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authorLinus Torvalds <torvalds@linux-foundation.org>2018-01-31 14:31:10 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2018-01-31 14:31:10 -0800
commitb2fe5fa68642860e7de76167c3111623aa0d5de1 (patch)
treeb7f9b89b7039ecefbc35fe3c8e73a6ff972641dd /lib/rhashtable.c
parenta103950e0dd2058df5e8a8d4a915707bdcf205f0 (diff)
parenta54667f6728c2714a400f3c884727da74b6d1717 (diff)
downloadop-kernel-dev-b2fe5fa68642860e7de76167c3111623aa0d5de1.zip
op-kernel-dev-b2fe5fa68642860e7de76167c3111623aa0d5de1.tar.gz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: 1) Significantly shrink the core networking routing structures. Result of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf 2) Add netdevsim driver for testing various offloads, from Jakub Kicinski. 3) Support cross-chip FDB operations in DSA, from Vivien Didelot. 4) Add a 2nd listener hash table for TCP, similar to what was done for UDP. From Martin KaFai Lau. 5) Add eBPF based queue selection to tun, from Jason Wang. 6) Lockless qdisc support, from John Fastabend. 7) SCTP stream interleave support, from Xin Long. 8) Smoother TCP receive autotuning, from Eric Dumazet. 9) Lots of erspan tunneling enhancements, from William Tu. 10) Add true function call support to BPF, from Alexei Starovoitov. 11) Add explicit support for GRO HW offloading, from Michael Chan. 12) Support extack generation in more netlink subsystems. From Alexander Aring, Quentin Monnet, and Jakub Kicinski. 13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From Russell King. 14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso. 15) Many improvements and simplifications to the NFP driver bpf JIT, from Jakub Kicinski. 16) Support for ipv6 non-equal cost multipath routing, from Ido Schimmel. 17) Add resource abstration to devlink, from Arkadi Sharshevsky. 18) Packet scheduler classifier shared filter block support, from Jiri Pirko. 19) Avoid locking in act_csum, from Davide Caratti. 20) devinet_ioctl() simplifications from Al viro. 21) More TCP bpf improvements from Lawrence Brakmo. 22) Add support for onlink ipv6 route flag, similar to ipv4, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits) tls: Add support for encryption using async offload accelerator ip6mr: fix stale iterator net/sched: kconfig: Remove blank help texts openvswitch: meter: Use 64-bit arithmetic instead of 32-bit tcp_nv: fix potential integer overflow in tcpnv_acked r8169: fix RTL8168EP take too long to complete driver initialization. qmi_wwan: Add support for Quectel EP06 rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK ipmr: Fix ptrdiff_t print formatting ibmvnic: Wait for device response when changing MAC qlcnic: fix deadlock bug tcp: release sk_frag.page in tcp_disconnect ipv4: Get the address of interface correctly. net_sched: gen_estimator: fix lockdep splat net: macb: Handle HRESP error net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring ipv6: addrconf: break critical section in addrconf_verify_rtnl() ipv6: change route cache aging logic i40e/i40evf: Update DESC_NEEDED value to reflect larger value bnxt_en: cleanup DIM work on device shutdown ...
