In certain cases, the 802.11 mesh pathtable code wants to
iterate over all of the entries in the forwarding table from
the receive path, which is inside an RCU read-side critical
section. Enable walks inside atomic sections by allowing
GFP_ATOMIC allocations for the walker state.
Change all existing callsites to pass in GFP_KERNEL.
Cc: Thomas Graf <[email protected]>
Cc: [email protected]
Signed-off-by: Bob Copeland <[email protected]>
---
include/linux/rhashtable.h | 3 ++-
lib/rhashtable.c | 6 ++++--
net/ipv6/ila/ila_xlat.c | 3 ++-
net/netfilter/nft_hash.c | 4 ++--
net/netlink/af_netlink.c | 3 ++-
net/sctp/proc.c | 3 ++-
6 files changed, 14 insertions(+), 8 deletions(-)
diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h
index 63bd7601b6de..3eef0802a0cd 100644
--- a/include/linux/rhashtable.h
+++ b/include/linux/rhashtable.h
@@ -346,7 +346,8 @@ struct bucket_table *rhashtable_insert_slow(struct rhashtable *ht,
struct bucket_table *old_tbl);
int rhashtable_insert_rehash(struct rhashtable *ht, struct bucket_table *tbl);
-int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter);
+int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter,
+ gfp_t gfp);
void rhashtable_walk_exit(struct rhashtable_iter *iter);
int rhashtable_walk_start(struct rhashtable_iter *iter) __acquires(RCU);
void *rhashtable_walk_next(struct rhashtable_iter *iter);
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index cc808707d1cf..5d845ffd7982 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -487,6 +487,7 @@ EXPORT_SYMBOL_GPL(rhashtable_insert_slow);
* rhashtable_walk_init - Initialise an iterator
* @ht: Table to walk over
* @iter: Hash table Iterator
+ * @gfp: GFP flags for allocations
*
* This function prepares a hash table walk.
*
@@ -504,14 +505,15 @@ EXPORT_SYMBOL_GPL(rhashtable_insert_slow);
* You must call rhashtable_walk_exit if this function returns
* successfully.
*/
-int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter)
+int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter,
+ gfp_t gfp)
{
iter->ht = ht;
iter->p = NULL;
iter->slot = 0;
iter->skip = 0;
- iter->walker = kmalloc(sizeof(*iter->walker), GFP_KERNEL);
+ iter->walker = kmalloc(sizeof(*iter->walker), gfp);
if (!iter->walker)
return -ENOMEM;
diff --git a/net/ipv6/ila/ila_xlat.c b/net/ipv6/ila/ila_xlat.c
index 295ca29a23c3..0b03533453e4 100644
--- a/net/ipv6/ila/ila_xlat.c
+++ b/net/ipv6/ila/ila_xlat.c
@@ -501,7 +501,8 @@ static int ila_nl_dump_start(struct netlink_callback *cb)
struct ila_net *ilan = net_generic(net, ila_net_id);
struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args;
- return rhashtable_walk_init(&ilan->rhash_table, &iter->rhiter);
+ return rhashtable_walk_init(&ilan->rhash_table, &iter->rhiter,
+ GFP_KERNEL);
}
static int ila_nl_dump_done(struct netlink_callback *cb)
diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c
index 3f9d45d3d9b7..6fa016564f90 100644
--- a/net/netfilter/nft_hash.c
+++ b/net/netfilter/nft_hash.c
@@ -192,7 +192,7 @@ static void nft_hash_walk(const struct nft_ctx *ctx, const struct nft_set *set,
u8 genmask = nft_genmask_cur(read_pnet(&set->pnet));
int err;
- err = rhashtable_walk_init(&priv->ht, &hti);
+ err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
iter->err = err;
if (err)
return;
@@ -248,7 +248,7 @@ static void nft_hash_gc(struct work_struct *work)
priv = container_of(work, struct nft_hash, gc_work.work);
set = nft_set_container_of(priv);
- err = rhashtable_walk_init(&priv->ht, &hti);
+ err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
if (err)
goto schedule;
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index c8416792cce0..6e0cbdeb21d3 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -2335,7 +2335,8 @@ static int netlink_walk_start(struct nl_seq_iter *iter)
{
int err;
- err = rhashtable_walk_init(&nl_table[iter->link].hash, &iter->hti);
+ err = rhashtable_walk_init(&nl_table[iter->link].hash, &iter->hti,
+ GFP_KERNEL);
if (err) {
iter->link = MAX_LINKS;
return err;
diff --git a/net/sctp/proc.c b/net/sctp/proc.c
index cfc3c7101a38..c5991e5e5daf 100644
--- a/net/sctp/proc.c
+++ b/net/sctp/proc.c
@@ -319,7 +319,8 @@ static int sctp_transport_walk_start(struct seq_file *seq)
struct sctp_ht_iter *iter = seq->private;
int err;
- err = rhashtable_walk_init(&sctp_transport_hashtable, &iter->hti);
+ err = rhashtable_walk_init(&sctp_transport_hashtable, &iter->hti,
+ GFP_KERNEL);
if (err)
return err;
--
2.6.1
In the time since the mesh path table was implemented as an
RCU-traversable, dynamically growing hash table, a generic RCU
hashtable implementation was added to the kernel.
Switch the mesh path table over to rhashtable to remove some code
and also gain some features like automatic shrinking.
