static struct kmem_cache *rds_ib_frag_slab;
static atomic_t rds_ib_allocation = ATOMIC_INIT(0);
-/* Free frag and attached recv buffer f_sg */
-static void rds_ib_frag_free(struct rds_page_frag *frag)
-{
- rdsdebug("frag %p page %p\n", frag, sg_page(&frag->f_sg));
- __free_page(sg_page(&frag->f_sg));
- kmem_cache_free(rds_ib_frag_slab, frag);
-}
-
void rds_ib_recv_init_ring(struct rds_ib_connection *ic)
{
struct rds_ib_recv_work *recv;
}
}
+/*
+ * The entire 'from' list, including the from element itself, is put on
+ * to the tail of the 'to' list.
+ */
+static void list_splice_entire_tail(struct list_head *from,
+ struct list_head *to)
+{
+ struct list_head *from_last = from->prev;
+
+ list_splice_tail(from_last, to);
+ list_add_tail(from_last, to);
+}
+
+static void rds_ib_cache_xfer_to_ready(struct rds_ib_refill_cache *cache)
+{
+ struct list_head *tmp;
+
+ tmp = xchg(&cache->xfer, NULL);
+ if (tmp) {
+ if (cache->ready)
+ list_splice_entire_tail(tmp, cache->ready);
+ else
+ cache->ready = tmp;
+ }
+}
+
+static int rds_ib_recv_alloc_cache(struct rds_ib_refill_cache *cache)
+{
+ struct rds_ib_cache_head *head;
+ int cpu;
+
+ cache->percpu = alloc_percpu(struct rds_ib_cache_head);
+ if (!cache->percpu)
+ return -ENOMEM;
+
+ for_each_possible_cpu(cpu) {
+ head = per_cpu_ptr(cache->percpu, cpu);
+ head->first = NULL;
+ head->count = 0;
+ }
+ cache->xfer = NULL;
+ cache->ready = NULL;
+
+ return 0;
+}
+
+int rds_ib_recv_alloc_caches(struct rds_ib_connection *ic)
+{
+ int ret;
+
+ ret = rds_ib_recv_alloc_cache(&ic->i_cache_incs);
+ if (!ret) {
+ ret = rds_ib_recv_alloc_cache(&ic->i_cache_frags);
+ if (ret)
+ free_percpu(ic->i_cache_incs.percpu);
+ }
+
+ return ret;
+}
+
+static void rds_ib_cache_splice_all_lists(struct rds_ib_refill_cache *cache,
+ struct list_head *caller_list)
+{
+ struct rds_ib_cache_head *head;
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ head = per_cpu_ptr(cache->percpu, cpu);
+ if (head->first) {
+ list_splice_entire_tail(head->first, caller_list);
+ head->first = NULL;
+ }
+ }
+
+ if (cache->ready) {
+ list_splice_entire_tail(cache->ready, caller_list);
+ cache->ready = NULL;
+ }
+}
+
+void rds_ib_recv_free_caches(struct rds_ib_connection *ic)
+{
+ struct rds_ib_incoming *inc;
+ struct rds_ib_incoming *inc_tmp;
+ struct rds_page_frag *frag;
+ struct rds_page_frag *frag_tmp;
+ LIST_HEAD(list);
+
+ rds_ib_cache_xfer_to_ready(&ic->i_cache_incs);
+ rds_ib_cache_splice_all_lists(&ic->i_cache_incs, &list);
+ free_percpu(ic->i_cache_incs.percpu);
+
+ list_for_each_entry_safe(inc, inc_tmp, &list, ii_cache_entry) {
+ list_del(&inc->ii_cache_entry);
+ WARN_ON(!list_empty(&inc->ii_frags));
+ kmem_cache_free(rds_ib_incoming_slab, inc);
+ }
+
+ rds_ib_cache_xfer_to_ready(&ic->i_cache_frags);
+ rds_ib_cache_splice_all_lists(&ic->i_cache_frags, &list);
+ free_percpu(ic->i_cache_frags.percpu);
+
+ list_for_each_entry_safe(frag, frag_tmp, &list, f_cache_entry) {
+ list_del(&frag->f_cache_entry);
+ WARN_ON(!list_empty(&frag->f_item));
+ kmem_cache_free(rds_ib_frag_slab, frag);
+ }
+}
+
+/* fwd decl */
+static void rds_ib_recv_cache_put(struct list_head *new_item,
+ struct rds_ib_refill_cache *cache);