Diffstat (limited to 'lib/rhashtable.c')
-rw-r--r--lib/rhashtable.c160
1 files changed, 102 insertions, 58 deletions
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index ddd7dde..3825c30 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -65,42 +65,6 @@ EXPORT_SYMBOL_GPL(lockdep_rht_bucket_is_held);
#define ASSERT_RHT_MUTEX(HT)
#endif
-
-static int alloc_bucket_locks(struct rhashtable *ht, struct bucket_table *tbl,
- gfp_t gfp)
-{
- unsigned int i, size;
-#if defined(CONFIG_PROVE_LOCKING)
- unsigned int nr_pcpus = 2;
-#else
- unsigned int nr_pcpus = num_possible_cpus();
-#endif
-
- nr_pcpus = min_t(unsigned int, nr_pcpus, 64UL);
- size = roundup_pow_of_two(nr_pcpus * ht->p.locks_mul);
-
- /* Never allocate more than 0.5 locks per bucket */
- size = min_t(unsigned int, size, tbl->size >> 1);
-
- if (tbl->nest)
- size = min(size, 1U << tbl->nest);
-
- if (sizeof(spinlock_t) != 0) {
- if (gfpflags_allow_blocking(gfp))
- tbl->locks = kvmalloc(size * sizeof(spinlock_t), gfp);
- else
- tbl->locks = kmalloc_array(size, sizeof(spinlock_t),
- gfp);
- if (!tbl->locks)
- return -ENOMEM;
- for (i = 0; i < size; i++)
- spin_lock_init(&tbl->locks[i]);
- }
- tbl->locks_mask = size - 1;
-
- return 0;
-}
-
static void nested_table_free(union nested_table *ntbl, unsigned int size)
{
const unsigned int shift = PAGE_SHIFT - ilog2(sizeof(void *));
@@ -140,7 +104,7 @@ static void bucket_table_free(const struct bucket_table *tbl)
if (tbl->nest)
nested_bucket_table_free(tbl);
- kvfree(tbl->locks);
+ free_bucket_spinlocks(tbl->locks);
kvfree(tbl);
}
@@ -207,7 +171,7 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht,
gfp_t gfp)
{
struct bucket_table *tbl = NULL;
- size_t size;
+ size_t size, max_locks;
int i;
size = sizeof(*tbl) + nbuckets * sizeof(tbl->buckets[0]);
@@ -227,7 +191,12 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht,
tbl->size = size;
- if (alloc_bucket_locks(ht, tbl, gfp) < 0) {
+ max_locks = size >> 1;
+ if (tbl->nest)
+ max_locks = min_t(size_t, max_locks, 1U << tbl->nest);
+
+ if (alloc_bucket_spinlocks(&tbl->locks, &tbl->locks_mask, max_locks,
+ ht->p.locks_mul, gfp) < 0) {
bucket_table_free(tbl);
return NULL;
}
@@ -707,6 +676,7 @@ void rhashtable_walk_enter(struct rhashtable *ht, struct rhashtable_iter *iter)
iter->p = NULL;
iter->slot = 0;
iter->skip = 0;
+ iter->end_of_table = 0;
spin_lock(&ht->lock);
iter->walker.tbl =
@@ -732,7 +702,7 @@ void rhashtable_walk_exit(struct rhashtable_iter *iter)
EXPORT_SYMBOL_GPL(rhashtable_walk_exit);
/**
- * rhashtable_walk_start - Start a hash table walk
+ * rhashtable_walk_start_check - Start a hash table walk
* @iter: Hash table iterator
*
* Start a hash table walk at the current iterator position. Note that we take
@@ -744,8 +714,12 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_exit);
* Returns -EAGAIN if resize event occured. Note that the iterator
* will rewind back to the beginning and you may use it immediately
* by calling rhashtable_walk_next.
+ *
+ * rhashtable_walk_start is defined as an inline variant that returns
+ * void. This is preferred in cases where the caller would ignore
+ * resize events and always continue.
*/
-int rhashtable_walk_start(struct rhashtable_iter *iter)
+int rhashtable_walk_start_check(struct rhashtable_iter *iter)
__acquires(RCU)
{
struct rhashtable *ht = iter->ht;
@@ -757,28 +731,26 @@ int rhashtable_walk_start(struct rhashtable_iter *iter)
list_del(&iter->walker.list);
spin_unlock(&ht->lock);
- if (!iter->walker.tbl) {
+ if (!iter->walker.tbl && !iter->end_of_table) {
iter->walker.tbl = rht_dereference_rcu(ht->tbl, ht);
return -EAGAIN;
}
return 0;
}
-EXPORT_SYMBOL_GPL(rhashtable_walk_start);
+EXPORT_SYMBOL_GPL(rhashtable_walk_start_check);
/**
- * rhashtable_walk_next - Return the next object and advance the iterator
- * @iter: Hash table iterator
+ * __rhashtable_walk_find_next - Find the next element in a table (or the first
+ * one in case of a new walk).
*
- * Note that you must call rhashtable_walk_stop when you are finished
- * with the walk.
