1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37#include <linux/fs.h>
38#include <linux/sched.h>
39#include <linux/mm.h>
40#include <linux/highmem.h>
41#include <linux/pagemap.h>
42
43#define DEBUG_SUBSYSTEM S_LLITE
44
45#include "../include/obd_support.h"
46#include "../include/lustre_lite.h"
47#include "../include/lustre_dlm.h"
48#include "llite_internal.h"
49
50#define SA_OMITTED_ENTRY_MAX 8ULL
51
52typedef enum {
53
54 SA_ENTRY_INIT = 0,
55 SA_ENTRY_SUCC = 1,
56 SA_ENTRY_INVA = 2,
57 SA_ENTRY_DEST = 3,
58} se_stat_t;
59
60struct ll_sa_entry {
61
62 struct list_head se_link;
63
64 struct list_head se_list;
65
66 struct list_head se_hash;
67
68 atomic_t se_refcount;
69
70 __u64 se_index;
71
72 __u64 se_handle;
73
74 se_stat_t se_stat;
75
76 int se_size;
77
78 struct md_enqueue_info *se_minfo;
79
80 struct ptlrpc_request *se_req;
81
82 struct inode *se_inode;
83
84 struct qstr se_qstr;
85};
86
87static unsigned int sai_generation;
88static DEFINE_SPINLOCK(sai_generation_lock);
89
90static inline int ll_sa_entry_unhashed(struct ll_sa_entry *entry)
91{
92 return list_empty(&entry->se_hash);
93}
94
95
96
97
98static inline int ll_sa_entry_stated(struct ll_sa_entry *entry)
99{
100 smp_rmb();
101 return (entry->se_stat != SA_ENTRY_INIT);
102}
103
104static inline int ll_sa_entry_hash(int val)
105{
106 return val & LL_SA_CACHE_MASK;
107}
108
109
110
111
112static inline void
113ll_sa_entry_enhash(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
114{
115 int i = ll_sa_entry_hash(entry->se_qstr.hash);
116
117 spin_lock(&sai->sai_cache_lock[i]);
118 list_add_tail(&entry->se_hash, &sai->sai_cache[i]);
119 spin_unlock(&sai->sai_cache_lock[i]);
120}
121
122
123
124
125static inline void
126ll_sa_entry_unhash(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
127{
128 int i = ll_sa_entry_hash(entry->se_qstr.hash);
129
130 spin_lock(&sai->sai_cache_lock[i]);
131 list_del_init(&entry->se_hash);
132 spin_unlock(&sai->sai_cache_lock[i]);
133}
134
135static inline int agl_should_run(struct ll_statahead_info *sai,
136 struct inode *inode)
137{
138 return (inode != NULL && S_ISREG(inode->i_mode) && sai->sai_agl_valid);
139}
140
141static inline struct ll_sa_entry *
142sa_first_received_entry(struct ll_statahead_info *sai)
143{
144 return list_entry(sai->sai_entries_received.next,
145 struct ll_sa_entry, se_list);
146}
147
148static inline struct ll_inode_info *
149agl_first_entry(struct ll_statahead_info *sai)
150{
151 return list_entry(sai->sai_entries_agl.next,
152 struct ll_inode_info, lli_agl_list);
153}
154
155static inline int sa_sent_full(struct ll_statahead_info *sai)
156{
157 return atomic_read(&sai->sai_cache_count) >= sai->sai_max;
158}
159
160static inline int sa_received_empty(struct ll_statahead_info *sai)
161{
162 return list_empty(&sai->sai_entries_received);
163}
164
165static inline int agl_list_empty(struct ll_statahead_info *sai)
166{
167 return list_empty(&sai->sai_entries_agl);
168}
169
170
171
172
173
174
175
176static inline int sa_low_hit(struct ll_statahead_info *sai)
177{
178 return ((sai->sai_hit > 7 && sai->sai_hit < 4 * sai->sai_miss) ||
179 (sai->sai_consecutive_miss > 8));
180}
181
182
183
184
185
186static inline int is_omitted_entry(struct ll_statahead_info *sai, __u64 index)
187{
188 return ((__u64)sai->sai_max + index + SA_OMITTED_ENTRY_MAX <
189 sai->sai_index);
190}
191
192
193
194
195static struct ll_sa_entry *
196ll_sa_entry_alloc(struct ll_statahead_info *sai, __u64 index,
197 const char *name, int len)
198{
199 struct ll_inode_info *lli;
200 struct ll_sa_entry *entry;
201 int entry_size;
202 char *dname;
203
204 entry_size = sizeof(struct ll_sa_entry) + (len & ~3) + 4;
205 entry = kzalloc(entry_size, GFP_NOFS);
206 if (unlikely(!entry))
207 return ERR_PTR(-ENOMEM);
208
209 CDEBUG(D_READA, "alloc sa entry %.*s(%p) index %llu\n",
210 len, name, entry, index);
211
212 entry->se_index = index;
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237 atomic_set(&entry->se_refcount, 2);
238 entry->se_stat = SA_ENTRY_INIT;
239 entry->se_size = entry_size;
240 dname = (char *)entry + sizeof(struct ll_sa_entry);
241 memcpy(dname, name, len);
242 dname[len] = 0;
243 entry->se_qstr.hash = full_name_hash(name, len);
244 entry->se_qstr.len = len;
245 entry->se_qstr.name = dname;
246
247 lli = ll_i2info(sai->sai_inode);
248 spin_lock(&lli->lli_sa_lock);
249 list_add_tail(&entry->se_link, &sai->sai_entries);
250 INIT_LIST_HEAD(&entry->se_list);
251 ll_sa_entry_enhash(sai, entry);
252 spin_unlock(&lli->lli_sa_lock);
253
254 atomic_inc(&sai->sai_cache_count);
255
256 return entry;
257}
258
259
260
261
262
263
264
265
266static struct ll_sa_entry *
267ll_sa_entry_get_byname(struct ll_statahead_info *sai, const struct qstr *qstr)
268{
269 struct ll_sa_entry *entry;
270 int i = ll_sa_entry_hash(qstr->hash);
271
272 list_for_each_entry(entry, &sai->sai_cache[i], se_hash) {
