Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758130AbZFICM3 (ORCPT ); Mon, 8 Jun 2009 22:12:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757642AbZFICKl (ORCPT ); Mon, 8 Jun 2009 22:10:41 -0400 Received: from mx2.redhat.com ([66.187.237.31]:44015 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757420AbZFICKd (ORCPT ); Mon, 8 Jun 2009 22:10:33 -0400 From: Vivek Goyal To: linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org, dm-devel@redhat.com, jens.axboe@oracle.com, nauman@google.com, dpshah@google.com, lizf@cn.fujitsu.com, mikew@google.com, fchecconi@gmail.com, paolo.valente@unimore.it, ryov@valinux.co.jp, fernando@oss.ntt.co.jp, s-uchida@ap.jp.nec.com, taka@valinux.co.jp, guijianfeng@cn.fujitsu.com, jmoyer@redhat.com, dhaval@linux.vnet.ibm.com, balbir@linux.vnet.ibm.com, righi.andrea@gmail.com, m-ikeda@ds.jp.nec.com, jbaron@redhat.com Cc: agk@redhat.com, snitzer@redhat.com, vgoyal@redhat.com, akpm@linux-foundation.org, peterz@infradead.org Subject: [PATCH 18/19] io-controller: Debug hierarchical IO scheduling Date: Mon, 8 Jun 2009 22:09:01 -0400 Message-Id: <1244513342-11758-19-git-send-email-vgoyal@redhat.com> In-Reply-To: <1244513342-11758-1-git-send-email-vgoyal@redhat.com> References: <1244513342-11758-1-git-send-email-vgoyal@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 20556 Lines: 681 o Littile debugging aid for hierarchical IO scheduling. o Enabled under CONFIG_DEBUG_GROUP_IOSCHED o Currently it outputs more debug messages in blktrace output which helps a great deal in debugging in hierarchical setup. It also creates additional cgroup interfaces io.disk_queue and io.disk_dequeue to output some more debugging data. Signed-off-by: Vivek Goyal --- block/Kconfig.iosched | 10 ++- block/as-iosched.c | 50 ++++++--- block/elevator-fq.c | 285 ++++++++++++++++++++++++++++++++++++++++++++++++- block/elevator-fq.h | 26 +++++ 4 files changed, 347 insertions(+), 24 deletions(-) diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched index 0677099..79f188c 100644 --- a/block/Kconfig.iosched +++ b/block/Kconfig.iosched @@ -140,6 +140,14 @@ config TRACK_ASYNC_CONTEXT request, original owner of the bio is decided by using io tracking patches otherwise we continue to attribute the request to the submitting thread. -endmenu +config DEBUG_GROUP_IOSCHED + bool "Debug Hierarchical Scheduling support" + depends on CGROUPS && GROUP_IOSCHED + default n + ---help--- + Enable some debugging hooks for hierarchical scheduling support. + Currently it just outputs more information in blktrace output. + +endmenu endif diff --git a/block/as-iosched.c b/block/as-iosched.c index b0c66e4..735d055 100644 --- a/block/as-iosched.c +++ b/block/as-iosched.c @@ -78,6 +78,7 @@ enum anticipation_status { }; struct as_queue { + struct io_queue *ioq; /* * requests (as_rq s) are present on both sort_list and fifo_list */ @@ -162,6 +163,17 @@ enum arq_state { #define RQ_STATE(rq) ((enum arq_state)(rq)->elevator_private2) #define RQ_SET_STATE(rq, state) ((rq)->elevator_private2 = (void *) state) +#ifdef CONFIG_DEBUG_GROUP_IOSCHED +#define as_log_asq(ad, asq, fmt, args...) \ +{ \ + blk_add_trace_msg((ad)->q, "as %s " fmt, \ + ioq_to_io_group((asq)->ioq)->path, ##args); \ +} +#else +#define as_log_asq(ad, asq, fmt, args...) \ + blk_add_trace_msg((ad)->q, "as " fmt, ##args) +#endif + #define as_log(ad, fmt, args...) \ blk_add_trace_msg((ad)->q, "as " fmt, ##args) @@ -225,7 +237,7 @@ static void as_save_batch_context(struct as_data *ad, struct as_queue *asq) } out: - as_log(ad, "save batch: dir=%c time_left=%d changed_batch=%d" + as_log_asq(ad, asq, "save batch: dir=%c time_left=%d changed_batch=%d" " new_batch=%d, antic_status=%d", ad->batch_data_dir ? 