#include "llite_internal.h"
struct ll_sai_entry {
- struct list_head se_list;
+ cfs_list_t se_list;
unsigned int se_index;
int se_stat;
struct ptlrpc_request *se_req;
struct md_enqueue_info *se_minfo;
+ struct dentry *se_dentry;
+ struct inode *se_inode;
};
enum {
};
static unsigned int sai_generation = 0;
-static spinlock_t sai_generation_lock = SPIN_LOCK_UNLOCKED;
+static cfs_spinlock_t sai_generation_lock = CFS_SPIN_LOCK_UNLOCKED;
/**
* Check whether first entry was stated already or not.
- * No need to hold lli_lock, for:
+ * No need to hold lli_sa_lock, for:
* (1) it is me that remove entry from the list
* (2) the statahead thread only add new entry to the list
*/
struct ll_sai_entry *entry;
int rc = 0;
- if (!list_empty(&sai->sai_entries_stated)) {
- entry = list_entry(sai->sai_entries_stated.next,
- struct ll_sai_entry, se_list);
+ if (!cfs_list_empty(&sai->sai_entries_stated)) {
+ entry = cfs_list_entry(sai->sai_entries_stated.next,
+ struct ll_sai_entry, se_list);
if (entry->se_index == sai->sai_index_next)
rc = 1;
}
static inline int sa_received_empty(struct ll_statahead_info *sai)
{
- return list_empty(&sai->sai_entries_received);
+ return cfs_list_empty(&sai->sai_entries_received);
}
static inline int sa_not_full(struct ll_statahead_info *sai)
*/
static inline int sa_low_hit(struct ll_statahead_info *sai)
{
- return ((sai->sai_hit < 4 * sai->sai_miss && sai->sai_hit > 7) ||
+ return ((sai->sai_hit > 7 && sai->sai_hit < 4 * sai->sai_miss) ||
(sai->sai_consecutive_miss > 8));
}
+static inline int sa_skip_nolock(struct ll_statahead_info *sai)
+{
+ return (sai->sai_nolock >= 3);
+}
+
+static void ll_sai_entry_free(struct ll_sai_entry *entry)
+{
+ struct dentry *dentry = entry->se_dentry;
+ struct inode *inode = entry->se_inode;
+
+ if (dentry) {
+ struct ll_dentry_data *lld = ll_d2d(dentry);
+ struct ll_inode_info *lli;
+
+ entry->se_dentry = NULL;
+ LASSERT(inode != NULL);
+ lli = ll_i2info(inode);
+ if (!cfs_list_empty(&lli->lli_sa_dentry)) {
+ cfs_spin_lock(&lli->lli_sa_lock);
+ cfs_list_del_init(&lld->lld_sa_alias);
+ cfs_spin_unlock(&lli->lli_sa_lock);
+ }
+ dput(dentry);
+ }
+ if (inode) {
+ entry->se_inode = NULL;
+ iput(inode);
+ }
+ LASSERT(cfs_list_empty(&entry->se_list));
+ OBD_FREE_PTR(entry);
+}
+
/**
* process the deleted entry's member and free the entry.
* (1) release intent
*/
static void ll_sai_entry_cleanup(struct ll_sai_entry *entry, int free)
{
- struct ptlrpc_request *req = entry->se_req;
struct md_enqueue_info *minfo = entry->se_minfo;
+ struct ptlrpc_request *req = entry->se_req;
ENTRY;
if (minfo) {
- struct dentry *dentry = minfo->mi_dentry;
- struct lookup_intent *it = &minfo->mi_it;
-
entry->se_minfo = NULL;
- ll_intent_release(it);
+ ll_intent_release(&minfo->mi_it);
+ dput(minfo->mi_dentry);
+ iput(minfo->mi_dir);
OBD_FREE_PTR(minfo);
- dput(dentry);
}
if (req) {
entry->se_req = NULL;
ptlrpc_req_finished(req);
}
- if (free) {
- LASSERT(list_empty(&entry->se_list));
- OBD_FREE_PTR(entry);
- }
+ if (free)
+ ll_sai_entry_free(entry);
EXIT;
}
if (!sai)
return NULL;
- spin_lock(&sai_generation_lock);
+ cfs_spin_lock(&sai_generation_lock);
sai->sai_generation = ++sai_generation;
if (unlikely(sai_generation == 0))
sai->sai_generation = ++sai_generation;
- spin_unlock(&sai_generation_lock);
- atomic_set(&sai->sai_refcount, 1);
+ cfs_spin_unlock(&sai_generation_lock);
+ cfs_atomic_set(&sai->sai_refcount, 1);
sai->sai_max = LL_SA_RPC_MIN;
cfs_waitq_init(&sai->sai_waitq);
cfs_waitq_init(&sai->sai_thread.t_ctl_waitq);
return sai;
}
-static inline
+static inline
struct ll_statahead_info *ll_sai_get(struct ll_statahead_info *sai)
{
LASSERT(sai);
- atomic_inc(&sai->sai_refcount);
+ cfs_atomic_inc(&sai->sai_refcount);
return sai;
}
LASSERT(inode != NULL);
lli = ll_i2info(inode);
- if (atomic_dec_and_lock(&sai->sai_refcount, &lli->lli_lock)) {
