On Fri, May 04, 2018 at 09:39:04AM +1000, NeilBrown wrote:
> On Wed, May 02 2018, James Simmons wrote:
>
> >> This data structure only needs to be public so that
> >> various modules can access a wait queue to wait for object
> >> destruction.
> >> If we provide a function to get the wait queue, rather than the
> >> whole bucket, the structure can be made private.
> >>
> >> Signed-off-by: NeilBrown <ne...@suse.com>
> >> ---
> >> drivers/staging/lustre/lustre/include/lu_object.h | 36 +-------------
> >> drivers/staging/lustre/lustre/llite/lcommon_cl.c | 8 ++-
> >> drivers/staging/lustre/lustre/lov/lov_object.c | 8 ++-
> >> drivers/staging/lustre/lustre/obdclass/lu_object.c | 50
> >> +++++++++++++++++---
> >> 4 files changed, 54 insertions(+), 48 deletions(-)
> >>
> >> diff --git a/drivers/staging/lustre/lustre/include/lu_object.h
> >> b/drivers/staging/lustre/lustre/include/lu_object.h
> >> index c3b0ed518819..f29bbca5af65 100644
> >> --- a/drivers/staging/lustre/lustre/include/lu_object.h
> >> +++ b/drivers/staging/lustre/lustre/include/lu_object.h
> >> @@ -549,31 +549,7 @@ struct lu_object_header {
> >> };
> >>
> >> struct fld;
> >> -
> >> -struct lu_site_bkt_data {
> >> - /**
> >> - * number of object in this bucket on the lsb_lru list.
> >> - */
> >> - long lsb_lru_len;
> >> - /**
> >> - * LRU list, updated on each access to object. Protected by
> >> - * bucket lock of lu_site::ls_obj_hash.
> >> - *
> >> - * "Cold" end of LRU is lu_site::ls_lru.next. Accessed object are
> >> - * moved to the lu_site::ls_lru.prev (this is due to the non-existence
> >> - * of list_for_each_entry_safe_reverse()).
> >> - */
> >> - struct list_head lsb_lru;
> >> - /**
> >> - * Wait-queue signaled when an object in this site is ultimately
> >> - * destroyed (lu_object_free()). It is used by lu_object_find() to
> >> - * wait before re-trying when object in the process of destruction is
> >> - * found in the hash table.
> >> - *
> >> - * \see htable_lookup().
> >> - */
> >> - wait_queue_head_t lsb_marche_funebre;
> >> -};
> >> +struct lu_site_bkt_data;
> >>
> >> enum {
> >> LU_SS_CREATED = 0,
> >> @@ -642,14 +618,8 @@ struct lu_site {
> >> struct percpu_counter ls_lru_len_counter;
> >> };
> >>
> >> -static inline struct lu_site_bkt_data *
> >> -lu_site_bkt_from_fid(struct lu_site *site, struct lu_fid *fid)
> >> -{
> >> - struct cfs_hash_bd bd;
> >> -
> >> - cfs_hash_bd_get(site->ls_obj_hash, fid, &bd);
> >> - return cfs_hash_bd_extra_get(site->ls_obj_hash, &bd);
> >> -}
> >> +wait_queue_head_t *
> >> +lu_site_wq_from_fid(struct lu_site *site, struct lu_fid *fid);
> >>
> >> static inline struct seq_server_site *lu_site2seq(const struct lu_site *s)
> >> {
> >> diff --git a/drivers/staging/lustre/lustre/llite/lcommon_cl.c
> >> b/drivers/staging/lustre/lustre/llite/lcommon_cl.c
> >> index df5c0c0ae703..d5b42fb1d601 100644
> >> --- a/drivers/staging/lustre/lustre/llite/lcommon_cl.c
> >> +++ b/drivers/staging/lustre/lustre/llite/lcommon_cl.c
> >> @@ -211,12 +211,12 @@ static void cl_object_put_last(struct lu_env *env,
> >> struct cl_object *obj)
> >>
> >> if (unlikely(atomic_read(&header->loh_ref) != 1)) {
> >> struct lu_site *site = obj->co_lu.lo_dev->ld_site;
> >> - struct lu_site_bkt_data *bkt;
> >> + wait_queue_head_t *wq;
> >>
> >> - bkt = lu_site_bkt_from_fid(site, &header->loh_fid);
> >> + wq = lu_site_wq_from_fid(site, &header->loh_fid);
> >>
> >> init_waitqueue_entry(&waiter, current);
> >> - add_wait_queue(&bkt->lsb_marche_funebre, &waiter);
> >> + add_wait_queue(wq, &waiter);
> >>
> >> while (1) {
> >> set_current_state(TASK_UNINTERRUPTIBLE);
> >> @@ -226,7 +226,7 @@ static void cl_object_put_last(struct lu_env *env,
> >> struct cl_object *obj)
> >> }
> >>
> >> set_current_state(TASK_RUNNING);
> >> - remove_wait_queue(&bkt->lsb_marche_funebre, &waiter);
> >> + remove_wait_queue(wq, &waiter);
> >> }
> >>
> >> cl_object_put(env, obj);
> >> diff --git a/drivers/staging/lustre/lustre/lov/lov_object.c