273 if (entry->se_qstr.hash == qstr->hash &&
274 entry->se_qstr.len == qstr->len &&
275 memcmp(entry->se_qstr.name, qstr->name, qstr->len) == 0)
276 return entry;
277 }
278 return NULL;
279}
280
281
282
283
284
285
286
287
288static struct ll_sa_entry *
289ll_sa_entry_get_byindex(struct ll_statahead_info *sai, __u64 index)
290{
291 struct ll_sa_entry *entry;
292
293 list_for_each_entry(entry, &sai->sai_entries, se_link) {
294 if (entry->se_index == index) {
295 LASSERT(atomic_read(&entry->se_refcount) > 0);
296 atomic_inc(&entry->se_refcount);
297 return entry;
298 }
299 if (entry->se_index > index)
300 break;
301 }
302 return NULL;
303}
304
305static void ll_sa_entry_cleanup(struct ll_statahead_info *sai,
306 struct ll_sa_entry *entry)
307{
308 struct md_enqueue_info *minfo = entry->se_minfo;
309 struct ptlrpc_request *req = entry->se_req;
310
311 if (minfo) {
312 entry->se_minfo = NULL;
313 ll_intent_release(&minfo->mi_it);
314 iput(minfo->mi_dir);
315 kfree(minfo);
316 }
317
318 if (req) {
319 entry->se_req = NULL;
320 ptlrpc_req_finished(req);
321 }
322}
323
324static void ll_sa_entry_put(struct ll_statahead_info *sai,
325 struct ll_sa_entry *entry)
326{
327 if (atomic_dec_and_test(&entry->se_refcount)) {
328 CDEBUG(D_READA, "free sa entry %.*s(%p) index %llu\n",
329 entry->se_qstr.len, entry->se_qstr.name, entry,
330 entry->se_index);
331
332 LASSERT(list_empty(&entry->se_link));
333 LASSERT(list_empty(&entry->se_list));
334 LASSERT(ll_sa_entry_unhashed(entry));
335
336 ll_sa_entry_cleanup(sai, entry);
337 iput(entry->se_inode);
338
339 kfree(entry);
340 atomic_dec(&sai->sai_cache_count);
341 }
342}
343
344static inline void
345do_sa_entry_fini(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
346{
347 struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
348
349 LASSERT(!ll_sa_entry_unhashed(entry));
350 LASSERT(!list_empty(&entry->se_link));
351
352 ll_sa_entry_unhash(sai, entry);
353
354 spin_lock(&lli->lli_sa_lock);
355 entry->se_stat = SA_ENTRY_DEST;
356 list_del_init(&entry->se_link);
357 if (likely(!list_empty(&entry->se_list)))
358 list_del_init(&entry->se_list);
359 spin_unlock(&lli->lli_sa_lock);
360
361 ll_sa_entry_put(sai, entry);
362}
363
364
365
366
367static void
368ll_sa_entry_fini(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
369{
370 struct ll_sa_entry *pos, *next;
371
372 if (entry)
373 do_sa_entry_fini(sai, entry);
374
375
376 list_for_each_entry_safe(pos, next, &sai->sai_entries, se_link) {
377 if (!is_omitted_entry(sai, pos->se_index))
378 break;
379 do_sa_entry_fini(sai, pos);
380 }
381}
382
383
384
385
386static void
387do_sa_entry_to_stated(struct ll_statahead_info *sai,
388 struct ll_sa_entry *entry, se_stat_t stat)
389{
390 struct ll_sa_entry *se;
391 struct list_head *pos = &sai->sai_entries_stated;
392
393 if (!list_empty(&entry->se_list))
394 list_del_init(&entry->se_list);
395
396 list_for_each_entry_reverse(se, &sai->sai_entries_stated, se_list) {
397 if (se->se_index < entry->se_index) {
398 pos = &se->se_list;
399 break;
400 }
401 }
402
403 list_add(&entry->se_list, pos);
404 entry->se_stat = stat;
405}
406
407
408
409
410
411
412static int
413ll_sa_entry_to_stated(struct ll_statahead_info *sai,
414 struct ll_sa_entry *entry, se_stat_t stat)
415{
416 struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
417 int ret = 1;
418
419 ll_sa_entry_cleanup(sai, entry);
420
421 spin_lock(&lli->lli_sa_lock);
422 if (likely(entry->se_stat != SA_ENTRY_DEST)) {
423 do_sa_entry_to_stated(sai, entry, stat);
424 ret = 0;
425 }
426 spin_unlock(&lli->lli_sa_lock);
427
428 return ret;
429}
430
431
432
433
434static void ll_agl_add(struct ll_statahead_info *sai,
435 struct inode *inode, int index)
436{
437 struct ll_inode_info *child = ll_i2info(inode);
438 struct ll_inode_info *parent = ll_i2info(sai->sai_inode);
439 int added = 0;
440
441 spin_lock(&child->lli_agl_lock);
442 if (child->lli_agl_index == 0) {
443 child->lli_agl_index = index;
444 spin_unlock(&child->lli_agl_lock);
445
446 LASSERT(list_empty(&child->lli_agl_list));
447
448 igrab(inode);
449 spin_lock(&parent->lli_agl_lock);
450 if (agl_list_empty(sai))
451 added = 1;
452 list_add_tail(&child->lli_agl_list, &sai->sai_entries_agl);
453 spin_unlock(&parent->lli_agl_lock);
454 } else {
455 spin_unlock(&child->lli_agl_lock);
456 }
457
458 if (added > 0)
459 wake_up(&sai->sai_agl_thread.t_ctl_waitq);
460}
461
462static struct ll_statahead_info *ll_sai_alloc(void)
463{
464 struct ll_statahead_info *sai;
465 int i;
466
467 sai = kzalloc(sizeof(*sai), GFP_NOFS);
468 if (!sai)
469 return NULL;
470
471 atomic_set(&sai->sai_refcount, 1);
472
473 spin_lock(&sai_generation_lock);
474 sai->sai_generation = ++sai_generation;
475 if (unlikely(sai_generation == 0))
476 sai->sai_generation = ++sai_generation;
477 spin_unlock(&sai_generation_lock);
478
479 sai->sai_max = LL_SA_RPC_MIN;
480 sai->sai_index = 1;