+ LASSERT(lli->lli_sai == sai);
+
+ if (cfs_atomic_dec_and_test(&sai->sai_refcount)) {
struct ll_sai_entry *entry, *next;
+ cfs_spin_lock(&lli->lli_sa_lock);
+ if (unlikely(cfs_atomic_read(&sai->sai_refcount) > 0)) {
+ /* It is race case, the interpret callback just hold
+ * a reference count */
+ cfs_spin_unlock(&lli->lli_sa_lock);
+ EXIT;
+ return;
+ }
+
LASSERT(lli->lli_opendir_key == NULL);
lli->lli_sai = NULL;
lli->lli_opendir_pid = 0;
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
LASSERT(sa_is_stopped(sai));
PFID(&lli->lli_fid),
sai->sai_sent, sai->sai_replied);
- list_for_each_entry_safe(entry, next, &sai->sai_entries_sent,
- se_list) {
- list_del_init(&entry->se_list);
+ cfs_list_for_each_entry_safe(entry, next,
+ &sai->sai_entries_sent, se_list) {
+ cfs_list_del_init(&entry->se_list);
ll_sai_entry_cleanup(entry, 1);
}
- list_for_each_entry_safe(entry, next, &sai->sai_entries_received,
- se_list) {
- list_del_init(&entry->se_list);
+ cfs_list_for_each_entry_safe(entry, next,
+ &sai->sai_entries_received,
+ se_list) {
+ cfs_list_del_init(&entry->se_list);
ll_sai_entry_cleanup(entry, 1);
}
- list_for_each_entry_safe(entry, next, &sai->sai_entries_stated,
- se_list) {
- list_del_init(&entry->se_list);
+ cfs_list_for_each_entry_safe(entry, next,
+ &sai->sai_entries_stated,
+ se_list) {
+ cfs_list_del_init(&entry->se_list);
ll_sai_entry_cleanup(entry, 1);
}
- OBD_FREE_PTR(sai);
iput(inode);
+ OBD_FREE_PTR(sai);
}
EXIT;
}
CDEBUG(D_READA, "alloc sai entry %p index %u\n",
entry, index);
entry->se_index = index;
- entry->se_stat = SA_ENTRY_UNSTATED;
+ entry->se_stat = SA_ENTRY_UNSTATED;
- spin_lock(&lli->lli_lock);
- list_add_tail(&entry->se_list, &sai->sai_entries_sent);
- spin_unlock(&lli->lli_lock);
+ cfs_spin_lock(&lli->lli_sa_lock);
+ cfs_list_add_tail(&entry->se_list, &sai->sai_entries_sent);
+ cfs_spin_unlock(&lli->lli_sa_lock);
RETURN(entry);
}
* delete it from sai_entries_stated head when fini, it need not
* to process entry's member.
*/
-static void ll_sai_entry_fini(struct ll_statahead_info *sai)
+static int ll_sai_entry_fini(struct ll_statahead_info *sai)
{
struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
struct ll_sai_entry *entry;
+ int rc = 0;
ENTRY;
-
- spin_lock(&lli->lli_lock);
+
+ cfs_spin_lock(&lli->lli_sa_lock);
sai->sai_index_next++;
- if (likely(!list_empty(&sai->sai_entries_stated))) {
- entry = list_entry(sai->sai_entries_stated.next,
- struct ll_sai_entry, se_list);
+ if (likely(!cfs_list_empty(&sai->sai_entries_stated))) {
+ entry = cfs_list_entry(sai->sai_entries_stated.next,
+ struct ll_sai_entry, se_list);
if (entry->se_index < sai->sai_index_next) {
- list_del(&entry->se_list);
- OBD_FREE_PTR(entry);
+ cfs_list_del_init(&entry->se_list);
+ rc = entry->se_stat;
+ ll_sai_entry_free(entry);
}
- } else
+ } else {
LASSERT(sa_is_stopped(sai));
- spin_unlock(&lli->lli_lock);
+ }
+ cfs_spin_unlock(&lli->lli_sa_lock);
- EXIT;
+ RETURN(rc);
}
/**
- * inside lli_lock.
+ * inside lli_sa_lock.
* \retval NULL : can not find the entry in sai_entries_sent with the index
* \retval entry: find the entry in sai_entries_sent with the index
*/
struct ll_sai_entry *entry;
ENTRY;
- if (!list_empty(&sai->sai_entries_sent)) {
- list_for_each_entry(entry, &sai->sai_entries_sent, se_list) {
+ if (!cfs_list_empty(&sai->sai_entries_sent)) {
+ cfs_list_for_each_entry(entry, &sai->sai_entries_sent,
+ se_list) {
if (entry->se_index == index) {
entry->se_stat = stat;
entry->se_req = ptlrpc_request_addref(req);
entry->se_minfo = minfo;
RETURN(entry);
- } else if (entry->se_index > index)
+ } else if (entry->se_index > index) {
RETURN(NULL);
+ }
}
}
RETURN(NULL);
}
/**
- * inside lli_lock.
+ * inside lli_sa_lock.
* Move entry to sai_entries_received and
* insert it into sai_entries_received tail.
