From patchwork Tue Sep 10 12:51:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Celeste Liu X-Patchwork-Id: 13798500 Received: from mail-pg1-f195.google.com (mail-pg1-f195.google.com [209.85.215.195]) (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 81956192D97; Tue, 10 Sep 2024 12:51:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725972689; cv=none; b=Yn39ESnohWqRWnhzE0UUprewm5vHXXcFt/fKn2t+boaBg2e9SFf/LwnnikKgzqTC/Uj4MH//O7rr7NF1sTVrSnNuP/NLhyFBhzeMQk9UVMk4ZGFP1P4S5hYkRAbYvkWqVj4nA1mMsRT5Bc3b0XoB+n99QsnNNER0wUuOSIi2c8E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725972689; c=relaxed/simple; bh=i4dMYbikEhftIrSd1gq7tvjKJfStRheJwUa1Cpif+Lw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ASLlpmXTzyzu+ltegqgAMZ7o4yiVQVGvCz2QXnrc0HZZLUycV5ofoUlOPXaSiiZHLPUuA5w/U8R8c3k8U1No3sSjxIyjCrwKwkC1sbeQgyanGcjTtjYYDkp9rRRhjsKJE8EojaFYzCLgCoxOz/94fIgNdk7aisHoi0PhWb9+ulQ= 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=T+qyQnOL; arc=none smtp.client-ip=209.85.215.195 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="T+qyQnOL" Received: by mail-pg1-f195.google.com with SMTP id 41be03b00d2f7-7dafd9df795so605647a12.1; Tue, 10 Sep 2024 05:51:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1725972688; x=1726577488; 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=2bAopf7ujBU/05x/Zo+oSjXvUJSVgeIkGsnSfUiFe/M=; b=T+qyQnOL8P/fLsuTI27tyrOjnlhWpH3xK3M27axLvVcNkIt81qi+MSVxOP8x9Limz+ BoFjBZadxfPZosv9aXQ9OPR6e85gmpMox58X3Qe7xHWhPWMkU6X9jMOuCXYf3A+Bts87 HQHgPJifRSv3DMe8qzg+ukLqsy7Q8atFX6wJaEK6CIGCZmq4+pw4mTxxEmn/4BL3VuRr 1FcWPcimgnszj2szLC/jc0348wRaBd7ssZkOSTqojsX29eJdpKAvfTx6g1PCJA2TEQoV voU0qzhaCQtaQWxI1sOlVvUa4u0UjAmD2pmktuf+ioNBdyQBSbFQy4QDLuhERpT4s2lC siDA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725972688; x=1726577488; 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=2bAopf7ujBU/05x/Zo+oSjXvUJSVgeIkGsnSfUiFe/M=; b=wyKJkXz1MBY3IjjfyNFc4QRFaPGXDuXhiDtfe0qEDNniyPFl+W+9g2gVrvdTgNfOE6 ldIqXuyacfgVSb+7s82gFKS8x6oe9vSPcrM/POHHnZkk9i/BpbfQ07AqBKtBKIwyR/Rq 2RGLlQZT/70Rtca6MXX/8qXyiX4I2gLaeNOtZgZPdttgfrnKmZnhlzMDLFQbKZwTSuP8 sHkWWB1v7XPEwvVp+N/G2Mtga0GtNmIQbT+F293CCc6cna3+73r2ZlUlv1dmup1M2Gvf adBunv6LsbrhiJzfSgyYNhUtMcMtIMAoJkRuDbVar/wZbUsg+q39RUNrQ/CXGezhBJOr Nyew== X-Forwarded-Encrypted: i=1; AJvYcCU0u87t6rvNsZNA8LQDDHnrBcm/HtfWMx8KEj7z6wlsnKmPGNyLnzLGm5k0fjKIDLiP8SHSKxBHY10=@vger.kernel.org, AJvYcCUVuk3qMCbr479DhccvO5uDeysf70od57V/52QfY8N0TLWDiaR/4tgBOFcRZFCucMarHVNb3hkreZT9Cek=@vger.kernel.org, AJvYcCUfnfeDedVyxPFLZEKHJdcLChCiUG9nn5zvSUWuTZxAhOddrgf1fhxLYxTo8j1Ee+Mvn4HAXe6wOdWgPg==@vger.kernel.org, AJvYcCW43CJP5dFthGHRsNY4VcqP70r7aJTLtBsf2yH/OBTvwKw5c58i7wjgV1C/cKx+e2zL8ne+90YlfhF3cxc=@vger.kernel.org X-Gm-Message-State: AOJu0YzhlwA4jMY3EkI4MhAy1UoBuuh47KDQLircSkR3j2thY2JCWosO 3LpffnS2nImx1A5m1N+v+qYOkN4+gC+h9xhZVW/IoGxU47yRRbdq X-Google-Smtp-Source: AGHT+IHgHbCzgcyX/yq2/aN5BrFUKFDAFGLiltGw+vmIZ7aKbx1Z6fmvlBgd0wE3EiRb5/sbMP7HqA== X-Received: by 2002:a05:6a21:150c:b0:1ca:981:8e4e with SMTP id adf61e73a8af0-1cf5e096a13mr901315637.3.1725972687795; Tue, 10 Sep 2024 05:51:27 -0700 (PDT) Received: from localhost ([212.107.28.55]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2db04966b75sm6317071a91.36.2024.09.10.05.51.