Cc: Thomas Graf <[email protected]>
Cc: [email protected]
Signed-off-by: Bob Copeland <[email protected]>
---
net/mac80211/ieee80211_i.h | 11 +-
net/mac80211/mesh.c | 6 -
net/mac80211/mesh.h | 31 +-
net/mac80211/mesh_pathtbl.c | 786 ++++++++++++++------------------------------
4 files changed, 259 insertions(+), 575 deletions(-)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 597f1b6260f4..a2857cd6d479 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -697,17 +697,10 @@ struct ieee80211_if_mesh {
/* offset from skb->data while building IE */
int meshconf_offset;
- struct mesh_table __rcu *mesh_paths;
- struct mesh_table __rcu *mpp_paths; /* Store paths for MPP&MAP */
+ struct mesh_table *mesh_paths;
+ struct mesh_table *mpp_paths; /* Store paths for MPP&MAP */
int mesh_paths_generation;
int mpp_paths_generation;
-
- /* Protects assignment of the mesh_paths/mpp_paths table
- * pointer for resize against reading it for add/delete
- * of individual paths. Pure readers (lookups) just use
- * RCU.
- */
- rwlock_t pathtbl_resize_lock;
};
#ifdef CONFIG_MAC80211_MESH
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index c92af2a7714d..a216c439b6f2 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -1347,12 +1347,6 @@ void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
mesh_path_start_discovery(sdata);
- if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
- mesh_mpath_table_grow(sdata);
-
- if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
- mesh_mpp_table_grow(sdata);
-
if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
ieee80211_mesh_housekeeping(sdata);
diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h
index f3cc3917e048..cc6854db156e 100644
--- a/net/mac80211/mesh.h
+++ b/net/mac80211/mesh.h
@@ -51,10 +51,6 @@ enum mesh_path_flags {
*
*
* @MESH_WORK_HOUSEKEEPING: run the periodic mesh housekeeping tasks
- * @MESH_WORK_GROW_MPATH_TABLE: the mesh path table is full and needs
- * to grow.
- * @MESH_WORK_GROW_MPP_TABLE: the mesh portals table is full and needs to
- * grow
* @MESH_WORK_ROOT: the mesh root station needs to send a frame
* @MESH_WORK_DRIFT_ADJUST: time to compensate for clock drift relative to other
* mesh nodes
@@ -62,8 +58,6 @@ enum mesh_path_flags {
*/
enum mesh_deferred_task_flags {
MESH_WORK_HOUSEKEEPING,
- MESH_WORK_GROW_MPATH_TABLE,
- MESH_WORK_GROW_MPP_TABLE,
MESH_WORK_ROOT,
MESH_WORK_DRIFT_ADJUST,
MESH_WORK_MBSS_CHANGED,
@@ -105,6 +99,7 @@ enum mesh_deferred_task_flags {
struct mesh_path {
u8 dst[ETH_ALEN];
u8 mpp[ETH_ALEN]; /* used for MPP or MAP */
+ struct rhash_head rhash;
struct hlist_node gate_list;
struct ieee80211_sub_if_data *sdata;
struct sta_info __rcu *next_hop;
@@ -129,34 +124,17 @@ struct mesh_path {
/**
* struct mesh_table
*
- * @hash_buckets: array of hash buckets of the table
- * @hashwlock: array of locks to protect write operations, one per bucket
- * @hash_mask: 2^size_order - 1, used to compute hash idx
- * @hash_rnd: random value used for hash computations
* @entries: number of entries in the table
- * @free_node: function to free nodes of the table
- * @copy_node: function to copy nodes of the table
- * @size_order: determines size of the table, there will be 2^size_order hash
- * buckets
* @known_gates: list of known mesh gates and their mpaths by the station. The
* gate's mpath may or may not be resolved and active.
- *
- * rcu_head: RCU head to free the table
+ * @rhash: the rhashtable containing struct mesh_paths, keyed by dest addr
*/
struct mesh_table {
- /* Number of buckets will be 2^N */
- struct hlist_head *hash_buckets;
- spinlock_t *hashwlock; /* One per bucket, for add/del */
- unsigned int hash_mask; /* (2^size_order) - 1 */
- __u32 hash_rnd; /* Used for hash generation */
atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */
- void (*free_node) (struct hlist_node *p, bool free_leafs);
- int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl);
- int size_order;
struct hlist_head *known_gates;
spinlock_t gates_lock;
- struct rcu_head rcu_head;
+ struct rhashtable rhead;
};
/* Recent multicast cache */
@@ -300,9 +278,6 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
void mesh_sta_cleanup(struct sta_info *sta);
/* Private interfaces */
-/* Mesh tables */
-void mesh_mpath_table_grow(struct ieee80211_sub_if_data *sdata);
-void mesh_mpp_table_grow(struct ieee80211_sub_if_data *sdata);
/* Mesh paths */
int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
u8 ttl, const u8 *target, u32 target_sn,
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index e4daf4b94eaf..7455397f8c3b 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -18,11 +18,20 @@
#include "ieee80211_i.h"
#include "mesh.h"
-/* There will be initially 2^INIT_PATHS_SIZE_ORDER buckets */
-#define INIT_PATHS_SIZE_ORDER 2
+static u32 mesh_table_hash(const void *addr, u32 len, u32 seed)
+{
+ /* Use last four bytes of hw addr as hash index */
+ return jhash_1word(*(u32 *)(addr+2), seed);
+}
-/* Keep the mean chain length below this constant */
-#define MEAN_CHAIN_LEN 2
+static const struct rhashtable_params mesh_rht_params = {
+ .nelem_hint = 2,
+ .automatic_shrinking = true,
+ .key_len = ETH_ALEN,
+ .key_offset = offsetof(struct mesh_path, dst),
+ .head_offset = offsetof(struct mesh_path, rhash),
+ .hashfn = mesh_table_hash,
+};
static inline bool mpath_expired(struct mesh_path *mpath)
{
@@ -31,157 +40,47 @@ static inline bool mpath_expired(struct mesh_path *mpath)
!(mpath->flags & MESH_PATH_FIXED);
}
-struct mpath_node {
- struct hlist_node list;
- struct rcu_head rcu;
- /* This indirection allows two different tables to point to the same
- * mesh_path structure, useful when resizing
- */
- struct mesh_path *mpath;
-};
-
-static inline struct mesh_table *resize_dereference_paths(
- struct ieee80211_sub_if_data *sdata,
- struct mesh_table __rcu *table)
+static void mesh_path_reclaim(struct rcu_head *rp)
{
- return rcu_dereference_protected(table,
- lockdep_is_held(&sdata->u.mesh.pathtbl_resize_lock));
-}
+ struct mesh_path *mpath = container_of(rp, struct mesh_path, rcu);
-static inline struct mesh_table *resize_dereference_mesh_paths(
- struct ieee80211_sub_if_data *sdata)
-{
- return resize_dereference_paths(sdata, sdata->u.mesh.mesh_paths);
+ del_timer_sync(&mpath->timer);
+ kfree(mpath);
}
-static inline struct mesh_table *resize_dereference_mpp_paths(
- struct ieee80211_sub_if_data *sdata)
+static void mesh_path_rht_free(void *ptr, void *unused_arg)
{
- return resize_dereference_paths(sdata, sdata->u.mesh.mpp_paths);
+ struct mesh_path *mpath = ptr;
+ call_rcu(&mpath->rcu, mesh_path_reclaim);
}
-/*
- * CAREFUL -- "tbl" must not be an expression,
- * in particular not an rcu_dereference(), since
- * it's used twice. So it is illegal to do
- * for_each_mesh_entry(rcu_dereference(...), ...)