*/
static inline void
ll_sai_entry_to_received(struct ll_statahead_info *sai, struct ll_sai_entry *entry)
{
- if (!list_empty(&entry->se_list))
- list_del_init(&entry->se_list);
- list_add_tail(&entry->se_list, &sai->sai_entries_received);
+ if (!cfs_list_empty(&entry->se_list))
+ cfs_list_del_init(&entry->se_list);
+ cfs_list_add_tail(&entry->se_list, &sai->sai_entries_received);
}
/**
ll_sai_entry_cleanup(entry, 0);
- spin_lock(&lli->lli_lock);
- if (!list_empty(&entry->se_list))
- list_del_init(&entry->se_list);
+ cfs_spin_lock(&lli->lli_sa_lock);
+ if (!cfs_list_empty(&entry->se_list))
+ cfs_list_del_init(&entry->se_list);
+ /* stale entry */
if (unlikely(entry->se_index < sai->sai_index_next)) {
- spin_unlock(&lli->lli_lock);
- OBD_FREE_PTR(entry);
+ cfs_spin_unlock(&lli->lli_sa_lock);
+ ll_sai_entry_free(entry);
RETURN(0);
}
- list_for_each_entry_reverse(se, &sai->sai_entries_stated, se_list) {
+ cfs_list_for_each_entry_reverse(se, &sai->sai_entries_stated, se_list) {
if (se->se_index < entry->se_index) {
- list_add(&entry->se_list, &se->se_list);
- spin_unlock(&lli->lli_lock);
+ cfs_list_add(&entry->se_list, &se->se_list);
+ cfs_spin_unlock(&lli->lli_sa_lock);
RETURN(1);
}
}
/*
* I am the first entry.
*/
- list_add(&entry->se_list, &sai->sai_entries_stated);
- spin_unlock(&lli->lli_lock);
+ cfs_list_add(&entry->se_list, &sai->sai_entries_stated);
+ cfs_spin_unlock(&lli->lli_sa_lock);
RETURN(1);
}
struct ll_sai_entry *entry;
struct ptlrpc_request *req;
struct md_enqueue_info *minfo;
- struct dentry *dentry;
struct lookup_intent *it;
+ struct dentry *dentry;
int rc = 0;
struct mdt_body *body;
ENTRY;
- spin_lock(&lli->lli_lock);
+ cfs_spin_lock(&lli->lli_sa_lock);
LASSERT(!sa_received_empty(sai));
- entry = list_entry(sai->sai_entries_received.next, struct ll_sai_entry,
- se_list);
- list_del_init(&entry->se_list);
- spin_unlock(&lli->lli_lock);
+ entry = cfs_list_entry(sai->sai_entries_received.next,
+ struct ll_sai_entry, se_list);
+ cfs_list_del_init(&entry->se_list);
+ cfs_spin_unlock(&lli->lli_sa_lock);
if (unlikely(entry->se_index < sai->sai_index_next)) {
+ CWARN("Found stale entry: [index %u] [next %u]\n",
+ entry->se_index, sai->sai_index_next);
ll_sai_entry_cleanup(entry, 1);
RETURN(0);
}
req = entry->se_req;
minfo = entry->se_minfo;
- dentry = minfo->mi_dentry;
it = &minfo->mi_it;
+ dentry = minfo->mi_dentry;
body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
if (body == NULL)
* lookup.
*/
struct dentry *save = dentry;
+ __u32 bits = 0;
struct it_cb_data icbd = {
- .icbd_parent = dentry->d_parent->d_inode,
- .icbd_childp = &dentry
+ .icbd_parent = minfo->mi_dir,
+ .icbd_childp = &dentry,
+ .icbd_alias = &entry->se_inode,
+ .bits = &bits
};
LASSERT(fid_is_zero(&minfo->mi_data.op_fid2));
- /*
- * XXX: No fid in reply, this is probaly cross-ref case.
- * SA can't handle it yet.
- */
+ /* XXX: No fid in reply, this is probaly cross-ref case.
+ * SA can't handle it yet. */
if (body->valid & OBD_MD_MDS)
GOTO(out, rc = -EAGAIN);
+ /* Here dentry->d_inode might be NULL, because the entry may
+ * have been removed before we start doing stat ahead. */
+
+ /* BUG 15962, 21739: since statahead thread does not hold
+ * parent's i_mutex, it can not alias the dentry to inode.
+ * Here we just create/update inode in memory, and let the
+ * main "ls -l" thread to alias such dentry to the inode with
+ * parent's i_mutex held.
+ * On the other hand, we hold ldlm ibits lock for the inode
+ * yet, to allow other operations to cancel such lock in time,
+ * we should drop the ldlm lock reference count, then the main
+ * "ls -l" thread should check/get such ldlm ibits lock before
+ * aliasing such dentry to the inode later. If we don't do such
+ * drop here, it maybe cause deadlock with i_muext held by
+ * others, just like bug 21739. */
rc = ll_lookup_it_finish(req, it, &icbd);
- if (!rc)
- /*
- * Here dentry->d_inode might be NULL,
- * because the entry may have been removed before
- * we start doing stat ahead.
- */
- ll_lookup_finish_locks(it, dentry);
-
- if (dentry != save) {
- minfo->mi_dentry = dentry;
- dput(save);
+ if (entry->se_inode != NULL) {
+ struct ll_dentry_data *lld = ll_d2d(dentry);
+ struct ll_inode_info *sei = ll_i2info(entry->se_inode);
+
+ /* For statahead lookup case, both MDS_INODELOCK_LOOKUP
+ * and MDS_INODELOCK_UPDATE should be granted */
+ if (likely(bits & MDS_INODELOCK_LOOKUP &&
+ bits & MDS_INODELOCK_UPDATE)) {
+ /* the first dentry ref_count will be dropped by
+ * ll_sai_entry_to_stated(), so hold another ref
+ * in advance */
+ entry->se_dentry = dget(dentry);
+ cfs_spin_lock(&sei->lli_sa_lock);
+ cfs_list_add(&lld->lld_sa_alias,
+ &sei->lli_sa_dentry);
+ cfs_spin_unlock(&sei->lli_sa_lock);
+ sai->sai_nolock = 0;
+ } else {
+ iput(entry->se_inode);
+ entry->se_inode = NULL;
+ sai->sai_nolock++;
+ }
}
+ LASSERT(dentry == save);
+ ll_intent_drop_lock(it);
} else {
/*
* revalidate.
