From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755789Ab0DCB74 (ORCPT ); Fri, 2 Apr 2010 21:59:56 -0400 Received: from smtp-out.google.com ([74.125.121.35]:15602 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755609Ab0DCB7v convert rfc822-to-8bit (ORCPT ); Fri, 2 Apr 2010 21:59:51 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=mime-version:in-reply-to:references:from:date:message-id: subject:to:cc:content-type:content-transfer-encoding:x-system-of-record; b=hgRqySuY9J40fjT5DNMamdhPTinqPbLY901oxvnrbvg4E8KMD7F/D2z+KC3gLRzyR 32yNTxoLty+FqNK3y6x5w== MIME-Version: 1.0 In-Reply-To: <20100403015553.30746.86746.stgit@austin.mtv.corp.google.com> References: <20100403014724.30746.16081.stgit@austin.mtv.corp.google.com> <20100403015553.30746.86746.stgit@austin.mtv.corp.google.com> From: Divyesh Shah Date: Fri, 2 Apr 2010 18:59:18 -0700 Message-ID: Subject: Re: [PATCH 2/3][v2] blkio: Add io controller stats like To: jens.axboe@oracle.com, vgoyal@redhat.com Cc: linux-kernel@vger.kernel.org, nauman@google.com, ctalbott@google.com Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Missed the v2 tag on this patch. Resending. Apologies for the spam. On Fri, Apr 2, 2010 at 6:56 PM, Divyesh Shah wrote: > - io_service_time (the actual time in ns taken by the dis to service the IO) > - io_wait_time (the time spent waiting in the IO shceduler queues before >  getting serviced) > - io_serviced (number of IOs serviced from this blkio_group) > - io_service_bytes (Number of bytes served for this cgroup) > > These stats are accumulated per operation type helping us to distinguish between > read and write, and sync and async IO. This patch does not increment any of > these stats. > > Signed-off-by: Divyesh Shah > --- > >  Documentation/cgroups/blkio-controller.txt |   33 +++++ >  block/blk-cgroup.c                         |  179 +++++++++++++++++++++++++--- >  block/blk-cgroup.h                         |   41 +++++- >  block/cfq-iosched.c                        |    2 >  4 files changed, 229 insertions(+), 26 deletions(-) > > diff --git a/Documentation/cgroups/blkio-controller.txt b/Documentation/cgroups/blkio-controller.txt > index 630879c..ededdca 100644 > --- a/Documentation/cgroups/blkio-controller.txt > +++ b/Documentation/cgroups/blkio-controller.txt > @@ -75,6 +75,9 @@ CONFIG_DEBUG_BLK_CGROUP > >  Details of cgroup files >  ======================= > +Writing an int to any of the stats files (which excludes weight) will result > +in all stats for that cgroup to be erased. > + >  - blkio.weight >        - Specifies per cgroup weight. > > @@ -92,6 +95,36 @@ Details of cgroup files >          third field specifies the number of sectors transferred by the >          group to/from the device. > > +- blkio.io_service_bytes > +       - Number of bytes transferred to/from the disk by the group. These > +         are further divided by the type of operation - read or write, sync > +         or async. First two fields specify the major and minor number of the > +         device, third field specifies the operation type and the fourth field > +         specifies the number of bytes. > + > +- blkio.io_serviced > +       - Number of IOs completed to/from the disk by the group. These > +         are further divided by the type of operation - read or write, sync > +         or async. First two fields specify the major and minor number of the > +         device, third field specifies the operation type and the fourth field > +         specifies the number of IOs. > + > +- blkio.io_service_time > +       - Total amount of time spent by the device to service the IOs for this > +         cgroup. This is in nanoseconds to make it meaningful for flash > +         devices too. This time is further divided by the type of operation - > +         read or write, sync or async. First two fields specify the major and > +         minor number of the device, third field specifies the operation type > +         and the fourth field specifies the io_service_time in ns. > + > +- blkio.io_wait_time > +       - Total amount of time the IO spent waiting in the scheduler queues for > +         service. This is in nanoseconds to make it meaningful for flash > +         devices too. This time is further divided by the type of operation - > +         read or write, sync or async. First two fields specify the major and > +         minor number of the device, third field specifies the operation type > +         and the fourth field specifies the io_wait_time in ns. > + >  - blkio.dequeue >        - Debugging aid only enabled if CONFIG_DEBUG_CFQ_IOSCHED=y. This >          gives the statistics about how many a times a group was