From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (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 D45D943C05C for ; Tue, 28 Apr 2026 13:00:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777381230; cv=none; b=Z0OLW3yEh0rsKdQTycSwTWfd3xi6nIqSOfjgSYWOtfRaBgSOCiTqJF8XIE8T+VJzuOGAzCo0tmkrCfe1zznqHKpzJ7m14hodrR+p9moZpjRMfHx4LdLc2BhCs258W24zb669qWU1ATp1yTtH3oxSlJPhThLAbamLcBt7qmVGzC0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777381230; c=relaxed/simple; bh=pXOTBlzOS4XFAor8wVp44/K+YV3cKSifsR9b0pwKmtQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Aq/SkePXVNDT2mJAtdSGnaRWpuh7qTh11FAC2H0C+ALSIi1MRp3zk0EYhV14qs5DdRuk8elDGNVhgdbH9NX38keG01gm35gUMr7Yjquzj8/xozvQ4eYVnGzyoZ/Vgk0I5yfR1RpQWXBLuQwYBROHJj8IpdthuDelcBNi8XkRS5U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jpiecuch.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=lvZt9zQc; arc=none smtp.client-ip=209.85.128.73 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--jpiecuch.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="lvZt9zQc" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-486fa07f2bbso79102635e9.2 for ; Tue, 28 Apr 2026 06:00:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1777381223; x=1777986023; darn=lists.linux.dev; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=FTVdVD5mINKkDtc8pjzLtIeyaI54xQ8u+57++otcEqs=; b=lvZt9zQcTz+0e+bnHiNtF5/V80yBUVVH7wHkDCnIFZWATlu0Q8nF2Pn1ikhusfUFQ2 sou9bHvSbgDiYgEBFU/fYSBmpYoxnKwlGraZWQ/YX+VqHGrPft3CX9FZLC/K4v8urdXM 1pxIytgAXTkNCuk2/kPcXyuSavUWTVhY8Q0j3PJjP/BjupWI9oDQoZRmEIhgZoFyICth p7X0yo+3HbATZhKA1drd4keuEbJYUNGRIWA2S5EI/hAlbqFWpPXiTPdM8EGG5cWDqb+D PMMX8LjNbpqL9D8pro6+G4e5qZZFX/pxVB287XyLI2m6NkM0BQtLvGf8Bm3GR2RpXKFf cZvA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777381223; x=1777986023; 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=FTVdVD5mINKkDtc8pjzLtIeyaI54xQ8u+57++otcEqs=; b=HO750sSnRIITyl6P8v87/pAZwl96tK/hxiss2HmL5yq0DNEudEL1EgVARQQVwcMZs5 hddkSirkZA7MPSX3mHhE/8QxErU6Prwq36ep+g0W9ZUQfpzItdk21sRwmFWBORWV2uiP wnvHUQ5lyoOPG6gfOaQvp8UpVMbprMUO7KiRdOwq/WwtCXtVc2iEHWkh8atLBvxFvAat B2hrH/wFCFNEQVdN/tm0Ywd2Omkdx2cIywtGGsP20CUr4Z9AUbm9dJ2vD3CICIT7R+4f EP2oqvOGPXODILOahz51RmO2l1LHRVnvdvk3r8stGBrj25RDFtHObmKdYq+DEWdB2mHE 4xsw== X-Gm-Message-State: AOJu0Yz59ff2CsYdYo6RVD+keqaXhsn8v9VQ1KZxJtSfH0D33TYzg7FF 8ssa3g1MQa6D64YDV5rj2f3yvVK7UcOLz54TftgHoOSXJ6PiBQbcG8Jhx6wn4BM1z+zySpivcxR /4aAWIsbSpmre6A== X-Received: from wmth18.prod.google.com ([2002:a05:600c:8b72:b0:48a:55cc:4954]) (user=jpiecuch job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:1d0a:b0:488:a824:fe04 with SMTP id 5b1f17b1804b1-48a77b1e893mr50478545e9.26.1777381223250; Tue, 28 Apr 2026 06:00:23 -0700 (PDT) Date: Tue, 28 Apr 2026 13:00:22 +0000 In-Reply-To: <20260424172721.3458520-8-tj@kernel.org> Precedence: bulk X-Mailing-List: sched-ext@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260424172721.3458520-1-tj@kernel.org> <20260424172721.3458520-8-tj@kernel.org> X-Mailer: aerc 0.21.0-0-g5549850facc2 Message-ID: Subject: Re: [PATCH 07/17] sched_ext: Add topological CPU IDs (cids) From: Kuba Piecuch To: Tejun Heo , David Vernet , Andrea Righi , Changwoo Min Cc: , , , Cheng-Yang Chou , Zhao Mengmeng Content-Type: text/plain; charset="UTF-8" Hi Tejun, Relaying a minor finding from Sashiko's review: https://sashiko.dev/#/patchset/20260424172721.3458520-1-tj%40kernel.org Might also be worth having a look at the findings for other patches in the series. > @@ -6727,6 +6728,16 @@ static void scx_root_enable_workfn(struct kthread_work *work) > */ > cpus_read_lock(); > > + /* > + * Build the cid mapping before publishing scx_root. The cid kfuncs > + * dereference the cid arrays unconditionally once scx_prog_sched() > + * returns non-NULL; the rcu_assign_pointer() below pairs with their > + * rcu_dereference() to make the populated arrays visible. > + */ > + ret = scx_cid_init(sch); > + if (ret) > + goto err_disable; > + Are we missing cpus_read_unlock() on the error path here? Thanks, Kuba