GOTO(out, rc);
}
- spin_lock(&ll_lookup_lock);
+ cfs_spin_lock(&ll_lookup_lock);
spin_lock(&dcache_lock);
lock_dentry(dentry);
__d_drop(dentry);
-#ifdef DCACHE_LUSTRE_INVALID
dentry->d_flags &= ~DCACHE_LUSTRE_INVALID;
-#endif
unlock_dentry(dentry);
d_rehash_cond(dentry, 0);
spin_unlock(&dcache_lock);
- spin_unlock(&ll_lookup_lock);
+ cfs_spin_unlock(&ll_lookup_lock);
ll_lookup_finish_locks(it, dentry);
}
EXIT;
out:
+ /* The "ll_sai_entry_to_stated()" will drop related ldlm ibits lock
+ * reference count with ll_intent_drop_lock() called in spite of the
+ * above operations failed or not. Do not worry about calling
+ * "ll_intent_drop_lock()" more than once. */
if (likely(ll_sai_entry_to_stated(sai, entry)))
cfs_waitq_signal(&sai->sai_waitq);
return rc;
struct md_enqueue_info *minfo,
int rc)
{
- struct dentry *dentry = minfo->mi_dentry;
struct lookup_intent *it = &minfo->mi_it;
- struct inode *dir = dentry->d_parent->d_inode;
+ struct dentry *dentry = minfo->mi_dentry;
+ struct inode *dir = minfo->mi_dir;
struct ll_inode_info *lli = ll_i2info(dir);
struct ll_statahead_info *sai;
struct ll_sai_entry *entry;
CDEBUG(D_READA, "interpret statahead %.*s rc %d\n",
dentry->d_name.len, dentry->d_name.name, rc);
- spin_lock(&lli->lli_lock);
+ cfs_spin_lock(&lli->lli_sa_lock);
+ /* stale entry */
if (unlikely(lli->lli_sai == NULL ||
lli->lli_sai->sai_generation != minfo->mi_generation)) {
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
ll_intent_release(it);
dput(dentry);
+ iput(dir);
OBD_FREE_PTR(minfo);
RETURN(-ESTALE);
} else {
sai = ll_sai_get(lli->lli_sai);
- if (rc || dir == NULL)
- rc = -ESTALE;
-
entry = ll_sai_entry_set(sai,
(unsigned int)(long)minfo->mi_cbdata,
- rc ? SA_ENTRY_UNSTATED :
- SA_ENTRY_STATED, req, minfo);
+ rc < 0 ? rc : SA_ENTRY_STATED, req,
+ minfo);
LASSERT(entry != NULL);
if (likely(sa_is_running(sai))) {
ll_sai_entry_to_received(sai, entry);
sai->sai_replied++;
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
cfs_waitq_signal(&sai->sai_thread.t_ctl_waitq);
} else {
- if (!list_empty(&entry->se_list))
- list_del_init(&entry->se_list);
+ if (!cfs_list_empty(&entry->se_list))
+ cfs_list_del_init(&entry->se_list);
sai->sai_replied++;
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
ll_sai_entry_cleanup(entry, 1);
}
ll_sai_put(sai);
struct ldlm_enqueue_info *einfo)
{
LASSERT(minfo && einfo);
+ iput(minfo->mi_dir);
capa_put(minfo->mi_data.op_capa1);
capa_put(minfo->mi_data.op_capa2);
OBD_FREE_PTR(minfo);
minfo->mi_it.it_op = IT_GETATTR;
minfo->mi_dentry = dentry;
+ minfo->mi_dir = igrab(dir);
minfo->mi_cb = ll_statahead_interpret;
minfo->mi_generation = lli->lli_sai->sai_generation;
minfo->mi_cbdata = (void *)(long)lli->lli_sai->sai_index;
* \retval 0 -- will send stat-ahead request
* \retval others -- prepare stat-ahead request failed
*/
-static int do_sa_revalidate(struct dentry *dentry)
+static int do_sa_revalidate(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
- struct inode *dir = dentry->d_parent->d_inode;
struct lookup_intent it = { .it_op = IT_GETATTR };
struct md_enqueue_info *minfo;
struct ldlm_enqueue_info *einfo;
int rc;
ENTRY;
- if (inode == NULL)
+ if (unlikely(inode == NULL))
RETURN(1);
if (d_mountpoint(dentry))
RETURN(1);
- if (dentry == dentry->d_sb->s_root)
+ if (unlikely(dentry == dentry->d_sb->s_root))
RETURN(1);
- rc = md_revalidate_lock(ll_i2mdexp(dir), &it, ll_inode2fid(inode));
+ rc = md_revalidate_lock(ll_i2mdexp(dir), &it, ll_inode2fid(inode),
+ NULL);
if (rc == 1) {
ll_intent_release(&it);
RETURN(1);
int rc;
ENTRY;
-#ifdef DCACHE_LUSTRE_INVALID
if (parent->d_flags & DCACHE_LUSTRE_INVALID) {
-#else
- if (d_unhashed(parent)) {
-#endif
CDEBUG(D_READA, "parent dentry@%p %.*s is "
"invalid, skip statahead\n",
parent, parent->d_name.len, parent->d_name.name);
