Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758351Ab0LMQ7g (ORCPT ); Mon, 13 Dec 2010 11:59:36 -0500 Received: from mx1.redhat.com ([209.132.183.28]:5549 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758315Ab0LMQ7f (ORCPT ); Mon, 13 Dec 2010 11:59:35 -0500 Date: Mon, 13 Dec 2010 11:59:26 -0500 From: Vivek Goyal To: Gui Jianfeng Cc: Jens Axboe , Corrado Zoccolo , Chad Talbott , Nauman Rafique , Divyesh Shah , linux kernel mailing list Subject: Re: [PATCH 2/8 v2] cfq-iosched: Introduce cfq_entity for CFQ group Message-ID: <20101213165925.GF20454@redhat.com> References: <4CDF7BC5.9080803@cn.fujitsu.com> <4CDF9CC6.2040106@cn.fujitsu.com> <20101115165319.GI30792@redhat.com> <4CE2718C.6010406@kernel.dk> <4D01C6AB.9040807@cn.fujitsu.com> <4D057A81.1000901@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4D057A81.1000901@cn.fujitsu.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4752 Lines: 147 On Mon, Dec 13, 2010 at 09:44:33AM +0800, Gui Jianfeng wrote: > Introduce cfq_entity for CFQ group > > Signed-off-by: Gui Jianfeng > --- > block/cfq-iosched.c | 113 ++++++++++++++++++++++++++++++-------------------- > 1 files changed, 68 insertions(+), 45 deletions(-) > > diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c > index 9b07a24..91e9833 100644 > --- a/block/cfq-iosched.c > +++ b/block/cfq-iosched.c > @@ -1,5 +1,5 @@ > /* > - * CFQ, or complete fairness queueing, disk scheduler. > + * Cfq, or complete fairness queueing, disk scheduler. Is this really required? > * > * Based on ideas from a previously unfinished io > * scheduler (round robin per-process disk scheduling) and Andrea Arcangeli. > @@ -73,7 +73,8 @@ static DEFINE_IDA(cic_index_ida); > #define cfq_class_rt(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_RT) > > #define sample_valid(samples) ((samples) > 80) > -#define rb_entry_cfqg(node) rb_entry((node), struct cfq_group, rb_node) > +#define rb_entry_entity(node) rb_entry((node), struct cfq_entity,\ > + rb_node) > > /* > * Most of our rbtree usage is for sorting with min extraction, so > @@ -102,6 +103,11 @@ struct cfq_entity { > struct rb_node rb_node; > /* service_tree key, represent the position on the tree */ > unsigned long rb_key; > + > + /* group service_tree key */ > + u64 vdisktime; > + bool is_group_entity; > + unsigned int weight; > }; > > /* > @@ -183,12 +189,8 @@ enum wl_type_t { > > /* This is per cgroup per device grouping structure */ > struct cfq_group { > - /* group service_tree member */ > - struct rb_node rb_node; > - > - /* group service_tree key */ > - u64 vdisktime; > - unsigned int weight; > + /* cfq group sched entity */ > + struct cfq_entity cfqe; > > /* number of cfqq currently on this group */ > int nr_cfqq; > @@ -315,12 +317,21 @@ struct cfq_data { > static inline struct cfq_queue * > cfqq_of_entity(struct cfq_entity *cfqe) > { > - if (cfqe) > + if (cfqe && !cfqe->is_group_entity) > return container_of(cfqe, struct cfq_queue, > cfqe); can be single line above. I think came from previous patch. > return NULL; > } > > +static inline struct cfq_group * > +cfqg_of_entity(struct cfq_entity *cfqe) > +{ > + if (cfqe && cfqe->is_group_entity) > + return container_of(cfqe, struct cfq_group, > + cfqe); No need to split line. > + return NULL; > +} > + > static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd); > > static struct cfq_rb_root *service_tree_for(struct cfq_group *cfqg, > @@ -548,12 +559,12 @@ cfq_prio_to_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) > return cfq_prio_slice(cfqd, cfq_cfqq_sync(cfqq), cfqq->ioprio); > } > > -static inline u64 cfq_scale_slice(unsigned long delta, struct cfq_group *cfqg) > +static inline u64 cfq_scale_slice(unsigned long delta, struct cfq_entity *cfqe) > { > u64 d = delta << CFQ_SERVICE_SHIFT; > > d = d * BLKIO_WEIGHT_DEFAULT; > - do_div(d, cfqg->weight); > + do_div(d, cfqe->weight); > return d; > } > > @@ -578,11 +589,11 @@ static inline u64 min_vdisktime(u64 min_vdisktime, u64 vdisktime) > static void update_min_vdisktime(struct cfq_rb_root *st) > { > u64 vdisktime = st->min_vdisktime; > - struct cfq_group *cfqg; > + struct cfq_entity *cfqe; > > if (st->left) { > - cfqg = rb_entry_cfqg(st->left); > - vdisktime = min_vdisktime(vdisktime, cfqg->vdisktime); > + cfqe = rb_entry_entity(st->left); > + vdisktime = min_vdisktime(vdisktime, cfqe->vdisktime); > } > > st->min_vdisktime = max_vdisktime(st->min_vdisktime, vdisktime); > @@ -613,8 +624,9 @@ static inline unsigned > cfq_group_slice(struct cfq_data *cfqd, struct cfq_group *cfqg) > { > struct cfq_rb_root *st = &cfqd->grp_service_tree; > + struct cfq_entity *cfqe = &cfqg->cfqe; > > - return cfq_target_latency * cfqg->weight / st->total_weight; > + return cfq_target_latency * cfqe->weight / st->total_weight; > } > > static inline void > @@ -777,13 +789,13 @@ static struct cfq_entity *cfq_rb_first(struct cfq_rb_root *root) > return NULL; > } > > -static struct cfq_group *cfq_rb_first_group(struct cfq_rb_root *root) > +static struct cfq_entity *cfq_rb_first_entity(struct cfq_rb_root *root) So now we have two functions. One cfq_rb_first() and one cfq_rb_first_entity() both returning cfq_entity*? This is confusing. Or you are getting rid of one in later patches. Why not make use of existing cfq_rb_first()? Thanks Vivek -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/