+static struct list_head *rds_ib_recv_cache_get(struct rds_ib_refill_cache *cache);
+
+
+/* Recycle frag and attached recv buffer f_sg */
+static void rds_ib_frag_free(struct rds_ib_connection *ic,
+ struct rds_page_frag *frag)
+{
+ rdsdebug("frag %p page %p\n", frag, sg_page(&frag->f_sg));
+
+ rds_ib_recv_cache_put(&frag->f_cache_entry, &ic->i_cache_frags);
+}
+
+/* Recycle inc after freeing attached frags */
+void rds_ib_inc_free(struct rds_incoming *inc)
+{
+ struct rds_ib_incoming *ibinc;
+ struct rds_page_frag *frag;
+ struct rds_page_frag *pos;
+ struct rds_ib_connection *ic = inc->i_conn->c_transport_data;
+
+ ibinc = container_of(inc, struct rds_ib_incoming, ii_inc);
+
+ /* Free attached frags */
+ list_for_each_entry_safe(frag, pos, &ibinc->ii_frags, f_item) {
+ list_del_init(&frag->f_item);
+ rds_ib_frag_free(ic, frag);
+ }
+ BUG_ON(!list_empty(&ibinc->ii_frags));
+
+ rdsdebug("freeing ibinc %p inc %p\n", ibinc, inc);
+ rds_ib_recv_cache_put(&ibinc->ii_cache_entry, &ic->i_cache_incs);
+}
+
static void rds_ib_recv_clear_one(struct rds_ib_connection *ic,
struct rds_ib_recv_work *recv)
{
}
if (recv->r_frag) {
ib_dma_unmap_sg(ic->i_cm_id->device, &recv->r_frag->f_sg, 1, DMA_FROM_DEVICE);
- rds_ib_frag_free(recv->r_frag);
+ rds_ib_frag_free(ic, recv->r_frag);
recv->r_frag = NULL;
}
}
rds_ib_recv_clear_one(ic, &ic->i_recvs[i]);
}
+static struct rds_ib_incoming *rds_ib_refill_one_inc(struct rds_ib_connection *ic)
+{
+ struct rds_ib_incoming *ibinc;
+ struct list_head *cache_item;
+ int avail_allocs;
+
+ cache_item = rds_ib_recv_cache_get(&ic->i_cache_incs);
+ if (cache_item) {
+ ibinc = container_of(cache_item, struct rds_ib_incoming, ii_cache_entry);
+ } else {
+ avail_allocs = atomic_add_unless(&rds_ib_allocation,
+ 1, rds_ib_sysctl_max_recv_allocation);
+ if (!avail_allocs) {
+ rds_ib_stats_inc(s_ib_rx_alloc_limit);
+ return NULL;
+ }
+ ibinc = kmem_cache_alloc(rds_ib_incoming_slab, GFP_NOWAIT);
+ if (!ibinc) {
+ atomic_dec(&rds_ib_allocation);
+ return NULL;
+ }
+ }
+ INIT_LIST_HEAD(&ibinc->ii_frags);
+ rds_inc_init(&ibinc->ii_inc, ic->conn, ic->conn->c_faddr);
+
+ return ibinc;
+}
+
+static struct rds_page_frag *rds_ib_refill_one_frag(struct rds_ib_connection *ic)
+{
+ struct rds_page_frag *frag;
+ struct list_head *cache_item;
+ int ret;
+
+ cache_item = rds_ib_recv_cache_get(&ic->i_cache_frags);
+ if (cache_item) {
+ frag = container_of(cache_item, struct rds_page_frag, f_cache_entry);
+ } else {
+ frag = kmem_cache_alloc(rds_ib_frag_slab, GFP_NOWAIT);
+ if (!frag)
+ return NULL;
+
+ ret = rds_page_remainder_alloc(&frag->f_sg,
+ RDS_FRAG_SIZE, GFP_NOWAIT);
+ if (ret) {
+ kmem_cache_free(rds_ib_frag_slab, frag);
+ return NULL;
+ }
+ }
+
+ INIT_LIST_HEAD(&frag->f_item);
+
+ return frag;
+}
+
static int rds_ib_recv_refill_one(struct rds_connection *conn,
struct rds_ib_recv_work *recv)
{
struct ib_sge *sge;
int ret = -ENOMEM;
+ if (!ic->i_cache_incs.ready)
+ rds_ib_cache_xfer_to_ready(&ic->i_cache_incs);
+ if (!ic->i_cache_frags.ready)
+ rds_ib_cache_xfer_to_ready(&ic->i_cache_frags);
+
/*
* ibinc was taken from recv if recv contained the start of a message.
* recvs that were continuations will still have this allocated.
*/
if (!recv->r_ibinc) {
- if (!atomic_add_unless(&rds_ib_allocation, 1, rds_ib_sysctl_max_recv_allocation)) {
- rds_ib_stats_inc(s_ib_rx_alloc_limit);
- goto out;
- }
- recv->r_ibinc = kmem_cache_alloc(rds_ib_incoming_slab, GFP_NOWAIT);
- if (!recv->r_ibinc) {
- atomic_dec(&rds_ib_allocation);
+ recv->r_ibinc = rds_ib_refill_one_inc(ic);
+ if (!recv->r_ibinc)
goto out;
- }
- INIT_LIST_HEAD(&recv->r_ibinc->ii_frags);
- rds_inc_init(&recv->r_ibinc->ii_inc, conn, conn->c_faddr);
}
WARN_ON(recv->r_frag); /* leak! */
- recv->r_frag = kmem_cache_alloc(rds_ib_frag_slab, GFP_NOWAIT);
+ recv->r_frag = rds_ib_refill_one_frag(ic);
if (!recv->r_frag)
goto out;
- INIT_LIST_HEAD(&recv->r_frag->f_item);
- sg_init_table(&recv->r_frag->f_sg, 1);
- ret = rds_page_remainder_alloc(&recv->r_frag->f_sg,
- RDS_FRAG_SIZE, GFP_NOWAIT);
- if (ret) {
- kmem_cache_free(rds_ib_frag_slab, recv->r_frag);
- recv->r_frag = NULL;
- goto out;
- }
ret = ib_dma_map_sg(ic->i_cm_id->device, &recv->r_frag->f_sg,
1, DMA_FROM_DEVICE);
/*
* This tries to allocate and post unused work requests after making sure that
* they have all the allocations they need to queue received fragments into
- * sockets. The i_recv_mutex is held here so that ring_alloc and _unalloc
- * pairs don't go unmatched.
+ * sockets.
*
* -1 is returned if posting fails due to temporary resource exhaustion.
*/
return ret;
}
-static void rds_ib_inc_purge(struct rds_incoming *inc)
+/*
+ * We want to recycle several types of recv allocations, like incs and frags.
+ * To use this, the *_free() function passes in the ptr to a list_head within
+ * the recyclee, as well as the cache to put it on.
+ *
+ * First, we put the memory on a percpu list. When this reaches a certain size,
+ * We move it to an intermediate non-percpu list in a lockless manner, with some
+ * xchg/compxchg wizardry.
+ *
+ * N.B. Instead of a list_head as the anchor, we use a single pointer, which can
+ * be NULL and xchg'd. The list is actually empty when the pointer is NULL, and
+ * list_empty() will return true with one element is actually present.
+ */
+static void rds_ib_recv_cache_put(struct list_head *new_item,
+ struct rds_ib_refill_cache *cache)
{
- struct rds_ib_incoming *ibinc;
- struct rds_page_frag *frag;
- struct rds_page_frag *pos;
+ unsigned long flags;
+ struct rds_ib_cache_head *chp;
+ struct list_head *old;
- ibinc = container_of(inc, struct rds_ib_incoming, ii_inc);
- rdsdebug("purging ibinc %p inc %p\n", ibinc, inc);
+ local_irq_save(flags);
- list_for_each_entry_safe(frag, pos, &ibinc->ii_frags, f_item) {
- list_del_init(&frag->f_item);
- rds_ib_frag_free(frag);
- }
+ chp = per_cpu_ptr(cache->percpu, smp_processor_id());
+ if (!chp->first)
+ INIT_LIST_HEAD(new_item);
+ else /* put on front */
+ list_add_tail(new_item, chp->first);
+ chp->first = new_item;
+ chp->count++;
+
+ if (chp->count < RDS_IB_RECYCLE_BATCH_COUNT)
+ goto end;
+
+ /*
+ * Return our per-cpu first list to the cache's xfer by atomically
+ * grabbing the current xfer list, appending it to our per-cpu list,
+ * and then atomically returning that entire list back to the
+ * cache's xfer list as long as it's still empty.
+ */
+ do {
+ old = xchg(&cache->xfer, NULL);
+ if (old)
+ list_splice_entire_tail(old, chp->first);
+ old = cmpxchg(&cache->xfer, NULL, chp->first);
+ } while (old);
+
+ chp->first = NULL;
+ chp->count = 0;
+end:
+ local_irq_restore(flags);
}
-void rds_ib_inc_free(struct rds_incoming *inc)
+static struct list_head *rds_ib_recv_cache_get(struct rds_ib_refill_cache *cache)
{
- struct rds_ib_incoming *ibinc;
-
- ibinc = container_of(inc, struct rds_ib_incoming, ii_inc);
+ struct list_head *head = cache->ready;
+
+ if (head) {
+ if (!list_empty(head)) {
+ cache->ready = head->next;
+ list_del_init(head);
+ } else
+ cache->ready = NULL;
+ }
- rds_ib_inc_purge(inc);
- rdsdebug("freeing ibinc %p inc %p\n", ibinc, inc);
- BUG_ON(!list_empty(&ibinc->ii_frags));
- kmem_cache_free(rds_ib_incoming_slab, ibinc);
- atomic_dec(&rds_ib_allocation);
- BUG_ON(atomic_read(&rds_ib_allocation) < 0);
+ return head;
}
int rds_ib_inc_copy_to_user(struct rds_incoming *inc, struct iovec *first_iov,
*
* FIXME: Fold this into the code path below.
*/
- rds_ib_frag_free(recv->r_frag);
+ rds_ib_frag_free(ic, recv->r_frag);
recv->r_frag = NULL;
return;
}
git.openpandora.org / pandora-kernel.git / blobdiff