ll_name2qstr(&name, entry_name, entry_name_len);
dentry = d_lookup(parent, &name);
if (!dentry) {
+ if (unlikely(sa_skip_nolock(sai))) {
+ CWARN("can not obtain lookup lock, skip the succeedent "
+ "lookup cases, will cause statahead miss, and "
+ "statahead maybe exit for that.\n");
+ GOTO(out, rc = -EAGAIN);
+ }
+
dentry = d_alloc(parent, &name);
if (dentry) {
- rc = do_sa_lookup(dir, dentry);
+ rc = ll_dops_init(dentry, 1);
+ if (!rc)
+ rc = do_sa_lookup(dir, dentry);
if (rc)
dput(dentry);
} else {
GOTO(out, rc = -ENOMEM);
}
} else {
- rc = do_sa_revalidate(dentry);
+ rc = do_sa_revalidate(dir, dentry);
if (rc)
dput(dentry);
}
if (rc) {
CDEBUG(D_READA, "set sai entry %p index %u stat %d rc %d\n",
se, se->se_index, se->se_stat, rc);
- se->se_stat = rc;
+ se->se_stat = rc < 0 ? rc : SA_ENTRY_STATED;
if (ll_sai_entry_to_stated(sai, se))
cfs_waitq_signal(&sai->sai_waitq);
} else {
return rc;
}
-struct ll_sa_thread_args {
- struct dentry *sta_parent;
- pid_t sta_pid;
-};
-
static int ll_statahead_thread(void *arg)
{
- struct ll_sa_thread_args *sta = arg;
- struct dentry *parent = dget(sta->sta_parent);
+ struct dentry *parent = (struct dentry *)arg;
struct inode *dir = parent->d_inode;
struct ll_inode_info *lli = ll_i2info(dir);
struct ll_sb_info *sbi = ll_i2sbi(dir);
- struct ll_statahead_info *sai;
- struct ptlrpc_thread *thread;
+ struct ll_statahead_info *sai = ll_sai_get(lli->lli_sai);
+ struct ptlrpc_thread *thread = &sai->sai_thread;
struct page *page;
__u64 pos = 0;
int first = 0;
struct ll_dir_chain chain;
ENTRY;
- spin_lock(&lli->lli_lock);
- if (unlikely(lli->lli_sai == NULL)) {
- spin_unlock(&lli->lli_lock);
- dput(parent);
- RETURN(-EAGAIN);
- } else {
- sai = ll_sai_get(lli->lli_sai);
- spin_unlock(&lli->lli_lock);
- }
-
{
char pname[16];
- snprintf(pname, 15, "ll_sa_%u", sta->sta_pid);
+ snprintf(pname, 15, "ll_sa_%u", lli->lli_opendir_pid);
cfs_daemonize(pname);
}
- thread = &sai->sai_thread;
- sbi->ll_sa_total++;
- spin_lock(&lli->lli_lock);
+ atomic_inc(&sbi->ll_sa_total);
+ cfs_spin_lock(&lli->lli_sa_lock);
thread->t_flags = SVC_RUNNING;
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
cfs_waitq_signal(&thread->t_ctl_waitq);
CDEBUG(D_READA, "start doing statahead for %s\n", parent->d_name.name);
if (IS_ERR(page)) {
rc = PTR_ERR(page);
- CERROR("error reading dir "DFID" at "LPU64"/%u: rc %d\n",
- PFID(ll_inode2fid(dir)), pos,
- sai->sai_index, rc);
+ CDEBUG(D_READA, "error reading dir "DFID" at "LPU64
+ "/%u: [rc %d] [parent %u]\n",
+ PFID(ll_inode2fid(dir)), pos, sai->sai_index,
+ rc, lli->lli_opendir_pid);
break;
}
char *name = ent->lde_name;
int namelen = le16_to_cpu(ent->lde_namelen);
- if (namelen == 0)
+ if (unlikely(namelen == 0))
/*
* Skip dummy record.
*/
out:
ll_dir_chain_fini(&chain);
- spin_lock(&lli->lli_lock);
+ cfs_spin_lock(&lli->lli_sa_lock);
thread->t_flags = SVC_STOPPED;
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
cfs_waitq_signal(&sai->sai_waitq);
cfs_waitq_signal(&thread->t_ctl_waitq);
ll_sai_put(sai);
if (unlikely(key == NULL))
return;
- spin_lock(&lli->lli_lock);
+ cfs_spin_lock(&lli->lli_sa_lock);
if (lli->lli_opendir_key != key || lli->lli_opendir_pid == 0) {
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
return;
}
if (!sa_is_stopped(lli->lli_sai)) {
thread->t_flags = SVC_STOPPING;
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
cfs_waitq_signal(&thread->t_ctl_waitq);
CDEBUG(D_READA, "stopping statahead thread, pid %d\n",
sa_is_stopped(lli->lli_sai),
&lwi);
} else {
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
}
/*
ll_sai_put(lli->lli_sai);
} else {
lli->lli_opendir_pid = 0;
- spin_unlock(&lli->lli_lock);
+ cfs_spin_unlock(&lli->lli_sa_lock);
}
}
*/
LS_FIRST_DE,
/**
- * the first hidden dirent, that is ".xxx
+ * the first hidden dirent, that is "."
