From 0d4dbdda134a9fa1e349d6c2dd10257e7638834a Mon Sep 17 00:00:00 2001 From: fanyong Date: Thu, 10 Jul 2008 07:30:48 +0000 Subject: [PATCH] Branch HEAD b=15927 i=johann i=huanghua replace ptlrpcd with the statahead thread to interpret the async statahead RPC callback. --- lustre/llite/dcache.c | 2 +- lustre/llite/llite_internal.h | 10 +- lustre/llite/statahead.c | 683 +++++++++++++++++++++++++++++------------- 3 files changed, 489 insertions(+), 206 deletions(-) diff --git a/lustre/llite/dcache.c b/lustre/llite/dcache.c index 4d8b687..fc2ee94 100644 --- a/lustre/llite/dcache.c +++ b/lustre/llite/dcache.c @@ -37,7 +37,7 @@ #include "llite_internal.h" /* should NOT be called with the dcache lock, see fs/dcache.c */ -static void ll_release(struct dentry *de) +void ll_release(struct dentry *de) { struct ll_dentry_data *lld; ENTRY; diff --git a/lustre/llite/llite_internal.h b/lustre/llite/llite_internal.h index c37af6b..e699656 100644 --- a/lustre/llite/llite_internal.h +++ b/lustre/llite/llite_internal.h @@ -666,6 +666,7 @@ int ll_extent_lock_cancel_cb(struct ldlm_lock *lock, struct ldlm_lock_desc *new, extern struct dentry_operations ll_init_d_ops; extern struct dentry_operations ll_d_ops; extern struct dentry_operations ll_fini_d_ops; +void ll_release(struct dentry *de); void ll_intent_drop_lock(struct lookup_intent *); void ll_intent_release(struct lookup_intent *); int ll_drop_dentry(struct dentry *dentry); @@ -910,6 +911,7 @@ void et_fini(struct eacl_table *et); /* per inode struct, for dir only */ struct ll_statahead_info { struct inode *sai_inode; + struct dentry *sai_first; /* first dentry item */ unsigned int sai_generation; /* generation for statahead */ atomic_t sai_refcount; /* when access this struct, hold * refcount */ @@ -918,6 +920,8 @@ struct ll_statahead_info { * reply */ unsigned int sai_max; /* max ahead of lookup */ unsigned int sai_index; /* index of statahead entry */ + unsigned int sai_index_next; /* index for the next statahead + * entry to be stated */ unsigned int sai_hit; /* hit count */ unsigned int sai_miss; /* miss count: * for "ls -al" case, it includes @@ -935,11 +939,13 @@ struct ll_statahead_info { * hidden entries */ cfs_waitq_t sai_waitq; /* stat-ahead wait queue */ struct ptlrpc_thread sai_thread; /* stat-ahead thread */ - struct list_head sai_entries; /* stat-ahead entries */ + struct list_head sai_entries_sent; /* entries sent out */ + struct list_head sai_entries_received; /* entries returned */ + struct list_head sai_entries_stated; /* entries stated */ }; int do_statahead_enter(struct inode *dir, struct dentry **dentry, int lookup); -void ll_statahead_exit(struct dentry *dentry, int result); +int ll_statahead_exit(struct dentry *dentry, int result); void ll_stop_statahead(struct inode *inode, void *key); static inline diff --git a/lustre/llite/statahead.c b/lustre/llite/statahead.c index c2780ca..77dd034 100644 --- a/lustre/llite/statahead.c +++ b/lustre/llite/statahead.c @@ -38,6 +38,8 @@ struct ll_sai_entry { struct list_head se_list; unsigned int se_index; int se_stat; + struct ptlrpc_request *se_req; + struct md_enqueue_info *se_minfo; }; enum { @@ -45,9 +47,100 @@ enum { SA_ENTRY_STATED }; +struct dentry_operations ll_sai_d_ops = { + .d_release = ll_release, +}; + static unsigned int sai_generation = 0; static spinlock_t sai_generation_lock = SPIN_LOCK_UNLOCKED; +/** + * Check whether first entry was stated already or not. + * No need to hold lli_lock, for: + * (1) it is me that remove entry from the list + * (2) the statahead thread only add new entry