aboutsummaryrefslogtreecommitdiffstats
path: root/fs/jbd/checkpoint.c
diff options
context:
space:
mode:
authorMark Fasheh <mark.fasheh@oracle.com>2006-02-14 16:53:03 -0500
committerLinus Torvalds <torvalds@g5.osdl.org>2006-02-14 19:09:34 -0500
commit7c8903f6373f9abecf060bad53ca36bc4ac037f2 (patch)
tree473644b1f2999e3e516cd4f55a3535d9bb29595d /fs/jbd/checkpoint.c
parentbe5efffb762fa4a7b9a7a45ebf34b13e3bf5a2d8 (diff)
[PATCH] jbd: revert checkpoint list changes
This patch reverts commit f93ea411b73594f7d144855fd34278bcf34a9afc: [PATCH] jbd: split checkpoint lists This broke journal_flush() for OCFS2, which is its method of being sure that metadata is sent to disk for another node. And two related commits 8d3c7fce2d20ecc3264c8d8c91ae3beacdeaed1b and 43c3e6f5abdf6acac9b90c86bf03f995bf7d3d92 with the subjects: [PATCH] jbd: log_do_checkpoint fix [PATCH] jbd: remove_transaction fix These seem to be incremental bugfixes on the original patch and as such are no longer needed. Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com> Cc: Jan Kara <jack@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/jbd/checkpoint.c')
-rw-r--r--fs/jbd/checkpoint.c418
1 files changed, 177 insertions, 241 deletions
diff --git a/fs/jbd/checkpoint.c b/fs/jbd/checkpoint.c
index e6265a0b56b8..543ed543d1e5 100644
--- a/fs/jbd/checkpoint.c
+++ b/fs/jbd/checkpoint.c
@@ -24,75 +24,29 @@
24#include <linux/slab.h> 24#include <linux/slab.h>
25 25
26/* 26/*
27 * Unlink a buffer from a transaction checkpoint list. 27 * Unlink a buffer from a transaction.
28 * 28 *
29 * Called with j_list_lock held. 29 * Called with j_list_lock held.
30 */ 30 */
31 31
32static void __buffer_unlink_first(struct journal_head *jh) 32static inline void __buffer_unlink(struct journal_head *jh)
33{ 33{
34 transaction_t *transaction; 34 transaction_t *transaction;
35 35
36 transaction = jh->b_cp_transaction; 36 transaction = jh->b_cp_transaction;
37 jh->b_cp_transaction = NULL;
37 38
38 jh->b_cpnext->b_cpprev = jh->b_cpprev; 39 jh->b_cpnext->b_cpprev = jh->b_cpprev;
39 jh->b_cpprev->b_cpnext = jh->b_cpnext; 40 jh->b_cpprev->b_cpnext = jh->b_cpnext;
40 if (transaction->t_checkpoint_list == jh) { 41 if (transaction->t_checkpoint_list == jh)
41 transaction->t_checkpoint_list = jh->b_cpnext; 42 transaction->t_checkpoint_list = jh->b_cpnext;
42 if (transaction->t_checkpoint_list == jh) 43 if (transaction->t_checkpoint_list == jh)
43 transaction->t_checkpoint_list = NULL; 44 transaction->t_checkpoint_list = NULL;
44 }
45}
46
47/*
48 * Unlink a buffer from a transaction checkpoint(io) list.
49 *
50 * Called with j_list_lock held.
51 */
52
53static inline void __buffer_unlink(struct journal_head *jh)
54{
55 transaction_t *transaction;
56
57 transaction = jh->b_cp_transaction;
58
59 __buffer_unlink_first(jh);
60 if (transaction->t_checkpoint_io_list == jh) {
61 transaction->t_checkpoint_io_list = jh->b_cpnext;
62 if (transaction->t_checkpoint_io_list == jh)
63 transaction->t_checkpoint_io_list = NULL;
64 }
65}
66
67/*
68 * Move a buffer from the checkpoint list to the checkpoint io list
69 *
70 * Called with j_list_lock held
71 */
72
73static inline void __buffer_relink_io(struct journal_head *jh)
74{
75 transaction_t *transaction;
76
77 transaction = jh->b_cp_transaction;
78 __buffer_unlink_first(jh);
79
80 if (!transaction->t_checkpoint_io_list) {
81 jh->b_cpnext = jh->b_cpprev = jh;
82 } else {
83 jh->b_cpnext = transaction->t_checkpoint_io_list;
84 jh->b_cpprev = transaction->t_checkpoint_io_list->b_cpprev;
85 jh->b_cpprev->b_cpnext = jh;
86 jh->b_cpnext->b_cpprev = jh;
87 }
88 transaction->t_checkpoint_io_list = jh;
89} 45}
90 46
91/* 47/*
92 * Try to release a checkpointed buffer from its transaction. 48 * Try to release a checkpointed buffer from its transaction.