481 init_waitqueue_head(&sai->sai_waitq);
482 init_waitqueue_head(&sai->sai_thread.t_ctl_waitq);
483 init_waitqueue_head(&sai->sai_agl_thread.t_ctl_waitq);
484
485 INIT_LIST_HEAD(&sai->sai_entries);
486 INIT_LIST_HEAD(&sai->sai_entries_received);
487 INIT_LIST_HEAD(&sai->sai_entries_stated);
488 INIT_LIST_HEAD(&sai->sai_entries_agl);
489
490 for (i = 0; i < LL_SA_CACHE_SIZE; i++) {
491 INIT_LIST_HEAD(&sai->sai_cache[i]);
492 spin_lock_init(&sai->sai_cache_lock[i]);
493 }
494 atomic_set(&sai->sai_cache_count, 0);
495
496 return sai;
497}
498
499static inline struct ll_statahead_info *
500ll_sai_get(struct ll_statahead_info *sai)
501{
502 atomic_inc(&sai->sai_refcount);
503 return sai;
504}
505
506static void ll_sai_put(struct ll_statahead_info *sai)
507{
508 struct inode *inode = sai->sai_inode;
509 struct ll_inode_info *lli = ll_i2info(inode);
510
511 if (atomic_dec_and_lock(&sai->sai_refcount, &lli->lli_sa_lock)) {
512 struct ll_sa_entry *entry, *next;
513
514 if (unlikely(atomic_read(&sai->sai_refcount) > 0)) {
515
516
517 spin_unlock(&lli->lli_sa_lock);
518 return;
519 }
520
521 LASSERT(lli->lli_opendir_key == NULL);
522 LASSERT(thread_is_stopped(&sai->sai_thread));
523 LASSERT(thread_is_stopped(&sai->sai_agl_thread));
524
525 lli->lli_sai = NULL;
526 lli->lli_opendir_pid = 0;
527 spin_unlock(&lli->lli_sa_lock);
528
529 if (sai->sai_sent > sai->sai_replied)
530 CDEBUG(D_READA, "statahead for dir "DFID
531 " does not finish: [sent:%llu] [replied:%llu]\n",
532 PFID(&lli->lli_fid),
533 sai->sai_sent, sai->sai_replied);
534
535 list_for_each_entry_safe(entry, next,
536 &sai->sai_entries, se_link)
537 do_sa_entry_fini(sai, entry);
538
539 LASSERT(list_empty(&sai->sai_entries));
540 LASSERT(sa_received_empty(sai));
541 LASSERT(list_empty(&sai->sai_entries_stated));
542
543 LASSERT(atomic_read(&sai->sai_cache_count) == 0);
544 LASSERT(agl_list_empty(sai));
545
546 iput(inode);
547 kfree(sai);
548 }
549}
550
551
552static void ll_agl_trigger(struct inode *inode, struct ll_statahead_info *sai)
553{
554 struct ll_inode_info *lli = ll_i2info(inode);
555 __u64 index = lli->lli_agl_index;
556 int rc;
557
558 LASSERT(list_empty(&lli->lli_agl_list));
559
560
561 if (is_omitted_entry(sai, index + 1)) {
562 lli->lli_agl_index = 0;
563 iput(inode);
564 return;
565 }
566
567
568 rc = down_write_trylock(&lli->lli_glimpse_sem);
569 if (rc == 0) {
570 lli->lli_agl_index = 0;
571 iput(inode);
572 return;
573 }
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588 if (lli->lli_glimpse_time != 0 &&
589 time_before(cfs_time_shift(-1), lli->lli_glimpse_time)) {
590 up_write(&lli->lli_glimpse_sem);
591 lli->lli_agl_index = 0;
592 iput(inode);
593 return;
594 }
595
596 CDEBUG(D_READA, "Handling (init) async glimpse: inode = "
597 DFID", idx = %llu\n", PFID(&lli->lli_fid), index);
598
599 cl_agl(inode);
600 lli->lli_agl_index = 0;
601 lli->lli_glimpse_time = cfs_time_current();
602 up_write(&lli->lli_glimpse_sem);
603
604 CDEBUG(D_READA, "Handled (init) async glimpse: inode= "
605 DFID", idx = %llu, rc = %d\n",
606 PFID(&lli->lli_fid), index, rc);
607
608 iput(inode);
609}
610
611static void ll_post_statahead(struct ll_statahead_info *sai)
612{
613 struct inode *dir = sai->sai_inode;
614 struct inode *child;
615 struct ll_inode_info *lli = ll_i2info(dir);
616 struct ll_sa_entry *entry;
617 struct md_enqueue_info *minfo;
618 struct lookup_intent *it;
619 struct ptlrpc_request *req;
620 struct mdt_body *body;
621 int rc = 0;
622
623 spin_lock(&lli->lli_sa_lock);
624 if (unlikely(sa_received_empty(sai))) {
625 spin_unlock(&lli->lli_sa_lock);
626 return;
627 }
628 entry = sa_first_received_entry(sai);
629 atomic_inc(&entry->se_refcount);
630 list_del_init(&entry->se_list);
631 spin_unlock(&lli->lli_sa_lock);
632
633 LASSERT(entry->se_handle != 0);
634
635 minfo = entry->se_minfo;
636 it = &minfo->mi_it;
637 req = entry->se_req;
638 body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
639 if (body == NULL) {
640 rc = -EFAULT;
641 goto out;
642 }
643
644 child = entry->se_inode;
645 if (child == NULL) {
646
647
648
649 LASSERT(fid_is_zero(&minfo->mi_data.op_fid2));
650
651
652
653 if (body->valid & OBD_MD_MDS) {
654 rc = -EAGAIN;
655 goto out;
656 }
657 } else {
658
659
660
661
662 if (unlikely(!lu_fid_eq(&minfo->mi_data.op_fid2, &body->fid1))){
663 entry->se_inode = NULL;
664 iput(child);
665 child = NULL;
666 }
667 }
668
669 it->d.lustre.it_lock_handle = entry->se_handle;
670 rc = md_revalidate_lock(ll_i2mdexp(dir), it, ll_inode2fid(dir), NULL);
671 if (rc != 1) {
672 rc = -EAGAIN;
673 goto out;
674 }
675
676 rc = ll_prep_inode(&child, req, dir->i_sb, it);
677 if (rc)
678 goto out;
679
680 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
681 child, child->i_ino, child->i_generation);
682 ll_set_lock_data(ll_i2sbi(dir)->ll_md_exp, child, it, NULL);
683
684 entry->se_inode = child;
685
686 if (agl_should_run(sai, child))
