4QJ63mqcoSdYzDokySg1LYpZZaVqq9L6xMXrHrEf8E2SVp/s1HNIrpAtpx+YaWHdjnSeAQ7aEc0kbHLDNEktyg3MhOM1cl5WPMVlIM5xGgNAvaxozUiBjU7hEZyBygnxVD2DG5+mLI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=igdDk91h; arc=none smtp.client-ip=209.85.216.66 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="igdDk91h" Received: by mail-pj1-f66.google.com with SMTP id 98e67ed59e1d1-2d87f34a650so3775966a91.1; Tue, 10 Sep 2024 05:51:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1725972691; x=1726577491; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=UwvRv3wJIDozdKt4626HoR6j934EORaOhOiizGhVlEQ=; b=igdDk91hty9Ab+0Xo8EvOIEHwZehcXBVPNeneiXAt2uEe1dkJN8XjXfwrM5p7udGCk vlQ3dY1wKpD+PYrioHMgQC3d3uU2ajwj2V7xloDsW28iJAduBA+z2IRNVPQN17VMkKUg nevaGYVMlZzxn32EQD8/gSlMfEoAjCPEoaQsMofnz+aXrrPDyXiCc/F0WnS9Zj7WZULt 8iwDRAm3WbYYZubRA/RRbGVAyfIV0ST3kvCWzHfQbsOZ7Z6RI0LSIheNA5eJdgUZ+IL6 ssqBpV52qRxbnVMf5L/qNXBnyeErokkC/qw36CQiFW+qEhCM+SE6geRaCZ15D/UNYvQS jOcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725972691; x=1726577491; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=UwvRv3wJIDozdKt4626HoR6j934EORaOhOiizGhVlEQ=; b=qmtuX7gIORaz4qMe7idDxwtjst7dXUtY/nQ/nK6f3aOaD+ePzKuclQBNUmj4WiOh+6 6mKEQdsnOwodJlrAPFUeKDg00hmiPxviW8CPH88wxUqOrGiOc8AXgVXHoz6LrD3keSsp ufnJuZgSwhjJpZk68tb+JKZTFdvNKG2nQzQT8bpRAr5YhxCZeni3dWw7Zp+oCUqqYVaJ 1dedChjgdUmSEAiOcsABJBYRrIRM7vA0MjFSp5v3GugD0ZVWQB6Wjyim6DXAUIcHBfVy mFYo1nlyQH4GFqKOQ+tyn4LIgVeDhBy54ilHTwyB38GA7VVbaGf74EG00tF/taNg+o3x iZLQ== X-Forwarded-Encrypted: i=1; AJvYcCVFrhxL5TbxVxtYcda0E9X/kwwOLc7uAyNQQUTMvzJz+JYOw+bB/q6U3c4JqRKm5UsbR4l5GjqjqL0=@vger.kernel.org, AJvYcCVLPOWlmrG7/p/byXZilJm3h+NxdhORLD0Ys06a+lDKlVUbPvqEusXW8P0FxWMZPhHeEMGgCgOOPV+X44g=@vger.kernel.org, AJvYcCX1ZUpPOp81AlO8v8xNrrZwvCy9yaEbPNMf3lZQkAxuP/UPt4BTWXv62N4Fzs1v7oKdyhQzWTg1CxXj5aA=@vger.kernel.org, AJvYcCX83EYqqJmdKNMqBqvnCRSEff9NwOV1GIr0KeZ24u3CsZamqUZRIYymU8W86C1i0g2toQpqv1m9jMH6nQ==@vger.kernel.org X-Gm-Message-State: AOJu0YxsjZ6QlJHbPxC8Kjz/EEYmwbN7p8nkI5wD4mXZCJ0UoiS0gD9P q9cTAlt08eK9inq30IhpBVAmqcnEQR1YuoV9NShSADoKYhY7YQr8 X-Google-Smtp-Source: AGHT+IGroNxXPo2q0iinhOTGCE7e5d5prqrWOJ0qJja22FenNOZ6SsoWGZUouzQvScBqrLr4XaHpcw== X-Received: by 2002:a17:90a:9e4:b0:2c9:7343:71f1 with SMTP id 98e67ed59e1d1-2db671d9d58mr4299989a91.14.1725972690657; Tue, 10 Sep 2024 05:51:30 -0700 (PDT) Received: from localhost ([212.107.28.55]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2db044f37dasm6265325a91.34.2024.09.10.05.51.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Sep 2024 05:51:30 -0700 (PDT) From: Celeste Liu X-Google-Original-From: Celeste Liu Date: Tue, 10 Sep 2024 20:51:10 +0800 Subject: [PATCH v3 4/4] arm: defconfig: drop RT_GROUP_SCHED=y from bcm2835/tegra/omap2plus 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" Content-Transfer-Encoding: quoted-printable Message-Id: <20240910-fix-riscv-rt_group_sched-v3-4-486e75e5ae6d@gmail.com> References: <20240910-fix-riscv-rt_group_sched-v3-0-486e75e5ae6d@gmail.com> In-Reply-To: <20240910-fix-riscv-rt_group_sched-v3-0-486e75e5ae6d@gmail.com> To: Paul Walmsley , Palmer Dabbelt , Albert Ou , Guo Ren , Anup Patel , Heinrich Schuchardt , Huacai Chen , WANG Xuerui , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , Russell King , Florian Fainelli , Broadcom internal kernel review list , Ray Jui , Scott Branden , Tony Lindgren , Thierry Reding , Jonathan Hunter Cc: Palmer Dabbelt , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linux-sh@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rpi-kernel@lists.infradead.org, linux-omap@vger.kernel.org, linux-tegra@vger.kernel.org, Stefan