dequeued > diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c > index 5be3981..cac10b2 100644 > --- a/block/blk-cgroup.c > +++ b/block/blk-cgroup.c > @@ -17,6 +17,8 @@ >  #include >  #include "blk-cgroup.h" > > +#define MAX_KEY_LEN 100 > + >  static DEFINE_SPINLOCK(blkio_list_lock); >  static LIST_HEAD(blkio_list); > > @@ -55,12 +57,15 @@ struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup) >  } >  EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup); > > -void blkiocg_update_blkio_group_stats(struct blkio_group *blkg, > -                                               unsigned long time) > +void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time) >  { > -       blkg->time += time; > +       unsigned long flags; > + > +       spin_lock_irqsave(&blkg->stats_lock, flags); > +       blkg->stats.time += time; > +       spin_unlock_irqrestore(&blkg->stats_lock, flags); >  } > -EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_stats); > +EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used); > >  void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, >                        struct blkio_group *blkg, void *key, dev_t dev) > @@ -170,13 +175,119 @@ blkiocg_weight_write(struct cgroup *cgroup, struct cftype *cftype, u64 val) >        return 0; >  } > > -#define SHOW_FUNCTION_PER_GROUP(__VAR)                                 \ > +static int > +blkiocg_reset_write(struct cgroup *cgroup, struct cftype *cftype, u64 val) > +{ > +       struct blkio_cgroup *blkcg; > +       struct blkio_group *blkg; > +       struct hlist_node *n; > +       struct blkio_group_stats *stats; > + > +       blkcg = cgroup_to_blkio_cgroup(cgroup); > +       spin_lock_irq(&blkcg->lock); > +       hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { > +               spin_lock(&blkg->stats_lock); > +               stats = &blkg->stats; > +               memset(stats, 0, sizeof(struct blkio_group_stats)); > +               spin_unlock(&blkg->stats_lock); > +       } > +       spin_unlock_irq(&blkcg->lock); > +       return 0; > +} > + > +static void blkio_get_key_name(int type, dev_t dev, char *str, int chars_left) > +{ > +       snprintf(str, chars_left, "%u:%u", MAJOR(dev), MINOR(dev)); > +       chars_left -= strlen(str); > +       if (chars_left <= 0) { > +               printk(KERN_WARNING > +                       "Possibly incorrect cgroup stat display format"); > +               return; > +       } > +       switch (type) { > +       case IO_READ: > +               strlcat(str, " Read", chars_left); > +               break; > +       case IO_WRITE: > +               strlcat(str, " Write", chars_left); > +               break; > +       case IO_SYNC: > +               strlcat(str, " Sync", chars_left); > +               break; > +       case IO_ASYNC: > +               strlcat(str, " Async", chars_left); > +               break; > +       case IO_TYPE_TOTAL: > +               strlcat(str, " Total", chars_left); > +               break; > +       default: > +               strlcat(str, " Invalid", chars_left); > +       } > +} > + > +typedef uint64_t (get_var) (struct blkio_group *, int); > + > +static uint64_t blkio_get_typed_stat(struct blkio_group *blkg, > +               struct cgroup_map_cb *cb, get_var *getvar, dev_t dev) > +{ > +       uint64_t disk_total; > +       char key_str[MAX_KEY_LEN]; > +       int type; > + > +       for (type = 0; type < IO_TYPE_TOTAL; type++) { > +               blkio_get_key_name(type, dev, key_str, MAX_KEY_LEN); > +               cb->fill(cb, key_str, getvar(blkg, type)); > +       } > +       disk_total = getvar(blkg, IO_READ) + getvar(blkg, IO_WRITE); > +       blkio_get_key_name(IO_TYPE_TOTAL, dev, key_str, MAX_KEY_LEN); > +       cb->fill(cb, key_str, disk_total); > +       return disk_total; > +} > + > +static uint64_t blkio_get_stat(struct blkio_group *blkg, > +               struct cgroup_map_cb *cb, get_var *getvar, dev_t dev) > +{ > +       uint64_t var = getvar(blkg, 0); > +       char str[10]; > + > +       snprintf(str, 10, "%u:%u", MAJOR(dev), MINOR(dev)); > +       cb->fill(cb, str, var); > +       return var; > +} > + > +#define GET_STAT_INDEXED(__VAR)                                                \ > +uint64_t blkio_get_##__VAR##_stat(struct blkio_group *blkg, int type)  \ > +{                                                                      \ > +       return blkg->stats.