687 ll_agl_add(sai, child, entry->se_index);
688
689out:
690
691
692
693
694 rc = ll_sa_entry_to_stated(sai, entry,
695 rc < 0 ? SA_ENTRY_INVA : SA_ENTRY_SUCC);
696 if (rc == 0 && entry->se_index == sai->sai_index_wait)
697 wake_up(&sai->sai_waitq);
698 ll_sa_entry_put(sai, entry);
699}
700
701static int ll_statahead_interpret(struct ptlrpc_request *req,
702 struct md_enqueue_info *minfo, int rc)
703{
704 struct lookup_intent *it = &minfo->mi_it;
705 struct inode *dir = minfo->mi_dir;
706 struct ll_inode_info *lli = ll_i2info(dir);
707 struct ll_statahead_info *sai = NULL;
708 struct ll_sa_entry *entry;
709 __u64 handle = 0;
710 int wakeup;
711
712 if (it_disposition(it, DISP_LOOKUP_NEG))
713 rc = -ENOENT;
714
715 if (rc == 0) {
716
717
718
719
720 handle = it->d.lustre.it_lock_handle;
721 ll_intent_drop_lock(it);
722 }
723
724 spin_lock(&lli->lli_sa_lock);
725
726 if (unlikely(lli->lli_sai == NULL ||
727 lli->lli_sai->sai_generation != minfo->mi_generation)) {
728 spin_unlock(&lli->lli_sa_lock);
729 rc = -ESTALE;
730 goto out;
731 } else {
732 sai = ll_sai_get(lli->lli_sai);
733 if (unlikely(!thread_is_running(&sai->sai_thread))) {
734 sai->sai_replied++;
735 spin_unlock(&lli->lli_sa_lock);
736 rc = -EBADFD;
737 goto out;
738 }
739
740 entry = ll_sa_entry_get_byindex(sai, minfo->mi_cbdata);
741 if (entry == NULL) {
742 sai->sai_replied++;
743 spin_unlock(&lli->lli_sa_lock);
744 rc = -EIDRM;
745 goto out;
746 }
747
748 if (rc != 0) {
749 do_sa_entry_to_stated(sai, entry, SA_ENTRY_INVA);
750 wakeup = (entry->se_index == sai->sai_index_wait);
751 } else {
752 entry->se_minfo = minfo;
753 entry->se_req = ptlrpc_request_addref(req);
754
755
756
757
758 entry->se_handle = handle;
759 wakeup = sa_received_empty(sai);
760 list_add_tail(&entry->se_list,
761 &sai->sai_entries_received);
762 }
763 sai->sai_replied++;
764 spin_unlock(&lli->lli_sa_lock);
765
766 ll_sa_entry_put(sai, entry);
767 if (wakeup)
768 wake_up(&sai->sai_thread.t_ctl_waitq);
769 }
770
771out:
772 if (rc != 0) {
773 ll_intent_release(it);
774 iput(dir);
775 kfree(minfo);
776 }
777 if (sai != NULL)
778 ll_sai_put(sai);
779 return rc;
780}
781
782static void sa_args_fini(struct md_enqueue_info *minfo,
783 struct ldlm_enqueue_info *einfo)
784{
785 LASSERT(minfo && einfo);
786 iput(minfo->mi_dir);
787 capa_put(minfo->mi_data.op_capa1);
788 capa_put(minfo->mi_data.op_capa2);
789 kfree(minfo);
790 kfree(einfo);
791}
792
793
794
795
796
797
798
799
800
801
802static int sa_args_init(struct inode *dir, struct inode *child,
803 struct ll_sa_entry *entry, struct md_enqueue_info **pmi,
804 struct ldlm_enqueue_info **pei,
805 struct obd_capa **pcapa)
806{
807 struct qstr *qstr = &entry->se_qstr;
808 struct ll_inode_info *lli = ll_i2info(dir);
809 struct md_enqueue_info *minfo;
810 struct ldlm_enqueue_info *einfo;
811 struct md_op_data *op_data;
812
813 einfo = kzalloc(sizeof(*einfo), GFP_NOFS);
814 if (!einfo)
815 return -ENOMEM;
816
817 minfo = kzalloc(sizeof(*minfo), GFP_NOFS);
818 if (!minfo) {
819 kfree(einfo);
820 return -ENOMEM;
821 }
822
823 op_data = ll_prep_md_op_data(&minfo->mi_data, dir, child, qstr->name,
824 qstr->len, 0, LUSTRE_OPC_ANY, NULL);
825 if (IS_ERR(op_data)) {
826 kfree(einfo);
827 kfree(minfo);
828 return PTR_ERR(op_data);
829 }
830
831 minfo->mi_it.it_op = IT_GETATTR;
832 minfo->mi_dir = igrab(dir);
833 minfo->mi_cb = ll_statahead_interpret;
834 minfo->mi_generation = lli->lli_sai->sai_generation;
835 minfo->mi_cbdata = entry->se_index;
836
837 einfo->ei_type = LDLM_IBITS;
838 einfo->ei_mode = it_to_lock_mode(&minfo->mi_it);
839 einfo->ei_cb_bl = ll_md_blocking_ast;
840 einfo->ei_cb_cp = ldlm_completion_ast;
841 einfo->ei_cb_gl = NULL;
842 einfo->ei_cbdata = NULL;
843
844 *pmi = minfo;
845 *pei = einfo;
846 pcapa[0] = op_data->op_capa1;
847 pcapa[1] = op_data->op_capa2;
848
849 return 0;
850}
851
852static int do_sa_lookup(struct inode *dir, struct ll_sa_entry *entry)
853{
854 struct md_enqueue_info *minfo;
855 struct ldlm_enqueue_info *einfo;
856 struct obd_capa *capas[2];
857 int rc;
858
859 rc = sa_args_init(dir, NULL, entry, &minfo, &einfo, capas);
860 if (rc)
861 return rc;
862
863 rc = md_intent_getattr_async(ll_i2mdexp(dir), minfo, einfo);
864 if (!rc) {
865 capa_put(capas[0]);
866 capa_put(capas[1]);
867 } else {
868 sa_args_fini(minfo, einfo);
869 }
870
871 return rc;
872}
873
874
875
876
877
878
879
880static int do_sa_revalidate(struct inode *dir, struct ll_sa_entry *entry,
881 struct dentry *dentry)
882{
883 struct inode *inode = d_inode(dentry);
884 struct lookup_intent it = { .it_op = IT_GETATTR,
885 .d.lustre.it_lock_handle = 0 };
886 struct md_enqueue_info *minfo;
887 struct ldlm_enqueue_info *einfo;
888 struct obd_capa *capas[2];
889 int rc;
890
891 if (unlikely(inode == NULL))
892 return 1;
893
894 if (d_mountpoint(dentry))
895 return 1;
896
897 entry->se_inode = igrab(inode);
