FEX-Emu/linux
1
0
Fork 0
mirror of https://github.com/FEX-Emu/linux.git synced 2024-12-27 20:07:09 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Merge tag 'md/4.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md

Browse Source 
Pull MD fixes from Shaohua Li:
 "This fixes several corner cases for raid5 cache, which is merged into
  this cycle"

* tag 'md/4.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  md/r5cache: disable write back for degraded array
  md/r5cache: shift complex rmw from read path to write path
  md/r5cache: flush data only stripes in r5l_recovery_log()
  md/raid5: move comment of fetch_block to right location
  md/r5cache: read data into orig_page for prexor of cached data
  md/raid5-cache: delete meaningless code
This commit is contained in:
Linus Torvalds 2017-01-28 11:09:04 -08:00
commit dd55396267
4 changed files with 194 additions and 45 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/md/md.c
View File

@ -5291,6 +5291,11 @@ int md_run(struct mddev *mddev)
if (start_readonly && mddev->ro == 0)
mddev->ro = 2; /* read-only, but switch on first write */
/*
* NOTE: some pers->run(), for example r5l_recovery_log(), wakes
* up mddev->thread. It is important to initialize critical
* resources for mddev->thread BEFORE calling pers->run().
*/
err = pers->run(mddev);
if (err)
pr_warn("md: pers->run() failed ...\n");

