| Message ID | 20240808071522.14283-2-kinga.stefaniuk@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | md: generate CHANGE uevents for md device | expand |
Hi, sorry for the late reply, just one nit below. 在 2024/08/08 15:15, Kinga Stefaniuk 写道: > In mdadm commit 49b69533e8 ("mdmonitor: check if udev has finished > events processing") mdmonitor has been learnt to wait for udev to finish > processing, and later in commit 9935cf0f64f3 ("Mdmonitor: Improve udev > event handling") pooling for MD events on /proc/mdstat file has been > deprecated because relying on udev events is more reliable and less bug > prone (we are not competing with udev). > > After those changes we are still observing missing mdmonitor events in > some scenarios, especially SpareEvent is likely to be missed. With this > patch MD will be able to generate more change uevents and wakeup > mdmonitor more frequently to give it possibility to notice events. > MD has md_new_events() functionality to trigger events and with this > patch this function is extended to generate udev CHANGE uevents. It > cannot be done directly because this function is called on interrupts > context, so appropriate workqueue is created. Uevents are less time > critical, it is safe to use workqueue. It is limited to CHANGE event as > there is no need to generate other uevents for now. > With this change, mdmonitor events are less likely to be missed. Our > internal tests suite confirms that, mdmonitor reliability is (again) > improved. > > Signed-off-by: Mateusz Grzonka <mateusz.grzonka@intel.com> > Signed-off-by: Kinga Stefaniuk <kinga.stefaniuk@intel.com> > > --- > v9: add using md_wq and fix if (sync) condition > v8: fix possible conflict with del_work by adding spin_lock, > change default sync value to true, now false only on md_error > v7: add new work struct for these events, use md_misc_wq workqueue, > fix work cancellation > v6: use another workqueue and only on md_error, make configurable > if kobject_uevent is run immediately on event or queued > v5: fix flush_work missing and commit message fixes > v4: add more detailed commit message > v3: fix problems with calling function from interrupt context, > add work_queue and queue events notification > v2: resolve merge conflicts with applying the patch > > Signed-off-by: Kinga Stefaniuk <kinga.stefaniuk@intel.com> > --- > drivers/md/md.c | 72 +++++++++++++++++++++++++++++++-------------- > drivers/md/md.h | 3 +- > drivers/md/raid10.c | 2 +- > drivers/md/raid5.c | 2 +- > 4 files changed, 54 insertions(+), 25 deletions(-) > > diff --git a/drivers/md/md.c b/drivers/md/md.c > index 64693913ed18..5afefa4fbf6d 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -107,6 +107,7 @@ static int remove_and_add_spares(struct mddev *mddev, > static void mddev_detach(struct mddev *mddev); > static void export_rdev(struct md_rdev *rdev, struct mddev *mddev); > static void md_wakeup_thread_directly(struct md_thread __rcu *thread); > +static inline struct mddev *mddev_get(struct mddev *mddev); > > /* > * Default number of read corrections we'll attempt on an rdev > @@ -323,6 +324,30 @@ static int start_readonly; > */ > static bool create_on_open = true; > > +/* > + * Enables to iterate over all existing md arrays > + * all_mddevs_lock protects this list. > + */ > +static LIST_HEAD(all_mddevs); > +static DEFINE_SPINLOCK(all_mddevs_lock); > + > +/* > + * Send every new event to the userspace. > + */ > +static void md_kobject_uevent_fn(struct work_struct *work) > +{ > + struct mddev *mddev = container_of(work, struct mddev, uevent_work); > + > + spin_lock(&all_mddevs_lock); > + mddev = mddev_get(mddev); > + spin_unlock(&all_mddevs_lock); > + if (!mddev) > + return; Can you move this mddev_get() before the queue_work()? This is more reasonable. > + > + kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE); > + mddev_put(mddev); > +} > + > /* > * We have a system wide 'event count' that is incremented > * on any 'interesting' event, and readers of /proc/mdstat > @@ -335,20 +360,21 @@ static bool create_on_open = true; > */ > static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters); > static atomic_t