898 rc = md_revalidate_lock(ll_i2mdexp(dir), &it, ll_inode2fid(inode),
899 NULL);
900 if (rc == 1) {
901 entry->se_handle = it.d.lustre.it_lock_handle;
902 ll_intent_release(&it);
903 return 1;
904 }
905
906 rc = sa_args_init(dir, inode, entry, &minfo, &einfo, capas);
907 if (rc) {
908 entry->se_inode = NULL;
909 iput(inode);
910 return rc;
911 }
912
913 rc = md_intent_getattr_async(ll_i2mdexp(dir), minfo, einfo);
914 if (!rc) {
915 capa_put(capas[0]);
916 capa_put(capas[1]);
917 } else {
918 entry->se_inode = NULL;
919 iput(inode);
920 sa_args_fini(minfo, einfo);
921 }
922
923 return rc;
924}
925
926static void ll_statahead_one(struct dentry *parent, const char *entry_name,
927 int entry_name_len)
928{
929 struct inode *dir = d_inode(parent);
930 struct ll_inode_info *lli = ll_i2info(dir);
931 struct ll_statahead_info *sai = lli->lli_sai;
932 struct dentry *dentry = NULL;
933 struct ll_sa_entry *entry;
934 int rc;
935 int rc1;
936
937 entry = ll_sa_entry_alloc(sai, sai->sai_index, entry_name,
938 entry_name_len);
939 if (IS_ERR(entry))
940 return;
941
942 dentry = d_lookup(parent, &entry->se_qstr);
943 if (!dentry) {
944 rc = do_sa_lookup(dir, entry);
945 } else {
946 rc = do_sa_revalidate(dir, entry, dentry);
947 if (rc == 1 && agl_should_run(sai, d_inode(dentry)))
948 ll_agl_add(sai, d_inode(dentry), entry->se_index);
949 }
950
951 if (dentry != NULL)
952 dput(dentry);
953
954 if (rc) {
955 rc1 = ll_sa_entry_to_stated(sai, entry,
956 rc < 0 ? SA_ENTRY_INVA : SA_ENTRY_SUCC);
957 if (rc1 == 0 && entry->se_index == sai->sai_index_wait)
958 wake_up(&sai->sai_waitq);
959 } else {
960 sai->sai_sent++;
961 }
962
963 sai->sai_index++;
964
965 ll_sa_entry_put(sai, entry);
966}
967
968static int ll_agl_thread(void *arg)
969{
970 struct dentry *parent = (struct dentry *)arg;
971 struct inode *dir = d_inode(parent);
972 struct ll_inode_info *plli = ll_i2info(dir);
973 struct ll_inode_info *clli;
974 struct ll_sb_info *sbi = ll_i2sbi(dir);
975 struct ll_statahead_info *sai = ll_sai_get(plli->lli_sai);
976 struct ptlrpc_thread *thread = &sai->sai_agl_thread;
977 struct l_wait_info lwi = { 0 };
978
979 thread->t_pid = current_pid();
980 CDEBUG(D_READA, "agl thread started: sai %p, parent %pd\n",
981 sai, parent);
982
983 atomic_inc(&sbi->ll_agl_total);
984 spin_lock(&plli->lli_agl_lock);
985 sai->sai_agl_valid = 1;
986 if (thread_is_init(thread))
987
988
989
990 thread_set_flags(thread, SVC_RUNNING);
991 spin_unlock(&plli->lli_agl_lock);
992 wake_up(&thread->t_ctl_waitq);
993
994 while (1) {
995 l_wait_event(thread->t_ctl_waitq,
996 !agl_list_empty(sai) ||
997 !thread_is_running(thread),
998 &lwi);
999
1000 if (!thread_is_running(thread))
1001 break;
1002
1003 spin_lock(&plli->lli_agl_lock);
1004
1005
1006 if (!agl_list_empty(sai)) {
1007 clli = agl_first_entry(sai);
1008 list_del_init(&clli->lli_agl_list);
1009 spin_unlock(&plli->lli_agl_lock);
1010 ll_agl_trigger(&clli->lli_vfs_inode, sai);
1011 } else {
1012 spin_unlock(&plli->lli_agl_lock);
1013 }
1014 }
1015
1016 spin_lock(&plli->lli_agl_lock);
1017 sai->sai_agl_valid = 0;
1018 while (!agl_list_empty(sai)) {
1019 clli = agl_first_entry(sai);
1020 list_del_init(&clli->lli_agl_list);
1021 spin_unlock(&plli->lli_agl_lock);
1022 clli->lli_agl_index = 0;
1023 iput(&clli->lli_vfs_inode);
1024 spin_lock(&plli->lli_agl_lock);
1025 }
1026 thread_set_flags(thread, SVC_STOPPED);
1027 spin_unlock(&plli->lli_agl_lock);
1028 wake_up(&thread->t_ctl_waitq);
1029 ll_sai_put(sai);
1030 CDEBUG(D_READA, "agl thread stopped: sai %p, parent %pd\n",
1031 sai, parent);
1032 return 0;
1033}
1034
1035static void ll_start_agl(struct dentry *parent, struct ll_statahead_info *sai)
1036{
1037 struct ptlrpc_thread *thread = &sai->sai_agl_thread;
1038 struct l_wait_info lwi = { 0 };
1039 struct ll_inode_info *plli;
1040 struct task_struct *task;
1041
1042 CDEBUG(D_READA, "start agl thread: sai %p, parent %pd\n",
1043 sai, parent);
1044
1045 plli = ll_i2info(d_inode(parent));
1046 task = kthread_run(ll_agl_thread, parent,
1047 "ll_agl_%u", plli->lli_opendir_pid);
1048 if (IS_ERR(task)) {
1049 CERROR("can't start ll_agl thread, rc: %ld\n", PTR_ERR(task));
1050 thread_set_flags(thread, SVC_STOPPED);
1051 return;
1052 }
1053
1054 l_wait_event(thread->t_ctl_waitq,
1055 thread_is_running(thread) || thread_is_stopped(thread),
1056 &lwi);
1057}
1058
1059static int ll_statahead_thread(void *arg)
1060{
1061 struct dentry *parent = (struct dentry *)arg;
1062 struct inode *dir = d_inode(parent);
1063 struct ll_inode_info *plli = ll_i2info(dir);
1064 struct ll_inode_info *clli;
1065 struct ll_sb_info *sbi = ll_i2sbi(dir);
1066 struct ll_statahead_info *sai = ll_sai_get(plli->lli_sai);
1067 struct ptlrpc_thread *thread = &sai->sai_thread;
1068 struct ptlrpc_thread *agl_thread = &sai->sai_agl_thread;
1069 struct page *page;
1070 __u64 pos = 0;
1071 int first = 0;
1072 int rc = 0;
1073 struct ll_dir_chain chain;