- */
-#define for_each_mesh_entry(tbl, node, i) \
- for (i = 0; i <= tbl->hash_mask; i++) \
- hlist_for_each_entry_rcu(node, &tbl->hash_buckets[i], list)
-
-
-static struct mesh_table *mesh_table_alloc(int size_order)
+static struct mesh_table *mesh_table_alloc(void)
{
- int i;
struct mesh_table *newtbl;
newtbl = kmalloc(sizeof(struct mesh_table), GFP_ATOMIC);
if (!newtbl)
return NULL;
- newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) *
- (1 << size_order), GFP_ATOMIC);
-
- if (!newtbl->hash_buckets) {
+ newtbl->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
+ if (!newtbl->known_gates) {
kfree(newtbl);
return NULL;
}
-
- newtbl->hashwlock = kmalloc(sizeof(spinlock_t) *
- (1 << size_order), GFP_ATOMIC);
- if (!newtbl->hashwlock) {
- kfree(newtbl->hash_buckets);
- kfree(newtbl);
- return NULL;
- }
-
- newtbl->size_order = size_order;
- newtbl->hash_mask = (1 << size_order) - 1;
+ INIT_HLIST_HEAD(newtbl->known_gates);
atomic_set(&newtbl->entries, 0);
- get_random_bytes(&newtbl->hash_rnd,
- sizeof(newtbl->hash_rnd));
- for (i = 0; i <= newtbl->hash_mask; i++)
- spin_lock_init(&newtbl->hashwlock[i]);
spin_lock_init(&newtbl->gates_lock);
return newtbl;
}
-static void __mesh_table_free(struct mesh_table *tbl)
+static void mesh_table_free(struct mesh_table *tbl)
{
- kfree(tbl->hash_buckets);
- kfree(tbl->hashwlock);
+ rhashtable_free_and_destroy(&tbl->rhead,
+ mesh_path_rht_free, NULL);
kfree(tbl);
}
-static void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
-{
- struct hlist_head *mesh_hash;
- struct hlist_node *p, *q;
- struct mesh_path *gate;
- int i;
-
- mesh_hash = tbl->hash_buckets;
- if (free_leafs) {
- spin_lock_bh(&tbl->gates_lock);
- hlist_for_each_entry_safe(gate, q,
- tbl->known_gates, gate_list)
- hlist_del(&gate->gate_list);
- kfree(tbl->known_gates);
- spin_unlock_bh(&tbl->gates_lock);
- }
- for (i = 0; i <= tbl->hash_mask; i++) {
- spin_lock_bh(&tbl->hashwlock[i]);
- hlist_for_each_safe(p, q, &mesh_hash[i]) {
- tbl->free_node(p, free_leafs);
- atomic_dec(&tbl->entries);
- }
- spin_unlock_bh(&tbl->hashwlock[i]);
- }
-
- __mesh_table_free(tbl);
-}
-
-static int mesh_table_grow(struct mesh_table *oldtbl,
- struct mesh_table *newtbl)
-{
- struct hlist_head *oldhash;
- struct hlist_node *p, *q;
- int i;
-
- if (atomic_read(&oldtbl->entries)
- < MEAN_CHAIN_LEN * (oldtbl->hash_mask + 1))
- return -EAGAIN;
-
- newtbl->free_node = oldtbl->free_node;
- newtbl->copy_node = oldtbl->copy_node;
- newtbl->known_gates = oldtbl->known_gates;
- atomic_set(&newtbl->entries, atomic_read(&oldtbl->entries));
-
- oldhash = oldtbl->hash_buckets;
- for (i = 0; i <= oldtbl->hash_mask; i++)
- hlist_for_each(p, &oldhash[i])
- if (oldtbl->copy_node(p, newtbl) < 0)
- goto errcopy;
-
- return 0;
-
-errcopy:
- for (i = 0; i <= newtbl->hash_mask; i++) {
- hlist_for_each_safe(p, q, &newtbl->hash_buckets[i])
- oldtbl->free_node(p, 0);
- }
- return -ENOMEM;
-}
-
-static u32 mesh_table_hash(const u8 *addr, struct mesh_table *tbl)
-{
- /* Use last four bytes of hw addr as hash index */
- return jhash_1word(*(u32 *)(addr+2), tbl->hash_rnd) & tbl->hash_mask;
-}
-
-
/**
*
* mesh_path_assign_nexthop - update mesh path next hop
@@ -324,22 +223,15 @@ static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
struct ieee80211_sub_if_data *sdata)
{
struct mesh_path *mpath;
- struct hlist_head *bucket;
- struct mpath_node *node;
-
- bucket = &tbl->hash_buckets[mesh_table_hash(dst, tbl)];
- hlist_for_each_entry_rcu(node, bucket, list) {
- mpath = node->mpath;
- if (ether_addr_equal(dst, mpath->dst)) {
- if (mpath_expired(mpath)) {
- spin_lock_bh(&mpath->state_lock);
- mpath->flags &= ~MESH_PATH_ACTIVE;
- spin_unlock_bh(&mpath->state_lock);
- }
- return mpath;
- }
+
+ mpath = rhashtable_lookup_fast(&tbl->rhead, dst, mesh_rht_params);
+
+ if (mpath && mpath_expired(mpath)) {
+ spin_lock_bh(&mpath->state_lock);
+ mpath->flags &= ~MESH_PATH_ACTIVE;
+ spin_unlock_bh(&mpath->state_lock);
}
- return NULL;
+ return mpath;
}
/**
@@ -354,17 +246,52 @@ static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
struct mesh_path *
mesh_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
{
- return mpath_lookup(rcu_dereference(sdata->u.mesh.mesh_paths), dst,
- sdata);
+ return mpath_lookup(sdata->u.mesh.mesh_paths, dst, sdata);
}
struct mesh_path *
mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
{
- return mpath_lookup(rcu_dereference(sdata->u.mesh.mpp_paths), dst,
- sdata);
+ return mpath_lookup(sdata->u.mesh.mpp_paths, dst, sdata);
}
+static struct mesh_path *
+__mesh_path_lookup_by_idx(struct mesh_table *tbl, int idx)
+{
+ int i = 0, ret;
+ struct mesh_path *mpath = NULL;