md_event_count; > -void md_new_event(void) > + > +void md_new_event(struct mddev *mddev, bool sync) > { > atomic_inc(&md_event_count); > wake_up(&md_event_waiters); > + > + if (mddev_is_dm(mddev)) > + return; > + if (sync) > + kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE); > + else > + queue_work(md_wq, &mddev->uevent_work); > } > EXPORT_SYMBOL_GPL(md_new_event); > > -/* > - * Enables to iterate over all existing md arrays > - * all_mddevs_lock protects this list. > - */ > -static LIST_HEAD(all_mddevs); > -static DEFINE_SPINLOCK(all_mddevs_lock); > - > static bool is_md_suspended(struct mddev *mddev) > { > return percpu_ref_is_dying(&mddev->active_io); > @@ -773,6 +799,7 @@ int mddev_init(struct mddev *mddev) > mddev->resync_max = MaxSector; > mddev->level = LEVEL_NONE; > > + INIT_WORK(&mddev->uevent_work, md_kobject_uevent_fn); > INIT_WORK(&mddev->sync_work, md_start_sync); > INIT_WORK(&mddev->del_work, mddev_delayed_delete); > > @@ -2898,7 +2925,7 @@ static int add_bound_rdev(struct md_rdev *rdev) > if (mddev->degraded) > set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); > set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); > - md_new_event(); > + md_new_event(mddev, true); > return 0; > } > > @@ -3015,7 +3042,7 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len) > md_kick_rdev_from_array(rdev); > if (mddev->pers) > set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags); > - md_new_event(); > + md_new_event(mddev, true); > } > } > } else if (cmd_match(buf, "writemostly")) { > @@ -4131,7 +4158,7 @@ level_store(struct mddev *mddev, const char *buf, size_t len) > if (!mddev->thread) > md_update_sb(mddev, 1); > sysfs_notify_dirent_safe(mddev->sysfs_level); > - md_new_event(); > + md_new_event(mddev, true); > rv = len; > out_unlock: > mddev_unlock_and_resume(mddev); > @@ -4658,7 +4685,7 @@ new_dev_store(struct mddev *mddev, const char *buf, size_t len) > export_rdev(rdev, mddev); > mddev_unlock_and_resume(mddev); > if (!err) > - md_new_event(); > + md_new_event(mddev, true); > return err ? err : len; > } > > @@ -6276,7 +6303,7 @@ int md_run(struct mddev *mddev) > if (mddev->sb_flags) > md_update_sb(mddev, 0); > > - md_new_event(); > + md_new_event(mddev, true); > return 0; > > bitmap_abort: > @@ -6635,7 +6662,7 @@ static int do_md_stop(struct mddev *mddev, int mode) > if (mddev->hold_active == UNTIL_STOP) > mddev->hold_active = 0; > } > - md_new_event(); > + md_new_event(mddev, true); > sysfs_notify_dirent_safe(mddev->sysfs_state); > return 0; > } > @@ -7131,7 +7158,7 @@ static int hot_remove_disk(struct mddev *mddev, dev_t dev) > set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags); > if (!mddev->thread) > md_update_sb(mddev, 1); > - md_new_event(); > + md_new_event(mddev, true); > > return 0; > busy: > @@ -7202,7 +7229,7 @@ static int hot_add_disk(struct mddev *mddev, dev_t dev) > * array immediately. > */ > set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); > - md_new_event(); > + md_new_event(mddev, true); > return 0; > > abort_export: > @@ -8176,7 +8203,8 @@ void md_error(struct mddev *mddev, struct md_rdev *rdev) > } > if (mddev->event_work.func) > queue_work(md_misc_wq, &mddev->event_work); > - md_new_event(); > + if (!test_bit(MD_DELETED, &mddev->flags)) > + md_new_event(mddev, false); And mddev_get() will check MD_DELETED, no need to do this after moving mddev_get() into md_new_event. Otherwise, this patch LGTM. Thanks, Kuai > } > EXPORT_SYMBOL(md_error); > > @@ -9072,7 +9100,7 @@ void md_do_sync(struct md_thread *thread) > mddev->curr_resync = MD_RESYNC_ACTIVE; /* no longer delayed */ > mddev->curr_resync_completed = j; > sysfs_notify_dirent_safe(mddev->sysfs_completed); > - md_new_event(); > + md_new_event(mddev, true); > update_time = jiffies; > > blk_start_plug(&plug); > @@ -9144,7 +9172,7 @@ void md_do_sync(struct md_thread *thread) > /* this is the earliest that rebuild will be > * visible in /proc/mdstat > */ > - md_new_event(); > + md_new_event(mddev, true); > > if (last_check + window > io_sectors || j == max_sectors) > continue; > @@ -9410,7 +9438,7 @@ static int remove_and_add_spares(struct mddev *mddev, > sysfs_link_rdev(mddev, rdev); > if (!test_bit(Journal, &rdev->flags)) > spares++; > - md_new_event(); > + md_new_event(mddev, true); > set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags); > } > } > @@ -9529,7 +9557,7 @@ static void md_start_sync(struct work_struct *ws) > __mddev_resume(mddev, false); > md_wakeup_thread(mddev->sync_thread); > sysfs_notify_dirent_safe(mddev->sysfs_action); > - md_new_event(); > + md_new_event(mddev, true); > return; > > not_running: > @@ -9781,7 +9809,7 @@ void md_reap_sync_thread(struct mddev *mddev) > set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); > sysfs_notify_dirent_safe(mddev->sysfs_completed); > sysfs_notify_dirent_safe(mddev->sysfs_action); > - md_new_event(); > + md_new_event(mddev, true); > if (mddev->event_work.func) > queue_work(md_misc_wq, &mddev->event_work); > wake_up(&resync_wait); > diff --git a/drivers/md/md.h b/drivers/md/md.h > index a0d6827dced9..ab340618828c 100644 > --- a/drivers/md/md.h > +++ b/drivers/md/md.h > @@ -582,6 +582,7 @@ struct mddev { > */ > struct work_struct flush_work; > struct work_struct event_work; /* used by dm to report failure event */ > + struct work_struct uevent_work; > mempool_t *serial_info_pool; > void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev); > struct md_cluster_info *cluster_info; > @@ -883,7 +884,7 @@ extern int md_super_wait(struct mddev *mddev); > extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, > struct page *page, blk_opf_t opf, bool metadata_op); > extern void md_do_sync(struct md_thread *thread); > -extern void md_new_event(void); > +extern void md_new_event(struct mddev *mddev, bool sync); > extern void md_allow_write(struct mddev *mddev); > extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev); > extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); > diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c > index 2a9c4ee982e0..f76571079845 100644 > --- a/drivers/md/raid10.c > +++ b/drivers/md/raid10.c > @@ -4542,7 +4542,7 @@ static int raid10_start_reshape(struct mddev *mddev) > set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); > set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); > conf->reshape_checkpoint = jiffies; > - md_new_event(); > + md_new_event(mddev, true); > return 0; > > abort: > diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c > index c14cf2410365..9da091b000d7 100644 > --- a/drivers/md/raid5.c > +++ b/drivers/md/raid5.c > @@ -8525,7 +8525,7 @@ static int raid5_start_reshape(struct mddev *mddev) > set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); > set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); > conf->reshape_checkpoint = jiffies; > - md_new_event(); > + md_new_event(mddev, true); > return 0; > } > >
diff --git a/drivers/md/md.c b/drivers/md/md.c index 64693913ed18..5afefa4fbf6d 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -107,6 +107,7 @@ static int remove_and_add_spares(struct mddev *mddev, static void mddev_detach(struct mddev *mddev); static void export_rdev(struct md_rdev *rdev, struct mddev *mddev); static void md_wakeup_thread_directly(struct md_thread __rcu *thread); +static inline struct mddev *mddev_get(struct mddev *mddev); /* * Default number of read corrections we'll attempt on an rdev @@ -323,6 +324,30 @@ static int start_readonly; */ static bool create_on_open = true; +/* + * Enables to iterate over all existing md arrays + * all_mddevs_lock protects this list. + */ +static LIST_HEAD(all_mddevs); +static DEFINE_SPINLOCK(all_mddevs_lock); + +/* + * Send every new event to the userspace. + */ +static void md_kobject_uevent_fn(struct work_struct *work) +{ + struct mddev *mddev = container_of(work, struct mddev, uevent_work); + + spin_lock(&all_mddevs_lock); + mddev = mddev_get(mddev); + spin_unlock(&all_mddevs_lock); + if (!mddev) + return; + + kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE); + mddev_put(mddev); +} + /* * We have a system wide 'event count' that is incremented * on any 'interesting' event, and readers of /proc/mdstat @@ -335,20 +360,21 @@ static bool create_on_open = true; */ static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters); static