From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8BD05C433E6 for ; Tue, 5 Jan 2021 12:46:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 68AA2229F0 for ; Tue, 5 Jan 2021 12:46:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729367AbhAEMqU (ORCPT ); Tue, 5 Jan 2021 07:46:20 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:43127 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729268AbhAEMqT (ORCPT ); Tue, 5 Jan 2021 07:46:19 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1609850692; 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=agO6BYZemNkLWVbGRmMmpwdINpe6sn2yq73em0ndDn4=; b=cmfnRzsu1QMopJRreZXyNjLA/cPUrGnT1YWxBmcuwROnpF4lDMvcBMYFi+lILRFIx+LevZ DfyHZMeZ3n1rHPBUCa++kC+s+ht6zgcEhMh+5fuAgWJFCt0c5hEfaBXE+sG7vx2PodDhCf pMFECw8BoFyxWG9brLunTFbHI0Y9Ouw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-4-dCV6KwIJN86S9bbnoN2ykA-1; Tue, 05 Jan 2021 07:42:22 -0500 X-MC-Unique: dCV6KwIJN86S9bbnoN2ykA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 353A4BBF07; Tue, 5 Jan 2021 12:42:21 +0000 (UTC) Received: from localhost (ovpn-12-37.pek2.redhat.com [10.72.12.37]) by smtp.corp.redhat.com (Postfix) with ESMTP id A639F5D6CF; Tue, 5 Jan 2021 12:42:17 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Christoph Hellwig , Ming Lei Subject: [PATCH V2 1/6] block: manage bio slab cache by xarray Date: Tue, 5 Jan 2021 20:41:58 +0800 Message-Id: <20210105124203.3726599-2-ming.lei@redhat.com> In-Reply-To: <20210105124203.3726599-1-ming.lei@redhat.com> References: <20210105124203.3726599-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Managing bio slab cache via xarray by using slab cache size as xarray index, and storing 'struct bio_slab' instance into xarray. So code is simplified a lot, meantime it becomes more readable than before. Signed-off-by: Ming Lei --- block/bio.c | 114 ++++++++++++++++++++++------------------------------ 1 file changed, 48 insertions(+), 66 deletions(-) diff --git a/block/bio.c b/block/bio.c index 1f2cc1fbe283..f72d4783f6c5 100644 --- a/block/bio.c +++ b/block/bio.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include "blk.h" @@ -58,89 +59,80 @@ struct bio_slab { char name[8]; }; static DEFINE_MUTEX(bio_slab_lock); -static struct bio_slab *bio_slabs; -static unsigned int bio_slab_nr, bio_slab_max; +static DEFINE_XARRAY(bio_slabs); -static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size) +static struct bio_slab *create_bio_slab(unsigned int size) { - unsigned int sz = sizeof(struct bio) + extra_size; - struct kmem_cache *slab = NULL; - struct bio_slab *bslab, *new_bio_slabs; - unsigned int new_bio_slab_max; - unsigned int i, entry = -1; + struct bio_slab *bslab = kzalloc(sizeof(*bslab), GFP_KERNEL); - mutex_lock(&bio_slab_lock); - - i = 0; - while (i < bio_slab_nr) { - bslab = &bio_slabs[i]; + if (!bslab) + return NULL; - if (!bslab->slab && entry == -1) - entry = i; - else if (bslab->slab_size == sz) { - slab = bslab->slab; - bslab->slab_ref++; - break; - } - i++; + snprintf(bslab->name, sizeof(bslab->name), "bio-%d", size); + bslab->slab = kmem_cache_create(bslab->name, size, + ARCH_KMALLOC_MINALIGN, SLAB_HWCACHE_ALIGN, NULL); + if (!bslab->slab) { + kfree(bslab); + return NULL; } - if (slab) - goto out_unlock; - - if (bio_slab_nr == bio_slab_max && entry == -1) { - new_bio_slab_max = bio_slab_max << 1; - new_bio_slabs = krealloc(bio_slabs, - new_bio_slab_max * sizeof(struct bio_slab), - GFP_KERNEL); - if (!new_bio_slabs) - goto out_unlock; - bio_slab_max = new_bio_slab_max; - bio_slabs = new_bio_slabs; + bslab->slab_ref = 1; + bslab->slab_size = size; + + if (xa_err(xa_store(&bio_slabs, size, bslab, GFP_KERNEL))) { + kmem_cache_destroy(bslab->slab); + kfree(bslab); + return NULL; } - if (entry == -1) - entry = bio_slab_nr++; + return bslab; +} - bslab = &bio_slabs[entry]; +static inline unsigned int bs_bio_slab_size(struct bio_set *bs) +{ + return bs->front_pad + sizeof(struct bio) + + BIO_INLINE_VECS * sizeof(struct bio_vec); +} - snprintf(bslab->name, sizeof(bslab->name), "bio-%d", entry); - slab = kmem_cache_create(bslab->name, sz, ARCH_KMALLOC_MINALIGN, - SLAB_HWCACHE_ALIGN, NULL); - if (!slab) - goto out_unlock; +static struct kmem_cache *bio_find_or_create_slab(struct bio_set *bs) +{ + unsigned int size = bs_bio_slab_size(bs); + struct bio_slab *bslab; - bslab->slab = slab; - bslab->slab_ref = 1; - bslab->slab_size = sz; -out_unlock: + mutex_lock(&bio_slab_lock); + bslab = xa_load(&bio_slabs, size); + if (bslab) + bslab->slab_ref++; + else + bslab = create_bio_slab(size); mutex_unlock(&bio_slab_lock); - return slab; + + if (bslab) + return bslab->slab; + return NULL; } static void bio_put_slab(struct bio_set *bs) { struct bio_slab *bslab = NULL; - unsigned int i; + unsigned int slab_size = bs_bio_slab_size(bs); mutex_lock(&bio_slab_lock); - for (i = 0; i < bio_slab_nr; i++) { - if (bs->bio_slab == bio_slabs[i].slab) { - bslab = &bio_slabs[i]; - break; - } - } - + bslab = xa_load(&bio_slabs, slab_size); if (WARN(!bslab, KERN_ERR "bio: unable to find slab!\n")) goto out; + WARN_ON_ONCE(bslab->slab != bs->bio_slab); + WARN_ON(!bslab->slab_ref); if (--bslab->slab_ref) goto out; + xa_erase(&bio_slabs, slab_size); + kmem_cache_destroy(bslab->slab); - bslab->slab = NULL; + kfree(bslab); out: mutex_unlock(&bio_slab_lock); @@ -1579,15 +1571,13 @@ int bioset_init(struct bio_set *bs, unsigned int front_pad, int flags) { - unsigned int back_pad = BIO_INLINE_VECS * sizeof(struct bio_vec); - bs->front_pad = front_pad; spin_lock_init(&bs->rescue_lock); bio_list_init(&bs->rescue_list); INIT_WORK(&bs->rescue_work, bio_alloc_rescue); - bs->bio_slab = bio_find_or_create_slab(front_pad + back_pad); + bs->bio_slab = bio_find_or_create_slab(bs); if (!bs->bio_slab) return -ENOMEM; @@ -1651,16 +1641,8 @@ static void __init biovec_init_slabs(void) static int __init init_bio(void) { - bio_slab_max = 2; - bio_slab_nr = 0; - bio_slabs = kcalloc(bio_slab_max, sizeof(struct bio_slab), - GFP_KERNEL); - BUILD_BUG_ON(BIO_FLAG_LAST > BVEC_POOL_OFFSET); - if (!bio_slabs) - panic("bio: can't allocate bios\n"); - bio_integrity_init(); biovec_init_slabs(); -- 2.28.0