'R' : 'W', asq->current_batch_time_left, @@ -247,8 +259,8 @@ static void as_restore_batch_context(struct as_data *ad, struct as_queue *asq) asq->current_batch_time_left; /* restore asq batch_data_dir info */ ad->batch_data_dir = asq->saved_batch_data_dir; - as_log(ad, "restore batch: dir=%c time=%d reads_q=%d writes_q=%d" - " ad->antic_status=%d", + as_log_asq(ad, asq, "restore batch: dir=%c time=%d reads_q=%d" + " writes_q=%d ad->antic_status=%d", ad->batch_data_dir ? 'R' : 'W', asq->current_batch_time_left, asq->nr_queued[1], asq->nr_queued[0], @@ -277,8 +289,8 @@ static int as_expire_ioq(struct request_queue *q, void *sched_queue, int status = ad->antic_status; struct as_queue *asq = sched_queue; - as_log(ad, "as_expire_ioq slice_expired=%d, force=%d", slice_expired, - force); + as_log_asq(ad, asq, "as_expire_ioq slice_expired=%d, force=%d", + slice_expired, force); /* Forced expiry. We don't have a choice */ if (force) { @@ -1019,9 +1031,10 @@ static void update_write_batch(struct as_data *ad, struct request *rq) if (write_time < 0) write_time = 0; - as_log(ad, "upd write: write_time=%d batch=%d write_batch_idled=%d" - " current_write_count=%d", write_time, batch, - asq->write_batch_idled, asq->current_write_count); + as_log_asq(ad, asq, "upd write: write_time=%d batch=%d" + " write_batch_idled=%d current_write_count=%d", + write_time, batch, asq->write_batch_idled, + asq->current_write_count); if (write_time > batch && !asq->write_batch_idled) { if (write_time > batch * 3) @@ -1038,7 +1051,7 @@ static void update_write_batch(struct as_data *ad, struct request *rq) if (asq->write_batch_count < 1) asq->write_batch_count = 1; - as_log(ad, "upd write count=%d", asq->write_batch_count); + as_log_asq(ad, asq, "upd write count=%d", asq->write_batch_count); } /* @@ -1057,7 +1070,7 @@ static void as_completed_request(struct request_queue *q, struct request *rq) goto out; } - as_log(ad, "complete: reads_q=%d writes_q=%d changed_batch=%d" + as_log_asq(ad, asq, "complete: reads_q=%d writes_q=%d changed_batch=%d" " new_batch=%d switch_queue=%d, dir=%c", asq->nr_queued[1], asq->nr_queued[0], ad->changed_batch, ad->new_batch, ad->switch_queue, @@ -1251,7 +1264,7 @@ static void as_move_to_dispatch(struct as_data *ad, struct request *rq) if (RQ_IOC(rq) && RQ_IOC(rq)->aic) atomic_inc(&RQ_IOC(rq)->aic->nr_dispatched); ad->nr_dispatched++; - as_log(ad, "dispatch req dir=%c nr_dispatched = %d", + as_log_asq(ad, asq, "dispatch req dir=%c nr_dispatched = %d", data_dir ? 'R' : 'W', ad->nr_dispatched); } @@ -1300,7 +1313,7 @@ static int as_dispatch_request(struct request_queue *q, int force) } asq->last_check_fifo[BLK_RW_ASYNC] = jiffies; - as_log(ad, "forced dispatch"); + as_log_asq(ad, asq, "forced dispatch"); return dispatched; } @@ -1314,7 +1327,7 @@ static int as_dispatch_request(struct request_queue *q, int force) || ad->antic_status == ANTIC_WAIT_REQ || ad->antic_status == ANTIC_WAIT_NEXT || ad->changed_batch) { - as_log(ad, "no dispatch. read_q=%d, writes_q=%d" + as_log_asq(ad, asq, "no dispatch. read_q=%d, writes_q=%d" " ad->antic_status=%d, changed_batch=%d," " switch_queue=%d new_batch=%d", asq->nr_queued[1], asq->nr_queued[0], ad->antic_status, ad->changed_batch, @@ -1333,7 +1346,7 @@ static int as_dispatch_request(struct