+ struct rhashtable_iter iter;
+
+ ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
+ if (ret)
+ return NULL;
+
+ ret = rhashtable_walk_start(&iter);
+ if (ret && ret != -EAGAIN)
+ goto err;
+
+ while ((mpath = rhashtable_walk_next(&iter))) {
+ if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
+ continue;
+ if (IS_ERR(mpath))
+ break;
+ if (i++ == idx)
+ break;
+ }
+err:
+ rhashtable_walk_stop(&iter);
+ rhashtable_walk_exit(&iter);
+
+ if (IS_ERR(mpath) || !mpath)
+ return NULL;
+
+ if (mpath_expired(mpath)) {
+ spin_lock_bh(&mpath->state_lock);
+ mpath->flags &= ~MESH_PATH_ACTIVE;
+ spin_unlock_bh(&mpath->state_lock);
+ }
+ return mpath;
+}
/**
* mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
@@ -378,23 +305,7 @@ mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
struct mesh_path *
mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
{
- struct mesh_table *tbl = rcu_dereference(sdata->u.mesh.mesh_paths);
- struct mpath_node *node;
- int i;
- int j = 0;
-
- for_each_mesh_entry(tbl, node, i) {
- if (j++ == idx) {
- if (mpath_expired(node->mpath)) {
- spin_lock_bh(&node->mpath->state_lock);
- node->mpath->flags &= ~MESH_PATH_ACTIVE;
- spin_unlock_bh(&node->mpath->state_lock);
- }
- return node->mpath;
- }
- }
-
- return NULL;
+ return __mesh_path_lookup_by_idx(sdata->u.mesh.mesh_paths, idx);
}
/**
@@ -409,17 +320,7 @@ mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
struct mesh_path *
mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
{
- struct mesh_table *tbl = rcu_dereference(sdata->u.mesh.mpp_paths);
- struct mpath_node *node;
- int i;
- int j = 0;
-
- for_each_mesh_entry(tbl, node, i) {
- if (j++ == idx)
- return node->mpath;
- }
-
- return NULL;
+ return __mesh_path_lookup_by_idx(sdata->u.mesh.mpp_paths, idx);
}
/**
@@ -432,7 +333,7 @@ int mesh_path_add_gate(struct mesh_path *mpath)
int err;
rcu_read_lock();
- tbl = rcu_dereference(mpath->sdata->u.mesh.mesh_paths);
+ tbl = mpath->sdata->u.mesh.mesh_paths;
spin_lock_bh(&mpath->state_lock);
if (mpath->is_gate) {
@@ -526,15 +427,9 @@ struct mesh_path *mesh_path_new(struct ieee80211_sub_if_data *sdata,
struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata,
const u8 *dst)
{
- struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
- struct ieee80211_local *local = sdata->local;
struct mesh_table *tbl;
struct mesh_path *mpath, *new_mpath;
- struct mpath_node *node, *new_node;
- struct hlist_head *bucket;
- int grow = 0;
- int err;
- u32 hash_idx;
+ int ret;
if (ether_addr_equal(dst, sdata->vif.addr))
/* never add ourselves as neighbours */
@@ -546,116 +441,44 @@ struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata,
if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
return ERR_PTR(-ENOSPC);
- read_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- tbl = resize_dereference_mesh_paths(sdata);
-
- hash_idx = mesh_table_hash(dst, tbl);
- bucket = &tbl->hash_buckets[hash_idx];
-
- spin_lock(&tbl->hashwlock[hash_idx]);
-
- hlist_for_each_entry(node, bucket, list) {
- mpath = node->mpath;
- if (ether_addr_equal(dst, mpath->dst))
- goto found;
- }
-
- err = -ENOMEM;
new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
if (!new_mpath)
- goto err_path_alloc;
-
- new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
- if (!new_node)
- goto err_node_alloc;
-
- new_node->mpath = new_mpath;
- hlist_add_head_rcu(&new_node->list, bucket);
- if (atomic_inc_return(&tbl->entries) >=
- MEAN_CHAIN_LEN * (tbl->hash_mask + 1))
- grow = 1;
-
- sdata->u.mesh.mesh_paths_generation++;
-
- if (grow) {
- set_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags);
- ieee80211_queue_work(&local->hw, &sdata->work);
- }
- mpath = new_mpath;
-found:
- spin_unlock(&tbl->hashwlock[hash_idx]);
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- return mpath;
-
-err_node_alloc:
- kfree(new_mpath);
-err_path_alloc:
- atomic_dec(&sdata->u.mesh.mpaths);
- spin_unlock(&tbl->hashwlock[hash_idx]);
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- return ERR_PTR(err);
-}
-
-static void mesh_table_free_rcu(struct rcu_head *rcu)
-{
- struct mesh_table *tbl = container_of(rcu, struct mesh_table, rcu_head);
-
- mesh_table_free(tbl, false);
-}
-
-void mesh_mpath_table_grow(struct ieee80211_sub_if_data *sdata)
-{
- struct mesh_table *oldtbl, *newtbl;
+ return ERR_PTR(-ENOMEM);
- write_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- oldtbl = resize_dereference_mesh_paths(sdata);
- newtbl = mesh_table_alloc(oldtbl->size_order + 1);
- if (!newtbl)
- goto out;
- if (mesh_table_grow(oldtbl, newtbl) < 0) {
- __mesh_table_free(newtbl);
- goto out;
- }
- rcu_assign_pointer(sdata->u.mesh.mesh_paths, newtbl);