__VAR[type];                                 \ > +}                                                                      \ > + > +GET_STAT_INDEXED(io_service_bytes); > +GET_STAT_INDEXED(io_serviced); > +GET_STAT_INDEXED(io_service_time); > +GET_STAT_INDEXED(io_wait_time); > +#undef GET_STAT_INDEXED > + > +#define GET_STAT(__VAR)                                                        \ > +uint64_t blkio_get_##__VAR##_stat(struct blkio_group *blkg, int dummy) \ > +{                                                                      \ > +       return blkg->stats.__VAR;                                       \ > +} > + > +GET_STAT(time); > +GET_STAT(sectors); > +#ifdef CONFIG_DEBUG_BLK_CGROUP > +GET_STAT(dequeue); > +#endif > +#undef GET_STAT > + > +#define SHOW_FUNCTION_PER_GROUP(__VAR, get_stats, getvar, show_total)  \ >  static int blkiocg_##__VAR##_read(struct cgroup *cgroup,               \ > -                       struct cftype *cftype, struct seq_file *m)      \ > +               struct cftype *cftype, struct cgroup_map_cb *cb)        \ >  {                                                                      \ >        struct blkio_cgroup *blkcg;                                     \ >        struct blkio_group *blkg;                                       \ >        struct hlist_node *n;                                           \ > +       uint64_t cgroup_total = 0;                                      \ >                                                                        \ >        if (!cgroup_lock_live_group(cgroup))                            \ >                return -ENODEV;                                         \ > @@ -184,19 +295,32 @@ static int blkiocg_##__VAR##_read(struct cgroup *cgroup,          \ >        blkcg = cgroup_to_blkio_cgroup(cgroup);                         \ >        rcu_read_lock();                                                \ >        hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {\ > -               if (blkg->dev)                                          \ > -                       seq_printf(m, "%u:%u %lu\n", MAJOR(blkg->dev),  \ > -                                MINOR(blkg->dev), blkg->__VAR);        \ > +               if (blkg->dev) {                                        \ > +                       spin_lock_irq(&blkg->stats_lock);               \ > +                       cgroup_total += get_stats(blkg, cb, getvar,     \ > +                                               blkg->dev);             \ > +                       spin_unlock_irq(&blkg->stats_lock);             \ > +               }                                                       \ >        }                                                               \ > +       if (show_total)                                                 \ > +               cb->fill(cb, "Total", cgroup_total);                    \ >        rcu_read_unlock();                                              \ >        cgroup_unlock();                                                \ >        return 0;                                                       \ >  } > > -SHOW_FUNCTION_PER_GROUP(time); > -SHOW_FUNCTION_PER_GROUP(sectors); > +SHOW_FUNCTION_PER_GROUP(time, blkio_get_stat, blkio_get_time_stat, 0); > +SHOW_FUNCTION_PER_GROUP(sectors, blkio_get_stat, blkio_get_sectors_stat, 0); > +SHOW_FUNCTION_PER_GROUP(io_service_bytes, blkio_get_typed_stat, > +                       blkio_get_io_service_bytes_stat, 1); > +SHOW_FUNCTION_PER_GROUP(io_serviced, blkio_get_typed_stat, > +                       blkio_get_io_serviced_stat, 1); > +SHOW_FUNCTION_PER_GROUP(io_service_time, blkio_get_typed_stat, > +                       blkio_get_io_service_time_stat, 1); > +SHOW_FUNCTION_PER_GROUP(io_wait_time, blkio_get_typed_stat, > +                       blkio_get_io_wait_time_stat, 1); >  #ifdef CONFIG_DEBUG_BLK_CGROUP > -SHOW_FUNCTION_PER_GROUP(dequeue); > +SHOW_FUNCTION_PER_GROUP(dequeue, blkio_get_stat, blkio_get_dequeue_stat, 0); >  #endif >  #undef SHOW_FUNCTION_PER_GROUP > > @@ -204,7 +328,7 @@ SHOW_FUNCTION_PER_GROUP(dequeue); >  void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg, >                        unsigned long dequeue) >  { > -       blkg->dequeue += dequeue; > +       blkg->stats.dequeue += dequeue; >  } >  EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_dequeue_stats); >  #endif > @@ -217,16 +341,39 @@ struct cftype blkio_files[] = { >        }, >        { >                .name = "time", > -               .read_seq_string = blkiocg_time_read, > +               .read_map = blkiocg_time_read, > +               .write_u64 = blkiocg_reset_write, >        }, >        { >                .name = "sectors", > -               .read_seq_string = blkiocg_sectors_read, > +               .read_map = blkiocg_sectors_read, > +               .write_u64 = blkiocg_reset_write, > +       }, > +       { > +               .name = "io_service_bytes", > +               .read_map = blkiocg_io_service_bytes_read, > +               .write_u64 = blkiocg_reset_write, > +       }, > +       { > +               .name = "io_serviced", > +               .read_map = blkiocg_io_serviced_read, > +               .write_u64 = blkiocg_reset_write, > +       }, > +       { > +               .name = "io_service_time", > +               .read_map = blkiocg_io_service_time_read, > +               .write_u64 = blkiocg_reset_write, > +       }, > +       { > +               .name = "io_wait_time", > +               .read_map = blkiocg_io_wait_time_read, > +               .write_u64 = blkiocg_reset_write, >        }, >  #ifdef CONFIG_DEBUG_BLK_CGROUP >        { >                .name = "dequeue", > -               .read_seq_string = blkiocg_dequeue_read, > +               .read_map = blkiocg_dequeue_read, > +               .write_u64 = blkiocg_reset_write, >        }, >  #endif >  }; > diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h > index fe44517..e8600b0 100644 > --- a/block/blk-cgroup.h > +++ b/block/blk-cgroup.h > @@ -23,6 +23,14 @@ extern struct cgroup_subsys blkio_subsys; >  #define blkio_subsys_id blkio_subsys.subsys_id >  #endif > > +enum io_type { > +       IO_READ = 0, > +       IO_WRITE, > +       IO_SYNC, > +       IO_ASYNC, > +       IO_TYPE_TOTAL > +}; > + >  struct blkio_cgroup { >        struct cgroup_subsys_state css; >        unsigned int weight; > @@ -30,6 +38,23 @@ struct blkio_cgroup { >        struct hlist_head blkg_list; >  }; > > +struct blkio_group_stats { > +       /* total disk time and nr sectors dispatched by this group */ > +       uint64_t time; > +       uint64_t sectors; > +       /* Total disk time used by IOs in ns */ > +       uint64_t io_service_time[IO_TYPE_TOTAL]; > +       uint64_t io_service_bytes[IO_TYPE_TOTAL]; /* Total bytes transferred */ > +       /* Total IOs serviced, post merge */ > +       uint64_t io_serviced[IO_TYPE_TOTAL]; > +       /* Total time spent waiting in scheduler queue in ns */ > +       uint64_t io_wait_time[IO_TYPE_TOTAL]; > +#ifdef CONFIG_DEBUG_BLK_CGROUP > +       /* How many times this group has been removed from service tree */ > +       unsigned long dequeue; > +#endif > +}; > + >  struct blkio_group { >        /* An rcu protected unique identifier for the group */ >        void *key; > @@ -38,15 +63,13 @@ struct blkio_group { >  #ifdef CONFIG_DEBUG_BLK_CGROUP >        /* Store cgroup path */ >        char path[128]; > -       /* How many times this group has been removed from service tree */ > -       unsigned long dequeue; >  #endif >        /* The device MKDEV(major, minor), this group has been created for */ > -       dev_t   dev; > +       dev_t dev; > > -       /* total disk time and nr sectors dispatched by this group */ > -       unsigned long time; > -       unsigned long sectors; > +       /* Need to serialize the stats in the case of reset/update */ > +       spinlock_t stats_lock; > +       struct blkio_group_stats stats; >  }; > >  typedef void (blkio_unlink_group_fn) (void *key, struct blkio_group *blkg); > @@ -105,8 +128,8 @@ extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, >  extern int blkiocg_del_blkio_group(struct blkio_group *blkg); >  extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg, >                                                void *key); > -void blkiocg_update_blkio_group_stats(struct blkio_group *blkg, > -                                               unsigned long time); > +void blkiocg_update_timeslice_used(struct blkio_group *blkg, > +                                       unsigned long time); >  #else >  struct cgroup; >  static inline struct blkio_cgroup * > @@ -122,7 +145,7 @@ blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; } > >  static inline struct blkio_group * >  blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; } > -static inline void blkiocg_update_blkio_group_stats(struct blkio_group *blkg, > +static inline void blkiocg_update_timeslice_used(struct blkio_group *blkg, >                                                unsigned long time) {} >  #endif >  #endif /* _BLK_CGROUP_H */ > diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c > index c18e348..d91df9f 100644 > --- a/block/cfq-iosched.c > +++ b/block/cfq-iosched.c > @@ -914,7 +914,7 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg, > >        cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime, >                                        st->min_vdisktime); > -       blkiocg_update_blkio_group_stats(&cfqg->blkg, used_sl); > +       blkiocg_update_timeslice_used(&cfqg->blkg, used_sl); >  } > >  #ifdef CONFIG_CFQ_GROUP_IOSCHED > >