From: Niu Yawei <yawei.niu@xxxxxxxxx> Umount process relies on lu_site_purge(-1) to purge all objects before umount, however, if there happen to have a cache shrinker which calls lu_site_purge(nr) in parallel, some objects may still being freed by cache shrinker even after the lu_site_purge(-1) called by umount done. This can be simply fixed by serializing purge threads, since it doesn't make any sense to have them in parallel. Signed-off-by: Niu Yawei <yawei.niu@xxxxxxxxx> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5331 Reviewed-on: http://review.whamcloud.com/11099 Reviewed-by: Lai Siyao <lai.siyao@xxxxxxxxx> Reviewed-by: Mike Pershin <mike.pershin@xxxxxxxxx> Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx> Signed-off-by: James Simmons <jsimmons@xxxxxxxxxxxxx> --- drivers/staging/lustre/lustre/include/lu_object.h | 5 +++++ drivers/staging/lustre/lustre/obdclass/lu_object.c | 7 +++++++ 2 files changed, 12 insertions(+), 0 deletions(-) diff --git a/drivers/staging/lustre/lustre/include/lu_object.h b/drivers/staging/lustre/lustre/include/lu_object.h index 502bc41..fe40b42 100644 --- a/drivers/staging/lustre/lustre/include/lu_object.h +++ b/drivers/staging/lustre/lustre/include/lu_object.h @@ -623,6 +623,11 @@ struct lu_site { spinlock_t ls_ld_lock; /** + * Lock to serialize site purge. + */ + struct mutex ls_purge_mutex; + + /** * lu_site stats */ struct lprocfs_stats *ls_stats; diff --git a/drivers/staging/lustre/lustre/obdclass/lu_object.c b/drivers/staging/lustre/lustre/obdclass/lu_object.c index 9d1c96b..b6fd9af 100644 --- a/drivers/staging/lustre/lustre/obdclass/lu_object.c +++ b/drivers/staging/lustre/lustre/obdclass/lu_object.c @@ -354,6 +354,11 @@ int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr) start = s->ls_purge_start; bnr = (nr == ~0) ? -1 : nr / CFS_HASH_NBKT(s->ls_obj_hash) + 1; again: + /* + * It doesn't make any sense to make purge threads parallel, that can + * only bring troubles to us. See LU-5331. + */ + mutex_lock(&s->ls_purge_mutex); did_sth = 0; cfs_hash_for_each_bucket(s->ls_obj_hash, &bd, i) { if (i < start) @@ -399,6 +404,7 @@ int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr) if (nr == 0) break; } + mutex_unlock(&s->ls_purge_mutex); if (nr != 0 && did_sth && start != 0) { start = 0; /* restart from the first bucket */ @@ -983,6 +989,7 @@ int lu_site_init(struct lu_site *s, struct lu_device *top) char name[16]; memset(s, 0, sizeof(*s)); + mutex_init(&s->ls_purge_mutex); snprintf(name, 16, "lu_site_%s", top->ld_type->ldt_name); for (bits = lu_htable_order(top); bits >= LU_SITE_BITS_MIN; bits--) { s->ls_obj_hash = cfs_hash_create(name, bits, bits, -- 1.7.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
