From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7352834404F for ; Thu, 4 Dec 2025 14:31:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764858698; cv=none; b=TLOOf7DaeHnNHh9g5P8KQg4Nf5LoQzs9B4LH+KB9wex2XdiboxxW5XevEnumpYAbVkjMATmMBuoPA4npsxRDHwZt28hxp7AwMLA25KHdcY6XM0PPxuolxKua+eOYif4EFkaFix3rui9noWnfoJb5rFCLfYuaU/NglnmeQVOMizg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764858698; c=relaxed/simple; bh=R78sldUOazBXzPCDPb8p0RSLSPfENLmEgQQ2hNMVnOA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=t0NgwuO88jQh16jU9Jw3ggBtiodGWkW1evGItaESbQI5BUiltSFgLn1fA5mLui5wg3NyifHsPjpm/DnYwIbLa7rtNGfFvnBYG2BpFV/wLQ7N9PbHcE+HsLEuIxKBdfLC/+ULCWRZVHYVEeOG2vxqjz0fj/N4Ts1Rw7DnDsV460k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=AQbV5xsB; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="AQbV5xsB" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1764858695; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=8svFyJFXxwthUnxYwg8b9pc9HtZrBQvHp0Eb3p2+C8w=; b=AQbV5xsBz863q5G5cnNTIJ/ofE5sdMSpdYUREHxN8oa9YxpQbhQixCjDvvyDsYjdyxouzf 9CQLHGj1Uii0GTxtHcwyXK74Us4IhH083EXYVqAY8MshotSsZpZtm35UVAgLzRt1ur7m7U 6iLQ25bBDtXLri7prz7LHSNnQHrSgC0= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-211-VUX6OVjbNZSz733o-nNyqQ-1; Thu, 04 Dec 2025 09:31:32 -0500 X-MC-Unique: VUX6OVjbNZSz733o-nNyqQ-1 X-Mimecast-MFC-AGG-ID: VUX6OVjbNZSz733o-nNyqQ_1764858690 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 6A94D1956096; Thu, 4 Dec 2025 14:31:29 +0000 (UTC) Received: from fedora (unknown [10.45.226.144]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id C8AFE180045B; Thu, 4 Dec 2025 14:31:25 +0000 (UTC) Received: by fedora (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Thu, 4 Dec 2025 15:31:28 +0100 (CET) Date: Thu, 4 Dec 2025 15:31:24 +0100 From: Oleg Nesterov To: Mateusz Guzik Cc: brauner@kernel.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, linux-mm@kvack.org, willy@infradead.org Subject: Re: [PATCH v2 2/2] pid: only take pidmap_lock once on alloc Message-ID: References: <20251203092851.287617-1-mjguzik@gmail.com> <20251203092851.287617-3-mjguzik@gmail.com> 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=us-ascii Content-Disposition: inline In-Reply-To: <20251203092851.287617-3-mjguzik@gmail.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 On 12/03, Mateusz Guzik wrote: > > It has an unintentional side effect of no longer issuing spurious > idr_preload() around idr_replace(). ^^^^^^^^^^^ Around pidfs_add_pid(). The extra idr_preload/end was added by commit 9698d5a483654 ("pidfs: rework inode number allocation") because pidfs_add_pid() used to call idr_alloc_cyclic(GFP_ATOMIC) too. The patch looks technically correct to me, so FWIW Reviewed-by: Oleg Nesterov