106
drivers/md/raid5-cache.c
View File

@ -162,6 +162,8 @@ struct r5l_log {
/* to submit async io_units, to fulfill ordering of flush */
struct work_struct deferred_io_work;
/* to disable write back during in degraded mode */
struct work_struct disable_writeback_work;
};
/*
@ -611,6 +613,21 @@ static void r5l_submit_io_async(struct work_struct *work)
r5l_do_submit_io(log, io);
}
static void r5c_disable_writeback_async(struct work_struct *work)
{
struct r5l_log *log = container_of(work, struct r5l_log,
disable_writeback_work);
struct mddev *mddev = log->rdev->mddev;
if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH)
return;
pr_info("md/raid:%s: Disabling writeback cache for degraded array.\n",
mdname(mddev));
mddev_suspend(mddev);
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
mddev_resume(mddev);
}
static void r5l_submit_current_io(struct r5l_log *log)
{
struct r5l_io_unit *io = log->current_io;
@ -1393,8 +1410,6 @@ static void r5l_do_reclaim(struct r5l_log *log)
next_checkpoint = r5c_calculate_new_cp(conf);
spin_unlock_irq(&log->io_list_lock);
BUG_ON(reclaimable < 0);
if (reclaimable == 0 || !write_super)
return;
@ -2062,7 +2077,7 @@ static int
r5c_recovery_rewrite_data_only_stripes(struct r5l_log *log,
struct r5l_recovery_ctx *ctx)
{
struct stripe_head *sh, *next;
struct stripe_head *sh;
struct mddev *mddev = log->rdev->mddev;
struct page *page;
sector_t next_checkpoint = MaxSector;
@ -2076,7 +2091,7 @@ r5c_recovery_rewrite_data_only_stripes(struct r5l_log *log,
WARN_ON(list_empty(&ctx->cached_list));
list_for_each_entry_safe(sh, next, &ctx->cached_list, lru) {
list_for_each_entry(sh, &ctx->cached_list, lru) {
struct r5l_meta_block *mb;
int i;
int offset;
@ -2126,14 +2141,39 @@ r5c_recovery_rewrite_data_only_stripes(struct r5l_log *log,
ctx->pos = write_pos;
ctx->seq += 1;
next_checkpoint = sh->log_start;
list_del_init(&sh->lru);
raid5_release_stripe(sh);
}
log->next_checkpoint = next_checkpoint;
__free_page(page);
return 0;
}
static void r5c_recovery_flush_data_only_stripes(struct r5l_log *log,
struct r5l_recovery_ctx *ctx)
{
struct mddev *mddev = log->rdev->mddev;
struct r5conf *conf = mddev->private;
struct stripe_head *sh, *next;
if (ctx->data_only_stripes == 0)
return;
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_BACK;
list_for_each_entry_safe(sh, next, &ctx->cached_list, lru) {
r5c_make_stripe_write_out(sh);
set_bit(STRIPE_HANDLE, &sh->state);
list_del_init(&sh->lru);
raid5_release_stripe(sh);
}
md_wakeup_thread(conf->mddev->thread);
/* reuse conf->wait_for_quiescent in recovery */
wait_event(conf->wait_for_quiescent,
atomic_read(&conf->active_stripes) == 0);
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
}
static int r5l_recovery_log(struct r5l_log *log)
{
struct mddev *mddev = log->rdev->mddev;
@ -2160,32 +2200,31 @@ static int r5l_recovery_log(struct r5l_log *log)
pos = ctx.pos;
ctx.seq += 10000;
if (ctx.data_only_stripes == 0) {
log->next_checkpoint = ctx.pos;
r5l_log_write_empty_meta_block(log, ctx.pos, ctx.seq++);
ctx.pos = r5l_ring_add(log, ctx.pos, BLOCK_SECTORS);
}
if ((ctx.data_only_stripes == 0) && (ctx.data_parity_stripes == 0))
pr_debug("md/raid:%s: starting from clean shutdown\n",
mdname(mddev));
else {
else
pr_debug("md/raid:%s: recovering %d data-only stripes and %d data-parity stripes\n",
mdname(mddev), ctx.data_only_stripes,
ctx.data_parity_stripes);
if (ctx.data_only_stripes > 0)
if (r5c_recovery_rewrite_data_only_stripes(log, &ctx)) {
pr_err("md/raid:%s: failed to rewrite stripes to journal\n",
mdname(mddev));
return -EIO;
}
if (ctx.data_only_stripes == 0) {
log->next_checkpoint = ctx.pos;
r5l_log_write_empty_meta_block(log, ctx.pos, ctx.seq++);
ctx.pos = r5l_ring_add(log, ctx.pos, BLOCK_SECTORS);
} else if (r5c_recovery_rewrite_data_only_stripes(log, &ctx)) {
pr_err("md/raid:%s: failed to rewrite stripes to journal\n",
mdname(mddev));
return -EIO;
}
log->log_start = ctx.pos;
log->seq = ctx.seq;
log->last_checkpoint = pos;
r5l_write_super(log, pos);
r5c_recovery_flush_data_only_stripes(log, &ctx);
return 0;
}
@ -2247,6 +2286,10 @@ static ssize_t r5c_journal_mode_store(struct mddev *mddev,
val > R5C_JOURNAL_MODE_WRITE_BACK)
return -EINVAL;
if (raid5_calc_degraded(conf) > 0 &&
val == R5C_JOURNAL_MODE_WRITE_BACK)
return -EINVAL;
mddev_suspend(mddev);
conf->log->r5c_journal_mode = val;
mddev_resume(mddev);
@ -2301,6 +2344,16 @@ int r5c_try_caching_write(struct r5conf *conf,
set_bit(STRIPE_R5C_CACHING, &sh->state);
}
/*
* When run in degraded mode, array is set to write-through mode.
* This check helps drain pending write safely in the transition to
* write-through mode.
*/
if (s->failed) {
r5c_make_stripe_write_out(sh);
return -EAGAIN;
}
for (i = disks; i--; ) {
dev = &sh->dev[i];
/* if non-overwrite, use writing-out phase */
@ -2351,6 +2404,8 @@ void r5c_release_extra_page(struct stripe_head *sh)
struct page *p = sh->dev[i].orig_page;
sh->dev[i].orig_page = sh->dev[i].page;
clear_bit(R5_OrigPageUPTDODATE, &sh->dev[i].flags);
if (!using_disk_info_extra_page)
put_page(p);
}
@ -2555,6 +2610,19 @@ ioerr:
return ret;
}
void r5c_update_on_rdev_error(struct mddev *mddev)
{
struct r5conf *conf = mddev->private;
struct r5l_log *log = conf->log;
if (!log)
return;
if (raid5_calc_degraded(conf) > 0 &&
conf->log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK)
schedule_work(&log->disable_writeback_work);
}
int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
{
struct request_queue *q = bdev_get_queue(rdev->bdev);
@ -2627,6 +2695,7 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
spin_lock_init(&log->no_space_stripes_lock);
INIT_WORK(&log->deferred_io_work, r5l_submit_io_async);
INIT_WORK(&log->disable_writeback_work, r5c_disable_writeback_async);
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
INIT_LIST_HEAD(&log->stripe_in_journal_list);
@ -2659,6 +2728,7 @@ io_kc:
void r5l_exit_log(struct r5l_log *log)
{
flush_work(&log->disable_writeback_work);
md_unregister_thread(&log->reclaim_thread);
mempool_destroy(log->meta_pool);
bioset_free(log->bs);

121
drivers/md/raid5.c
View File

@ -556,7 +556,7 @@ static struct stripe_head *__find_stripe(struct r5conf *conf, sector_t sector,
* of the two sections, and some non-in_sync devices may
* be insync in the section most affected by failed devices.
*/
static int calc_degraded(struct r5conf *conf)
int raid5_calc_degraded(struct r5conf *conf)
{
int degraded, degraded2;
int i;
@ -619,7 +619,7 @@ static int has_failed(struct r5conf *conf)
if (conf->mddev->reshape_position == MaxSector)
return conf->mddev->degraded > conf->max_degraded;
degraded = calc_degraded(conf);
degraded = raid5_calc_degraded(conf);
if (degraded > conf->max_degraded)
return 1;
return 0;
@ -1015,7 +1015,17 @@ again:
if (test_bit(R5_SkipCopy, &sh->dev[i].flags))
WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
sh->dev[i].vec.bv_page = sh->dev[i].page;
if (!op_is_write(op) &&
test_bit(R5_InJournal, &sh->dev[i].flags))
/*
* issuing read for a page in journal, this
* must be preparing for prexor in rmw; read
* the data into orig_page
*/
sh->dev[i].vec.bv_page = sh->dev[i].orig_page;
else
sh->dev[i].vec.bv_page = sh->dev[i].page;
bi->bi_vcnt = 1;
bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
bi->bi_io_vec[0].bv_offset = 0;
@ -2380,6 +2390,13 @@ static void raid5_end_read_request(struct bio * bi)
} else if (test_bit(R5_ReadNoMerge, &sh->dev[i].flags))
clear_bit(R5_ReadNoMerge, &sh->dev[i].flags);
if (test_bit(R5_InJournal, &sh->dev[i].flags))
/*
* end read for a page in journal, this
* must be preparing for prexor in rmw
*/
set_bit(R5_OrigPageUPTDODATE, &sh->dev[i].flags);
if (atomic_read(&rdev->read_errors))
atomic_set(&rdev->read_errors, 0);
} else {
@ -2538,7 +2555,7 @@ static void raid5_error(struct mddev *mddev, struct md_rdev *rdev)
spin_lock_irqsave(&conf->device_lock, flags);
clear_bit(In_sync, &rdev->flags);
mddev->degraded = calc_degraded(conf);
mddev->degraded = raid5_calc_degraded(conf);
spin_unlock_irqrestore(&conf->device_lock, flags);
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
@ -2552,6 +2569,7 @@ static void raid5_error(struct mddev *mddev, struct md_rdev *rdev)
bdevname(rdev->bdev, b),
mdname(mddev),
conf->raid_disks - mddev->degraded);
r5c_update_on_rdev_error(mddev);
}
/*
@ -2880,6 +2898,30 @@ sector_t raid5_compute_blocknr(struct stripe_head *sh, int i, int previous)
return r_sector;
}
/*
* There are cases where we want handle_stripe_dirtying() and
* schedule_reconstruction() to delay towrite to some dev of a stripe.
*
* This function checks whether we want to delay the towrite. Specifically,
* we delay the towrite when:
*
* 1. degraded stripe has a non-overwrite to the missing dev, AND this
* stripe has data in journal (for other devices).
*
* In this case, when reading data for the non-overwrite dev, it is
* necessary to handle complex rmw of write back cache (prexor with
* orig_page, and xor with page). To keep read path simple, we would
* like to flush data in journal to RAID disks first, so complex rmw
* is handled in the write patch (handle_stripe_dirtying).
*
*/
static inline bool delay_towrite(struct r5dev *dev,
struct stripe_head_state *s)
{
return !test_bit(R5_OVERWRITE, &dev->flags) &&
!test_bit(R5_Insync, &dev->flags) && s->injournal;
}
static void
schedule_reconstruction(struct stripe_head *sh, struct stripe_head_state *s,
int rcw, int expand)
@ -2900,7 +2942,7 @@ schedule_reconstruction(struct stripe_head *sh, struct stripe_head_state *s,
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
if (dev->towrite) {
if (dev->towrite && !delay_towrite(dev, s)) {
set_bit(R5_LOCKED, &dev->flags);
set_bit(R5_Wantdrain, &dev->flags);
if (!expand)
@ -3295,13 +3337,6 @@ static int want_replace(struct stripe_head *sh, int disk_idx)
return rv;
}
/* fetch_block - checks the given member device to see if its data needs
* to be read or computed to satisfy a request.
*
* Returns 1 when no more member devices need to be checked, otherwise returns
* 0 to tell the loop in handle_stripe_fill to continue
*/
static int need_this_block(struct stripe_head *sh, struct stripe_head_state *s,
int disk_idx, int disks)
{
@ -3392,6 +3427,12 @@ static int need_this_block(struct stripe_head *sh, struct stripe_head_state *s,
return 0;
}
/* fetch_block - checks the given member device to see if its data needs
* to be read or computed to satisfy a request.
*
* Returns 1 when no more member devices need to be checked, otherwise returns
* 0 to tell the loop in handle_stripe_fill to continue
*/
static int fetch_block(struct stripe_head *sh, struct stripe_head_state *s,
int disk_idx, int disks)
{
@ -3478,10 +3519,26 @@ static void handle_stripe_fill(struct stripe_head *sh,
* midst of changing due to a write
*/
if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state &&
!sh->reconstruct_state)
!sh->reconstruct_state) {
/*
* For degraded stripe with data in journal, do not handle
* read requests yet, instead, flush the stripe to raid
* disks first, this avoids handling complex rmw of write
* back cache (prexor with orig_page, and then xor with
* page) in the read path
*/
if (s->injournal && s->failed) {
if (test_bit(STRIPE_R5C_CACHING, &sh->state))
r5c_make_stripe_write_out(sh);
goto out;
}
for (i = disks; i--; )
if (fetch_block(sh, s, i, disks))
break;
}
out:
set_bit(STRIPE_HANDLE, &sh->state);
}
@ -3594,6 +3651,21 @@ unhash:
break_stripe_batch_list(head_sh, STRIPE_EXPAND_SYNC_FLAGS);
}
/*
* For RMW in write back cache, we need extra page in prexor to store the
* old data. This page is stored in dev->orig_page.
*
* This function checks whether we have data for prexor. The exact logic
* is:
* R5_UPTODATE && (!R5_InJournal || R5_OrigPageUPTDODATE)
*/
static inline bool uptodate_for_rmw(struct r5dev *dev)
{
return (test_bit(R5_UPTODATE, &dev->flags)) &&
(!test_bit(R5_InJournal, &dev->flags) ||
test_bit(R5_OrigPageUPTDODATE, &dev->flags));
}
static int handle_stripe_dirtying(struct r5conf *conf,
struct stripe_head *sh,
struct stripe_head_state *s,
@ -3622,12 +3694,11 @@ static int handle_stripe_dirtying(struct r5conf *conf,
} else for (i = disks; i--; ) {
/* would I have to read this buffer for read_modify_write */
struct r5dev *dev = &sh->dev[i];
if ((dev->towrite || i == sh->pd_idx || i == sh->qd_idx ||
if (((dev->towrite && !delay_towrite(dev, s)) ||
i == sh->pd_idx || i == sh->qd_idx ||
test_bit(R5_InJournal, &dev->flags)) &&
!test_bit(R5_LOCKED, &dev->flags) &&
!((test_bit(R5_UPTODATE, &dev->flags) &&
(!test_bit(R5_InJournal, &dev->flags) ||
dev->page != dev->orig_page)) ||
!(uptodate_for_rmw(dev) ||
test_bit(R5_Wantcompute, &dev->flags))) {
if (test_bit(R5_Insync, &dev->flags))
rmw++;
@ -3639,7 +3710,6 @@ static int handle_stripe_dirtying(struct r5conf *conf,
i != sh->pd_idx && i != sh->qd_idx &&
!test_bit(R5_LOCKED, &dev->flags) &&
!(test_bit(R5_UPTODATE, &dev->flags) ||
test_bit(R5_InJournal, &dev->flags) ||
test_bit(R5_Wantcompute, &dev->flags))) {
if (test_bit(R5_Insync, &dev->flags))
rcw++;
@ -3689,13 +3759,11 @@ static int handle_stripe_dirtying(struct r5conf *conf,
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
if ((dev->towrite ||
if (((dev->towrite && !delay_towrite(dev, s)) ||
i == sh->pd_idx || i == sh->qd_idx ||
test_bit(R5_InJournal, &dev->flags)) &&
!test_bit(R5_LOCKED, &dev->flags) &&
!((test_bit(R5_UPTODATE, &dev->flags) &&
(!test_bit(R5_InJournal, &dev->flags) ||
dev->page != dev->orig_page)) ||
!(uptodate_for_rmw(dev) ||
test_bit(R5_Wantcompute, &dev->flags)) &&
test_bit(R5_Insync, &dev->flags)) {
if (test_bit(STRIPE_PREREAD_ACTIVE,
@ -3722,7 +3790,6 @@ static int handle_stripe_dirtying(struct r5conf *conf,
i != sh->pd_idx && i != sh->qd_idx &&
!test_bit(R5_LOCKED, &dev->flags) &&
!(test_bit(R5_UPTODATE, &dev->flags) ||
test_bit(R5_InJournal, &dev->flags) ||
test_bit(R5_Wantcompute, &dev->flags))) {
rcw++;
if (test_bit(R5_Insync, &dev->flags) &&
@ -7025,7 +7092,7 @@ static int raid5_run(struct mddev *mddev)
/*
* 0 for a fully functional array, 1 or 2 for a degraded array.
*/
mddev->degraded = calc_degraded(conf);
mddev->degraded = raid5_calc_degraded(conf);
if (has_failed(conf)) {
pr_crit("md/raid:%s: not enough operational devices (%d/%d failed)\n",
@ -7272,7 +7339,7 @@ static int raid5_spare_active(struct mddev *mddev)
}
}
spin_lock_irqsave(&conf->device_lock, flags);
mddev->degraded = calc_degraded(conf);
mddev->degraded = raid5_calc_degraded(conf);
spin_unlock_irqrestore(&conf->device_lock, flags);
print_raid5_conf(conf);
return count;
@ -7632,7 +7699,7 @@ static int raid5_start_reshape(struct mddev *mddev)
* pre and post number of devices.
*/
spin_lock_irqsave(&conf->device_lock, flags);
mddev->degraded = calc_degraded(conf);
mddev->degraded = raid5_calc_degraded(conf);
spin_unlock_irqrestore(&conf->device_lock, flags);
}
mddev->raid_disks = conf->raid_disks;
@ -7720,7 +7787,7 @@ static void raid5_finish_reshape(struct mddev *mddev)
} else {
int d;
spin_lock_irq(&conf->device_lock);
mddev->degraded = calc_degraded(conf);
mddev->degraded = raid5_calc_degraded(conf);
spin_unlock_irq(&conf->device_lock);
for (d = conf->raid_disks ;
d < conf->raid_disks - mddev->delta_disks;

7
drivers/md/raid5.h
View File

@ -322,6 +322,11 @@ enum r5dev_flags {
* data and parity being written are in the journal
* device
*/
R5_OrigPageUPTDODATE, /* with write back cache, we read old data into
* dev->orig_page for prexor. When this flag is
* set, orig_page contains latest data in the
* raid disk.
*/
};
/*
@ -753,6 +758,7 @@ extern sector_t raid5_compute_sector(struct r5conf *conf, sector_t r_sector,
extern struct stripe_head *
raid5_get_active_stripe(struct r5conf *conf, sector_t sector,
int previous, int noblock, int noquiesce);
extern int raid5_calc_degraded(struct r5conf *conf);
extern int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev);
extern void r5l_exit_log(struct r5l_log *log);
extern int r5l_write_stripe(struct r5l_log *log, struct stripe_head *head_sh);
@ -781,4 +787,5 @@ extern void r5c_flush_cache(struct r5conf *conf, int num);
extern void r5c_check_stripe_cache_usage(struct r5conf *conf);
extern void r5c_check_cached_full_stripe(struct r5conf *conf);
extern struct md_sysfs_entry r5c_journal_mode;
extern void r5c_update_on_rdev_error(struct mddev *mddev);
#endif