93 * Returns 1 if we released it and 2 if we also released the 49 * Returns 1 if we released it.
94 * whole transaction.
95 *
96 * Requires j_list_lock 50 * Requires j_list_lock
97 * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it 51 * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it
98 */ 52 */
@@ -103,11 +57,12 @@ static int __try_to_free_cp_buf(struct journal_head *jh)
103 57
104 if (jh->b_jlist == BJ_None && !buffer_locked(bh) && !buffer_dirty(bh)) { 58 if (jh->b_jlist == BJ_None && !buffer_locked(bh) && !buffer_dirty(bh)) {
105 JBUFFER_TRACE(jh, "remove from checkpoint list"); 59 JBUFFER_TRACE(jh, "remove from checkpoint list");
106 ret = __journal_remove_checkpoint(jh) + 1; 60 __journal_remove_checkpoint(jh);
107 jbd_unlock_bh_state(bh); 61 jbd_unlock_bh_state(bh);
108 journal_remove_journal_head(bh); 62 journal_remove_journal_head(bh);
109 BUFFER_TRACE(bh, "release"); 63 BUFFER_TRACE(bh, "release");
110 __brelse(bh); 64 __brelse(bh);
65 ret = 1;
111 } else { 66 } else {
112 jbd_unlock_bh_state(bh); 67 jbd_unlock_bh_state(bh);
113 } 68 }
@@ -162,53 +117,83 @@ static void jbd_sync_bh(journal_t *journal, struct buffer_head *bh)
162} 117}
163 118
164/* 119/*
165 * Clean up transaction's list of buffers submitted for io. 120 * Clean up a transaction's checkpoint list.
166 * We wait for any pending IO to complete and remove any clean 121 *
167 * buffers. Note that we take the buffers in the opposite ordering 122 * We wait for any pending IO to complete and make sure any clean
168 * from the one in which they were submitted for IO. 123 * buffers are removed from the transaction.
124 *
125 * Return 1 if we performed any actions which might have destroyed the
126 * checkpoint. (journal_remove_checkpoint() deletes the transaction when
127 * the last checkpoint buffer is cleansed)
169 * 128 *
170 * Called with j_list_lock held. 129 * Called with j_list_lock held.
171 */ 130 */
172 131static int __cleanup_transaction(journal_t *journal, transaction_t *transaction)
173static void __wait_cp_io(journal_t *journal, transaction_t *transaction)
174{ 132{
175 struct journal_head *jh; 133 struct journal_head *jh, *next_jh, *last_jh;
176 struct buffer_head *bh; 134 struct buffer_head *bh;
177 tid_t this_tid; 135 int ret = 0;
178 int released = 0; 136
179 137 assert_spin_locked(&journal->j_list_lock);
180 this_tid = transaction->t_tid; 138 jh = transaction->t_checkpoint_list;
181restart: 139 if (!jh)
182 /* Didn't somebody clean up the transaction in the meanwhile */ 140 return 0;
183 if (journal->j_checkpoint_transactions != transaction || 141
184 transaction->t_tid != this_tid) 142 last_jh = jh->b_cpprev;
185 return; 143 next_jh = jh;
186 while (!released && transaction->t_checkpoint_io_list) { 144 do {
187 jh = transaction->t_checkpoint_io_list; 145 jh = next_jh;
188 bh = jh2bh(jh); 146 bh = jh2bh(jh);
189 if (!jbd_trylock_bh_state(bh)) {