1074 struct l_wait_info lwi = { 0 };
1075
1076 thread->t_pid = current_pid();
1077 CDEBUG(D_READA, "statahead thread starting: sai %p, parent %pd\n",
1078 sai, parent);
1079
1080 if (sbi->ll_flags & LL_SBI_AGL_ENABLED)
1081 ll_start_agl(parent, sai);
1082
1083 atomic_inc(&sbi->ll_sa_total);
1084 spin_lock(&plli->lli_sa_lock);
1085 if (thread_is_init(thread))
1086
1087
1088
1089 thread_set_flags(thread, SVC_RUNNING);
1090 spin_unlock(&plli->lli_sa_lock);
1091 wake_up(&thread->t_ctl_waitq);
1092
1093 ll_dir_chain_init(&chain);
1094 page = ll_get_dir_page(dir, pos, &chain);
1095
1096 while (1) {
1097 struct lu_dirpage *dp;
1098 struct lu_dirent *ent;
1099
1100 if (IS_ERR(page)) {
1101 rc = PTR_ERR(page);
1102 CDEBUG(D_READA, "error reading dir "DFID" at %llu/%llu: [rc %d] [parent %u]\n",
1103 PFID(ll_inode2fid(dir)), pos, sai->sai_index,
1104 rc, plli->lli_opendir_pid);
1105 goto out;
1106 }
1107
1108 dp = page_address(page);
1109 for (ent = lu_dirent_start(dp); ent != NULL;
1110 ent = lu_dirent_next(ent)) {
1111 __u64 hash;
1112 int namelen;
1113 char *name;
1114
1115 hash = le64_to_cpu(ent->lde_hash);
1116 if (unlikely(hash < pos))
1117
1118
1119
1120 continue;
1121
1122 namelen = le16_to_cpu(ent->lde_namelen);
1123 if (unlikely(namelen == 0))
1124
1125
1126
1127 continue;
1128
1129 name = ent->lde_name;
1130 if (name[0] == '.') {
1131 if (namelen == 1) {
1132
1133
1134
1135 continue;
1136 } else if (name[1] == '.' && namelen == 2) {
1137
1138
1139
1140 continue;
1141 } else if (!sai->sai_ls_all) {
1142
1143
1144
1145 sai->sai_skip_hidden++;
1146 continue;
1147 }
1148 }
1149
1150
1151
1152
1153 if (unlikely(++first == 1))
1154 continue;
1155
1156keep_it:
1157 l_wait_event(thread->t_ctl_waitq,
1158 !sa_sent_full(sai) ||
1159 !sa_received_empty(sai) ||
1160 !agl_list_empty(sai) ||
1161 !thread_is_running(thread),
1162 &lwi);
1163
1164interpret_it:
1165 while (!sa_received_empty(sai))
1166 ll_post_statahead(sai);
1167
1168 if (unlikely(!thread_is_running(thread))) {
1169 ll_release_page(page, 0);
1170 rc = 0;
1171 goto out;
1172 }
1173
1174
1175
1176
1177 if (sa_sent_full(sai)) {
1178 spin_lock(&plli->lli_agl_lock);
1179 while (!agl_list_empty(sai)) {
1180 clli = agl_first_entry(sai);
1181 list_del_init(&clli->lli_agl_list);
1182 spin_unlock(&plli->lli_agl_lock);
1183 ll_agl_trigger(&clli->lli_vfs_inode,
1184 sai);
1185
1186 if (!sa_received_empty(sai))
1187 goto interpret_it;
1188
1189 if (unlikely(
1190 !thread_is_running(thread))) {
1191 ll_release_page(page, 0);
1192 rc = 0;
1193 goto out;
1194 }
1195
1196 if (!sa_sent_full(sai))
1197 goto do_it;
1198
1199 spin_lock(&plli->lli_agl_lock);
1200 }
1201 spin_unlock(&plli->lli_agl_lock);
1202
1203 goto keep_it;
1204 }
1205
1206do_it:
1207 ll_statahead_one(parent, name, namelen);
1208 }
1209 pos = le64_to_cpu(dp->ldp_hash_end);
1210 if (pos == MDS_DIR_END_OFF) {
1211
1212
1213
1214 ll_release_page(page, 0);
1215 while (1) {
1216 l_wait_event(thread->t_ctl_waitq,
1217 !sa_received_empty(sai) ||
1218 sai->sai_sent == sai->sai_replied||
1219 !thread_is_running(thread),
1220 &lwi);
1221
1222 while (!sa_received_empty(sai))
1223 ll_post_statahead(sai);
1224
1225 if (unlikely(!thread_is_running(thread))) {
1226 rc = 0;
1227 goto out;
1228 }
1229
1230 if (sai->sai_sent == sai->sai_replied &&
1231 sa_received_empty(sai))
1232 break;
1233 }
1234
1235 spin_lock(&plli->lli_agl_lock);
1236 while (!agl_list_empty(sai) &&
1237 thread_is_running(thread)) {
1238 clli = agl_first_entry(sai);
1239 list_del_init(&clli->lli_agl_list);
1240 spin_unlock(&plli->lli_agl_lock);
1241 ll_agl_trigger(&clli->lli_vfs_inode, sai);
1242 spin_lock(&plli->lli_agl_lock);
1243 }
1244 spin_unlock(&plli->lli_agl_lock);
1245
1246 rc = 0;
1247 goto out;
1248 } else if (1) {
1249
1250
1251
1252
1253 ll_release_page(page, le32_to_cpu(dp->ldp_flags) &
1254 LDF_COLLIDE);
1255 page = ll_get_dir_page(dir, pos, &chain);
1256 } else {
1257 LASSERT(le32_to_cpu(dp->ldp_flags) & LDF_COLLIDE);
1258 ll_release_page(page, 1);
1259
1260
1261
1262 }
1263 }
1264
1265out:
1266 if (sai->sai_agl_valid) {
1267 spin_lock(&plli->lli_agl_lock);
1268 thread_set_flags(agl_thread, SVC_STOPPING);
1269 spin_unlock(&plli->lli_agl_lock);
1270 wake_up(&agl_thread->t_ctl_waitq);
1271
1272 CDEBUG(D_READA, "stop agl thread: sai %p pid %u\n",
1273 sai, (unsigned int)agl_thread->t_pid);
1274 l_wait_event(agl_thread->t_ctl_waitq,
1275 thread_is_stopped(agl_thread),
1276 &lwi);
1277 } else {
1278
1279 thread_set_flags(&sai->sai_agl_thread, SVC_STOPPED);
1280 }
1281 ll_dir_chain_fini(&chain);
1282 spin_lock(&plli->lli_sa_lock);
1283 if (!sa_received_empty(sai)) {
1284 thread_set_flags(thread, SVC_STOPPING);
1285 spin_unlock(&plli->lli_sa_lock);
1286
1287
1288 while (!sa_received_empty(sai))
1289 ll_post_statahead(sai);
1290
1291 spin_lock(&plli->lli_sa_lock);
1292 }
1293 thread_set_flags(thread, SVC_STOPPED);
1294 spin_unlock(&plli->lli_sa_lock);