*/
LS_FIRST_DOT_DE
};
struct lu_dirent *ent;
if (IS_ERR(page)) {
+ struct ll_inode_info *lli = ll_i2info(dir);
+
rc = PTR_ERR(page);
- CERROR("error reading dir "DFID" at "LPU64": rc %d\n",
- PFID(ll_inode2fid(dir)), pos, rc);
+ CERROR("error reading dir "DFID" at "LPU64": "
+ "[rc %d] [parent %u]\n",
+ PFID(ll_inode2fid(dir)), pos,
+ rc, lli->lli_opendir_pid);
break;
}
continue;
}
- if (target->len == namelen &&
- memcmp(target->name, name, namelen) == 0)
- rc = LS_FIRST_DE + dot_de;
- else
+ if (target->len != namelen ||
+ memcmp(target->name, name, namelen) != 0)
rc = LS_NONE_FIRST_DE;
+ else if (!dot_de)
+ rc = LS_FIRST_DE;
+ else
+ rc = LS_FIRST_DOT_DE;
+
ll_put_page(page);
GOTO(out, rc);
}
break;
} else if (1) {
/*
- * chain is exhausted
+ * chain is exhausted
* Normal case: continue to the next page.
*/
page = ll_get_dir_page(dir, pos, 1, &chain);
return rc;
}
+/*
+ * tgt: the dentry to be revalidate or lookup
+ * new: the dentry created by statahead
+ */
+static int is_same_dentry(struct dentry *tgt, struct dentry *new, int lookup)
+{
+ if (tgt == new) {
+ LASSERT(lookup == 0);
+ return 1;
+ }
+ if (tgt->d_parent != new->d_parent)
+ return 0;
+ if (tgt->d_name.hash != new->d_name.hash)
+ return 0;
+ if (tgt->d_name.len != new->d_name.len)
+ return 0;
+ if (memcmp(tgt->d_name.name, new->d_name.name, tgt->d_name.len) != 0)
+ return 0;
+ if (tgt->d_inode == NULL && lookup)
+ return 1;
+ if (tgt->d_inode)
+ LASSERTF(tgt->d_flags & DCACHE_LUSTRE_INVALID,
+ "[%.*s/%.*s] [%x %p "DFID"] [%x %p "DFID"]\n",
+ tgt->d_parent->d_name.len, tgt->d_parent->d_name.name,
+ tgt->d_name.len, tgt->d_name.name,
+ tgt->d_flags, tgt, PFID(ll_inode2fid(tgt->d_inode)),
+ new->d_flags, new, PFID(ll_inode2fid(new->d_inode)));
+ else
+ LASSERTF(tgt->d_flags & DCACHE_LUSTRE_INVALID,
+ "[%.*s/%.*s] [%x %p 0] [%x %p "DFID"]\n",
+ tgt->d_parent->d_name.len, tgt->d_parent->d_name.name,
+ tgt->d_name.len, tgt->d_name.name,
+ tgt->d_flags, tgt,
+ new->d_flags, new, PFID(ll_inode2fid(new->d_inode)));
+ return 0;
+}
+
/**
* Start statahead thread if this is the first dir entry.
* Otherwise if a thread is started already, wait it until it is ahead of me.
- * \retval 0 -- stat ahead thread process such dentry, for lookup, it miss
- * \retval 1 -- stat ahead thread process such dentry, for lookup, it hit
+ * \retval 0 -- stat ahead thread process such dentry, miss for lookup
+ * \retval 1 -- stat ahead thread process such dentry, hit for any case
* \retval -EEXIST -- stat ahead thread started, and this is the first dentry
* \retval -EBADFD -- statahead thread exit and not dentry available
* \retval -EAGAIN -- try to stat by caller
*/
int do_statahead_enter(struct inode *dir, struct dentry **dentryp, int lookup)
{
- struct ll_sb_info *sbi = ll_i2sbi(dir);
- struct ll_inode_info *lli = ll_i2info(dir);
- struct ll_statahead_info *sai = lli->lli_sai;
- struct ll_sa_thread_args sta;
- struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
+ struct ll_inode_info *lli;
+ struct ll_statahead_info *sai;
+ struct dentry *parent;
+ struct l_wait_info lwi = { 0 };
int rc = 0;
ENTRY;
+ LASSERT(dir != NULL);
+ lli = ll_i2info(dir);
LASSERT(lli->lli_opendir_pid == cfs_curproc_pid());
+ sai = lli->lli_sai;
if (sai) {
if (unlikely(sa_is_stopped(sai) &&
- list_empty(&sai->sai_entries_stated)))
+ cfs_list_empty(&sai->sai_entries_stated)))
RETURN(-EBADFD);
if ((*dentryp)->d_name.name[0] == '.') {
}
}
- if (ll_sai_entry_stated(sai)) {
- sbi->ll_sa_cached++;
- } else {
- sbi->ll_sa_blocked++;
+ if (!ll_sai_entry_stated(sai)) {
/*
* thread started already, avoid double-stat.
*/
+ lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
rc = l_wait_event(sai->sai_waitq,
ll_sai_entry_stated(sai) ||
sa_is_stopped(sai),
&lwi);
+ if (unlikely(rc == -EINTR))
+ RETURN(rc);
+ }
+
+ if (ll_sai_entry_stated(sai)) {
+ struct ll_sai_entry *entry;
+
+ entry = cfs_list_entry(sai->sai_entries_stated.next,
+ struct ll_sai_entry, se_list);
+ /* This is for statahead lookup */
+ if (entry->se_inode != NULL) {
+ struct lookup_intent it = {.it_op = IT_LOOKUP};
+ struct dentry *dchild = entry->se_dentry;
+ struct inode *ichild = entry->se_inode;
+ struct ll_dentry_data *lld = ll_d2d(dchild);
+ struct ll_inode_info *sei = ll_i2info(ichild);
+ struct dentry *save = dchild;
+ int invalid = 0;
+ __u32 bits = MDS_INODELOCK_LOOKUP |
+ MDS_INODELOCK_UPDATE;
+ int found = 0;
+
+ LASSERT(dchild != *dentryp);
+
+ if (!lookup)
+ mutex_lock(&dir->i_mutex);
+
+ /*
+ * Make sure dentry is still valid.