190 jbd_sync_bh(journal, bh);
191 spin_lock(&journal->j_list_lock);
192 goto restart;
193 }
194 if (buffer_locked(bh)) { 147 if (buffer_locked(bh)) {
195 atomic_inc(&bh->b_count); 148 atomic_inc(&bh->b_count);
196 spin_unlock(&journal->j_list_lock); 149 spin_unlock(&journal->j_list_lock);
197 jbd_unlock_bh_state(bh);
198 wait_on_buffer(bh); 150 wait_on_buffer(bh);
199 /* the journal_head may have gone by now */ 151 /* the journal_head may have gone by now */
200 BUFFER_TRACE(bh, "brelse"); 152 BUFFER_TRACE(bh, "brelse");
201 __brelse(bh); 153 __brelse(bh);
202 spin_lock(&journal->j_list_lock); 154 goto out_return_1;
203 goto restart;
204 } 155 }
156
205 /* 157 /*
206 * Now in whatever state the buffer currently is, we know that 158 * This is foul
207 * it has been written out and so we can drop it from the list
208 */ 159 */
209 released = __journal_remove_checkpoint(jh); 160 if (!jbd_trylock_bh_state(bh)) {
210 jbd_unlock_bh_state(bh); 161 jbd_sync_bh(journal, bh);
211 } 162 goto out_return_1;
163 }
164
165 if (jh->b_transaction != NULL) {
166 transaction_t *t = jh->b_transaction;
167 tid_t tid = t->t_tid;
168
169 spin_unlock(&journal->j_list_lock);
170 jbd_unlock_bh_state(bh);
171 log_start_commit(journal, tid);
172 log_wait_commit(journal, tid);
173 goto out_return_1;
174 }
175
176 /*
177 * AKPM: I think the buffer_jbddirty test is redundant - it
178 * shouldn't have NULL b_transaction?
179 */
180 next_jh = jh->b_cpnext;
181 if (!buffer_dirty(bh) && !buffer_jbddirty(bh)) {
182 BUFFER_TRACE(bh, "remove from checkpoint");
183 __journal_remove_checkpoint(jh);
184 jbd_unlock_bh_state(bh);
185 journal_remove_journal_head(bh);
186 __brelse(bh);
187 ret = 1;
188 } else {
189 jbd_unlock_bh_state(bh);
190 }
191 } while (jh != last_jh);
192
193 return ret;
194out_return_1:
195 spin_lock(&journal->j_list_lock);
196 return 1;
212} 197}
213 198
214#define NR_BATCH 64 199#define NR_BATCH 64
@@ -218,7 +203,9 @@ __flush_batch(journal_t *journal, struct buffer_head **bhs, int *batch_count)
218{ 203{
219 int i; 204 int i;
220 205
206 spin_unlock(&journal->j_list_lock);
221 ll_rw_block(SWRITE, *batch_count, bhs); 207 ll_rw_block(SWRITE, *batch_count, bhs);
208 spin_lock(&journal->j_list_lock);
222 for (i = 0; i < *batch_count; i++) { 209 for (i = 0; i < *batch_count; i++) {
223 struct buffer_head *bh = bhs[i]; 210 struct buffer_head *bh = bhs[i];
224 clear_buffer_jwrite(bh); 211 clear_buffer_jwrite(bh);
@@ -234,46 +221,19 @@ __flush_batch(journal_t *journal, struct buffer_head **bhs, int *batch_count)
234 * Return 1 if something happened which requires us to abort the current 221 * Return 1 if something happened which requires us to abort the current
235 * scan of the checkpoint list. 222 * scan of the checkpoint list.
236 * 223 *
237 * Called with j_list_lock held and drops it if 1 is returned 224 * Called with j_list_lock held.