1295 wake_up(&sai->sai_waitq);
1296 wake_up(&thread->t_ctl_waitq);
1297 ll_sai_put(sai);
1298 dput(parent);
1299 CDEBUG(D_READA, "statahead thread stopped: sai %p, parent %pd\n",
1300 sai, parent);
1301 return rc;
1302}
1303
1304
1305
1306
1307void ll_stop_statahead(struct inode *dir, void *key)
1308{
1309 struct ll_inode_info *lli = ll_i2info(dir);
1310
1311 if (unlikely(key == NULL))
1312 return;
1313
1314 spin_lock(&lli->lli_sa_lock);
1315 if (lli->lli_opendir_key != key || lli->lli_opendir_pid == 0) {
1316 spin_unlock(&lli->lli_sa_lock);
1317 return;
1318 }
1319
1320 lli->lli_opendir_key = NULL;
1321
1322 if (lli->lli_sai) {
1323 struct l_wait_info lwi = { 0 };
1324 struct ptlrpc_thread *thread = &lli->lli_sai->sai_thread;
1325
1326 if (!thread_is_stopped(thread)) {
1327 thread_set_flags(thread, SVC_STOPPING);
1328 spin_unlock(&lli->lli_sa_lock);
1329 wake_up(&thread->t_ctl_waitq);
1330
1331 CDEBUG(D_READA, "stop statahead thread: sai %p pid %u\n",
1332 lli->lli_sai, (unsigned int)thread->t_pid);
1333 l_wait_event(thread->t_ctl_waitq,
1334 thread_is_stopped(thread),
1335 &lwi);
1336 } else {
1337 spin_unlock(&lli->lli_sa_lock);
1338 }
1339
1340
1341
1342
1343
1344
1345 ll_sai_put(lli->lli_sai);
1346 } else {
1347 lli->lli_opendir_pid = 0;
1348 spin_unlock(&lli->lli_sa_lock);
1349 }
1350}
1351
1352enum {
1353
1354
1355
1356 LS_NONE_FIRST_DE = 0,
1357
1358
1359
1360 LS_FIRST_DE,
1361
1362
1363
1364 LS_FIRST_DOT_DE
1365};
1366
1367static int is_first_dirent(struct inode *dir, struct dentry *dentry)
1368{
1369 struct ll_dir_chain chain;
1370 struct qstr *target = &dentry->d_name;
1371 struct page *page;
1372 __u64 pos = 0;
1373 int dot_de;
1374 int rc = LS_NONE_FIRST_DE;
1375
1376 ll_dir_chain_init(&chain);
1377 page = ll_get_dir_page(dir, pos, &chain);
1378
1379 while (1) {
1380 struct lu_dirpage *dp;
1381 struct lu_dirent *ent;
1382
1383 if (IS_ERR(page)) {
1384 struct ll_inode_info *lli = ll_i2info(dir);
1385
1386 rc = PTR_ERR(page);
1387 CERROR("error reading dir "DFID" at %llu: [rc %d] [parent %u]\n",
1388 PFID(ll_inode2fid(dir)), pos,
1389 rc, lli->lli_opendir_pid);
1390 break;
1391 }
1392
1393 dp = page_address(page);
1394 for (ent = lu_dirent_start(dp); ent != NULL;
1395 ent = lu_dirent_next(ent)) {
1396 __u64 hash;
1397 int namelen;
1398 char *name;
1399
1400 hash = le64_to_cpu(ent->lde_hash);
1401
1402
1403 if (unlikely(hash < pos))
1404 continue;
1405
1406 namelen = le16_to_cpu(ent->lde_namelen);
1407 if (unlikely(namelen == 0))
1408
1409
1410
1411 continue;
1412
1413 name = ent->lde_name;
1414 if (name[0] == '.') {
1415 if (namelen == 1)
1416
1417
1418
1419 continue;
1420 else if (name[1] == '.' && namelen == 2)
1421
1422
1423
1424 continue;
1425 else
1426 dot_de = 1;
1427 } else {
1428 dot_de = 0;
1429 }
1430
1431 if (dot_de && target->name[0] != '.') {
1432 CDEBUG(D_READA, "%.*s skip hidden file %.*s\n",
1433 target->len, target->name,
1434 namelen, name);
1435 continue;
1436 }
1437
1438 if (target->len != namelen ||
1439 memcmp(target->name, name, namelen) != 0)
1440 rc = LS_NONE_FIRST_DE;
1441 else if (!dot_de)
1442 rc = LS_FIRST_DE;
1443 else
1444 rc = LS_FIRST_DOT_DE;
1445
1446 ll_release_page(page, 0);
1447 goto out;
1448 }
1449 pos = le64_to_cpu(dp->ldp_hash_end);
1450 if (pos == MDS_DIR_END_OFF) {
1451
1452
1453
1454 ll_release_page(page, 0);
1455 break;
1456 } else if (1) {
1457
1458
1459
1460
1461 ll_release_page(page, le32_to_cpu(dp->ldp_flags) &
1462 LDF_COLLIDE);
1463 page = ll_get_dir_page(dir, pos, &chain);
1464 } else {
1465
1466
1467
1468 LASSERT(le32_to_cpu(dp->ldp_flags) & LDF_COLLIDE);
1469 ll_release_page(page, 1);
1470 }
1471 }
1472
1473out:
1474 ll_dir_chain_fini(&chain);
1475 return rc;
1476}
1477
1478static void
1479ll_sai_unplug(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
1480{
1481 struct ptlrpc_thread *thread = &sai->sai_thread;
1482 struct ll_sb_info *sbi = ll_i2sbi(sai->sai_inode);
1483 int hit;
1484
1485 if (entry != NULL && entry->se_stat == SA_ENTRY_SUCC)
1486 hit = 1;
1487 else
1488 hit = 0;
1489
1490 ll_sa_entry_fini(sai, entry);
1491 if (hit) {
1492 sai->sai_hit++;
1493 sai->sai_consecutive_miss = 0;
1494 sai->sai_max = min(2 * sai->sai_max, sbi->ll_sa_max);
1495 } else {
1496 struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
1497
1498 sai->sai_miss++;
1499 sai->sai_consecutive_miss++;
1500 if (sa_low_hit(sai) && thread_is_running(thread)) {
1501 atomic_inc(&sbi->ll_sa_wrong);
1502 CDEBUG(D_READA, "Statahead for dir " DFID " hit ratio too low: hit/miss %llu/%llu, sent/replied %llu/%llu, stopping statahead thread\n",
1503 PFID(&lli->lli_fid), sai->sai_hit,
1504 sai->sai_miss, sai->sai_sent,
1505 sai->sai_replied);
1506 spin_lock(&lli->lli_sa_lock);
1507 if (!thread_is_stopped(thread))
1508 thread_set_flags(thread, SVC_STOPPING);
1509 spin_unlock(&lli->lli_sa_lock);
1510 }
1511 }
1512
1513 if (!thread_is_stopped(thread))
