lru_cache: allow multiple changes per transaction
Allow multiple changes to the active set of elements in lru_cache.
The only current user of lru_cache, drbd, is driving this generalisation.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c
index 1ce3de6..44097c8 100644
--- a/drivers/block/drbd/drbd_actlog.c
+++ b/drivers/block/drbd/drbd_actlog.c
@@ -175,7 +175,6 @@
{
struct lc_element *al_ext;
struct lc_element *tmp;
- unsigned long al_flags = 0;
int wake;
spin_lock_irq(&mdev->al_lock);
@@ -190,19 +189,8 @@
return NULL;
}
}
- al_ext = lc_get(mdev->act_log, enr);
- al_flags = mdev->act_log->flags;
+ al_ext = lc_get(mdev->act_log, enr);
spin_unlock_irq(&mdev->al_lock);
-
- /*
- if (!al_ext) {
- if (al_flags & LC_STARVING)
- dev_warn(DEV, "Have to wait for LRU element (AL too small?)\n");
- if (al_flags & LC_DIRTY)
- dev_warn(DEV, "Ongoing AL update (AL device too slow?)\n");
- }
- */
-
return al_ext;
}
@@ -235,7 +223,7 @@
mdev->al_writ_cnt++;
spin_lock_irq(&mdev->al_lock);
- lc_changed(mdev->act_log, al_ext);
+ lc_committed(mdev->act_log);
spin_unlock_irq(&mdev->al_lock);
wake_up(&mdev->al_wait);
}
@@ -601,7 +589,7 @@
struct lc_element *al_ext;
int i;
- D_ASSERT(test_bit(__LC_DIRTY, &mdev->act_log->flags));
+ D_ASSERT(test_bit(__LC_LOCKED, &mdev->act_log->flags));
for (i = 0; i < mdev->act_log->nr_elements; i++) {
al_ext = lc_element_by_index(mdev->act_log, i);
@@ -708,7 +696,9 @@
}
ext->rs_left = rs_left;
ext->rs_failed = success ? 0 : count;
- lc_changed(mdev->resync, &ext->lce);
+ /* we don't keep a persistent log of the resync lru,
+ * we can commit any change right away. */
+ lc_committed(mdev->resync);
}
lc_put(mdev->resync, &ext->lce);
/* no race, we are within the al_lock! */
@@ -892,7 +882,7 @@
if (bm_ext->lce.lc_number != enr) {
bm_ext->rs_left = drbd_bm_e_weight(mdev, enr);
bm_ext->rs_failed = 0;
- lc_changed(mdev->resync, &bm_ext->lce);
+ lc_committed(mdev->resync);
wakeup = 1;
}
if (bm_ext->lce.refcnt == 1)
@@ -908,7 +898,7 @@
if (rs_flags & LC_STARVING)
dev_warn(DEV, "Have to wait for element"
" (resync LRU too small?)\n");
- BUG_ON(rs_flags & LC_DIRTY);
+ BUG_ON(rs_flags & LC_LOCKED);
}
return bm_ext;
@@ -916,26 +906,12 @@
static int _is_in_al(struct drbd_conf *mdev, unsigned int enr)
{
- struct lc_element *al_ext;
- int rv = 0;
+ int rv;
spin_lock_irq(&mdev->al_lock);
- if (unlikely(enr == mdev->act_log->new_number))
- rv = 1;
- else {
- al_ext = lc_find(mdev->act_log, enr);
- if (al_ext) {
- if (al_ext->refcnt)
- rv = 1;
- }
- }
+ rv = lc_is_used(mdev->act_log, enr);
spin_unlock_irq(&mdev->al_lock);
- /*
- if (unlikely(rv)) {
- dev_info(DEV, "Delaying sync read until app's write is done\n");
- }
- */
return rv;
}
@@ -1065,13 +1041,13 @@
if (rs_flags & LC_STARVING)
dev_warn(DEV, "Have to wait for element"
" (resync LRU too small?)\n");
- BUG_ON(rs_flags & LC_DIRTY);
+ BUG_ON(rs_flags & LC_LOCKED);
goto try_again;
}
if (bm_ext->lce.lc_number != enr) {
bm_ext->rs_left = drbd_bm_e_weight(mdev, enr);
bm_ext->rs_failed = 0;
- lc_changed(mdev->resync, &bm_ext->lce);
+ lc_committed(mdev->resync);
wake_up(&mdev->al_wait);
D_ASSERT(test_bit(BME_LOCKED, &bm_ext->flags) == 0);
}
@@ -1082,8 +1058,6 @@
}
check_al:
for (i = 0; i < AL_EXT_PER_BM_SECT; i++) {
- if (unlikely(al_enr+i == mdev->act_log->new_number))
- goto try_again;
if (lc_is_used(mdev->act_log, al_enr+i))
goto try_again;
}
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index ae8f42e..0a92f52 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -760,7 +760,7 @@
in_use = 0;
t = mdev->act_log;
- n = lc_create("act_log", drbd_al_ext_cache,
+ n = lc_create("act_log", drbd_al_ext_cache, 1,
mdev->sync_conf.al_extents, sizeof(struct lc_element), 0);
if (n == NULL) {
@@ -1016,7 +1016,7 @@
}
resync_lru = lc_create("resync", drbd_bm_ext_cache,
- 61, sizeof(struct bm_extent),
+ 1, 61, sizeof(struct bm_extent),
offsetof(struct bm_extent, lce));
if (!resync_lru) {
retcode = ERR_NOMEM;