238 * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it 225 * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it
239 */ 226 */
240static int __process_buffer(journal_t *journal, struct journal_head *jh, 227static int __flush_buffer(journal_t *journal, struct journal_head *jh,
241 struct buffer_head **bhs, int *batch_count) 228 struct buffer_head **bhs, int *batch_count,
229 int *drop_count)
242{ 230{
243 struct buffer_head *bh = jh2bh(jh); 231 struct buffer_head *bh = jh2bh(jh);
244 int ret = 0; 232 int ret = 0;
245 233
246 if (buffer_locked(bh)) { 234 if (buffer_dirty(bh) && !buffer_locked(bh) && jh->b_jlist == BJ_None) {
247 get_bh(bh); 235 J_ASSERT_JH(jh, jh->b_transaction == NULL);
248 spin_unlock(&journal->j_list_lock);
249 jbd_unlock_bh_state(bh);
250 wait_on_buffer(bh);
251 /* the journal_head may have gone by now */
252 BUFFER_TRACE(bh, "brelse");
253 put_bh(bh);
254 ret = 1;
255 }
256 else if (jh->b_transaction != NULL) {
257 transaction_t *t = jh->b_transaction;
258 tid_t tid = t->t_tid;
259 236
260 spin_unlock(&journal->j_list_lock);
261 jbd_unlock_bh_state(bh);
262 log_start_commit(journal, tid);
263 log_wait_commit(journal, tid);
264 ret = 1;
265 }
266 else if (!buffer_dirty(bh)) {
267 J_ASSERT_JH(jh, !buffer_jbddirty(bh));
268 BUFFER_TRACE(bh, "remove from checkpoint");
269 __journal_remove_checkpoint(jh);
270 spin_unlock(&journal->j_list_lock);
271 jbd_unlock_bh_state(bh);
272 journal_remove_journal_head(bh);
273 put_bh(bh);
274 ret = 1;
275 }
276 else {
277 /* 237 /*
278 * Important: we are about to write the buffer, and 238 * Important: we are about to write the buffer, and
279 * possibly block, while still holding the journal lock. 239 * possibly block, while still holding the journal lock.
@@ -286,30 +246,45 @@ static int __process_buffer(journal_t *journal, struct journal_head *jh,
286 J_ASSERT_BH(bh, !buffer_jwrite(bh)); 246 J_ASSERT_BH(bh, !buffer_jwrite(bh));
287 set_buffer_jwrite(bh); 247 set_buffer_jwrite(bh);
288 bhs[*batch_count] = bh; 248 bhs[*batch_count] = bh;
289 __buffer_relink_io(jh);
290 jbd_unlock_bh_state(bh); 249 jbd_unlock_bh_state(bh);
291 (*batch_count)++; 250 (*batch_count)++;
292 if (*batch_count == NR_BATCH) { 251 if (*batch_count == NR_BATCH) {
293 spin_unlock(&journal->j_list_lock);
294 __flush_batch(journal, bhs, batch_count); 252 __flush_batch(journal, bhs, batch_count);
295 ret = 1; 253 ret = 1;
296 } 254 }
255 } else {
256 int last_buffer = 0;
257 if (jh->b_cpnext == jh) {
258 /* We may be about to drop the transaction. Tell the
259 * caller that the lists have changed.
260 */
261 last_buffer = 1;
262 }
263 if (__try_to_free_cp_buf(jh)) {
264 (*drop_count)++;
265 ret = last_buffer;
266 }
297 } 267 }
298 return ret; 268 return ret;
299} 269}
300 270
301/* 271/*
302 * Perform an actual checkpoint. We take the first transaction on the 272 * Perform an actual checkpoint. We don't write out only enough to
303 * list of transactions to be checkpointed and send all its buffers 273 * satisfy the current blocked requests: rather we submit a reasonably
304 * to disk. We submit larger chunks of data at once. 274 * sized chunk of the outstanding data to disk at once for
275 * efficiency. __log_wait_for_space() will retry if we didn't free enough.
305 * 276 *
277 * However, we _do_ take into account the amount requested so that once
278 * the IO has been queued, we can return as soon as enough of it has
279 * completed to disk.
280 *
306 * The journal should be locked before calling this function. 281 * The journal should be locked before calling this function.
307 */ 282 */
308int log_do_checkpoint(journal_t *journal) 283int log_do_checkpoint(journal_t *journal)
309{ 284{
310 transaction_t *transaction;
311 tid_t this_tid;
312 int result; 285 int result;
286 int batch_count = 0;
287 struct buffer_head *bhs[NR_BATCH];
313 288
314 jbd_debug(1, "Start checkpoint\n"); 289 jbd_debug(1, "Start checkpoint\n");
315 290
@@ -324,70 +299,79 @@ int log_do_checkpoint(journal_t *journal)
324 return result; 299 return result;
325 300
326 /* 301 /*
327 * OK, we need to start writing disk blocks. Take one transaction 302 * OK, we need to start writing disk blocks. Try to free up a
328 * and write it. 303 * quarter of the log in a single checkpoint if we can.
