mac80211: mesh: use hlist for rmc cache

The RMC cache has 256 list heads plus a u32, which puts it at the
unfortunate size of 4104 bytes with padding.  kmalloc() will then
round this up to the next power-of-two, so we wind up actually
using two pages here where most of the second is wasted.

Switch to hlist heads here to reduce the structure size down to
fit within a page.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index d0d8eea..1a2aaf4 100644 (file)
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -174,22 +174,23 @@ int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
                return -ENOMEM;
        sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
        for (i = 0; i < RMC_BUCKETS; i++)
-               INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
+               INIT_HLIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
        return 0;
 }
 
 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 {
        struct mesh_rmc *rmc = sdata->u.mesh.rmc;
-       struct rmc_entry *p, *n;
+       struct rmc_entry *p;
+       struct hlist_node *n;
        int i;
 
        if (!sdata->u.mesh.rmc)
                return;
 
        for (i = 0; i < RMC_BUCKETS; i++) {
-               list_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
-                       list_del(&p->list);
+               hlist_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
+                       hlist_del(&p->list);
                        kmem_cache_free(rm_cache, p);
                }
        }
@@ -218,7 +219,8 @@ int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
        u32 seqnum = 0;
        int entries = 0;
        u8 idx;
-       struct rmc_entry *p, *n;
+       struct rmc_entry *p;
+       struct hlist_node *n;
 
        if (!rmc)
                return -1;
@@ -226,11 +228,11 @@ int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
        /* Don't care about endianness since only match matters */
        memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
        idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
-       list_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
+       hlist_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
                ++entries;
                if (time_after(jiffies, p->exp_time) ||
                    entries == RMC_QUEUE_MAX_LEN) {
-                       list_del(&p->list);
+                       hlist_del(&p->list);
                        kmem_cache_free(rm_cache, p);
                        --entries;
                } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
@@ -244,7 +246,7 @@ int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
        p->seqnum = seqnum;
        p->exp_time = jiffies + RMC_TIMEOUT;
        memcpy(p->sa, sa, ETH_ALEN);
-       list_add(&p->list, &rmc->bucket[idx]);
+       hlist_add_head(&p->list, &rmc->bucket[idx]);
        return 0;
 }
 

diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h
index e1415c9..bc3f9a3 100644 (file)
--- a/net/mac80211/mesh.h
+++ b/net/mac80211/mesh.h
@@ -158,14 +158,14 @@ struct mesh_table {
  * that are found in the cache.
  */
 struct rmc_entry {
-       struct list_head list;
+       struct hlist_node list;
        u32 seqnum;
        unsigned long exp_time;
        u8 sa[ETH_ALEN];
 };
 
 struct mesh_rmc {
-       struct list_head bucket[RMC_BUCKETS];
+       struct hlist_head bucket[RMC_BUCKETS];
        u32 idx_mask;
 };