From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f171.google.com (mail-pd0-f171.google.com [209.85.192.171]) by kanga.kvack.org (Postfix) with ESMTP id ADC096B0038 for ; Tue, 16 Jun 2015 03:25:59 -0400 (EDT) Received: by pdbki1 with SMTP id ki1so8298597pdb.1 for ; Tue, 16 Jun 2015 00:25:59 -0700 (PDT) Received: from lgemrelse7q.lge.com (LGEMRELSE7Q.lge.com. [156.147.1.151]) by mx.google.com with ESMTP id ed4si170646pbd.248.2015.06.16.00.25.57 for ; Tue, 16 Jun 2015 00:25:58 -0700 (PDT) Date: Tue, 16 Jun 2015 16:28:06 +0900 From: Joonsoo Kim Subject: Re: [PATCH 7/7] slub: initial bulk free implementation Message-ID: <20150616072806.GC13125@js1304-P5Q-DELUXE> References: <20150615155053.18824.617.stgit@devil> <20150615155256.18824.42651.stgit@devil> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150615155256.18824.42651.stgit@devil> Sender: owner-linux-mm@kvack.org List-ID: To: Jesper Dangaard Brouer Cc: linux-mm@kvack.org, Christoph Lameter , Andrew Morton , netdev@vger.kernel.org, Alexander Duyck On Mon, Jun 15, 2015 at 05:52:56PM +0200, Jesper Dangaard Brouer wrote: > This implements SLUB specific kmem_cache_free_bulk(). SLUB allocator > now both have bulk alloc and free implemented. > > Play nice and reenable local IRQs while calling slowpath. > > Signed-off-by: Jesper Dangaard Brouer > --- > mm/slub.c | 32 +++++++++++++++++++++++++++++++- > 1 file changed, 31 insertions(+), 1 deletion(-) > > diff --git a/mm/slub.c b/mm/slub.c > index 98d0e6f73ec1..cc4f870677bb 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -2752,7 +2752,37 @@ EXPORT_SYMBOL(kmem_cache_free); > > void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) > { > - __kmem_cache_free_bulk(s, size, p); > + struct kmem_cache_cpu *c; > + struct page *page; > + int i; > + > + local_irq_disable(); > + c = this_cpu_ptr(s->cpu_slab); > + > + for (i = 0; i < size; i++) { > + void *object = p[i]; > + > + if (unlikely(!object)) > + continue; // HOW ABOUT BUG_ON()??? > + > + page = virt_to_head_page(object); > + BUG_ON(s != page->slab_cache); /* Check if valid slab page */ > + > + if (c->page == page) { > + /* Fastpath: local CPU free */ > + set_freepointer(s, object, c->freelist); > + c->freelist = object; > + } else { > + c->tid = next_tid(c->tid); > + local_irq_enable(); > + /* Slowpath: overhead locked cmpxchg_double_slab */ > + __slab_free(s, page, object, _RET_IP_); > + local_irq_disable(); > + c = this_cpu_ptr(s->cpu_slab); SLUB free path doesn't need to irq management in many cases although it uses cmpxchg_doule_slab. Is this really better than just calling __kmem_cache_free_bulk()? Thanks. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org