+ tbl = sdata->u.mesh.mesh_paths;
+ do {
+ ret = rhashtable_lookup_insert_fast(&tbl->rhead,
+ &new_mpath->rhash,
+ mesh_rht_params);
- call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
+ if (ret == -EEXIST)
+ mpath = rhashtable_lookup_fast(&tbl->rhead,
+ dst,
+ mesh_rht_params);
- out:
- write_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
-}
+ } while (unlikely(ret == -EEXIST && !mpath));
-void mesh_mpp_table_grow(struct ieee80211_sub_if_data *sdata)
-{
- struct mesh_table *oldtbl, *newtbl;
+ if (ret && ret != -EEXIST)
+ return ERR_PTR(ret);
- write_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- oldtbl = resize_dereference_mpp_paths(sdata);
- newtbl = mesh_table_alloc(oldtbl->size_order + 1);
- if (!newtbl)
- goto out;
- if (mesh_table_grow(oldtbl, newtbl) < 0) {
- __mesh_table_free(newtbl);
- goto out;
+ /* At this point either new_mpath was added, or we found a
+ * matching entry already in the table; in the latter case
+ * free the unnecessary new entry.
+ */
+ if (ret == -EEXIST) {
+ kfree(new_mpath);
+ new_mpath = mpath;
}
- rcu_assign_pointer(sdata->u.mesh.mpp_paths, newtbl);
- call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
-
- out:
- write_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
+ sdata->u.mesh.mesh_paths_generation++;
+ return new_mpath;
}
int mpp_path_add(struct ieee80211_sub_if_data *sdata,
const u8 *dst, const u8 *mpp)
{
- struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
- struct ieee80211_local *local = sdata->local;
struct mesh_table *tbl;
- struct mesh_path *mpath, *new_mpath;
- struct mpath_node *node, *new_node;
- struct hlist_head *bucket;
- int grow = 0;
- int err = 0;
- u32 hash_idx;
+ struct mesh_path *new_mpath;
+ int ret;
if (ether_addr_equal(dst, sdata->vif.addr))
/* never add ourselves as neighbours */
@@ -664,56 +487,19 @@ int mpp_path_add(struct ieee80211_sub_if_data *sdata,
if (is_multicast_ether_addr(dst))
return -ENOTSUPP;
- err = -ENOMEM;
new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
- if (!new_mpath)
- goto err_path_alloc;
- new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
- if (!new_node)
- goto err_node_alloc;
+ if (!new_mpath)
+ return -ENOMEM;
memcpy(new_mpath->mpp, mpp, ETH_ALEN);
- new_node->mpath = new_mpath;
- read_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- tbl = resize_dereference_mpp_paths(sdata);
-
- hash_idx = mesh_table_hash(dst, tbl);
- bucket = &tbl->hash_buckets[hash_idx];
-
- spin_lock(&tbl->hashwlock[hash_idx]);
-
- err = -EEXIST;
- hlist_for_each_entry(node, bucket, list) {
- mpath = node->mpath;
- if (ether_addr_equal(dst, mpath->dst))
- goto err_exists;
- }
-
- hlist_add_head_rcu(&new_node->list, bucket);
- if (atomic_inc_return(&tbl->entries) >=
- MEAN_CHAIN_LEN * (tbl->hash_mask + 1))
- grow = 1;
-
- spin_unlock(&tbl->hashwlock[hash_idx]);
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
+ tbl = sdata->u.mesh.mpp_paths;
+ ret = rhashtable_lookup_insert_fast(&tbl->rhead,
+ &new_mpath->rhash,
+ mesh_rht_params);
sdata->u.mesh.mpp_paths_generation++;
-
- if (grow) {
- set_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags);
- ieee80211_queue_work(&local->hw, &sdata->work);
- }
- return 0;
-
-err_exists:
- spin_unlock(&tbl->hashwlock[hash_idx]);
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- kfree(new_node);
-err_node_alloc:
- kfree(new_mpath);
-err_path_alloc:
- return err;
+ return ret;
}
@@ -727,17 +513,26 @@ err_path_alloc:
*/
void mesh_plink_broken(struct sta_info *sta)
{
- struct mesh_table *tbl;
+ struct ieee80211_sub_if_data *sdata = sta->sdata;
+ struct mesh_table *tbl = sdata->u.mesh.mesh_paths;
static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
struct mesh_path *mpath;
- struct mpath_node *node;
- struct ieee80211_sub_if_data *sdata = sta->sdata;
- int i;
+ struct rhashtable_iter iter;
+ int ret;
- rcu_read_lock();
- tbl = rcu_dereference(sdata->u.mesh.mesh_paths);
- for_each_mesh_entry(tbl, node, i) {
- mpath = node->mpath;
+ ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
+ if (ret)
+ return;
+
+ ret = rhashtable_walk_start(&iter);
+ if (ret && ret != -EAGAIN)
+ goto out;
+
+ while ((mpath = rhashtable_walk_next(&iter))) {
+ if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
+ continue;
+ if (IS_ERR(mpath))
+ break;
if (rcu_access_pointer(mpath->next_hop) == sta &&
mpath->flags & MESH_PATH_ACTIVE &&
!(mpath->flags & MESH_PATH_FIXED)) {
@@ -751,30 +546,20 @@ void mesh_plink_broken(struct sta_info *sta)
WLAN_REASON_MESH_PATH_DEST_UNREACHABLE, bcast);
}
}
- rcu_read_unlock();
-}
-
-static void mesh_path_node_reclaim(struct rcu_head *rp)
-{
- struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