> >> b/drivers/staging/lustre/lustre/lov/lov_object.c
> >> index f7c69680cb7d..adc90f310fd7 100644
> >> --- a/drivers/staging/lustre/lustre/lov/lov_object.c
> >> +++ b/drivers/staging/lustre/lustre/lov/lov_object.c
> >> @@ -370,7 +370,7 @@ static void lov_subobject_kill(const struct lu_env
> >> *env, struct lov_object *lov,
> >> struct cl_object *sub;
> >> struct lov_layout_raid0 *r0;
> >> struct lu_site *site;
> >> - struct lu_site_bkt_data *bkt;
> >> + wait_queue_head_t *wq;
> >> wait_queue_entry_t *waiter;
> >>
> >> r0 = &lov->u.raid0;
> >> @@ -378,7 +378,7 @@ static void lov_subobject_kill(const struct lu_env
> >> *env, struct lov_object *lov,
> >>
> >> sub = lovsub2cl(los);
> >> site = sub->co_lu.lo_dev->ld_site;
> >> - bkt = lu_site_bkt_from_fid(site, &sub->co_lu.lo_header->loh_fid);
> >> + wq = lu_site_wq_from_fid(site, &sub->co_lu.lo_header->loh_fid);
> >>
> >> cl_object_kill(env, sub);
> >> /* release a reference to the sub-object and ... */
> >> @@ -391,7 +391,7 @@ static void lov_subobject_kill(const struct lu_env
> >> *env, struct lov_object *lov,
> >> if (r0->lo_sub[idx] == los) {
> >> waiter = &lov_env_info(env)->lti_waiter;
> >> init_waitqueue_entry(waiter, current);
> >> - add_wait_queue(&bkt->lsb_marche_funebre, waiter);
> >> + add_wait_queue(wq, waiter);
> >> set_current_state(TASK_UNINTERRUPTIBLE);
> >> while (1) {
> >> /* this wait-queue is signaled at the end of
> >> @@ -408,7 +408,7 @@ static void lov_subobject_kill(const struct lu_env
> >> *env, struct lov_object *lov,
> >> break;
> >> }
> >> }
> >> - remove_wait_queue(&bkt->lsb_marche_funebre, waiter);
> >> + remove_wait_queue(wq, waiter);
> >> }
> >> LASSERT(!r0->lo_sub[idx]);
> >> }
> >> diff --git a/drivers/staging/lustre/lustre/obdclass/lu_object.c
> >> b/drivers/staging/lustre/lustre/obdclass/lu_object.c
> >> index 3de7dc0497c4..2a8a25d6edb5 100644
> >> --- a/drivers/staging/lustre/lustre/obdclass/lu_object.c
> >> +++ b/drivers/staging/lustre/lustre/obdclass/lu_object.c
> >> @@ -56,6 +56,31 @@
> >> #include <lu_ref.h>
> >> #include <linux/list.h>
> >>
> >> +struct lu_site_bkt_data {
> >> + /**
> >> + * number of object in this bucket on the lsb_lru list.
> >> + */
> >> + long lsb_lru_len;
> >> + /**
> >> + * LRU list, updated on each access to object. Protected by
> >> + * bucket lock of lu_site::ls_obj_hash.
> >> + *
> >> + * "Cold" end of LRU is lu_site::ls_lru.next. Accessed object are
> >> + * moved to the lu_site::ls_lru.prev (this is due to the non-existence
> >> + * of list_for_each_entry_safe_reverse()).
> >> + */
> >> + struct list_head lsb_lru;
> >> + /**
> >> + * Wait-queue signaled when an object in this site is ultimately
> >> + * destroyed (lu_object_free()). It is used by lu_object_find() to
> >> + * wait before re-trying when object in the process of destruction is
> >> + * found in the hash table.
> >> + *
> >> + * \see htable_lookup().
> >> + */
> >> + wait_queue_head_t lsb_marche_funebre;
> >> +};
> >> +
> >> enum {
> >> LU_CACHE_PERCENT_MAX = 50,
> >> LU_CACHE_PERCENT_DEFAULT = 20
> >> @@ -88,6 +113,17 @@ MODULE_PARM_DESC(lu_cache_nr, "Maximum number of
> >> objects in lu_object cache");
> >> static void lu_object_free(const struct lu_env *env, struct lu_object *o);
> >> static __u32 ls_stats_read(struct lprocfs_stats *stats, int idx);
> >>
> >> +wait_queue_head_t *
> >> +lu_site_wq_from_fid(struct lu_site *site, struct lu_fid *fid)
> >> +{
> >> + struct cfs_hash_bd bd;
> >> + struct lu_site_bkt_data *bkt;
> >> +
> >> + cfs_hash_bd_get(site->ls_obj_hash, fid, &bd);
> >> + bkt = cfs_hash_bd_extra_get(site->ls_obj_hash, &bd);
> >> + return &bkt->lsb_marche_funebre;
> >> +}
> >> +
> >
> > Nak. You forgot the EXPORT_SYMBOL for this. Once I added the export symbol
> > it seems to work so far in my testing.
>
> Thanks! I'll try to remember the occasional build-test with modules.
'make allmodconfig' is your friend :)
I'm dropping this series, I'm guessing you will send a v2 for the whole
set.
thanks,
greg k-h