+ * For statahead lookup case, we need both
+ * LOOKUP lock and UPDATE lock which obtained
+ * by statahead thread originally.
+ *
+ * Consider following racer case:
+ * 1. statahead thread on client1 get lock with
+ * both LOOKUK and UPDATE bits for "aaa"
+ * 2. rename thread on client2 cancel such lock
+ * from client1, then rename "aaa" to "bbb"
+ * 3. ls thread on client1 obtain LOOKUP lock
+ * for "bbb" again
+ * 4. here the dentry "aaa" created by statahead
+ * thread should be invalid even related
+ * LOOKUP lock valid for the same inode
+ */
+ rc = md_revalidate_lock(ll_i2mdexp(dir), &it,
+ ll_inode2fid(ichild),
+ &bits);
+ cfs_spin_lock(&sei->lli_sa_lock);
+ if (!cfs_list_empty(&lld->lld_sa_alias))
+ cfs_list_del_init(&lld->lld_sa_alias);
+ else
+ invalid = 1;
+ cfs_spin_unlock(&sei->lli_sa_lock);
+ if (rc != 1)
+ /* Someone has cancelled the original
+ * lock before the real "revalidate"
+ * using it. Drop it. */
+ goto out_mutex;
+
+ if (invalid) {
+ /* Someone has cancelled the original
+ * lock, and reobtained it, the dentry
+ * maybe invalid anymore, Drop it. */
+ ll_intent_drop_lock(&it);
+ goto out_mutex;
+ }
+
+ ll_lookup_it_alias(&dchild, ichild, bits);
+ found = is_same_dentry(*dentryp, dchild, lookup);
+ ll_lookup_finish_locks(&it, dchild);
+ if (dchild != save)
+ dput(save);
+ ichild = NULL;
+
+out_mutex:
+ if (!lookup)
+ mutex_unlock(&dir->i_mutex);
+ /* Drop the inode reference count held by
+ * interpreter. */
+ if (ichild != NULL)
+ iput(ichild);
+
+ entry->se_dentry = NULL;
+ entry->se_inode = NULL;
+ if (found) {
+ if (lookup) {
+ LASSERT(*dentryp != dchild);
+ /* VFS will drop the reference
+ * count for dchild and *dentryp
+ * by itself. */
+ *dentryp = dchild;
+ } else {
+ LASSERT(*dentryp == dchild);
+ /* Drop the dentry reference
+ * count held by statahead. */
+ dput(dchild);
+ }
+ RETURN(1);
+ } else {
+ /* Drop the dentry reference count held
+ * by statahead. */
+ dput(dchild);
+ }
+ }
}
if (lookup) {
/*
* do nothing for revalidate.
*/
- RETURN(rc);
+ RETURN(0);
}
- /*
- * I am the "lli_opendir_pid" owner, only me can set "lli_sai".
- */
- LASSERT(lli->lli_sai == NULL);
-
+ /* I am the "lli_opendir_pid" owner, only me can set "lli_sai". */
rc = is_first_dirent(dir, *dentryp);
- if (rc == LS_NONE_FIRST_DE) {
- /*
- * It is not "ls -{a}l" operation, no need statahead for it.
- */
- spin_lock(&lli->lli_lock);
- lli->lli_opendir_key = NULL;
- lli->lli_opendir_pid = 0;
- spin_unlock(&lli->lli_lock);
- RETURN(-EBADF);
- }
+ if (rc == LS_NONE_FIRST_DE)
+ /* It is not "ls -{a}l" operation, no need statahead for it. */
+ GOTO(out, rc = -EAGAIN);
sai = ll_sai_alloc();
if (sai == NULL)
- RETURN(-ENOMEM);
+ GOTO(out, rc = -ENOMEM);
sai->sai_ls_all = (rc == LS_FIRST_DOT_DE);
sai->sai_inode = igrab(dir);
if (unlikely(sai->sai_inode == NULL)) {
- CWARN("Do not start stat ahead on dying inode "DFID" .\n",
+ CWARN("Do not start stat ahead on dying inode "DFID"\n",
PFID(&lli->lli_fid));
OBD_FREE_PTR(sai);
- RETURN(-ESTALE);
+ GOTO(out, rc = -ESTALE);
}
- LASSERT(sai->sai_inode == (*dentryp)->d_parent->d_inode);
+ /* get parent reference count here, and put it in ll_statahead_thread */
+ parent = dget((*dentryp)->d_parent);
+ if (unlikely(sai->sai_inode != parent->d_inode)) {
+ struct ll_inode_info *nlli = ll_i2info(parent->d_inode);
- sta.sta_parent = (*dentryp)->d_parent;
- sta.sta_pid = cfs_curproc_pid();
+ CWARN("Race condition, someone changed %.*s just now: "
+ "old parent "DFID", new parent "DFID"\n",
+ (*dentryp)->d_name.len, (*dentryp)->d_name.name,
+ PFID(&lli->lli_fid), PFID(&nlli->lli_fid));
+ dput(parent);
+ iput(sai->sai_inode);
+ OBD_FREE_PTR(sai);
+ RETURN(-EAGAIN);
+ }
lli->lli_sai = sai;
- rc = cfs_kernel_thread(ll_statahead_thread, &sta, 0);
+ rc = cfs_kernel_thread(ll_statahead_thread, parent, 0);
if (rc < 0) {
CERROR("can't start ll_sa thread, rc: %d\n", rc);
+ dput(parent);
lli->lli_opendir_key = NULL;
sai->sai_thread.t_flags = SVC_STOPPED;
ll_sai_put(sai);
RETURN(-EAGAIN);
}
- l_wait_event(sai->sai_thread.t_ctl_waitq,
+ l_wait_event(sai->sai_thread.t_ctl_waitq,
sa_is_running(sai) || sa_is_stopped(sai),
&lwi);
* lookup, and -EEXIST also indicates that this is the first dirent.
