diff options
author | Rodrigo Vivi <[email protected]> | 2018-07-23 09:13:12 -0700 |
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committer | Rodrigo Vivi <[email protected]> | 2018-07-23 09:13:12 -0700 |
commit | c74a7469f97c0f40b46e82ee979f9fb1bb6e847c (patch) | |
tree | f2690a1a916b73ef94657fbf0e0141ae57701825 /lib/rhashtable.c | |
parent | 6f15a7de86c8cf2dc09fc9e6d07047efa40ef809 (diff) | |
parent | 500775074f88d9cf5416bed2ca19592812d62c41 (diff) |
Merge drm/drm-next into drm-intel-next-queued
We need a backmerge to get DP_DPCD_REV_14 before we push other
i915 changes to dinq that could break compilation.
Signed-off-by: Rodrigo Vivi <[email protected]>
Diffstat (limited to 'lib/rhashtable.c')
-rw-r--r-- | lib/rhashtable.c | 51 |
1 files changed, 46 insertions, 5 deletions
diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 2b2b79974b61..9427b5766134 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -668,8 +668,9 @@ EXPORT_SYMBOL_GPL(rhashtable_insert_slow); * For a completely stable walk you should construct your own data * structure outside the hash table. * - * This function may sleep so you must not call it from interrupt - * context or with spin locks held. + * This function may be called from any process context, including + * non-preemptable context, but cannot be called from softirq or + * hardirq context. * * You must call rhashtable_walk_exit after this function returns. */ @@ -726,6 +727,7 @@ int rhashtable_walk_start_check(struct rhashtable_iter *iter) __acquires(RCU) { struct rhashtable *ht = iter->ht; + bool rhlist = ht->rhlist; rcu_read_lock(); @@ -734,11 +736,52 @@ int rhashtable_walk_start_check(struct rhashtable_iter *iter) list_del(&iter->walker.list); spin_unlock(&ht->lock); - if (!iter->walker.tbl && !iter->end_of_table) { + if (iter->end_of_table) + return 0; + if (!iter->walker.tbl) { iter->walker.tbl = rht_dereference_rcu(ht->tbl, ht); + iter->slot = 0; + iter->skip = 0; return -EAGAIN; } + if (iter->p && !rhlist) { + /* + * We need to validate that 'p' is still in the table, and + * if so, update 'skip' + */ + struct rhash_head *p; + int skip = 0; + rht_for_each_rcu(p, iter->walker.tbl, iter->slot) { + skip++; + if (p == iter->p) { + iter->skip = skip; + goto found; + } + } + iter->p = NULL; + } else if (iter->p && rhlist) { + /* Need to validate that 'list' is still in the table, and + * if so, update 'skip' and 'p'. + */ + struct rhash_head *p; + struct rhlist_head *list; + int skip = 0; + rht_for_each_rcu(p, iter->walker.tbl, iter->slot) { + for (list = container_of(p, struct rhlist_head, rhead); + list; + list = rcu_dereference(list->next)) { + skip++; + if (list == iter->list) { + iter->p = p; + skip = skip; + goto found; + } + } + } + iter->p = NULL; + } +found: return 0; } EXPORT_SYMBOL_GPL(rhashtable_walk_start_check); @@ -914,8 +957,6 @@ void rhashtable_walk_stop(struct rhashtable_iter *iter) iter->walker.tbl = NULL; spin_unlock(&ht->lock); - iter->p = NULL; - out: rcu_read_unlock(); } |