From patchwork Wed Mar 13 08:15:02 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13591112 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 04A8F1B967 for ; Wed, 13 Mar 2024 08:15:15 +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=1710317717; cv=none; b=mavNDZezIyMEpCr7MZtxbfXjtpJIV4K7qOKDCCESFNf1yNCuLnn//tSo/wHdl1Z1cBBfhuQAvm4a4+PlKbt3NzJ4AgnAf1RyV4eFEnjyamVlBWVilDgLJoYmnFrEPSJBhNEupBFNvCWZB/Od9spCD51sTXknD9s+zpcgp9dvw54= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710317717; c=relaxed/simple; bh=nEffeaEkUXeL9ZZoT5q8k9bvL4SIKdrRskLsclcByxU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EdUf/1ZzrEDZRTSgaKTNECMH1da3zwDe7KIjqUrAAde77X7jMkTLfjYbF5iEjjvn+a/3VCW8PoxqVkbcYRguMfFa7iAZOkpUChO3pLqxII8i79lpprW7k7vogKpKDf/Wm5XBnNwrMJ8JCxU46d0vQVrbW6uEVyFbyxgLrW5nX0c= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none 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=UdTlpb3v; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none 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="UdTlpb3v" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1710317714; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WGiwFYhlQwAkAcK9KSYTrO5XDHNnn5GT+CKnu+I/Sm8=; b=UdTlpb3vdiu/wiW+IfSx3O8rSBFYP3DRvHPON9jhzqW3vU6CXZ4WhFi/9wf+HCewW5/cHP eOXt8PMDclNii2vFIqIoW/gPwdubLzy/hHstuXoPYeS6kesqS3lU2X2I5h3FI+q94Leup/ 7arwDBS9wxKeRblEU2yIGcux2a3Udnc= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-583-iPBGcg6VMCGu5FCxtsf5cQ-1; Wed, 13 Mar 2024 04:15:10 -0400 X-MC-Unique: iPBGcg6VMCGu5FCxtsf5cQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id 06070380390D; Wed, 13 Mar 2024 08:15:10 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.42.28.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id 310F53C23; Wed, 13 Mar 2024 08:15:09 +0000 (UTC) From: David Howells To: Marc Dionne Cc: David Howells , Christian Brauner , linux-afs@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/2] afs: Don't cache preferred address Date: Wed, 13 Mar 2024 08:15:02 +0000 Message-ID: <20240313081505.3060173-2-dhowells@redhat.com> In-Reply-To: <20240313081505.3060173-1-dhowells@redhat.com> References: <20240313081505.3060173-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.1 In the AFS fileserver rotation algorithm, don't cache the preferred address for the server as that will override the explicit preference if a non-preferred address responds first. Fixes: 495f2ae9e355 ("afs: Fix fileserver rotation") Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org --- fs/afs/rotate.c | 21 ++++----------------- 1 file changed, 4 insertions(+), 17 deletions(-) diff --git a/fs/afs/rotate.c b/fs/afs/rotate.c index 700a27bc8c25..ed04bd1eeae8 100644 --- a/fs/afs/rotate.c +++ b/fs/afs/rotate.c @@ -602,6 +602,8 @@ bool afs_select_fileserver(struct afs_operation *op) goto wait_for_more_probe_results; alist = op->estate->addresses; + best_prio = -1; + addr_index = 0; for (i = 0; i < alist->nr_addrs; i++) { if (alist->addrs[i].prio > best_prio) { addr_index = i; @@ -609,9 +611,7 @@ bool afs_select_fileserver(struct afs_operation *op) } } - addr_index = READ_ONCE(alist->preferred); - if (!test_bit(addr_index, &set)) - addr_index = __ffs(set); + alist->preferred = addr_index; op->addr_index = addr_index; set_bit(addr_index, &op->addr_tried); @@ -656,12 +656,6 @@ bool afs_select_fileserver(struct afs_operation *op) next_server: trace_afs_rotate(op, afs_rotate_trace_next_server, 0); _debug("next"); - ASSERT(op->estate); - alist = op->estate->addresses; - if (op->call_responded && - op->addr_index != READ_ONCE(alist->preferred) && - test_bit(alist->preferred, &op->addr_tried)) - WRITE_ONCE(alist->preferred, op->addr_index); op->estate = NULL; goto pick_server; @@ -690,14 +684,7 @@ bool afs_select_fileserver(struct afs_operation *op) failed: trace_afs_rotate(op, afs_rotate_trace_failed, 0); op->flags |= AFS_OPERATION_STOP; - if (op->estate) { - alist = op->estate->addresses; - if (op->call_responded && - op->addr_index != READ_ONCE(alist->preferred) && - test_bit(alist->preferred, &op->addr_tried)) - WRITE_ONCE(alist->preferred, op->addr_index); - op->estate = NULL; - } + op->estate = NULL; _leave(" = f [failed %d]", afs_op_error(op)); return false; }