*/
RETURN(-EEXIST);
+
+out:
+ cfs_spin_lock(&lli->lli_sa_lock);
+ lli->lli_opendir_key = NULL;
+ lli->lli_opendir_pid = 0;
+ cfs_spin_unlock(&lli->lli_sa_lock);
+ return rc;
}
/**
* update hit/miss count.
*/
-void ll_statahead_exit(struct dentry *dentry, int result)
+void ll_statahead_exit(struct inode *dir, struct dentry *dentry, int result)
{
- struct dentry *parent = dentry->d_parent;
- struct ll_inode_info *lli = ll_i2info(parent->d_inode);
- struct ll_sb_info *sbi = ll_i2sbi(parent->d_inode);
- struct ll_statahead_info *sai = lli->lli_sai;
+ struct ll_inode_info *lli;
+ struct ll_statahead_info *sai;
+ struct ll_sb_info *sbi;
struct ll_dentry_data *ldd = ll_d2d(dentry);
+ int rc;
ENTRY;
- if (lli->lli_opendir_pid == cfs_curproc_pid() && sai) {
- if (result >= 1) {
- sbi->ll_sa_hit++;
- sai->sai_hit++;
- sai->sai_consecutive_miss = 0;
- sai->sai_max = min(2 * sai->sai_max, sbi->ll_sa_max);
- } else {
- sbi->ll_sa_miss++;
- sai->sai_miss++;
- sai->sai_consecutive_miss++;
- if (sa_low_hit(sai) && sa_is_running(sai)) {
- sbi->ll_sa_wrong++;
- CDEBUG(D_READA, "statahead for dir %.*s hit "
- "ratio too low: hit/miss %u/%u, "
- "sent/replied %u/%u. stopping statahead "
- "thread: pid %d\n",
- parent->d_name.len, parent->d_name.name,
- sai->sai_hit, sai->sai_miss,
- sai->sai_sent, sai->sai_replied,
- cfs_curproc_pid());
- spin_lock(&lli->lli_lock);
- if (!sa_is_stopped(sai))
- sai->sai_thread.t_flags = SVC_STOPPING;
- spin_unlock(&lli->lli_lock);
- }
+ LASSERT(dir != NULL);
+ lli = ll_i2info(dir);
+ LASSERT(lli->lli_opendir_pid == cfs_curproc_pid());
+ sai = lli->lli_sai;
+ LASSERT(sai != NULL);
+ sbi = ll_i2sbi(dir);
+
+ rc = ll_sai_entry_fini(sai);
+ /* rc == -ENOENT means such dentry was removed just between statahead
+ * readdir and pre-fetched, count it as hit.
+ *
+ * result == -ENOENT has two meanings:
+ * 1. such dentry was removed just between statahead pre-fetched and
+ * main process stat such dentry.
+ * 2. main process stat non-exist dentry.
+ * We can not distinguish such two cases, just count them as miss. */
+ if (result >= 1 || unlikely(rc == -ENOENT)) {
+ sai->sai_hit++;
+ sai->sai_consecutive_miss = 0;
+ sai->sai_max = min(2 * sai->sai_max, sbi->ll_sa_max);
+ } else {
+ sai->sai_miss++;
+ sai->sai_consecutive_miss++;
+ if (sa_low_hit(sai) && sa_is_running(sai)) {
+ atomic_inc(&sbi->ll_sa_wrong);
+ CDEBUG(D_READA, "Statahead for dir "DFID" hit ratio "
+ "too low: hit/miss %u/%u, sent/replied %u/%u, "
+ "stopping statahead thread: pid %d\n",
+ PFID(&lli->lli_fid), sai->sai_hit,
+ sai->sai_miss, sai->sai_sent,
+ sai->sai_replied, cfs_curproc_pid());
+ cfs_spin_lock(&lli->lli_sa_lock);
+ if (!sa_is_stopped(sai))
+ sai->sai_thread.t_flags = SVC_STOPPING;
+ cfs_spin_unlock(&lli->lli_sa_lock);
}
-
- if (!sa_is_stopped(sai))
- cfs_waitq_signal(&sai->sai_thread.t_ctl_waitq);
- ll_sai_entry_fini(sai);
- if (likely(ldd != NULL))
- ldd->lld_sa_generation = sai->sai_generation;
}
+
+ if (!sa_is_stopped(sai))
+ cfs_waitq_signal(&sai->sai_thread.t_ctl_waitq);
+ if (likely(ldd != NULL))
+ ldd->lld_sa_generation = sai->sai_generation;
+
EXIT;
}
git://git.whamcloud.com / fs / lustre-release.git / blobdiff