-
- del_timer_sync(&node->mpath->timer);
- kfree(node->mpath);
- kfree(node);
+out:
+ rhashtable_walk_stop(&iter);
+ rhashtable_walk_exit(&iter);
}
-/* needs to be called with the corresponding hashwlock taken */
-static void __mesh_path_del(struct mesh_table *tbl, struct mpath_node *node)
+static void __mesh_path_del(struct mesh_table *tbl, struct mesh_path *mpath)
{
- struct mesh_path *mpath = node->mpath;
- struct ieee80211_sub_if_data *sdata = node->mpath->sdata;
+ struct ieee80211_sub_if_data *sdata = mpath->sdata;
+ rhashtable_remove_fast(&tbl->rhead, &mpath->rhash, mesh_rht_params);
spin_lock_bh(&mpath->state_lock);
mpath->flags |= MESH_PATH_RESOLVING;
- if (mpath->is_gate)
- mesh_gate_del(tbl, mpath);
- hlist_del_rcu(&node->list);
- call_rcu(&node->rcu, mesh_path_node_reclaim);
+ mesh_gate_del(tbl, mpath);
+ call_rcu(&mpath->rcu, mesh_path_reclaim);
spin_unlock_bh(&mpath->state_lock);
atomic_dec(&sdata->u.mesh.mpaths);
atomic_dec(&tbl->entries);
@@ -794,63 +579,87 @@ static void __mesh_path_del(struct mesh_table *tbl, struct mpath_node *node)
void mesh_path_flush_by_nexthop(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
- struct mesh_table *tbl;
+ struct mesh_table *tbl = sdata->u.mesh.mesh_paths;
struct mesh_path *mpath;
- struct mpath_node *node;
- int i;
+ struct rhashtable_iter iter;
+ int ret;
- rcu_read_lock();
- read_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- tbl = resize_dereference_mesh_paths(sdata);
- for_each_mesh_entry(tbl, node, i) {
- mpath = node->mpath;
- if (rcu_access_pointer(mpath->next_hop) == sta) {
- spin_lock(&tbl->hashwlock[i]);
- __mesh_path_del(tbl, node);
- spin_unlock(&tbl->hashwlock[i]);
- }
+ ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
+ if (ret)
+ return;
+
+ ret = rhashtable_walk_start(&iter);
+ if (ret && ret != -EAGAIN)
+ goto out;
+
+ while ((mpath = rhashtable_walk_next(&iter))) {
+ if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
+ continue;
+ if (IS_ERR(mpath))
+ break;
+
+ if (rcu_access_pointer(mpath->next_hop) == sta)
+ __mesh_path_del(tbl, mpath);
}
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- rcu_read_unlock();
+out:
+ rhashtable_walk_stop(&iter);
+ rhashtable_walk_exit(&iter);
}
static void mpp_flush_by_proxy(struct ieee80211_sub_if_data *sdata,
const u8 *proxy)
{
- struct mesh_table *tbl;
- struct mesh_path *mpp;
- struct mpath_node *node;
- int i;
+ struct mesh_table *tbl = sdata->u.mesh.mpp_paths;
+ struct mesh_path *mpath;
+ struct rhashtable_iter iter;
+ int ret;
- rcu_read_lock();
- read_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- tbl = resize_dereference_mpp_paths(sdata);
- for_each_mesh_entry(tbl, node, i) {
- mpp = node->mpath;
- if (ether_addr_equal(mpp->mpp, proxy)) {
- spin_lock(&tbl->hashwlock[i]);
- __mesh_path_del(tbl, node);
- spin_unlock(&tbl->hashwlock[i]);
- }
+ ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
+ if (ret)
+ return;
+
+ ret = rhashtable_walk_start(&iter);
+ if (ret && ret != -EAGAIN)
+ goto out;
+
+ while ((mpath = rhashtable_walk_next(&iter))) {
+ if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
+ continue;
+ if (IS_ERR(mpath))
+ break;
+
+ if (ether_addr_equal(mpath->mpp, proxy))
+ __mesh_path_del(tbl, mpath);
}
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- rcu_read_unlock();
+out:
+ rhashtable_walk_stop(&iter);
+ rhashtable_walk_exit(&iter);
}
-static void table_flush_by_iface(struct mesh_table *tbl,
- struct ieee80211_sub_if_data *sdata)
+static void table_flush_by_iface(struct mesh_table *tbl)
{
struct mesh_path *mpath;
- struct mpath_node *node;
- int i;
-
- WARN_ON(!rcu_read_lock_held());
- for_each_mesh_entry(tbl, node, i) {
- mpath = node->mpath;
- spin_lock_bh(&tbl->hashwlock[i]);
- __mesh_path_del(tbl, node);
- spin_unlock_bh(&tbl->hashwlock[i]);
+ struct rhashtable_iter iter;
+ int ret;
+
+ ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
+ if (ret)
+ return;
+
+ ret = rhashtable_walk_start(&iter);
+ if (ret && ret != -EAGAIN)
+ goto out;
+
+ while ((mpath = rhashtable_walk_next(&iter))) {
+ if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
+ continue;
+ if (IS_ERR(mpath))
+ break;
+ __mesh_path_del(tbl, mpath);
}
+out:
+ rhashtable_walk_stop(&iter);
+ rhashtable_walk_exit(&iter);
}
/**
@@ -863,16 +672,8 @@ static void table_flush_by_iface(struct mesh_table *tbl,
*/
void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
{
- struct mesh_table *tbl;
-
- rcu_read_lock();
- read_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- tbl = resize_dereference_mesh_paths(sdata);
- table_flush_by_iface(tbl, sdata);
- tbl = resize_dereference_mpp_paths(sdata);
- table_flush_by_iface(tbl, sdata);