request_queue *q, int force) goto fifo_expired; if (as_can_anticipate(ad, rq)) { - as_log(ad, "can_anticipate = 1"); + as_log_asq(ad, asq, "can_anticipate = 1"); as_antic_waitreq(ad); return 0; } @@ -1353,7 +1366,7 @@ static int as_dispatch_request(struct request_queue *q, int force) * data direction (read / write) */ - as_log(ad, "select a fresh batch and request"); + as_log_asq(ad, asq, "select a fresh batch and request"); if (reads) { BUG_ON(RB_EMPTY_ROOT(&asq->sort_list[BLK_RW_SYNC])); @@ -1369,7 +1382,7 @@ static int as_dispatch_request(struct request_queue *q, int force) ad->changed_batch = 1; } ad->batch_data_dir = BLK_RW_SYNC; - as_log(ad, "new batch dir is sync"); + as_log_asq(ad, asq, "new batch dir is sync"); rq = rq_entry_fifo(asq->fifo_list[BLK_RW_SYNC].next); asq->last_check_fifo[ad->batch_data_dir] = jiffies; goto dispatch_request; @@ -1394,7 +1407,7 @@ dispatch_writes: ad->new_batch = 0; } ad->batch_data_dir = BLK_RW_ASYNC; - as_log(ad, "new batch dir is async"); + as_log_asq(ad, asq, "new batch dir is async"); asq->current_write_count = asq->write_batch_count; asq->write_batch_idled = 0; rq = rq_entry_fifo(asq->fifo_list[BLK_RW_ASYNC].next); @@ -1457,7 +1470,7 @@ static void as_add_request(struct request_queue *q, struct request *rq) rq->elevator_private = as_get_io_context(q->node); asq->nr_queued[data_dir]++; - as_log(ad, "add a %c request read_q=%d write_q=%d", + as_log_asq(ad, asq, "add a %c request read_q=%d write_q=%d", data_dir ? 'R' : 'W', asq->nr_queued[1], asq->nr_queued[0]); @@ -1616,6 +1629,7 @@ static void *as_alloc_as_queue(struct request_queue *q, if (asq->write_batch_count < 2) asq->write_batch_count = 2; + asq->ioq = ioq; out: return asq; } diff --git a/block/elevator-fq.c b/block/elevator-fq.c index 207664d..207bdf1 100644 --- a/block/elevator-fq.c +++ b/block/elevator-fq.c @@ -117,6 +117,126 @@ static inline int iog_deleting(struct io_group *iog) return iog->deleting; } +static inline struct io_group *io_entity_to_iog(struct io_entity *entity) +{ + struct io_group *iog = NULL; + + BUG_ON(entity == NULL); + if (entity->my_sched_data != NULL) + iog = container_of(entity, struct io_group, entity); + return iog; +} + +/* Returns parent group of io group */ +static inline struct io_group *iog_parent(struct io_group *iog) +{ + struct io_group *piog; + + if (!iog->entity.sched_data) + return NULL; + + /* + * Not following entity->parent pointer as for top level groups + * this pointer is NULL. + */ + piog = container_of(iog->entity.sched_data, struct io_group, + sched_data); + return piog; +} + +#ifdef CONFIG_DEBUG_GROUP_IOSCHED +static void io_group_path(struct io_group *iog, char *buf, int buflen) +{ + unsigned short id = iog->iocg_id; + struct cgroup_subsys_state *css; + + rcu_read_lock(); + + if (!id) + goto out; + + css = css_lookup(&io_subsys, id); + if (!css) + goto out; + + if (!css_tryget(css)) + goto out; + + cgroup_path(css->cgroup, buf, buflen); + + css_put(css); + + rcu_read_unlock(); + return; +out: + rcu_read_unlock(); + buf[0] = '\0'; + return; +} + +/* + * An entity has been freshly added to active tree. Either it came from + * idle tree or it was not on any of the trees. Do the accounting. + */ +static inline void bfq_account_for_entity_addition(struct io_entity *entity) +{ + struct io_group *iog = io_entity_to_iog(entity); + + if (iog) { + struct elv_fq_data *efqd; + char path[128]; + + /* + * Keep track of how many times a group has been removed + * from active tree because it did