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Sep 2024 05:51:27 -0700 (PDT) From: Celeste Liu X-Google-Original-From: Celeste Liu Date: Tue, 10 Sep 2024 20:51:09 +0800 Subject: [PATCH v3 3/4] sh: defconfig: drop RT_GROUP_SCHED=y from sdk7786/urquell Precedence: bulk X-Mailing-List: linux-sh@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240910-fix-riscv-rt_group_sched-v3-3-486e75e5ae6d@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, Celeste Liu X-Mailer: b4 0.15-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=2143; i=CoelacanthusHex@gmail.com; h=from:subject:message-id; bh=i4dMYbikEhftIrSd1gq7tvjKJfStRheJwUa1Cpif+Lw=; b=owJ4nJvAy8zAJfY4pvNJRPo6U8bTakkMaQ8cjhgVSl/QKw754HE9X+Szg08Pp2726RsspZo1s cuehoW11HeUsjCIcTHIiimyiO18+npZ6aMPy3hNZsDMYWUCGcLAxSkAE5EsZGSYdUDWq+zSzrNb uf2nMx3iy3m2PDCA48XSy62/naf1Wu9cwvBXwMtR5NxLTpaWCzuFXEqvq6VyxJlzXj0uYqrOt+/ TP1EOAFFySKE= X-Developer-Key: i=CoelacanthusHex@gmail.com; a=openpgp; fpr=892EBC7DC392DFF9C9C03F1D15F4180E73787863 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 need to be sum up to < 1 for each individal cgroup. That means we cannot really come up with values that would work by default in the general case.[1] For cgroup v2, it's almost unusable as well. If it turned on, the cpu controller can only be enabled when all RT processes are in the root cgroup. But it will lose the benefits of cgroup v2 if all RT process were placed in the same cgroup. Red Hat, Gentoo, Arch Linux and Debian all disable it. systemd also doesn't support it.[2] [1]: https://bugzilla.redhat.com/show_bug.cgi?id=1229700 [2]: https://github.com/systemd/systemd/issues/13781#issuecomment-549164383 Signed-off-by: Celeste Liu --- arch/sh/configs/sdk7786_defconfig | 1 - arch/sh/configs/urquell_defconfig | 1 - 2 files changed, 2 deletions(-) diff --git a/arch/sh/configs/sdk7786_defconfig b/arch/sh/configs/sdk7786_defconfig index 7b427c17fbfecb24d63e717023aad19ce1c953e8..3599b1683593b865d863800eb84b3f8f89d3d57e 100644 --- a/arch/sh/configs/sdk7786_defconfig +++ b/arch/sh/configs/sdk7786_defconfig @@ -17,7 +17,6 @@ CONFIG_CPUSETS=y CONFIG_CGROUP_CPUACCT=y CONFIG_CGROUP_MEMCG=y CONFIG_CGROUP_SCHED=y -CONFIG_RT_GROUP_SCHED=y CONFIG_BLK_CGROUP=y CONFIG_RELAY=y CONFIG_NAMESPACES=y diff --git a/arch/sh/configs/urquell_defconfig b/arch/sh/configs/urquell_defconfig index 00ef62133b04ded8d0b4221f11e0adafde99d386..9cf4a719001ea5ef4b031c1bbbf8098e8af5a2b2 100644 --- a/arch/sh/configs/urquell_defconfig +++ b/arch/sh/configs/urquell_defconfig @@ -15,7 +15,6 @@ CONFIG_CPUSETS=y CONFIG_CGROUP_CPUACCT=y CONFIG_CGROUP_MEMCG=y CONFIG_CGROUP_SCHED=y -CONFIG_RT_GROUP_SCHED=y CONFIG_BLK_DEV_INITRD=y CONFIG_PROFILING=y CONFIG_MODULES=y