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- rcu_read_unlock();
+ table_flush_by_iface(sdata->u.mesh.mesh_paths);
+ table_flush_by_iface(sdata->u.mesh.mpp_paths);
}
/**
@@ -884,36 +685,25 @@ void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
*
* Returns: 0 if successful
*/
-static int table_path_del(struct mesh_table __rcu *rcu_tbl,
+static int table_path_del(struct mesh_table *tbl,
struct ieee80211_sub_if_data *sdata,
const u8 *addr)
{
- struct mesh_table *tbl;
struct mesh_path *mpath;
- struct mpath_node *node;
- struct hlist_head *bucket;
- int hash_idx;
- int err = 0;
-
- tbl = resize_dereference_paths(sdata, rcu_tbl);
- hash_idx = mesh_table_hash(addr, tbl);
- bucket = &tbl->hash_buckets[hash_idx];
-
- spin_lock(&tbl->hashwlock[hash_idx]);
- hlist_for_each_entry(node, bucket, list) {
- mpath = node->mpath;
- if (ether_addr_equal(addr, mpath->dst)) {
- __mesh_path_del(tbl, node);
- goto enddel;
- }
+
+ rcu_read_lock();
+ mpath = rhashtable_lookup_fast(&tbl->rhead, addr, mesh_rht_params);
+ if (!mpath) {
+ rcu_read_unlock();
+ return -ENXIO;
}
- err = -ENXIO;
-enddel:
- spin_unlock(&tbl->hashwlock[hash_idx]);
- return err;
+ __mesh_path_del(tbl, mpath);
+ rcu_read_unlock();
+ return 0;
}
+
/**
* mesh_path_del - delete a mesh path from the table
*
@@ -924,36 +714,13 @@ enddel:
*/
int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr)
{
- int err = 0;
+ int err;
/* flush relevant mpp entries first */
mpp_flush_by_proxy(sdata, addr);
- read_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
err = table_path_del(sdata->u.mesh.mesh_paths, sdata, addr);
sdata->u.mesh.mesh_paths_generation++;
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
-
- return err;
-}
-
-/**
- * mpp_path_del - delete a mesh proxy path from the table
- *
- * @addr: addr address (ETH_ALEN length)
- * @sdata: local subif
- *
- * Returns: 0 if successful
- */
-static int mpp_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr)
-{
- int err = 0;
-
- read_lock_bh(&sdata->u.mesh.pathtbl_resize_lock);
- err = table_path_del(sdata->u.mesh.mpp_paths, sdata, addr);
- sdata->u.mesh.mpp_paths_generation++;
- read_unlock_bh(&sdata->u.mesh.pathtbl_resize_lock);
-
return err;
}
@@ -987,18 +754,17 @@ int mesh_path_send_to_gates(struct mesh_path *mpath)
struct ieee80211_sub_if_data *sdata = mpath->sdata;
struct mesh_table *tbl;
struct mesh_path *from_mpath = mpath;
- struct mesh_path *gate = NULL;
+ struct mesh_path *gate;
bool copy = false;
struct hlist_head *known_gates;
- rcu_read_lock();
- tbl = rcu_dereference(sdata->u.mesh.mesh_paths);
+ tbl = sdata->u.mesh.mesh_paths;
known_gates = tbl->known_gates;
- rcu_read_unlock();
if (!known_gates)
return -EHOSTUNREACH;
+ rcu_read_lock();
hlist_for_each_entry_rcu(gate, known_gates, gate_list) {
if (gate->flags & MESH_PATH_ACTIVE) {
mpath_dbg(sdata, "Forwarding to %pM\n", gate->dst);
@@ -1016,6 +782,7 @@ int mesh_path_send_to_gates(struct mesh_path *mpath)
mpath_dbg(sdata, "Sending to %pM\n", gate->dst);
mesh_path_tx_pending(gate);
}
+ rcu_read_unlock();
return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
}
@@ -1072,118 +839,73 @@ void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
mesh_path_tx_pending(mpath);
}
-static void mesh_path_node_free(struct hlist_node *p, bool free_leafs)
-{
- struct mesh_path *mpath;
- struct mpath_node *node = hlist_entry(p, struct mpath_node, list);
- mpath = node->mpath;
- hlist_del_rcu(p);
- if (free_leafs) {
- del_timer_sync(&mpath->timer);
- kfree(mpath);
- }
- kfree(node);
-}
-
-static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
-{
- struct mesh_path *mpath;
- struct mpath_node *node, *new_node;
- u32 hash_idx;
-
- new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
- if (new_node == NULL)
- return -ENOMEM;
-
- node = hlist_entry(p, struct mpath_node, list);
- mpath = node->mpath;
- new_node->mpath = mpath;
- hash_idx = mesh_table_hash(mpath->dst, newtbl);
- hlist_add_head(&new_node->list,
- &newtbl->hash_buckets[hash_idx]);
- return 0;
-}
-
int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata)
{
struct mesh_table *tbl_path, *tbl_mpp;
int ret;
- tbl_path = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
+ tbl_path = mesh_table_alloc();
if (!tbl_path)
return -ENOMEM;
- tbl_path->free_node = &mesh_path_node_free;
- tbl_path->copy_node = &mesh_path_node_copy;
- tbl_path->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
- if (!tbl_path->known_gates) {
- ret = -ENOMEM;
- goto free_path;
- }
- INIT_HLIST_HEAD(tbl_path->known_gates);
-
- tbl_mpp = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
+ tbl_mpp = mesh_table_alloc();
if (!tbl_mpp) {
ret = -ENOMEM;