not have any active + * backlogged ioq under it + */ + iog->queue++; + iog->queue_start = jiffies; + + /* Log group addition event */ + rcu_read_lock(); + efqd = rcu_dereference(iog->key); + if (efqd) { + io_group_path(iog, path, sizeof(path)); + elv_log(efqd, "add group=%s weight=%ld", path, + iog->entity.weight); + } + rcu_read_unlock(); + } +} + +/* + * An entity got removed from active tree and either went to idle tree or + * not is on any of the tree. Do the accouting + */ +static inline void bfq_account_for_entity_deletion(struct io_entity *entity) +{ + struct io_group *iog = io_entity_to_iog(entity); + + if (iog) { + struct elv_fq_data *efqd; + char path[128]; + + iog->dequeue++; + /* Keep a track of how long group was on active tree */ + iog->queue_duration += jiffies_to_msecs(jiffies - + iog->queue_start); + iog->queue_start = 0; + + /* Log group deletion event */ + rcu_read_lock(); + efqd = rcu_dereference(iog->key); + if (efqd) { + io_group_path(iog, path, sizeof(path)); + elv_log(efqd, "del group=%s weight=%ld", path, + iog->entity.weight); + } + rcu_read_unlock(); + } +} +#endif + #else /* GROUP_IOSCHED */ #define for_each_entity(entity) \ for (; entity != NULL; entity = NULL) @@ -139,6 +259,12 @@ static inline int iog_deleting(struct io_group *iog) /* In flat mode, root cgroup can't be deleted. */ return 0; } + +static inline struct io_group *io_entity_to_iog(struct io_entity *entity) +{ + return NULL; +} + #endif /* @@ -572,6 +698,7 @@ static void __bfq_activate_entity(struct io_entity *entity, int add_front) { struct io_sched_data *sd = entity->sched_data; struct io_service_tree *st = io_entity_service_tree(entity); + int newly_added = 0; if (entity == sd->active_entity) { BUG_ON(entity->tree != NULL); @@ -598,6 +725,7 @@ static void __bfq_activate_entity(struct io_entity *entity, int add_front) bfq_idle_extract(st, entity); entity->start = bfq_gt(st->vtime, entity->finish) ? st->vtime : entity->finish; + newly_added = 1; } else { /* * The finish time of the entity may be invalid, and @@ -610,6 +738,7 @@ static void __bfq_activate_entity(struct io_entity *entity, int add_front) BUG_ON(entity->on_st); entity->on_st = 1; + newly_added = 1; } st = __bfq_entity_update_prio(st, entity); @@ -647,6 +776,10 @@ static void __bfq_activate_entity(struct io_entity *entity, int add_front) bfq_calc_finish(entity, entity->budget); } bfq_active_insert(st, entity); +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + if (newly_added) + bfq_account_for_entity_addition(entity); +#endif } /** @@ -717,6 +850,9 @@ int __bfq_deactivate_entity(struct io_entity *entity, int requeue) BUG_ON(sd->active_entity == entity); BUG_ON(sd->next_active == entity); +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + bfq_account_for_entity_deletion(entity); +#endif return ret; } @@ -1209,6 +1345,67 @@ static int io_cgroup_disk_sectors_read(struct cgroup *cgroup, return 0; } +#ifdef CONFIG_DEBUG_GROUP_IOSCHED +static int io_cgroup_disk_queue_read(struct cgroup *cgroup, + struct cftype *cftype, struct seq_file *m) +{ + struct io_cgroup *iocg = NULL; + struct io_group *iog = NULL; + struct hlist_node *n; + + if (!cgroup_lock_live_group(cgroup)) + return -ENODEV; + + iocg = cgroup_to_io_cgroup(cgroup); + spin_lock_irq(&iocg->lock); + /* Loop through all the io groups and print statistics */ + hlist_for_each_entry_rcu(iog, n, &iocg->group_data, group_node) { + /* + * There might be groups which are not functional and + * waiting to be reclaimed upon cgoup