From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792456025; b=fi4d6jywLn6r/bNKrspWboJaqwFdD+PB3dhKzAi2Z9I1dXwk/mOogKwMhGZaNM61jKBK 4I3KKZfjQffwxyhZxOl3+N/+ns4aeu+q7cesI/soDM9tmXFmTzGh97rbF1AHPzR9VEWhD fEvwugysjCD+aFJoy9jB1uvN2irhpXl0kd5Y+dCxwPgZr+dfCz1s/mO3e84jUwEYeEDR1 Z09Oa7uQT26/jRD79FxnsQz0oT89s9ZQlFoeh3zPkev6X9HZ62Fd1mUZnxXm2vAKH1tkV OgxIFdiQb+TwDVUgSQoJMBBoDZiFfJpq35EIHNom+UG52OF0oH+1EAZIM27u5X4kpNw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792456025; h=Received:DKIM-Signature:Date:Message-ID:From:To:Cc:Subject: In-Reply-To:References; bh=B3F7kA1Dq0BTEFmIKNS4VjfCfEEYVS0La+GUC2XgmTY=; b=v9GnnkcT2kVH4uq34bqc2EfBNkn4DIyWn/2lyPV7/js2BiEHxo3a6oP046aBTnNPcHHQ YOTlqsajB2maxjpx2g3gJhTnDsaO4na0iNSmcSrIsOwKGsQcJEXjEt6ZF0x963RGwwC5j RwgT17IpQzbMYJKaVXXCi7EUHF25vKUpSBvUtZLsl8I5daZ8owlEzddr+LKZar0r5FwTM F5sa+fxA2D6XiWLmkX9swIN+jCPbtezOYjAOvE2daaighAiHcDz1YxENbJRjcnic7dej+ lstTO8uXABbkprTkmA7fnZBIFs3bIz+Qdjo1SvfC7ukGnv4vk5ZMUgk1D8VWVC2Zt3w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=g9zJX4iz; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2D1EE606A31B; Tue, 20 Oct 2026 00:27:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=g9zJX4iz Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9B53A1F000C5; Tue, 20 Oct 2026 00:27:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792456024; bh=B3F7kA1Dq0BTEFmIKNS4VjfCfEEYVS0La+GUC2XgmTY=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=g9zJX4izF01bCwJidOuWWw6Rf+k7Qq3u17asgSBpTsRN0NvCriOVwH3S32h6IWXZs 8MOMDudO0Zf0Y7Vo8z66qGUO37Uj4nQYSjpdPZUcGbvTj3HLEiqA5HuRtV1c+wKWZQ ht48pYPupekUlR+G25ayUvapYdZhd7NYadGMzQruOPn4F4LglvbxKk1KoeEDDbVaoF SeO0baEuPiXZHGU/jrx8b3kXcOkKiVXW4LhionZVVq3la3vi8Esat0DO0oxrrAXOAV 2Rf0ierOamtP1j1ybwx5q/ISc92IpvSRSbmmMbXeA5u1zT/vTchBnx+AV+5VweT8GL cf1AVlLaZk05w== Date: Mon, 19 Oct 2026 14:27:03 -1000 Message-ID: <08cac02c604dd73ef96fc92eb29d692b@kernel.org> From: Tejun Heo To: Andrea Righi Cc: David Vernet , Changwoo Min , Emil Tsalapatis , sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 sched_ext/for-7.4] sched_ext: Queue the kick_sync wait from set_next_task_scx() In-Reply-To: <20261018162415.55913-1-arighi@nvidia.com> References: <20261018162415.55913-1-arighi@nvidia.com> X-Mailing-List: sched-ext@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list Applied to sched_ext/for-7.4-fixes. A few follow-ups: - With proxy exec, __schedule() can call set_next_task() twice on a repicked donor (SNT_REPICK, then SNT_PICK), which queues kick_sync_bal_cb twice. When it's alone on the list, it ends up linked to itself and the wait runs twice. - The foreign CPU check in kick_sync_wait_bal_cb() looks unreachable now. - Not from this patch, but maybe_queue_balance_callback() clears SCX_RQ_BAL_CB_PENDING when queueing, so a proxy exec zap leaves the deferred work unscheduled until the next wakeup or deferred request on the CPU. Thanks. -- tejun