1514 wake_up(&thread->t_ctl_waitq);
1515}
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526int do_statahead_enter(struct inode *dir, struct dentry **dentryp,
1527 int only_unplug)
1528{
1529 struct ll_inode_info *lli = ll_i2info(dir);
1530 struct ll_statahead_info *sai = lli->lli_sai;
1531 struct dentry *parent;
1532 struct ll_sa_entry *entry;
1533 struct ptlrpc_thread *thread;
1534 struct l_wait_info lwi = { 0 };
1535 int rc = 0;
1536 struct ll_inode_info *plli;
1537
1538 LASSERT(lli->lli_opendir_pid == current_pid());
1539
1540 if (sai) {
1541 thread = &sai->sai_thread;
1542 if (unlikely(thread_is_stopped(thread) &&
1543 list_empty(&sai->sai_entries_stated))) {
1544
1545 ll_stop_statahead(dir, lli->lli_opendir_key);
1546 return -EAGAIN;
1547 }
1548
1549 if ((*dentryp)->d_name.name[0] == '.') {
1550 if (sai->sai_ls_all ||
1551 sai->sai_miss_hidden >= sai->sai_skip_hidden) {
1552
1553
1554
1555
1556
1557 } else {
1558 if (!sai->sai_ls_all)
1559
1560
1561
1562
1563
1564
1565 sai->sai_ls_all = 1;
1566
1567
1568
1569
1570
1571 sai->sai_miss_hidden++;
1572 return -EAGAIN;
1573 }
1574 }
1575
1576 entry = ll_sa_entry_get_byname(sai, &(*dentryp)->d_name);
1577 if (entry == NULL || only_unplug) {
1578 ll_sai_unplug(sai, entry);
1579 return entry ? 1 : -EAGAIN;
1580 }
1581
1582 if (!ll_sa_entry_stated(entry)) {
1583 sai->sai_index_wait = entry->se_index;
1584 lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(30), NULL,
1585 LWI_ON_SIGNAL_NOOP, NULL);
1586 rc = l_wait_event(sai->sai_waitq,
1587 ll_sa_entry_stated(entry) ||
1588 thread_is_stopped(thread),
1589 &lwi);
1590 if (rc < 0) {
1591 ll_sai_unplug(sai, entry);
1592 return -EAGAIN;
1593 }
1594 }
1595
1596 if (entry->se_stat == SA_ENTRY_SUCC &&
1597 entry->se_inode != NULL) {
1598 struct inode *inode = entry->se_inode;
1599 struct lookup_intent it = { .it_op = IT_GETATTR,
1600 .d.lustre.it_lock_handle =
1601 entry->se_handle };
1602 __u64 bits;
1603
1604 rc = md_revalidate_lock(ll_i2mdexp(dir), &it,
1605 ll_inode2fid(inode), &bits);
1606 if (rc == 1) {
1607 if (d_inode(*dentryp) == NULL) {
1608 struct dentry *alias;
1609
1610 alias = ll_splice_alias(inode,
1611 *dentryp);
1612 if (IS_ERR(alias)) {
1613 ll_sai_unplug(sai, entry);
1614 return PTR_ERR(alias);
1615 }
1616 *dentryp = alias;
1617 } else if (d_inode(*dentryp) != inode) {
1618
1619 CDEBUG(D_READA,
1620 "stale dentry %pd inode %lu/%u, statahead inode %lu/%u\n",
1621 *dentryp,
1622 d_inode(*dentryp)->i_ino,
1623 d_inode(*dentryp)->i_generation,
1624 inode->i_ino,
1625 inode->i_generation);
1626 ll_sai_unplug(sai, entry);
1627 return -ESTALE;
1628 } else {
1629 iput(inode);
1630 }
1631 entry->se_inode = NULL;
1632
1633 if ((bits & MDS_INODELOCK_LOOKUP) &&
1634 d_lustre_invalid(*dentryp))
1635 d_lustre_revalidate(*dentryp);
1636 ll_intent_release(&it);
1637 }
1638 }
1639
1640 ll_sai_unplug(sai, entry);
1641 return rc;
1642 }
1643
1644
1645 rc = is_first_dirent(dir, *dentryp);
1646 if (rc == LS_NONE_FIRST_DE) {
1647
1648 rc = -EAGAIN;
1649 goto out;
1650 }
1651
1652 sai = ll_sai_alloc();
1653 if (sai == NULL) {
1654 rc = -ENOMEM;
1655 goto out;
1656 }
1657
1658 sai->sai_ls_all = (rc == LS_FIRST_DOT_DE);
1659 sai->sai_inode = igrab(dir);
1660 if (unlikely(sai->sai_inode == NULL)) {
1661 CWARN("Do not start stat ahead on dying inode "DFID"\n",
1662 PFID(&lli->lli_fid));
1663 rc = -ESTALE;
1664 goto out;
1665 }
1666
1667
1668 parent = dget((*dentryp)->d_parent);
1669 if (unlikely(sai->sai_inode != d_inode(parent))) {
1670 struct ll_inode_info *nlli = ll_i2info(d_inode(parent));
1671
1672 CWARN("Race condition, someone changed %pd just now: old parent "DFID", new parent "DFID"\n",
1673 *dentryp,
1674 PFID(&lli->lli_fid), PFID(&nlli->lli_fid));
1675 dput(parent);
1676 iput(sai->sai_inode);
1677 rc = -EAGAIN;
1678 goto out;
1679 }
1680
1681 CDEBUG(D_READA, "start statahead thread: sai %p, parent %pd\n",
1682 sai, parent);
1683
1684
1685
1686
1687
1688
1689 ll_sai_get(sai);
1690 lli->lli_sai = sai;
1691
1692 plli = ll_i2info(d_inode(parent));
1693 rc = PTR_ERR(kthread_run(ll_statahead_thread, parent,
1694 "ll_sa_%u", plli->lli_opendir_pid));
1695 thread = &sai->sai_thread;
1696 if (IS_ERR_VALUE(rc)) {
1697 CERROR("can't start ll_sa thread, rc: %d\n", rc);
1698 dput(parent);
1699 lli->lli_opendir_key = NULL;
1700 thread_set_flags(thread, SVC_STOPPED);
1701 thread_set_flags(&sai->sai_agl_thread, SVC_STOPPED);
1702
1703
1704 ll_sai_put(sai);
1705 ll_sai_put(sai);
1706 LASSERT(lli->lli_sai == NULL);
1707 return -EAGAIN;
1708 }
1709
1710 l_wait_event(thread->t_ctl_waitq,
1711 thread_is_running(thread) || thread_is_stopped(thread),
1712 &lwi);
1713 ll_sai_put(sai);
1714
1715
1716
1717
1718
1719 return -EAGAIN;
1720
1721out:
1722 kfree(sai);
1723 spin_lock(&lli->lli_sa_lock);
1724 lli->lli_opendir_key = NULL;
1725 lli->lli_opendir_pid = 0;
1726 spin_unlock(&lli->lli_sa_lock);
1727 return rc;
1728}
1729