329 */ 304 */
330 spin_lock(&journal->j_list_lock);
331 if (!journal->j_checkpoint_transactions)
332 goto out;
333 transaction = journal->j_checkpoint_transactions;
334 this_tid = transaction->t_tid;
335restart:
336 /* 305 /*
337 * If someone cleaned up this transaction while we slept, we're 306 * AKPM: check this code. I had a feeling a while back that it
338 * done (maybe it's a new transaction, but it fell at the same 307 * degenerates into a busy loop at unmount time.
339 * address).
340 */ 308 */
341 if (journal->j_checkpoint_transactions == transaction && 309 spin_lock(&journal->j_list_lock);
342 transaction->t_tid == this_tid) { 310 while (journal->j_checkpoint_transactions) {
343 int batch_count = 0; 311 transaction_t *transaction;
344 struct buffer_head *bhs[NR_BATCH]; 312 struct journal_head *jh, *last_jh, *next_jh;
345 struct journal_head *jh; 313 int drop_count = 0;
346 int retry = 0; 314 int cleanup_ret, retry = 0;
347 315 tid_t this_tid;
348 while (!retry && transaction->t_checkpoint_list) { 316
317 transaction = journal->j_checkpoint_transactions;
318 this_tid = transaction->t_tid;
319 jh = transaction->t_checkpoint_list;
320 last_jh = jh->b_cpprev;
321 next_jh = jh;
322 do {
349 struct buffer_head *bh; 323 struct buffer_head *bh;
350 324
351 jh = transaction->t_checkpoint_list; 325 jh = next_jh;
326 next_jh = jh->b_cpnext;
352 bh = jh2bh(jh); 327 bh = jh2bh(jh);
353 if (!jbd_trylock_bh_state(bh)) { 328 if (!jbd_trylock_bh_state(bh)) {
354 jbd_sync_bh(journal, bh); 329 jbd_sync_bh(journal, bh);
330 spin_lock(&journal->j_list_lock);
355 retry = 1; 331 retry = 1;
356 break; 332 break;
357 } 333 }
358 retry = __process_buffer(journal, jh, bhs, 334 retry = __flush_buffer(journal, jh, bhs, &batch_count, &drop_count);
359 &batch_count); 335 if (cond_resched_lock(&journal->j_list_lock)) {
360 if (!retry &&
361 lock_need_resched(&journal->j_list_lock)) {
362 spin_unlock(&journal->j_list_lock);
363 retry = 1; 336 retry = 1;
364 break; 337 break;
365 } 338 }
366 } 339 } while (jh != last_jh && !retry);
367 340
368 if (batch_count) { 341 if (batch_count) {
369 if (!retry) {
370 spin_unlock(&journal->j_list_lock);
371 retry = 1;
372 }
373 __flush_batch(journal, bhs, &batch_count); 342 __flush_batch(journal, bhs, &batch_count);
343 retry = 1;
374 } 344 }
375 345
376 if (retry) {
377 spin_lock(&journal->j_list_lock);
378 goto restart;
379 }
380 /* 346 /*
381 * Now we have cleaned up the first transaction's checkpoint 347 * If someone cleaned up this transaction while we slept, we're
382 * list. Let's clean up the second one. 348 * done
349 */
350 if (journal->j_checkpoint_transactions != transaction)
351 break;
352 if (retry)
353 continue;
354 /*
355 * Maybe it's a new transaction, but it fell at the same
356 * address
383 */ 357 */
384 __wait_cp_io(journal, transaction); 358 if (transaction->t_tid != this_tid)
359 continue;
360 /*
361 * We have walked the whole transaction list without
362 * finding anything to write to disk. We had better be
363 * able to make some progress or we are in trouble.