atomic_t md_event_count; -void md_new_event(void) + +void md_new_event(struct mddev *mddev, bool sync) { atomic_inc(&md_event_count); wake_up(&md_event_waiters); + + if (mddev_is_dm(mddev)) + return; + if (sync) + kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE); + else + queue_work(md_wq, &mddev->uevent_work); } EXPORT_SYMBOL_GPL(md_new_event); -/* - * Enables to iterate over all existing md arrays - * all_mddevs_lock protects this list. - */ -static LIST_HEAD(all_mddevs); -static DEFINE_SPINLOCK(all_mddevs_lock); - static bool is_md_suspended(struct mddev *mddev) { return percpu_ref_is_dying(&mddev->active_io); @@ -773,6 +799,7 @@ int mddev_init(struct mddev *mddev) mddev->resync_max = MaxSector; mddev->level = LEVEL_NONE; + INIT_WORK(&mddev->uevent_work, md_kobject_uevent_fn); INIT_WORK(&mddev->sync_work, md_start_sync); INIT_WORK(&mddev->del_work, mddev_delayed_delete); @@ -2898,7 +2925,7 @@ static int add_bound_rdev(struct md_rdev *rdev) if (mddev->degraded) set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); - md_new_event(); + md_new_event(mddev, true); return 0; } @@ -3015,7 +3042,7 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len) md_kick_rdev_from_array(rdev); if (mddev->pers) set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags); - md_new_event(); + md_new_event(mddev, true); } } } else if (cmd_match(buf, "writemostly")) { @@ -4131,7 +4158,7 @@ level_store(struct mddev *mddev, const char *buf, size_t len) if (!mddev->thread) md_update_sb(mddev, 1); sysfs_notify_dirent_safe(mddev->sysfs_level); - md_new_event(); + md_new_event(mddev, true); rv = len; out_unlock: mddev_unlock_and_resume(mddev); @@ -4658,7 +4685,7 @@ new_dev_store(struct mddev *mddev, const char *buf, size_t len) export_rdev(rdev, mddev); mddev_unlock_and_resume(mddev); if (!err) - md_new_event(); + md_new_event(mddev, true); return err ? err : len; } @@ -6276,7 +6303,7 @@ int md_run(struct mddev *mddev) if (mddev->sb_flags) md_update_sb(mddev, 0); - md_new_event(); + md_new_event(mddev, true); return 0; bitmap_abort: @@ -6635,7 +6662,7 @@ static int do_md_stop(struct mddev *mddev, int mode) if (mddev->hold_active == UNTIL_STOP) mddev->hold_active = 0; } - md_new_event(); + md_new_event(mddev, true); sysfs_notify_dirent_safe(mddev->sysfs_state); return 0; } @@ -7131,7 +7158,7 @@ static int hot_remove_disk(struct mddev *mddev, dev_t dev) set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags); if (!mddev->thread) md_update_sb(mddev, 1); - md_new_event(); + md_new_event(mddev, true); return 0; busy: @@ -7202,7 +7229,7 @@ static int hot_add_disk(struct mddev *mddev, dev_t dev) * array immediately. */ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); - md_new_event(); + md_new_event(mddev, true); return 0; abort_export: @@ -8176,7 +8203,8 @@ void md_error(struct mddev *mddev, struct md_rdev *rdev) } if (mddev->event_work.func) queue_work(md_misc_wq, &mddev->event_work); - md_new_event(); + if (!test_bit(MD_DELETED, &mddev->flags)) + md_new_event(mddev, false); } EXPORT_SYMBOL(md_error); @@ -9072,7 +9100,7 @@ void md_do_sync(struct md_thread *thread) mddev->curr_resync = MD_RESYNC_ACTIVE; /* no longer delayed */ mddev->curr_resync_completed = j; sysfs_notify_dirent_safe(mddev->sysfs_completed); - md_new_event(); + md_new_event(mddev, true); update_time = jiffies; blk_start_plug(&plug); @@ -9144,7 +9172,7 @@ void md_do_sync(struct md_thread *thread) /* this is the earliest that rebuild will be * visible in /proc/mdstat */ - md_new_event(); + md_new_event(mddev, true); if (last_check + window > io_sectors || j == max_sectors) continue; @@ -9410,7 +9438,7 @@ static int remove_and_add_spares(struct mddev *mddev, sysfs_link_rdev(mddev, rdev); if (!test_bit(Journal, &rdev->flags)) spares++; - md_new_event(); + md_new_event(mddev, true); set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags); } } @@ -9529,7 +9557,7 @@ static void md_start_sync(struct work_struct *ws) __mddev_resume(mddev, false); md_wakeup_thread(mddev->sync_thread); sysfs_notify_dirent_safe(mddev->sysfs_action); - md_new_event(); + md_new_event(mddev, true); return; not_running: @@ -9781,7 +9809,7 @@ void