From nobody Tue Feb 10 19:47:39 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1518564943550675.4499686220817; Tue, 13 Feb 2018 15:35:43 -0800 (PST) Received: from localhost ([::1]:34314 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1elk6v-000891-HF for importer@patchew.org; Tue, 13 Feb 2018 18:35:41 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43379) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1elk4z-0006m7-58 for qemu-devel@nongnu.org; Tue, 13 Feb 2018 18:33:44 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1elk4w-0003Yq-Mv for qemu-devel@nongnu.org; Tue, 13 Feb 2018 18:33:39 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53890) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1elk4u-0003UE-4B; Tue, 13 Feb 2018 18:33:36 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 540505D68B; Tue, 13 Feb 2018 23:33:35 +0000 (UTC) Received: from red.redhat.com (ovpn-122-122.rdu2.redhat.com [10.10.122.122]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6E0D660BE5; Tue, 13 Feb 2018 23:33:34 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Date: Tue, 13 Feb 2018 17:33:24 -0600 Message-Id: <20180213233324.5096-3-eblake@redhat.com> In-Reply-To: <20180213233324.5096-1-eblake@redhat.com> References: <20180213233324.5096-1-eblake@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Tue, 13 Feb 2018 23:33:35 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH 2/2] qcow2: Prefer 'entries' over 'size' during cache creation X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , berto@igalia.com, qemu-block@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Using 'size' for anything other than bytes is difficult to reason about; let's rename entries related to the number of entries in a cache accordingly. Signed-off-by: Eric Blake --- block/qcow2.h | 4 ++-- block/qcow2.c | 21 +++++++++++---------- 2 files changed, 13 insertions(+), 12 deletions(-) diff --git a/block/qcow2.h b/block/qcow2.h index 883802241fb..0daf8e6d6f8 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -68,10 +68,10 @@ #define MAX_CLUSTER_BITS 21 /* Must be at least 2 to cover COW */ -#define MIN_L2_CACHE_SIZE 2 /* cache entries */ +#define MIN_L2_CACHE_ENTRIES 2 /* Must be at least 4 to cover all cases of refcount table growth */ -#define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */ +#define MIN_REFCOUNT_CACHE_ENTRIES 4 /* Whichever is more */ #define DEFAULT_L2_CACHE_CLUSTERS 8 /* clusters */ diff --git a/block/qcow2.c b/block/qcow2.c index 288b5299d80..f25c33df1d1 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -843,6 +843,7 @@ static int qcow2_update_options_prepare(BlockDriverStat= e *bs, const char *opt_overlap_check, *opt_overlap_check_template; int overlap_check_template =3D 0; uint64_t l2_cache_size, l2_cache_entry_size, refcount_cache_size; + uint64_t l2_cache_entries, refcount_cache_entries; int i; const char *encryptfmt; QDict *encryptopts =3D NULL; @@ -869,21 +870,21 @@ static int qcow2_update_options_prepare(BlockDriverSt= ate *bs, goto fail; } - l2_cache_size /=3D l2_cache_entry_size; - if (l2_cache_size < MIN_L2_CACHE_SIZE) { - l2_cache_size =3D MIN_L2_CACHE_SIZE; + l2_cache_entries =3D l2_cache_size / l2_cache_entry_size; + if (l2_cache_entries < MIN_L2_CACHE_ENTRIES) { + l2_cache_entries =3D MIN_L2_CACHE_ENTRIES; } - if (l2_cache_size > INT_MAX) { + if (l2_cache_entries > INT_MAX) { error_setg(errp, "L2 cache size too big"); ret =3D -EINVAL; goto fail; } - refcount_cache_size /=3D s->cluster_size; - if (refcount_cache_size < MIN_REFCOUNT_CACHE_SIZE) { - refcount_cache_size =3D MIN_REFCOUNT_CACHE_SIZE; + refcount_cache_entries =3D refcount_cache_size / s->cluster_size; + if (refcount_cache_entries < MIN_REFCOUNT_CACHE_ENTRIES) { + refcount_cache_entries =3D MIN_REFCOUNT_CACHE_ENTRIES; } - if (refcount_cache_size > INT_MAX) { + if (refcount_cache_entries > INT_MAX) { error_setg(errp, "Refcount cache size too big"); ret =3D -EINVAL; goto fail; @@ -908,9 +909,9 @@ static int qcow2_update_options_prepare(BlockDriverStat= e *bs, } r->l2_slice_size =3D l2_cache_entry_size / sizeof(uint64_t); - r->l2_table_cache =3D qcow2_cache_create(bs, l2_cache_size, + r->l2_table_cache =3D qcow2_cache_create(bs, l2_cache_entries, l2_cache_entry_size); - r->refcount_block_cache =3D qcow2_cache_create(bs, refcount_cache_size, + r->refcount_block_cache =3D qcow2_cache_create(bs, refcount_cache_entr= ies, s->cluster_size); if (r->l2_table_cache =3D=3D NULL || r->refcount_block_cache =3D=3D NU= LL) { error_setg(errp, "Could not allocate metadata caches"); --=20 2.14.3