Wahren , Kevin Hilman , Celeste Liu X-Mailer: b4 0.15-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=2991; i=CoelacanthusHex@gmail.com; h=from:subject:message-id; bh=KOEEs/y0FGCkb+klP+KV9yU4iwr2GAi37Ho3J9O83lo=; b=owJ4nJvAy8zAJfY4pvNJRPo6U8bTakkMaQ8cjir6+kzR+lXemlktLKMwjd0/+nsN053LZ/95b tR0LFP2z+0oZWEQ42KQFVNkEdv59PWy0kcflvGazICZw8oEMoSBi1MAJrKZg5HhTsqW+5GH5+f+ PfjZ/6VgcMRh1595TKq7D4cys8gH9mkpMTKsn7GpjoXF8dtcKaszT4L+POBuC/yTIPtRKmja47U cUz7zAQA0aEnq X-Developer-Key: i=CoelacanthusHex@gmail.com; a=openpgp; fpr=892EBC7DC392DFF9C9C03F1D15F4180E73787863 Commit 673ce00c5d6c ("ARM: omap2plus_defconfig: Add support for distros with systemd") said it's because of recommendation from systemd. But systemd changed their recommendation later.[1] For cgroup v1, if turned on, and there's any cgroup in the "cpu" hierarchy = it needs an RT budget assigned, otherwise the processes in it will not be able= to get RT at all. The problem with RT group scheduling is that it requires the budget assigned but there's no way we could assign a default budget, since = the values to assign are both upper and lower time limits, are absolute, and ne= ed to be sum up to < 1 for each individal cgroup. That means we cannot really com= e up with values that would work by default in the general case.[2] For cgroup v2, it's almost unusable as well. If it turned on, the cpu contr= oller can only be enabled when all RT processes are in the root cgroup. But it wi= ll lose the benefits of cgroup v2 if all RT process were placed in the same cg= roup. Red Hat, Gentoo, Arch Linux and Debian all disable it. systemd also doesn't support it. [1]: https://github.com/systemd/systemd/commit/f4e74be1856b3ac058acbf1be321= c31d5299f69f [2]: https://bugzilla.redhat.com/show_bug.cgi?id=3D1229700 Tested-by: Stefan Wahren Acked-by: Kevin Hilman Signed-off-by: Celeste Liu --- arch/arm/configs/bcm2835_defconfig | 1 - arch/arm/configs/omap2plus_defconfig | 1 - arch/arm/configs/tegra_defconfig | 1 - 3 files changed, 3 deletions(-) diff --git a/arch/arm/configs/bcm2835_defconfig b/arch/arm/configs/bcm2835_= defconfig index b5f0bd8dd536990a0726e73a6855d25c1286a768..27dc3bf6b124c2012b7a1a768f2= f900f49903cd1 100644 --- a/arch/arm/configs/bcm2835_defconfig +++ b/arch/arm/configs/bcm2835_defconfig @@ -7,7 +7,6 @@ CONFIG_BSD_PROCESS_ACCT=3Dy CONFIG_BSD_PROCESS_ACCT_V3=3Dy CONFIG_LOG_BUF_SHIFT=3D18 CONFIG_CFS_BANDWIDTH=3Dy -CONFIG_RT_GROUP_SCHED=3Dy CONFIG_CGROUP_FREEZER=3Dy CONFIG_CPUSETS=3Dy CONFIG_CGROUP_DEVICE=3Dy diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2p= lus_defconfig index 3a166c2f02bd80634fee3bd8c4579fdbad84ccfa..9cb265c8d4144ea9a41f02640db= c8a06b710323b 100644 --- a/arch/arm/configs/omap2plus_defconfig +++ b/arch/arm/configs/omap2plus_defconfig @@ -13,7 +13,6 @@ CONFIG_MEMCG=3Dy CONFIG_BLK_CGROUP=3Dy CONFIG_CGROUP_SCHED=3Dy CONFIG_CFS_BANDWIDTH=3Dy -CONFIG_RT_GROUP_SCHED=3Dy CONFIG_CGROUP_FREEZER=3Dy CONFIG_CPUSETS=3Dy CONFIG_CGROUP_DEVICE=3Dy diff --git a/arch/arm/configs/tegra_defconfig b/arch/arm/configs/tegra_defc= onfig index d2a094ad360cefefbc3bd35226c5d23eadce42c1..3a9bda2bf422b14085c60b39a2c= 3df86fe0994bb 100644 --- a/arch/arm/configs/tegra_defconfig +++ b/arch/arm/configs/tegra_defconfig @@ -6,7 +6,6 @@ CONFIG_IKCONFIG=3Dy CONFIG_IKCONFIG_PROC=3Dy CONFIG_CGROUPS=3Dy CONFIG_CGROUP_SCHED=3Dy -CONFIG_RT_GROUP_SCHED=3Dy CONFIG_CGROUP_FREEZER=3Dy CONFIG_CGROUP_CPUACCT=3Dy CONFIG_CGROUP_DEBUG=3Dy --=20 2.46.0