md_reap_sync_thread(struct mddev *mddev) set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); sysfs_notify_dirent_safe(mddev->sysfs_completed); sysfs_notify_dirent_safe(mddev->sysfs_action); - md_new_event(); + md_new_event(mddev, true); if (mddev->event_work.func) queue_work(md_misc_wq, &mddev->event_work); wake_up(&resync_wait); diff --git a/drivers/md/md.h b/drivers/md/md.h index a0d6827dced9..ab340618828c 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -582,6 +582,7 @@ struct mddev { */ struct work_struct flush_work; struct work_struct event_work; /* used by dm to report failure event */ + struct work_struct uevent_work; mempool_t *serial_info_pool; void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev); struct md_cluster_info *cluster_info; @@ -883,7 +884,7 @@ extern int md_super_wait(struct mddev *mddev); extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, struct page *page, blk_opf_t opf, bool metadata_op); extern void md_do_sync(struct md_thread *thread); -extern void md_new_event(void); +extern void md_new_event(struct mddev *mddev, bool sync); extern void md_allow_write(struct mddev *mddev); extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev); extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 2a9c4ee982e0..f76571079845 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -4542,7 +4542,7 @@ static int raid10_start_reshape(struct mddev *mddev) set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); conf->reshape_checkpoint = jiffies; - md_new_event(); + md_new_event(mddev, true); return 0; abort: diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index c14cf2410365..9da091b000d7 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -8525,7 +8525,7 @@ static int raid5_start_reshape(struct mddev *mddev) set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); conf->reshape_checkpoint = jiffies; - md_new_event(); + md_new_event(mddev, true); return 0; }
In mdadm commit 49b69533e8 ("mdmonitor: check if udev has finished events processing") mdmonitor has been learnt to wait for udev to finish processing, and later in commit 9935cf0f64f3 ("Mdmonitor: Improve udev event handling") pooling for MD events on /proc/mdstat file has been deprecated because relying on udev events is more reliable and less bug prone (we are not competing with udev). After those changes we are still observing missing mdmonitor events in some scenarios, especially SpareEvent is likely to be missed. With this patch MD will be able to generate more change uevents and wakeup mdmonitor more frequently to give it possibility to notice events. MD has md_new_events() functionality to trigger events and with this patch this function is extended to generate udev CHANGE uevents. It cannot be done directly because this function is called on interrupts context, so appropriate workqueue is created. Uevents are less time critical, it is safe to use workqueue. It is limited to CHANGE event as there is no need to generate other uevents for now. With this change, mdmonitor events are less likely to be missed. Our internal tests suite confirms that, mdmonitor reliability is (again) improved. Signed-off-by: Mateusz Grzonka <mateusz.grzonka@intel.com> Signed-off-by: Kinga Stefaniuk <kinga.stefaniuk@intel.com> --- v9: add using md_wq and fix if (sync) condition v8: fix possible conflict with del_work by adding spin_lock, change default sync value to true, now false only on md_error v7: add new work struct for these events, use md_misc_wq workqueue, fix work cancellation v6: use another workqueue and only on md_error, make configurable if kobject_uevent is run immediately on event or queued v5: fix flush_work missing and commit message fixes v4: add more detailed commit message v3: fix problems with calling function from interrupt context, add work_queue and queue events notification v2: resolve merge conflicts with applying the patch Signed-off-by: Kinga Stefaniuk <kinga.stefaniuk@intel.com> --- drivers/md/md.c | 72 +++++++++++++++++++++++++++++++-------------- drivers/md/md.h | 3 +- drivers/md/raid10.c | 2 +- drivers/md/raid5.c | 2 +- 4 files changed, 54 insertions(+), 25 deletions(-)