364 */
365 cleanup_ret = __cleanup_transaction(journal, transaction);
366 J_ASSERT(drop_count != 0 || cleanup_ret != 0);
367 if (journal->j_checkpoint_transactions != transaction)
368 break;
385 } 369 }
386out:
387 spin_unlock(&journal->j_list_lock); 370 spin_unlock(&journal->j_list_lock);
388 result = cleanup_journal_tail(journal); 371 result = cleanup_journal_tail(journal);
389 if (result < 0) 372 if (result < 0)
390 return result; 373 return result;
374
391 return 0; 375 return 0;
392} 376}
393 377
@@ -472,91 +456,52 @@ int cleanup_journal_tail(journal_t *journal)
472/* Checkpoint list management */ 456/* Checkpoint list management */
473 457
474/* 458/*
475 * journal_clean_one_cp_list
476 *
477 * Find all the written-back checkpoint buffers in the given list and release them.
478 *
479 * Called with the journal locked.
480 * Called with j_list_lock held.
481 * Returns number of bufers reaped (for debug)
482 */
483
484static int journal_clean_one_cp_list(struct journal_head *jh, int *released)
485{
486 struct journal_head *last_jh;
487 struct journal_head *next_jh = jh;
488 int ret, freed = 0;
489
490 *released = 0;
491 if (!jh)
492 return 0;
493
494 last_jh = jh->b_cpprev;
495 do {
496 jh = next_jh;
497 next_jh = jh->b_cpnext;
498 /* Use trylock because of the ranking */
499 if (jbd_trylock_bh_state(jh2bh(jh))) {
500 ret = __try_to_free_cp_buf(jh);
501 if (ret) {
502 freed++;
503 if (ret == 2) {
504 *released = 1;
505 return freed;
506 }
507 }
508 }
509 /*
510 * This function only frees up some memory if possible so we
511 * dont have an obligation to finish processing. Bail out if
512 * preemption requested:
513 */
514 if (need_resched())
515 return freed;
516 } while (jh != last_jh);
517
518 return freed;
519}
520
521/*
522 * journal_clean_checkpoint_list 459 * journal_clean_checkpoint_list
523 * 460 *
524 * Find all the written-back checkpoint buffers in the journal and release them. 461 * Find all the written-back checkpoint buffers in the journal and release them.
525 * 462 *
526 * Called with the journal locked. 463 * Called with the journal locked.
527 * Called with j_list_lock held. 464 * Called with j_list_lock held.
528 * Returns number of buffers reaped (for debug) 465 * Returns number of bufers reaped (for debug)
529 */ 466 */
530 467
531int __journal_clean_checkpoint_list(journal_t *journal) 468int __journal_clean_checkpoint_list(journal_t *journal)
532{ 469{
533 transaction_t *transaction, *last_transaction, *next_transaction; 470 transaction_t *transaction, *last_transaction, *next_transaction;
534 int ret = 0, released; 471 int ret = 0;
535 472
536 transaction = journal->j_checkpoint_transactions; 473 transaction = journal->j_checkpoint_transactions;
537 if (!transaction) 474 if (transaction == 0)
538 goto out; 475 goto out;
539 476
540 last_transaction = transaction->t_cpprev; 477 last_transaction = transaction->t_cpprev;
541 next_transaction = transaction; 478 next_transaction = transaction;
542 do { 479 do {
480 struct journal_head *jh;
481
543 transaction = next_transaction; 482 transaction = next_transaction;
544 next_transaction = transaction->t_cpnext; 483 next_transaction = transaction->t_cpnext;
545 ret += journal_clean_one_cp_list(transaction-> 484 jh = transaction->t_checkpoint_list;
546 t_checkpoint_list, &released); 485 if (jh) {
547 if (need_resched()) 486 struct journal_head *last_jh = jh->b_cpprev;
548 goto out; 487 struct journal_head *next_jh = jh;
549 if (released) 488
550 continue; 489 do {
551 /* 490 jh = next_jh;
552 * It is essential that we are as careful as in the case of 491 next_jh = jh->b_cpnext;
553 * t_checkpoint_list with removing the buffer from the list as 492 /* Use trylock because of the ranknig */
554 * we can possibly see not yet submitted buffers on io_list 493 if (jbd_trylock_bh_state(jh2bh(jh)))
555 */ 494 ret += __try_to_free_cp_buf(jh);
556 ret += journal_clean_one_cp_list(transaction-> 495 /*
557 t_checkpoint_io_list, &released); 496 * This function only frees up some memory
558 if (need_resched()) 497 * if possible so we dont have an obligation
559 goto out; 498 * to finish processing. Bail out if preemption
499 * requested:
500 */
501 if (need_resched())
502 goto out;
503 } while (jh != last_jh);
504 }
560 } while (transaction != last_transaction); 505 } while (transaction != last_transaction);
561out: 506out:
562 return ret; 507 return ret;
@@ -571,22 +516,18 @@ out:
571 * buffer updates committed in that transaction have safely been stored 516 * buffer updates committed in that transaction have safely been stored
572 * elsewhere on disk. To achieve this, all of the buffers in a 517 * elsewhere on disk. To achieve this, all of the buffers in a
573 * transaction need to be maintained on the transaction's checkpoint 518 * transaction need to be maintained on the transaction's checkpoint
574 * lists until they have been rewritten, at which point this function is 519 * list until they have been rewritten, at which point this function is
575 * called to remove the buffer from the existing transaction's 520 * called to remove the buffer from the existing transaction's
576 * checkpoint lists. 521 * checkpoint list.
577 *
578 * The function returns 1 if it frees the transaction, 0 otherwise.
579 * 522 *
580 * This function is called with the journal locked. 523 * This function is called with the journal locked.
581 * This function is called with j_list_lock held. 524 * This function is called with j_list_lock held.
582 * This function is called with jbd_lock_bh_state(jh2bh(jh))
583 */ 525 */
584 526
585int __journal_remove_checkpoint(struct journal_head *jh) 527void __journal_remove_checkpoint(struct journal_head *jh)
586{ 528{
587 transaction_t *transaction; 529 transaction_t *transaction;
588 journal_t *journal; 530 journal_t *journal;
589 int ret = 0;
590 531
591 JBUFFER_TRACE(jh, "entry"); 532 JBUFFER_TRACE(jh, "entry");
592 533
@@ -597,10 +538,8 @@ int __journal_remove_checkpoint(struct journal_head *jh)
597 journal = transaction->t_journal; 538 journal = transaction->t_journal;
598 539
599 __buffer_unlink(jh); 540 __buffer_unlink(jh);
600 jh->b_cp_transaction = NULL;
601 541
602 if (transaction->t_checkpoint_list != NULL || 542 if (transaction->t_checkpoint_list != NULL)
603 transaction->t_checkpoint_io_list != NULL)
604 goto out; 543 goto out;
605 JBUFFER_TRACE(jh, "transaction has no more buffers"); 544 JBUFFER_TRACE(jh, "transaction has no more buffers");
606 545
@@ -626,10 +565,8 @@ int __journal_remove_checkpoint(struct journal_head *jh)
626 /* Just in case anybody was waiting for more transactions to be 565 /* Just in case anybody was waiting for more transactions to be
627 checkpointed... */ 566 checkpointed... */
628 wake_up(&journal->j_wait_logspace); 567 wake_up(&journal->j_wait_logspace);
629 ret = 1;
630out: 568out:
631 JBUFFER_TRACE(jh, "exit"); 569 JBUFFER_TRACE(jh, "exit");
632 return ret;
633} 570}
634 571
635/* 572/*
@@ -691,7 +628,6 @@ void __journal_drop_transaction(journal_t *journal, transaction_t *transaction)
691 J_ASSERT(transaction->t_shadow_list == NULL); 628 J_ASSERT(transaction->t_shadow_list == NULL);
692 J_ASSERT(transaction->t_log_list == NULL); 629 J_ASSERT(transaction->t_log_list == NULL);
693 J_ASSERT(transaction->t_checkpoint_list == NULL); 630 J_ASSERT(transaction->t_checkpoint_list == NULL);
694 J_ASSERT(transaction->t_checkpoint_io_list == NULL);
695 J_ASSERT(transaction->t_updates == 0); 631 J_ASSERT(transaction->t_updates == 0);
696 J_ASSERT(journal->j_committing_transaction != transaction); 632 J_ASSERT(journal->j_committing_transaction != transaction);
697 J_ASSERT(journal->j_running_transaction != transaction); 633 J_ASSERT(journal->j_running_transaction != transaction);