to the list + */ +static int ll_sai_entry_stated(struct ll_statahead_info *sai) +{ + 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 (entry->se_index == sai->sai_index_next) + rc = 1; + } + return rc; +} + +static inline int sa_received_empty(struct ll_statahead_info *sai) +{ + return list_empty(&sai->sai_entries_received); +} + +static inline int sa_not_full(struct ll_statahead_info *sai) +{ + return sai->sai_index < sai->sai_hit + sai->sai_miss + sai->sai_max; +} + +static inline int sa_is_running(struct ll_statahead_info *sai) +{ + return !!(sai->sai_thread.t_flags & SVC_RUNNING); +} + +static inline int sa_is_stopping(struct ll_statahead_info *sai) +{ + return !!(sai->sai_thread.t_flags & SVC_STOPPING); +} + +static inline int sa_is_stopped(struct ll_statahead_info *sai) +{ + return !!(sai->sai_thread.t_flags & SVC_STOPPED); +} + +/** + * (1) hit ratio less than 80% + * or + * (2) consecutive miss more than 8 + */ +static inline int sa_low_hit(struct ll_statahead_info *sai) +{ + return ((sai->sai_hit < 4 * sai->sai_miss && sai->sai_hit > 7) || + (sai->sai_consecutive_miss > 8)); +} + +/** + * process the deleted entry's member and free the entry. + * (1) release intent + * (2) free md_enqueue_info + * (3) drop dentry's ref count + * (4) release request's ref count + */ +static void ll_sai_entry_cleanup(struct ll_sai_entry *entry) +{ + struct ptlrpc_request *req = entry->se_req; + struct md_enqueue_info *minfo = entry->se_minfo; + ENTRY; + + if (minfo) { + struct dentry *dentry = minfo->mi_dentry; + struct lookup_intent *it = &minfo->mi_it; + + entry->se_minfo = NULL; + ll_intent_release(it); + OBD_FREE_PTR(minfo); + dput(dentry); + } + if (req) { + entry->se_req = NULL; + ptlrpc_req_finished(req); + } + OBD_FREE_PTR(entry); + + EXIT; +} + static struct ll_statahead_info *ll_sai_alloc(void) { struct ll_statahead_info *sai; @@ -65,7 +158,9 @@ static struct ll_statahead_info *ll_sai_alloc(void) sai->sai_max = LL_SA_RPC_MIN; cfs_waitq_init(&sai->sai_waitq); cfs_waitq_init(&sai->sai_thread.t_ctl_waitq); - CFS_INIT_LIST_HEAD(&sai->sai_entries); + CFS_INIT_LIST_HEAD(&sai->sai_entries_sent); + CFS_INIT_LIST_HEAD(&sai->sai_entries_received); + CFS_INIT_LIST_HEAD(&sai->sai_entries_stated); return sai; } @@ -89,7 +184,7 @@ static void ll_sai_put(struct ll_statahead_info *sai) lli->lli_sai = NULL; spin_unlock(&lli->lli_lock); - LASSERT(sai->sai_thread.t_flags & SVC_STOPPED); + LASSERT(sa_is_stopped(sai)); if (sai->sai_sent > sai->sai_replied) CDEBUG(D_READA,"statahead for dir "DFID" does not " @@ -97,19 +192,33 @@ static void ll_sai_put(struct ll_statahead_info *sai) PFID(&lli->lli_fid), sai->sai_sent, sai->sai_replied); - list_for_each_entry_safe(entry, next, &sai->sai_entries, + list_for_each_entry_safe(entry, next, &sai->sai_entries_sent, se_list) { list_del(&entry->se_list); - OBD_FREE_PTR(entry); + ll_sai_entry_cleanup(entry); } + list_for_each_entry_safe(entry, next, &sai->sai_entries_received, + se_list) { + list_del(&entry->se_list); + ll_sai_entry_cleanup(entry); + } + list_for_each_entry_safe(entry, next, &sai->sai_entries_stated, + se_list) { + list_del(&entry->se_list); + ll_sai_entry_cleanup(entry); + } + dput(sai->sai_first); OBD_FREE_PTR(sai); iput(inode); } EXIT; } +/** + * insert it into sai_entries_sent tail when init. + */ static struct ll_sai_entry * -ll_sai_entry_get(struct ll_statahead_info *sai, unsigned int index, int stat) +ll_sai_entry_init(struct ll_statahead_info *sai, unsigned int index) { struct ll_inode_info *lli = ll_i2info(sai->sai_inode); struct ll_sai_entry *entry; @@ -119,126 +228,162 @@ ll_sai_entry_get(struct ll_statahead_info *sai, unsigned int index, int stat) if (entry == NULL) RETURN(ERR_PTR(-ENOMEM)); - CDEBUG(D_READA, "alloc sai entry %p index %u, stat %d\n", - entry, index, stat); + CDEBUG(D_READA, "alloc sai entry %p index %u\n", + entry, index); entry->se_index = index; - entry->se_stat = stat; + entry->se_stat = SA_ENTRY_UNSTATED; spin_lock(&lli->lli_lock); - list_add_tail(&entry->se_list, &sai->sai_entries); + list_add_tail(&entry->se_list, &sai->sai_entries_sent); spin_unlock(&lli->lli_lock); RETURN(entry); } -/* inside lli_lock - * return value: - * 0: can not find the entry with the index - * 1: it is the first entry - * 2: it is not the first entry */ -static int -ll_sai_entry_set(struct ll_statahead_info *sai, unsigned int index, int stat) +/** + * 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) { - struct ll_sai_entry *entry; - int rc = 0; + struct ll_inode_info *lli = ll_i2info(sai->sai_inode); + struct ll_sai_entry *entry; ENTRY; - - if (list_empty(&sai->sai_entries)) - RETURN(0); - - entry = list_entry(sai->sai_entries.next, struct ll_sai_entry, se_list); - if (entry->se_index == index) - GOTO(out, rc = 1); - - while (entry->se_list.next != &sai->sai_entries && - entry->se_index < index) { - entry = list_entry(entry->se_list.next, struct ll_sai_entry, - se_list); - if (entry->se_index == index) - GOTO(out, rc = 2); - } + + spin_lock(&lli->lli_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 (entry->se_index < sai->sai_index_next) { + list_del(&entry->se_list); + OBD_FREE_PTR(entry); + } + } else + LASSERT(sa_is_stopped(sai)); + spin_unlock(&lli->lli_lock); EXIT; - -out: - if (rc) { - LASSERT(entry->se_stat == SA_ENTRY_UNSTATED); - entry->se_stat = stat; - } - - return rc; } -/* Check whether first entry was stated already or not. - * No need to hold lli_lock, for: - * (1) it is me that remove entry from the list (ll_sai_entry_put) - * (2) the statahead thread only add new entry to the list tail */ -static int ll_sai_entry_stated(struct ll_statahead_info *sai) +/** + * inside lli_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 + */ +static struct ll_sai_entry * +ll_sai_entry_set(struct ll_statahead_info *sai, unsigned int index, int stat, + struct ptlrpc_request *req, struct md_enqueue_info *minfo) { - struct ll_sai_entry *entry; - int rc = 0; + struct ll_sai_entry *entry; ENTRY; - if (!list_empty(&sai->sai_entries)) { - entry = list_entry(sai->sai_entries.next, struct ll_sai_entry, - se_list); - rc = (entry->se_stat != SA_ENTRY_UNSTATED); + if (!list_empty(&sai->sai_entries_sent)) { + 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) + RETURN(NULL); + } } + RETURN(NULL); +} - RETURN(rc); +/** + * inside lli_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); } -static void ll_sai_entry_put(struct ll_statahead_info *sai) +/** + * Move entry to sai_entries_stated and + * sort with the index. + */ +static int +ll_sai_entry_to_stated(struct ll_statahead_info *sai, struct ll_sai_entry *entry) { struct ll_inode_info *lli = ll_i2info(sai->sai_inode); - struct ll_sai_entry *entry; + struct ll_sai_entry *se; ENTRY; spin_lock(&lli->lli_lock); - if (!list_empty(&sai->sai_entries)) { - entry = list_entry(sai->sai_entries.next, - struct ll_sai_entry, se_list); - list_del(&entry->se_list); - OBD_FREE_PTR(entry); + if (!list_empty(&entry->se_list)) + list_del_init(&entry->se_list); + + if (unlikely(entry->se_index < sai->sai_index_next)) { + spin_unlock(&lli->lli_lock); + ll_sai_entry_cleanup(entry); + RETURN(0); } - spin_unlock(&lli->lli_lock); - EXIT; + 