goto free_path;
}
- tbl_mpp->free_node = &mesh_path_node_free;
- tbl_mpp->copy_node = &mesh_path_node_copy;
- tbl_mpp->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
- if (!tbl_mpp->known_gates) {
- ret = -ENOMEM;
- goto free_mpp;
- }
- INIT_HLIST_HEAD(tbl_mpp->known_gates);
- rwlock_init(&sdata->u.mesh.pathtbl_resize_lock);
+ rhashtable_init(&tbl_path->rhead, &mesh_rht_params);
+ rhashtable_init(&tbl_mpp->rhead, &mesh_rht_params);
- /* Need no locking since this is during init */
- RCU_INIT_POINTER(sdata->u.mesh.mesh_paths, tbl_path);
- RCU_INIT_POINTER(sdata->u.mesh.mpp_paths, tbl_mpp);
+ sdata->u.mesh.mesh_paths = tbl_path;
+ sdata->u.mesh.mpp_paths = tbl_mpp;
return 0;
-free_mpp:
- mesh_table_free(tbl_mpp, true);
free_path:
- mesh_table_free(tbl_path, true);
+ mesh_table_free(tbl_path);
return ret;
}
-void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
+static
+void mesh_path_tbl_expire(struct ieee80211_sub_if_data *sdata,
+ struct mesh_table *tbl)
{
- struct mesh_table *tbl;
struct mesh_path *mpath;
- struct mpath_node *node;
- int i;
+ struct rhashtable_iter iter;
+ int ret;
- rcu_read_lock();
- tbl = rcu_dereference(sdata->u.mesh.mesh_paths);
- for_each_mesh_entry(tbl, node, i) {
- mpath = node->mpath;
+ ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_KERNEL);
+ if (ret)
+ return;
+
+ ret = rhashtable_walk_start(&iter);
+ if (ret && ret != -EAGAIN)
+ goto out;
+
+ while ((mpath = rhashtable_walk_next(&iter))) {
+ if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
+ continue;
+ if (IS_ERR(mpath))
+ break;
if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
(!(mpath->flags & MESH_PATH_FIXED)) &&
time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
- mesh_path_del(sdata, mpath->dst);
- }
-
- tbl = rcu_dereference(sdata->u.mesh.mpp_paths);
- for_each_mesh_entry(tbl, node, i) {
- mpath = node->mpath;
- if ((!(mpath->flags & MESH_PATH_FIXED)) &&
- time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
- mpp_path_del(sdata, mpath->dst);
+ __mesh_path_del(tbl, mpath);
}
+out:
+ rhashtable_walk_stop(&iter);
+ rhashtable_walk_exit(&iter);
+}
- rcu_read_unlock();
+void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
+{
+ mesh_path_tbl_expire(sdata, sdata->u.mesh.mesh_paths);
+ mesh_path_tbl_expire(sdata, sdata->u.mesh.mpp_paths);
}
void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata)
{
- /* no need for locking during exit path */
- mesh_table_free(rcu_dereference_protected(sdata->u.mesh.mesh_paths, 1),
- true);
- mesh_table_free(rcu_dereference_protected(sdata->u.mesh.mpp_paths, 1),
- true);
+ mesh_table_free(sdata->u.mesh.mesh_paths);
+ mesh_table_free(sdata->u.mesh.mpp_paths);
}
--
2.6.1
On 02/28/16 at 08:06pm, Bob Copeland wrote:
> In certain cases, the 802.11 mesh pathtable code wants to
> iterate over all of the entries in the forwarding table from
> the receive path, which is inside an RCU read-side critical
> section. Enable walks inside atomic sections by allowing
> GFP_ATOMIC allocations for the walker state.
>
> Change all existing callsites to pass in GFP_KERNEL.
>
> Cc: Thomas Graf <[email protected]>
> Cc: [email protected]
> Signed-off-by: Bob Copeland <[email protected]>
rhashtable bits LGTM
Acked-by: Thomas Graf <[email protected]>
On Tue, Mar 01, 2016 at 02:54:16PM +0100, Johannes Berg wrote:
> On Sun, 2016-02-28 at 20:06 -0500, Bob Copeland wrote:
> > In certain cases, the 802.11 mesh pathtable code wants to
> > iterate over all of the entries in the forwarding table from
> > the receive path, which is inside an RCU read-side critical
> > section.??Enable walks inside atomic sections by allowing
> > GFP_ATOMIC allocations for the walker state.
> >
> > Change all existing callsites to pass in GFP_KERNEL.
>
> Both look fine to me.
>
> I see you have more patches for mesh, so this probably can't go through
> net-next tree directly.
Yeah, these two are on top of the other mesh path table changes.
So either both of these could go via mac80211-next or we could do the
1/2 in net-next and wait to apply 2/2 in mac80211-next. Whatever works
for you guys.
--
Bob Copeland %% http://bobcopeland.com/
On Sun, 2016-02-28 at 20:06 -0500, Bob Copeland wrote:
> In certain cases, the 802.11 mesh pathtable code wants to
> iterate over all of the entries in the forwarding table from
> the receive path, which is inside an RCU read-side critical
> section. Enable walks inside atomic sections by allowing
> GFP_ATOMIC allocations for the walker state.
>
> Change all existing callsites to pass in GFP_KERNEL.
Both look fine to me.
I see you have more patches for mesh, so this probably can't go through
net-next tree directly.
johannes