+ * @iter: Hash table iterator
*
- * Returns the next object or NULL when the end of the table is reached.
+ * Returns the found object or NULL when the end of the table is reached.
*
- * Returns -EAGAIN if resize event occured. Note that the iterator
- * will rewind back to the beginning and you may continue to use it.
+ * Returns -EAGAIN if resize event occurred.
*/
-void *rhashtable_walk_next(struct rhashtable_iter *iter)
+static void *__rhashtable_walk_find_next(struct rhashtable_iter *iter)
{
struct bucket_table *tbl = iter->walker.tbl;
struct rhlist_head *list = iter->list;
@@ -786,13 +758,8 @@ void *rhashtable_walk_next(struct rhashtable_iter *iter)
struct rhash_head *p = iter->p;
bool rhlist = ht->rhlist;
- if (p) {
- if (!rhlist || !(list = rcu_dereference(list->next))) {
- p = rcu_dereference(p->next);
- list = container_of(p, struct rhlist_head, rhead);
- }
- goto next;
- }
+ if (!tbl)
+ return NULL;
for (; iter->slot < tbl->size; iter->slot++) {
int skip = iter->skip;
@@ -836,13 +803,90 @@ next:
iter->slot = 0;
iter->skip = 0;
return ERR_PTR(-EAGAIN);
+ } else {
+ iter->end_of_table = true;
}
return NULL;
}
+
+/**
+ * rhashtable_walk_next - Return the next object and advance the iterator
+ * @iter: Hash table iterator
+ *
+ * Note that you must call rhashtable_walk_stop when you are finished
+ * with the walk.
+ *
+ * Returns the next object or NULL when the end of the table is reached.
+ *
+ * Returns -EAGAIN if resize event occurred. Note that the iterator
+ * will rewind back to the beginning and you may continue to use it.
+ */
+void *rhashtable_walk_next(struct rhashtable_iter *iter)
+{
+ struct rhlist_head *list = iter->list;
+ struct rhashtable *ht = iter->ht;
+ struct rhash_head *p = iter->p;
+ bool rhlist = ht->rhlist;
+
+ if (p) {
+ if (!rhlist || !(list = rcu_dereference(list->next))) {
+ p = rcu_dereference(p->next);
+ list = container_of(p, struct rhlist_head, rhead);
+ }
+ if (!rht_is_a_nulls(p)) {
+ iter->skip++;
+ iter->p = p;
+ iter->list = list;
+ return rht_obj(ht, rhlist ? &list->rhead : p);
+ }
+
+ /* At the end of this slot, switch to next one and then find
+ * next entry from that point.
+ */
+ iter->skip = 0;
+ iter->slot++;
+ }
+
+ return __rhashtable_walk_find_next(iter);
+}
EXPORT_SYMBOL_GPL(rhashtable_walk_next);
/**
+ * rhashtable_walk_peek - Return the next object but don't advance the iterator
+ * @iter: Hash table iterator
+ *
+ * Returns the next object or NULL when the end of the table is reached.
+ *
+ * Returns -EAGAIN if resize event occurred. Note that the iterator
+ * will rewind back to the beginning and you may continue to use it.
+ */
+void *rhashtable_walk_peek(struct rhashtable_iter *iter)
+{
+ struct rhlist_head *list = iter->list;
+ struct rhashtable *ht = iter->ht;
+ struct rhash_head *p = iter->p;
+
+ if (p)
+ return rht_obj(ht, ht->rhlist ? &list->rhead : p);
+
+ /* No object found in current iter, find next one in the table. */
+
+ if (iter->skip) {
+ /* A nonzero skip value points to the next entry in the table
+ * beyond that last one that was found. Decrement skip so
+ * we find the current value. __rhashtable_walk_find_next
+ * will restore the original value of skip assuming that
+ * the table hasn't changed.
+ */
+ iter->skip--;
+ }
+
+ return __rhashtable_walk_find_next(iter);
+}
+EXPORT_SYMBOL_GPL(rhashtable_walk_peek);
+
+/**
* rhashtable_walk_stop - Finish a hash table walk
* @iter: Hash table iterator
*
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