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); + RETURN(1); + } + } + + /* + * I am the first entry. + */ + list_add(&entry->se_list, &sai->sai_entries_stated); + spin_unlock(&lli->lli_lock); + RETURN(1); } -/* finish lookup/revalidate */ -static int ll_statahead_interpret(struct ptlrpc_request *req, - struct md_enqueue_info *minfo, - int rc) +/** + * finish lookup/revalidate. + */ +static int do_statahead_interpret(struct ll_statahead_info *sai) { - struct lookup_intent *it = &minfo->mi_it; - struct dentry *dentry = minfo->mi_dentry; - struct inode *dir = dentry->d_parent->d_inode; - struct ll_inode_info *lli = ll_i2info(dir); - struct ll_statahead_info *sai = NULL; + struct ll_inode_info *lli = ll_i2info(sai->sai_inode); + struct ll_sai_entry *entry; + struct ptlrpc_request *req; + struct md_enqueue_info *minfo; + struct dentry *dentry; + struct lookup_intent *it; + int rc = 0; ENTRY; - CDEBUG(D_READA, "interpret statahead %.*s rc %d\n", - dentry->d_name.len, dentry->d_name.name, rc); - spin_lock(&lli->lli_lock); - if (unlikely(lli->lli_sai == NULL || - lli->lli_sai->sai_generation != minfo->mi_generation)) { - spin_unlock(&lli->lli_lock); - GOTO(out_free, rc = -ESTALE); - } else { - sai = ll_sai_get(lli->lli_sai); - spin_unlock(&lli->lli_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); + + if (unlikely(entry->se_index < sai->sai_index_next)) { + ll_sai_entry_cleanup(entry); + RETURN(0); } - if (rc || dir == NULL) - GOTO(out, rc); + req = entry->se_req; + minfo = entry->se_minfo; + dentry = minfo->mi_dentry; + it = &minfo->mi_it; + + if (entry->se_stat != SA_ENTRY_STATED) + GOTO(out, rc = entry->se_stat); if (dentry->d_inode == NULL) { - /* lookup */ + /* + * lookup. + */ struct dentry *save = dentry; struct it_cb_data icbd = { - .icbd_parent = dir, + .icbd_parent = dentry->d_parent->d_inode, .icbd_childp = &dentry }; @@ -246,15 +391,21 @@ static int ll_statahead_interpret(struct ptlrpc_request *req, rc = ll_lookup_it_finish(req, it, &icbd); if (!rc) - /* Here dentry->d_inode might be NULL, + /* + * Here dentry->d_inode might be NULL, * because the entry may have been removed before - * we start doing stat ahead. */ + * we start doing stat ahead. + */ ll_lookup_finish_locks(it, dentry); - if (dentry != save) + if (dentry != save) { + minfo->mi_dentry = dentry; dput(save); + } } else { - /* revalidate */ + /* + * revalidate. + */ struct mdt_body *body; body = lustre_msg_buf(req->rq_repmsg, DLM_REPLY_REC_OFF, @@ -285,34 +436,65 @@ static int ll_statahead_interpret(struct ptlrpc_request *req, EXIT; out: - if (sai != NULL) { - int first; + if (likely(ll_sai_entry_to_stated(sai, entry))) { + entry->se_minfo = NULL; + entry->se_req = NULL; + cfs_waitq_signal(&sai->sai_waitq); + ll_intent_release(it); + OBD_FREE_PTR(minfo); + dput(dentry); + ptlrpc_req_finished(req); + } + return rc; +} - sai->sai_replied++; - spin_lock(&lli->lli_lock); - first = ll_sai_entry_set(sai, - (unsigned int)(long)minfo->mi_cbdata, - SA_ENTRY_STATED); +static int ll_statahead_interpret(struct ptlrpc_request *req, + 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 ll_inode_info *lli = ll_i2info(dir); + struct ll_statahead_info *sai; + struct ll_sai_entry *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); + if (unlikely(lli->lli_sai == NULL || + lli->lli_sai->sai_generation != minfo->mi_generation)) { spin_unlock(&lli->lli_lock); - if (first == 1) - /* wake up the "ls -l" process only when the first entry - * returned. */ - cfs_waitq_signal(&sai->sai_waitq); - else if (first == 0) - CDEBUG(D_READA, "can't find sai entry for dir " - DFID" generation %u index %u\n", - PFID(&lli->lli_fid), - minfo->mi_generation, - (unsigned int)(long)minfo->mi_cbdata); + ll_intent_release(it); + dput(dentry); + OBD_FREE_PTR(minfo); + RETURN(-ESTALE); + } else { + sai = lli->lli_sai; + if (rc || dir == NULL) + rc = -ESTALE; - ll_sai_put(sai); + entry = ll_sai_entry_set(sai, + (unsigned int)(long)minfo->mi_cbdata, + rc ? SA_ENTRY_UNSTATED : + 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_waitq_signal(&sai->sai_thread.t_ctl_waitq); + } else { + if (!list_empty(&entry->se_list)) + list_del_init(&entry->se_list); + sai->sai_replied++; + spin_unlock(&lli->lli_lock); + ll_sai_entry_cleanup(entry); + } + RETURN(rc); } -out_free: - ll_intent_release(it); - OBD_FREE_PTR(minfo); - - dput(dentry); - return rc; } static void sa_args_fini(struct md_enqueue_info *minfo, @@ -325,13 +507,15 @@ static void sa_args_fini(struct md_enqueue_info *minfo, OBD_FREE_PTR(einfo); } -/* There is race condition between "capa_put" and "ll_statahead_interpret" for +/** + * There is race condition between "capa_put" and "ll_statahead_interpret" for * accessing "op_data.op_capa[1,2]" as following: * "capa_put" releases "op_data.op_capa[1,2]"'s reference count after calling * "md_intent_getattr_async". But "ll_statahead_interpret" maybe run first, and * fill "op_data.op_capa[1,2]" as POISON, then cause "capa_put" access invalid * "ocapa". So here reserve "op_data.op_capa[1,2]" in "pcapa" before calling - * "md_intent_getattr_async". */ + * "md_intent_getattr_async". + */ static int sa_args_init(struct inode *dir, struct dentry *dentry, struct md_enqueue_info **pmi, struct ldlm_enqueue_info **pei, @@ -382,7 +566,9 @@ static int sa_args_init(struct inode *dir, struct dentry *dentry, return 0; } -/* similar to ll_lookup_it(). */ +/** + * similar to ll_lookup_it(). + */ static int do_sa_lookup(struct inode *dir, struct dentry *dentry) { struct md_enqueue_info *minfo; @@ -406,11 +592,12 @@ static int do_sa_lookup(struct inode *dir, struct dentry *dentry) RETURN(rc); } -/* similar to ll_revalidate_it(). - * return value: - * 1 -- dentry valid - * 0 -- will send stat-ahead request - * others -- prepare stat-ahead request failed */ +/** + * similar to ll_revalidate_it(). + * \retval 1 -- dentry valid + * \retval 0 -- will send stat-ahead request + * \retval others -- prepare stat-ahead request failed + */ static int do_sa_revalidate(struct dentry *dentry) { struct inode *inode = dentry->d_inode; @@ -489,7 +676,7 @@ static int ll_statahead_one(struct dentry *parent, const char* entry_name, RETURN(-EINVAL); } - se = ll_sai_entry_get(sai, sai->sai_index, SA_ENTRY_UNSTATED); + se = ll_sai_entry_init(sai, sai->sai_index); if (IS_ERR(se)) RETURN(PTR_ERR(se)); @@ -517,7 +704,8 @@ out: 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; - cfs_waitq_signal(&sai->sai_waitq); + if (ll_sai_entry_to_stated(sai, se)) + cfs_waitq_signal(&sai->sai_waitq); } else { sai->sai_sent++; } @@ -526,25 +714,6 @@ out: return rc; } -static inline int sa_check_stop(struct ll_statahead_info *sai) -{ - return !!(sai->sai_thread.t_flags & SVC_STOPPING); -} - -static inline int sa_not_full(struct ll_statahead_info *sai) -{ - return sai->sai_index < sai->sai_hit + sai->sai_miss + sai->sai_max; -} - -/* (1) hit ratio less than 80% - * or - * (2) consecutive miss more than 8 */ -static inline int sa_low_hit(struct ll_statahead_info *sai) -{ - return ((sai->sai_hit < 4 * sai->sai_miss && sai->sai_hit > 7) || - (sai->sai_consecutive_miss > 8)); -} - struct ll_sa_thread_args { struct dentry *sta_parent; pid_t sta_pid; @@ -583,6 +752,7 @@ static int ll_statahead_thread(void *arg) page = ll_get_dir_page(dir, pos, 0, &chain); while (1) { + struct l_wait_info lwi = { 0 }; struct lu_dirpage *dp; struct lu_dirent *ent; @@ -597,43 +767,63 @@ static int ll_statahead_thread(void *arg) dp = page_address(page); for (ent = lu_dirent_start(dp); ent != NULL; ent = lu_dirent_next(ent)) { - struct l_wait_info lwi = { 0 }; char *name = ent->lde_name; int namelen = le16_to_cpu(ent->lde_namelen); if (namelen == 0) - /* Skip dummy record. */ + /* + * Skip dummy record. + */ continue; if (name[0] == '.') { if (namelen == 1) { - /* skip . */ + /* + * skip "." + */ continue; } else if (name[1] == '.' && namelen == 2) { - /* skip .. */ + /* + * skip ".." + */ continue; } else if (!sai->sai_ls_all) { - /* skip hidden files */ + /* + * skip hidden files. + */ sai->sai_skip_hidden++; continue; } } - /* don't stat-ahead first entry */ + /* + * don't stat-ahead first entry. + */ if (unlikely(!first)) { first++; continue; } +keep_de: l_wait_event(thread->t_ctl_waitq, - sa_check_stop(sai) || sa_not_full(sai), + !sa_is_running(sai) || sa_not_full(sai) || + !sa_received_empty(sai), &lwi); - if (unlikely(sa_check_stop(sai))) { + while (!sa_received_empty(sai) && sa_is_running(sai)) + do_statahead_interpret(sai); + + if (unlikely(!sa_is_running(sai))) { ll_put_page(page); GOTO(out, rc); } + if (!sa_not_full(sai)) + /* + * do not skip the current de. + */ + goto keep_de; + rc = ll_statahead_one(parent, name, namelen); if (rc < 0) { ll_put_page(page); @@ -643,13 +833,31 @@ static int ll_statahead_thread(void *arg) pos = le64_to_cpu(dp->ldp_hash_end); ll_put_page(page); if (pos == DIR_END_OFF) { - /* End of directory reached. */ - break; - } else if (1 /* chain is exhausted*/) { - /* Normal case: continue to the next page. */ + /* + * End of directory reached. + */ + while (1) { + l_wait_event(thread->t_ctl_waitq, + !sa_is_running(sai) || + !sa_received_empty(sai) || + sai->sai_sent == sai->sai_replied, + &lwi); + if (!sa_received_empty(sai) && + sa_is_running(sai)) + do_statahead_interpret(sai); + else + GOTO(out, rc); + } + } else if (1) { + /* + * chain is exhausted. + * Normal case: continue to the next page. + */ page = ll_get_dir_page(dir, pos, 1, &chain); } else { - /* go into overflow page. */ + /* + * go into overflow page. + */ } } EXIT; @@ -668,7 +876,9 @@ out: return rc; } -/* called in ll_file_release() */ +/** + * called in ll_file_release(). + */ void ll_stop_statahead(struct inode *inode, void *key) { struct ll_inode_info *lli = ll_i2info(inode); @@ -688,7 +898,7 @@ void ll_stop_statahead(struct inode *inode, void *key) struct l_wait_info lwi = { 0 }; thread = &lli->lli_sai->sai_thread; - if (!(thread->t_flags & SVC_STOPPED)) { + if (!sa_is_stopped(lli->lli_sai)) { thread->t_flags = SVC_STOPPING; spin_unlock(&lli->lli_lock); cfs_waitq_signal(&thread->t_ctl_waitq); @@ -696,15 +906,17 @@ void ll_stop_statahead(struct inode *inode, void *key) CDEBUG(D_READA, "stopping statahead thread, pid %d\n", cfs_curproc_pid()); l_wait_event(thread->t_ctl_waitq, - thread->t_flags & SVC_STOPPED, + sa_is_stopped(lli->lli_sai), &lwi); } else { spin_unlock(&lli->lli_lock); } - /* Put the ref which was held when first statahead_enter. + /* + * Put the ref which was held when first statahead_enter. * It maybe not the last ref for some statahead requests - * maybe inflight. */ + * maybe inflight. + */ ll_sai_put(lli->lli_sai); return; } @@ -712,9 +924,18 @@ void ll_stop_statahead(struct inode *inode, void *key) } enum { - LS_NONE_FIRST_DE = 0, /* not first dirent, or is "." */ - LS_FIRST_DE, /* the first non-hidden dirent */ - LS_FIRST_DOT_DE /* the first hidden dirent, that is ".xxx" */ + /** + * not first dirent, or is "." + */ + LS_NONE_FIRST_DE = 0, + /** + * the first non-hidden dirent + */ + LS_FIRST_DE, + /** + * the first hidden dirent, that is ".xxx + */ + LS_FIRST_DOT_DE }; static int is_first_dirent(struct inode *dir, struct dentry *dentry) @@ -748,15 +969,21 @@ static int is_first_dirent(struct inode *dir, struct dentry *dentry) int namelen = le16_to_cpu(ent->lde_namelen); if (namelen == 0) - /* Skip dummy record. */ + /* + * skip dummy record. + */ continue; if (name[0] == '.') { if (namelen == 1) - /* skip . */ + /* + * skip "." + */ continue; else if (name[1] == '.' && namelen == 2) - /* skip .. */ + /* + * skip ".." + */ continue; else dot_de = 1; @@ -782,13 +1009,20 @@ static int is_first_dirent(struct inode *dir, struct dentry *dentry) pos = le64_to_cpu(dp->ldp_hash_end); ll_put_page(page); if (pos == DIR_END_OFF) { - /* End of directory reached. */ + /* + * End of directory reached. + */ break; - } else if (1 /* chain is exhausted*/) { - /* Normal case: continue to the next page. */ + } else if (1) { + /* + * chain is exhausted + * Normal case: continue to the next page. + */ page = ll_get_dir_page(dir, pos, 1, &chain); } else { - /* go into overflow page. */ + /* + * go into overflow page. + */ } } EXIT; @@ -798,14 +1032,15 @@ out: return rc; } -/* Start statahead thread if this is the first dir entry. +/** + * 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. - * Return value: - * 0 -- stat ahead thread process such dentry, for lookup, it miss - * 1 -- stat ahead thread process such dentry, for lookup, it hit - * -EEXIST -- stat ahead thread started, and this is the first dentry - * -EBADFD -- statahead thread exit and not dentry available - * others -- error */ + * \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 -EEXIST -- stat ahead thread started, and this is the first dentry + * \retval -EBADFD -- statahead thread exit and not dentry available + * \retval others -- error + */ int do_statahead_enter(struct inode *dir, struct dentry **dentryp, int lookup) { struct ll_sb_info *sbi = ll_i2sbi(dir); @@ -819,26 +1054,42 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp, int lookup) LASSERT(lli->lli_opendir_pid == cfs_curproc_pid()); if (sai) { - if (unlikely(sai->sai_thread.t_flags & SVC_STOPPED && - list_empty(&sai->sai_entries))) + if (unlikely(sa_is_stopped(sai) && + list_empty(&sai->sai_entries_stated))) RETURN(-EBADFD); + /* + * skip the first dentry. + */ + if (unlikely((*dentryp)->d_name.len == + sai->sai_first->d_name.len && + !strncmp((*dentryp)->d_name.name, + sai->sai_first->d_name.name, + sai->sai_first->d_name.len))) + RETURN(-EEXIST); + if ((*dentryp)->d_name.name[0] == '.') { if (likely(sai->sai_ls_all || sai->sai_miss_hidden >= sai->sai_skip_hidden)) { - /* Hidden dentry is the first one, or statahead + /* + * Hidden dentry is the first one, or statahead * thread does not skip so many hidden dentries - * before "sai_ls_all" enabled as below. */ + * before "sai_ls_all" enabled as below. + */ } else { if (!sai->sai_ls_all) - /* It maybe because hidden dentry is not + /* + * It maybe because hidden dentry is not * the first one, "sai_ls_all" was not * set, then "ls -al" missed. Enable - * "sai_ls_all" for such case. */ + * "sai_ls_all" for such case. + */ sai->sai_ls_all = 1; - /* Such "getattr" has been skipped before - * "sai_ls_all" enabled as above. */ + /* + * Such "getattr" has been skipped before + * "sai_ls_all" enabled as above. + */ sai->sai_miss_hidden++; RETURN(-ENOENT); } @@ -848,10 +1099,11 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp, int lookup) sbi->ll_sa_cached++; } else { sbi->ll_sa_blocked++; - /* thread started already, avoid double-stat */ + /* + * thread started already, avoid double-stat. + */ l_wait_event(sai->sai_waitq, - ll_sai_entry_stated(sai) || - sai->sai_thread.t_flags & SVC_STOPPED, + ll_sai_entry_stated(sai) || sa_is_stopped(sai), &lwi); } @@ -867,16 +1119,22 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp, int lookup) RETURN(1); } } - /* do nothing for revalidate */ + /* + * do nothing for revalidate. + */ RETURN(0); } - /* I am the "lli_opendir_pid" owner, only me can set "lli_sai". */ + /* + * I am the "lli_opendir_pid" owner, only me can set "lli_sai". + */ LASSERT(lli->lli_sai == NULL); rc = is_first_dirent(dir, *dentryp); if (rc == LS_NONE_FIRST_DE) { - /* It is not "ls -{a}l" operation, no need statahead for it */ + /* + * 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; @@ -889,6 +1147,7 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp, int lookup) RETURN(-ENOMEM); sai->sai_inode = igrab(dir); + sai->sai_first = dget(*dentryp); sai->sai_ls_all = (rc == LS_FIRST_DOT_DE); sta.sta_parent = (*dentryp)->d_parent; @@ -905,29 +1164,34 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp, int lookup) } l_wait_event(sai->sai_thread.t_ctl_waitq, - sai->sai_thread.t_flags & (SVC_RUNNING | SVC_STOPPED), + sa_is_running(sai) || sa_is_stopped(sai), &lwi); - /* We don't stat-ahead for the first dirent since we are already in - * lookup, and -EEXIST also indicates that this is the first dirent. */ + /* + * We don't stat-ahead for the first dirent since we are already in + * lookup, and -EEXIST also indicates that this is the first dirent. + */ RETURN(-EEXIST); } -/* update hit/miss count */ -void ll_statahead_exit(struct dentry *dentry, int result) +/** + * update hit/miss count. + */ +int ll_statahead_exit(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_dentry_data *ldd = ll_d2d(dentry); + ENTRY; if (lli->lli_opendir_pid != cfs_curproc_pid()) - return; + RETURN(-EBADFD); if (lli->lli_sai) { struct ll_statahead_info *sai = lli->lli_sai; - if (result == 1) { + if (result >= 1) { sbi->ll_sa_hit++; sai->sai_hit++; sai->sai_consecutive_miss = 0; @@ -936,8 +1200,7 @@ void ll_statahead_exit(struct dentry *dentry, int result) sbi->ll_sa_miss++; sai->sai_miss++; sai->sai_consecutive_miss++; - if (sa_low_hit(sai) && - sai->sai_thread.t_flags & SVC_RUNNING) { + 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, " @@ -948,16 +1211,30 @@ void ll_statahead_exit(struct dentry *dentry, int result) sai->sai_sent, sai->sai_replied, cfs_curproc_pid()); spin_lock(&lli->lli_lock); - if (!(sai->sai_thread.t_flags & SVC_STOPPED)) + if (!sa_is_stopped(sai)) sai->sai_thread.t_flags = SVC_STOPPING; spin_unlock(&lli->lli_lock); } } - cfs_waitq_signal(&sai->sai_thread.t_ctl_waitq); - ll_sai_entry_put(sai); + if (!sa_is_stopped(sai)) + cfs_waitq_signal(&sai->sai_thread.t_ctl_waitq); + ll_sai_entry_fini(sai); + + if (unlikely(ldd == NULL)) { + ll_set_dd(dentry); + ldd = ll_d2d(dentry); + if (ldd != NULL && dentry->d_op == NULL) { + lock_dentry(dentry); + dentry->d_op = dentry->d_op ? : &ll_sai_d_ops; + unlock_dentry(dentry); + } + } if (likely(ldd != NULL)) ldd->lld_sa_generation = sai->sai_generation; + else + RETURN(-ENOMEM); } + RETURN(0); } -- 1.8.3.1