From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f170.google.com (mail-pl1-f170.google.com [209.85.214.170]) (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 0BF931C1AB7 for ; Thu, 12 Sep 2024 20:58:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726174691; cv=none; b=IHdWDzOnSMMBDufHvJfpiuzg+i+MYFq3gjrHW+xoTZKTeoSRqJXfg6FS8JmVZLx/g4qZX5QyatcPYvRLBgPK7Rs57Z1esccAaaWTZFDic/CmedfNTueaH23vtkkP2HtOgx4Qb6vDCpjYgaAc1ABoha/e4SvNT+QLeBh+gUZzoNs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726174691; c=relaxed/simple; bh=MYDZvrqlWEpmfJ0PC8MrAJxxkqkqQuxjGFHhVbXAtYE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uOneFg+9HGKcFBuvBH32meYVHFcdahUQXRTNlGMr4ozdNYAyHwIM2RGjZv4vlyJrcIq8sYv0r9Ec7yrsFuyWtcZBIXy0fDRovaTFNZuQhRQy0WPtxa1OMQu0sV1/Y8XniArcnpAx9l6RSYY+ErSL/0MKfHgcyBRPT7HFBbsIsfQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com; spf=pass smtp.mailfrom=rivosinc.com; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b=zMYKHmeH; arc=none smtp.client-ip=209.85.214.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b="zMYKHmeH" Received: by mail-pl1-f170.google.com with SMTP id d9443c01a7336-2068a7c9286so2321625ad.1 for ; Thu, 12 Sep 2024 13:58:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1726174689; x=1726779489; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=awElkTLWK6u37rMcH6vV+9dmrRY/uH5yY9ycJ6GvqvQ=; b=zMYKHmeHeQVgR09jItL/tqN8Iu4Z3xtNVUJI3mfrZ+xz47TgmOXyD7WQL1V+VVGI3b 057mf/boAlQUxGXeRg11VB7fhHybVjqZLyWIvQcSGLVNYAvEv6iVp2R/U2+FSV02jjcd suOfT2n8WEHaIQZ7MAl3Mw314o+l/CEiO4Pp1cMKbQGXY3VLZ/4NDcgIO8whd3++PjfM bYNypxqJ5LyaYGOl2easU6fx3QBQhOBcywyL59Sdf/VWM4nvA43cJPIq7jivxdDaK1Wr 50tRSpf6h/DSxjes6lm4PoYYfAuZHQUzhdoTCApthYu9TE1JgagCpEIBtR2wsA4IRZTO 6LEA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726174689; x=1726779489; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=awElkTLWK6u37rMcH6vV+9dmrRY/uH5yY9ycJ6GvqvQ=; b=bvQJasTLNHqCnTQ+V/Z/z3F367d+W7t45DiCrkegr0cbbMYGfqpagLJNj4DQW8hmMk Emw/Yoheuc5SsDpY8daqd2yrka9Yfc+kdYbohDaj2WVxonL50frErWJXYnM4geha5mLO VftWcPPlmrPhmTzvHEm61pJYIRWeLDWnDbSbHjxOawzYFWG7FfqApC83Ze4ND1m/ET6S hzNMCRH64wLICZm59iBbm2TPlGmQpzDMUFh2Buch4cfKj7O6tATHnMhMnSj4YtHhodvB lMbk63EdOH1Nb0FjdCgJewNNuYpF09nCe3hqis2NteqySgDLCnyJLRxoCSNqAtVMqCny tYFA== X-Forwarded-Encrypted: i=1; AJvYcCVePZwJ1NxKMZ6y0QPe1ZhVKI1sy2hYmp75I8MY57PM1qJrGc3W5idu8RGrvaG+WVdmF2bm9f0GnQ==@vger.kernel.org X-Gm-Message-State: AOJu0YxJ2tAWXtny2Gijm3/v4DA/0Me7rtCsOq/xwYk9JrFSgeNsxI0K +hK/l2VWsOhsOPnACVCeLI89NnuG5ARXgEo1DKONHwLm6SIvykOUQ0idne6gvmM= X-Google-Smtp-Source: AGHT+IFNbFNRlMUVnmzvIAqMYOHLNoYiu39w2cW+++5PhbuKhP72IpMktdJxCrIrvKb5Z0jSCotKrw== X-Received: by 2002:a17:902:f60e:b0:205:809c:d490 with SMTP id d9443c01a7336-20781d61d67mr8439965ad.16.1726174689001; Thu, 12 Sep 2024 13:58:09 -0700 (PDT) Received: from ghost ([50.145.13.30]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2076b0097desm18030445ad.247.2024.09.12.13.58.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Sep 2024 13:58:08 -0700 (PDT) Date: Thu, 12 Sep 2024 13:58:05 -0700 From: Charlie Jenkins To: Celeste Liu Cc: 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 , 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 Subject: Re: [PATCH v3 1/4] riscv: defconfig: drop RT_GROUP_SCHED=y Message-ID: References: <20240910-fix-riscv-rt_group_sched-v3-0-486e75e5ae6d@gmail.com> <20240910-fix-riscv-rt_group_sched-v3-1-486e75e5ae6d@gmail.com> Precedence: bulk X-Mailing-List: linux-sh@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240910-fix-riscv-rt_group_sched-v3-1-486e75e5ae6d@gmail.com> On Tue, Sep 10, 2024 at 08:51:07PM +0800, Celeste Liu wrote: > Commit ba6cfef057e1 ("riscv: enable Docker requirements in defconfig") > introduced it because of Docker, but Docker has removed this requirement > since [1] (2023-04-19). > > 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.[2] > > 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.[3] > > [1]: https://github.com/moby/moby/commit/005150ed69c540fb0b5323e0f2208608c1204536 > [2]: https://bugzilla.redhat.com/show_bug.cgi?id=1229700 > [3]: https://github.com/systemd/systemd/issues/13781#issuecomment-549164383 > > Acked-by: Heinrich Schuchardt > Signed-off-by: Celeste Liu Acked-by: Charlie Jenkins > --- > arch/riscv/configs/defconfig | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig > index 12dc8c73a8acfaa5c8f442968a807de303428d9e..de85c3ab261e6d62b2089a3c89bdc9d1b34fa792 100644 > --- a/arch/riscv/configs/defconfig > +++ b/arch/riscv/configs/defconfig > @@ -9,7 +9,6 @@ CONFIG_CGROUPS=y > CONFIG_MEMCG=y > CONFIG_CGROUP_SCHED=y > CONFIG_CFS_BANDWIDTH=y > -CONFIG_RT_GROUP_SCHED=y > CONFIG_CGROUP_PIDS=y > CONFIG_CGROUP_FREEZER=y > CONFIG_CGROUP_HUGETLB=y > > -- > 2.46.0 > > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv