drbd: don't count sendpage()d pages only referenced by tcp as in use

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Lars Ellenberg 2010-09-06 12:30:25 +02:00 committed by Philipp Reisner
parent 76d2e7eca8
commit 435f07402b
4 changed files with 27 additions and 12 deletions

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@ -1077,7 +1077,8 @@ struct drbd_conf {
int next_barrier_nr;
struct hlist_head *app_reads_hash; /* is proteced by req_lock */
struct list_head resync_reads;
atomic_t pp_in_use;
atomic_t pp_in_use; /* allocated from page pool */
atomic_t pp_in_use_by_net; /* sendpage()d, still referenced by tcp */
wait_queue_head_t ee_wait;
struct page *md_io_page; /* one page buffer for md_io */
struct page *md_io_tmpp; /* for logical_block_size != 512 */
@ -1555,7 +1556,10 @@ extern struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev,
sector_t sector,
unsigned int data_size,
gfp_t gfp_mask) __must_hold(local);
extern void drbd_free_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e);
extern void drbd_free_some_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e,
int is_net);
#define drbd_free_ee(m,e) drbd_free_some_ee(m, e, 0)
#define drbd_free_net_ee(m,e) drbd_free_some_ee(m, e, 1)
extern void drbd_wait_ee_list_empty(struct drbd_conf *mdev,
struct list_head *head);
extern void _drbd_wait_ee_list_empty(struct drbd_conf *mdev,

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@ -2753,6 +2753,7 @@ void drbd_init_set_defaults(struct drbd_conf *mdev)
atomic_set(&mdev->net_cnt, 0);
atomic_set(&mdev->packet_seq, 0);
atomic_set(&mdev->pp_in_use, 0);
atomic_set(&mdev->pp_in_use_by_net, 0);
atomic_set(&mdev->rs_sect_in, 0);
atomic_set(&mdev->rs_sect_ev, 0);

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@ -241,7 +241,7 @@ static void drbd_kick_lo_and_reclaim_net(struct drbd_conf *mdev)
spin_unlock_irq(&mdev->req_lock);
list_for_each_entry_safe(e, t, &reclaimed, w.list)
drbd_free_ee(mdev, e);
drbd_free_net_ee(mdev, e);
}
/**
@ -298,9 +298,11 @@ static struct page *drbd_pp_alloc(struct drbd_conf *mdev, unsigned number, bool
* Is also used from inside an other spin_lock_irq(&mdev->req_lock);
* Either links the page chain back to the global pool,
* or returns all pages to the system. */
static void drbd_pp_free(struct drbd_conf *mdev, struct page *page)
static void drbd_pp_free(struct drbd_conf *mdev, struct page *page, int is_net)
{
atomic_t *a = is_net ? &mdev->pp_in_use_by_net : &mdev->pp_in_use;
int i;
if (drbd_pp_vacant > (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE)*minor_count)
i = page_chain_free(page);
else {
@ -311,10 +313,10 @@ static void drbd_pp_free(struct drbd_conf *mdev, struct page *page)
drbd_pp_vacant += i;
spin_unlock(&drbd_pp_lock);
}
atomic_sub(i, &mdev->pp_in_use);
i = atomic_read(&mdev->pp_in_use);
i = atomic_sub_return(i, a);
if (i < 0)
dev_warn(DEV, "ASSERTION FAILED: pp_in_use: %d < 0\n", i);
dev_warn(DEV, "ASSERTION FAILED: %s: %d < 0\n",
is_net ? "pp_in_use_by_net" : "pp_in_use", i);
wake_up(&drbd_pp_wait);
}
@ -374,11 +376,11 @@ struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev,
return NULL;
}
void drbd_free_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e)
void drbd_free_some_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e, int is_net)
{
if (e->flags & EE_HAS_DIGEST)
kfree(e->digest);
drbd_pp_free(mdev, e->pages);
drbd_pp_free(mdev, e->pages, is_net);
D_ASSERT(atomic_read(&e->pending_bios) == 0);
D_ASSERT(hlist_unhashed(&e->colision));
mempool_free(e, drbd_ee_mempool);
@ -389,13 +391,14 @@ int drbd_release_ee(struct drbd_conf *mdev, struct list_head *list)
LIST_HEAD(work_list);
struct drbd_epoch_entry *e, *t;
int count = 0;
int is_net = list == &mdev->net_ee;
spin_lock_irq(&mdev->req_lock);
list_splice_init(list, &work_list);
spin_unlock_irq(&mdev->req_lock);
list_for_each_entry_safe(e, t, &work_list, w.list) {
drbd_free_ee(mdev, e);
drbd_free_some_ee(mdev, e, is_net);
count++;
}
return count;
@ -424,7 +427,7 @@ static int drbd_process_done_ee(struct drbd_conf *mdev)
spin_unlock_irq(&mdev->req_lock);
list_for_each_entry_safe(e, t, &reclaimed, w.list)
drbd_free_ee(mdev, e);
drbd_free_net_ee(mdev, e);
/* possible callbacks here:
* e_end_block, and e_end_resync_block, e_send_discard_ack.
@ -1460,7 +1463,7 @@ static int drbd_drain_block(struct drbd_conf *mdev, int data_size)
data_size -= rr;
}
kunmap(page);
drbd_pp_free(mdev, page);
drbd_pp_free(mdev, page, 0);
return rv;
}
@ -3879,6 +3882,9 @@ static void drbd_disconnect(struct drbd_conf *mdev)
i = drbd_release_ee(mdev, &mdev->net_ee);
if (i)
dev_info(DEV, "net_ee not empty, killed %u entries\n", i);
i = atomic_read(&mdev->pp_in_use_by_net);
if (i)
dev_info(DEV, "pp_in_use_by_net = %d, expected 0\n", i);
i = atomic_read(&mdev->pp_in_use);
if (i)
dev_info(DEV, "pp_in_use = %d, expected 0\n", i);

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@ -914,9 +914,13 @@ static void move_to_net_ee_or_free(struct drbd_conf *mdev, struct drbd_epoch_ent
{
if (drbd_ee_has_active_page(e)) {
/* This might happen if sendpage() has not finished */
int i = DIV_ROUND_UP(e->size, PAGE_SIZE);
atomic_add(i, &mdev->pp_in_use_by_net);
atomic_sub(i, &mdev->pp_in_use);
spin_lock_irq(&mdev->req_lock);
list_add_tail(&e->w.list, &mdev->net_ee);
spin_unlock_irq(&mdev->req_lock);
wake_up(&drbd_pp_wait);
} else
drbd_free_ee(mdev, e);
}