deletion. + */ + if (iog->key) { + seq_printf(m, "%u %u %lu %lu\n", MAJOR(iog->dev), + MINOR(iog->dev), iog->queue, + iog->queue_duration); + } + } + spin_unlock_irq(&iocg->lock); + cgroup_unlock(); + + return 0; +} + +static int io_cgroup_disk_dequeue_read(struct cgroup *cgroup, + struct cftype *cftype, struct seq_file *m) +{ + struct io_cgroup *iocg = NULL; + struct io_group *iog = NULL; + struct hlist_node *n; + + if (!cgroup_lock_live_group(cgroup)) + return -ENODEV; + + iocg = cgroup_to_io_cgroup(cgroup); + spin_lock_irq(&iocg->lock); + /* Loop through all the io groups and print statistics */ + hlist_for_each_entry_rcu(iog, n, &iocg->group_data, group_node) { + /* + * There might be groups which are not functional and + * waiting to be reclaimed upon cgoup deletion. + */ + if (iog->key) { + seq_printf(m, "%u %u %lu\n", MAJOR(iog->dev), + MINOR(iog->dev), iog->dequeue); + } + } + spin_unlock_irq(&iocg->lock); + cgroup_unlock(); + + return 0; +} +#endif + /** * bfq_group_chain_alloc - allocate a chain of groups. * @bfqd: queue descriptor. @@ -1263,7 +1460,9 @@ struct io_group *io_group_chain_alloc(struct request_queue *q, void *key, } blk_init_request_list(&iog->rl); - +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + io_group_path(iog, iog->path, sizeof(iog->path)); +#endif if (leaf == NULL) { leaf = iog; prev = leaf; @@ -1766,6 +1965,16 @@ struct cftype bfqio_files[] = { .name = "disk_sectors", .read_seq_string = io_cgroup_disk_sectors_read, }, +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + { + .name = "disk_queue", + .read_seq_string = io_cgroup_disk_queue_read, + }, + { + .name = "disk_dequeue", + .read_seq_string = io_cgroup_disk_dequeue_read, + }, +#endif }; int iocg_populate(struct cgroup_subsys *subsys, struct cgroup *cgroup) @@ -2090,6 +2299,7 @@ struct cgroup_subsys io_subsys = { .destroy = iocg_destroy, .populate = iocg_populate, .subsys_id = io_subsys_id, + .use_id = 1, }; /* @@ -2380,6 +2590,22 @@ EXPORT_SYMBOL(elv_get_slice_idle); void elv_ioq_served(struct io_queue *ioq, bfq_service_t served) { entity_served(&ioq->entity, served, ioq->nr_sectors); + +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + { + struct elv_fq_data *efqd = ioq->efqd; + struct io_group *iog = ioq_to_io_group(ioq); + elv_log_ioq(efqd, ioq, "ioq served: QSt=0x%lx QSs=0x%lx" + " QTt=0x%lx QTs=0x%lx GTt=0x%lx " + " GTs=0x%lx rq_queued=%d", + served, ioq->nr_sectors, + ioq->entity.total_service, + ioq->entity.total_sector_service, + iog->entity.total_service, + iog->entity.total_sector_service, + ioq->nr_queued); + } +#endif } /* Tells whether ioq is queued in root group or not */ @@ -2847,10 +3073,30 @@ static void __elv_set_active_ioq(struct elv_fq_data *efqd, struct io_queue *ioq, if (ioq) { struct io_group *iog = ioq_to_io_group(ioq); elv_log_ioq(efqd, ioq, "set_active, busy=%d ioprio=%d" - " weight=%ld group_weight=%ld", + " weight=%ld rq_queued=%d group_weight=%ld", efqd->busy_queues, ioq->entity.ioprio, ioq->entity.weight, - iog_weight(iog)); + ioq->nr_queued, iog_weight(iog)); + +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + { + int nr_active = 0; + struct io_group *parent = NULL; + + parent = iog_parent(iog); + if (parent) + nr_active = elv_iog_nr_active(parent); + + elv_log_ioq(efqd, ioq, "set_active, ioq" + " nrgrps=%d QTt=0x%lx QTs=0x%lx GTt=0x%lx " + " GTs=0x%lx rq_queued=%d", nr_active, + ioq->entity.total_service, + ioq->entity.total_sector_service, + iog->entity.total_service, + iog->entity.total_sector_service, + ioq->nr_queued); + } +#endif