Batch vmq unmap grant operations.

Signed-off-by: Jose Renato Santos <jsantos@hpl.hp.com>

diff --git a/drivers/xen/netchannel2/chan.c b/drivers/xen/netchannel2/chan.c
index 98a1f908beccc01a4e77e960372ddf4a0dbec8db..185f6221d3cf6c3def614fcd4d457934278dd81f 100644 (file)
--- a/drivers/xen/netchannel2/chan.c
+++ b/drivers/xen/netchannel2/chan.c
@@ -894,10 +894,13 @@ static int process_ring(struct napi_struct *napi,
                    This must happen before we flush the rings, since
                    that's when the PACKET messages will be made
                    visible to the other end. */
-                if (ncrp == &nc->rings)
+                if (ncrp == &nc->rings) {
                         flush_hypercall_batcher(&nc->batcher,
                                                 nc2_posted_on_gntcopy_fail);
-
+#ifdef CONFIG_XEN_NETDEV2_VMQ
+                       vmq_flush_unmap_hypercall();
+#endif
+               }
                 flush_rings(ncrp);
 
                 while ((skb = __skb_dequeue(&ncrp->release_on_flush_batcher))){

diff --git a/drivers/xen/netchannel2/vmq.c b/drivers/xen/netchannel2/vmq.c
index 6ef653938098a2ffc3e1723114e86172b9112bd4..39b07b5912c5398ee1d1d802e52f797154fa101d 100644 (file)
--- a/drivers/xen/netchannel2/vmq.c
+++ b/drivers/xen/netchannel2/vmq.c
@@ -47,6 +47,39 @@
 #define VMQ_QUEUE_ENABLED   2
 #define VMQ_QUEUE_CLOSING   3
 
+#define VMQ_MAX_UNMAP_OPS 256
+struct vmq_unmap_grants {
+        unsigned n;
+        gnttab_unmap_grant_ref_t gop[VMQ_MAX_UNMAP_OPS];
+};
+typedef struct vmq_unmap_grants vmq_unmap_grants_t;
+
+vmq_unmap_grants_t vmq_unmap_grants;
+
+static inline void vmq_flush_unmap_grants(void)
+{
+        if (vmq_unmap_grants.n == 0)
+                return;
+
+        if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, 
+                                     vmq_unmap_grants.gop,
+                                     vmq_unmap_grants.n))
+            BUG();
+       vmq_unmap_grants.n = 0;
+}
+
+static inline gnttab_unmap_grant_ref_t *vmq_next_unmap_gop(void)
+{
+        if (vmq_unmap_grants.n == VMQ_MAX_UNMAP_OPS)
+                vmq_flush_unmap_grants();
+        return &vmq_unmap_grants.gop[vmq_unmap_grants.n++];
+}
+
+void vmq_flush_unmap_hypercall(void)
+{
+       vmq_flush_unmap_grants();
+}
+
 static inline unsigned long vmq_idx_to_pfn(nc2_vmq_t *vmq, unsigned int idx)
 {
         return page_to_pfn(vmq->pages[idx]);
@@ -271,19 +304,18 @@ static void nc2_vmq_unmap_buf(struct netchannel2 *nc,
 {
        nc2_vmq_t *vmq = &nc->vmq;
        unsigned long pfn;
-       gnttab_unmap_grant_ref_t gop;
+       gnttab_unmap_grant_ref_t *gop;
        unsigned prod;
-       int ret;
 
        pfn = vmq_idx_to_pfn(vmq, idx); 
        /* Already unmapped? */
        if (!phys_to_machine_mapping_valid(pfn))
                return;
-       gnttab_set_unmap_op(&gop, vmq_idx_to_kaddr(vmq, idx),
+
+       gop = vmq_next_unmap_gop();
+       gnttab_set_unmap_op(gop, vmq_idx_to_kaddr(vmq, idx),
                            GNTMAP_host_map,
                            vmq->buffer[idx].buf->grant_handle);
-       ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &gop, 1);
-       BUG_ON(ret);
 
        vmq->nbufs--;
 
@@ -321,6 +353,8 @@ static void nc2_vmq_free_mapped_bufs(struct netchannel2 *nc)
                nc2_vmq_unmap_buf(nc, idx, 1);
        }
 
+       vmq_flush_unmap_grants();
+
        vmq->mapped_pages_cons = cons;
 
 }
@@ -342,7 +376,9 @@ static void nc2_vmq_free_skb(struct sk_buff *skb)
                idx = nc2_vmq_page_index(frags[i].page);
                nc2_vmq_unmap_buf(nc, idx, 1);
        }
-       
+
+       vmq_flush_unmap_grants();
+
        shinfo->frag_list = NULL;
        shinfo->nr_frags = 0;
        
@@ -762,7 +798,7 @@ void xmit_vmq(struct netchannel2 *nc, struct sk_buff *skb,
        }
 
        /* Avoid unmapping frags grants when skb is freed later */
-       /* by nc2_vmq_fre_skb() */
+       /* by nc2_vmq_free_skb() */
        skb_shinfo(skb)->nr_frags = 0;
 }
 

diff --git a/drivers/xen/netchannel2/vmq.h b/drivers/xen/netchannel2/vmq.h
index 0af7924e2a50c68dd68b6718a12cb22847e3093d..91cba694b75c11a7211c2ef4df39cf5683a64316 100644 (file)
--- a/drivers/xen/netchannel2/vmq.h
+++ b/drivers/xen/netchannel2/vmq.h
@@ -9,6 +9,7 @@ void do_vmq_work(struct netchannel2 *nc);
 int nc2_is_vmq_packet(struct netchannel2 *nc, struct sk_buff *skb);
 void xmit_vmq(struct netchannel2 *nc, struct sk_buff *skb,
               volatile void *msg);
+void vmq_flush_unmap_hypercall(void);
 
 #define vmq_get(_b)                                            \
                atomic_inc(&(_b)->refcnt);