ioq->slice_end = 0; elv_clear_ioq_wait_request(ioq); @@ -2927,12 +3173,26 @@ void elv_add_ioq_busy(struct elv_fq_data *efqd, struct io_queue *ioq) { BUG_ON(elv_ioq_busy(ioq)); BUG_ON(ioq == efqd->active_queue); - elv_log_ioq(efqd, ioq, "add to busy"); elv_activate_ioq(ioq, 0); elv_mark_ioq_busy(ioq); efqd->busy_queues++; if (elv_ioq_class_rt(ioq)) efqd->busy_rt_queues++; + +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + { + struct io_group *iog = ioq_to_io_group(ioq); + elv_log_ioq(efqd, ioq, "add to busy: QTt=0x%lx QTs=0x%lx" + " ioq grp=%s GTt=0x%lx GTs=0x%lx rq_queued=%d", + ioq->entity.total_service, + ioq->entity.total_sector_service, + iog->entity.total_service, + iog->entity.total_sector_service, + ioq->nr_queued); + } +#else + elv_log_ioq(efqd, ioq, "add to busy"); +#endif } void elv_del_ioq_busy(struct elevator_queue *e, struct io_queue *ioq, @@ -2942,7 +3202,21 @@ void elv_del_ioq_busy(struct elevator_queue *e, struct io_queue *ioq, BUG_ON(!elv_ioq_busy(ioq)); BUG_ON(ioq->nr_queued); +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + { + struct io_group *iog = ioq_to_io_group(ioq); + elv_log_ioq(efqd, ioq, "del from busy: QTt=0x%lx " + "QTs=0x%lx ioq GTt=0x%lx GTs=0x%lx " + "rq_queued=%d", + ioq->entity.total_service, + ioq->entity.total_sector_service, + iog->entity.total_service, + iog->entity.total_sector_service, + ioq->nr_queued); + } +#else elv_log_ioq(efqd, ioq, "del from busy"); +#endif elv_clear_ioq_busy(ioq); BUG_ON(efqd->busy_queues == 0); efqd->busy_queues--; @@ -3179,6 +3453,7 @@ void elv_ioq_request_add(struct request_queue *q, struct request *rq) elv_ioq_update_io_thinktime(ioq); elv_ioq_update_idle_window(q->elevator, ioq, rq); + elv_log_ioq(efqd, ioq, "add rq: rq_queued=%d", ioq->nr_queued); if (ioq == elv_active_ioq(q->elevator)) { /* @@ -3412,7 +3687,7 @@ void *elv_fq_select_ioq(struct request_queue *q, int force) } /* We are waiting for this queue to become busy before it expires.*/ - if (efqd->fairness && elv_ioq_wait_busy(ioq)) { + if (elv_ioq_wait_busy(ioq)) { ioq = NULL; goto keep_queue; } diff --git a/block/elevator-fq.h b/block/elevator-fq.h index ff409ec..b5cff90 100644 --- a/block/elevator-fq.h +++ b/block/elevator-fq.h @@ -251,6 +251,23 @@ struct io_group { /* request list associated with the group */ struct request_list rl; + +#ifdef CONFIG_DEBUG_GROUP_IOSCHED + /* How many times this group has been added to active tree */ + unsigned long queue; + + /* How long this group remained on active tree, in ms */ + unsigned long queue_duration; + + /* When was this group added to active tree */ + unsigned long queue_start; + + /* How many times this group has been removed from active tree */ + unsigned long dequeue; + + /* Store cgroup path */ + char path[128]; +#endif }; struct io_policy_node { @@ -353,9 +370,18 @@ extern int elv_slice_idle; extern int elv_slice_async; /* Logging facilities. */ +#ifdef CONFIG_DEBUG_GROUP_IOSCHED +#define elv_log_ioq(efqd, ioq, fmt, args...) \ +{ \ + blk_add_trace_msg((efqd)->queue, "elv%d%c %s " fmt, (ioq)->pid, \ + elv_ioq_sync(ioq) ? 'S' : 'A', \ + ioq_to_io_group(ioq)->path, ##args); \ +} +#else #define elv_log_ioq(efqd, ioq, fmt, args...) \ blk_add_trace_msg((efqd)->queue, "elv%d%c " fmt, (ioq)->pid, \ elv_ioq_sync(ioq) ? 'S' : 'A', ##args) +#endif #define elv_log(efqd, fmt, args...) \ blk_add_trace_msg((efqd)->queue, "elv " fmt, ##args) -- 1.6.0.6 -- 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/