IB/mthca: Always fill MTTs from CPU

Speed up memory registration by filling in MTTs directly when the CPU
can write directly to the whole table (all mem-free cards, and to
Tavor mode on 64-bit systems with the patch I posted earlier).  This
reduces the number of FW commands needed to register an MR by at least
a factor of 2 and speeds up memory registration significantly.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/hw/mthca/mthca_dev.h b/drivers/infiniband/hw/mthca/mthca_dev.h
index fe5cecf70feddd6ec1b4c4d79dd32713d558126c..b7e42efaf43df30a5981503af8d80f3111a17038 100644 (file)
--- a/drivers/infiniband/hw/mthca/mthca_dev.h
+++ b/drivers/infiniband/hw/mthca/mthca_dev.h
@@ -464,6 +464,8 @@ void mthca_uar_free(struct mthca_dev *dev, struct mthca_uar *uar);
 int mthca_pd_alloc(struct mthca_dev *dev, int privileged, struct mthca_pd *pd);
 void mthca_pd_free(struct mthca_dev *dev, struct mthca_pd *pd);
 
+int mthca_write_mtt_size(struct mthca_dev *dev);
+
 struct mthca_mtt *mthca_alloc_mtt(struct mthca_dev *dev, int size);
 void mthca_free_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt);
 int mthca_write_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt,

diff --git a/drivers/infiniband/hw/mthca/mthca_mr.c b/drivers/infiniband/hw/mthca/mthca_mr.c
index 958c6d5b6bc0c02affb5f47083f950f3eb4b4d70..6037dd3f87dfa16e8a165a9c41adc17538e69b51 100644 (file)
--- a/drivers/infiniband/hw/mthca/mthca_mr.c
+++ b/drivers/infiniband/hw/mthca/mthca_mr.c
@@ -243,8 +243,8 @@ void mthca_free_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt)
        kfree(mtt);
 }
 
-int mthca_write_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt,
-                   int start_index, u64 *buffer_list, int list_len)
+static int __mthca_write_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt,
+                            int start_index, u64 *buffer_list, int list_len)
 {
        struct mthca_mailbox *mailbox;
        __be64 *mtt_entry;
@@ -295,6 +295,84 @@ out:
        return err;
 }
 
+int mthca_write_mtt_size(struct mthca_dev *dev)
+{
+       if (dev->mr_table.fmr_mtt_buddy != &dev->mr_table.mtt_buddy)
+               /*
+                * Be friendly to WRITE_MTT command
+                * and leave two empty slots for the
+                * index and reserved fields of the
+                * mailbox.
+                */
+               return PAGE_SIZE / sizeof (u64) - 2;
+
+       /* For Arbel, all MTTs must fit in the same page. */
+       return mthca_is_memfree(dev) ? (PAGE_SIZE / sizeof (u64)) : 0x7ffffff;
+}
+
+void mthca_tavor_write_mtt_seg(struct mthca_dev *dev, struct mthca_mtt *mtt,
+                             int start_index, u64 *buffer_list, int list_len)
+{
+       u64 __iomem *mtts;
+       int i;
+
+       mtts = dev->mr_table.tavor_fmr.mtt_base + mtt->first_seg * MTHCA_MTT_SEG_SIZE +
+               start_index * sizeof (u64);
+       for (i = 0; i < list_len; ++i)
+               mthca_write64_raw(cpu_to_be64(buffer_list[i] | MTHCA_MTT_FLAG_PRESENT),
+                                 mtts + i);
+}
+
+void mthca_arbel_write_mtt_seg(struct mthca_dev *dev, struct mthca_mtt *mtt,
+                             int start_index, u64 *buffer_list, int list_len)
+{
+       __be64 *mtts;
+       dma_addr_t dma_handle;
+       int i;
+       int s = start_index * sizeof (u64);
+
+       /* For Arbel, all MTTs must fit in the same page. */
+       BUG_ON(s / PAGE_SIZE != (s + list_len * sizeof(u64) - 1) / PAGE_SIZE);
+       /* Require full segments */
+       BUG_ON(s % MTHCA_MTT_SEG_SIZE);
+
+       mtts = mthca_table_find(dev->mr_table.mtt_table, mtt->first_seg +
+                               s / MTHCA_MTT_SEG_SIZE, &dma_handle);
+
+       BUG_ON(!mtts);
+
+       for (i = 0; i < list_len; ++i)
+               mtts[i] = cpu_to_be64(buffer_list[i] | MTHCA_MTT_FLAG_PRESENT);
+
+       dma_sync_single(&dev->pdev->dev, dma_handle, list_len * sizeof (u64), DMA_TO_DEVICE);
+}
+
+int mthca_write_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt,
+                   int start_index, u64 *buffer_list, int list_len)
+{
+       int size = mthca_write_mtt_size(dev);
+       int chunk;
+
+       if (dev->mr_table.fmr_mtt_buddy != &dev->mr_table.mtt_buddy)
+               return __mthca_write_mtt(dev, mtt, start_index, buffer_list, list_len);
+
+       while (list_len > 0) {
+               chunk = min(size, list_len);
+               if (mthca_is_memfree(dev))
+                       mthca_arbel_write_mtt_seg(dev, mtt, start_index,
+                                                 buffer_list, chunk);
+               else
+                       mthca_tavor_write_mtt_seg(dev, mtt, start_index,
+                                                 buffer_list, chunk);
+
+               list_len    -= chunk;
+               start_index += chunk;
+               buffer_list += chunk;
+       }
+
+       return 0;
+}
+
 static inline u32 tavor_hw_index_to_key(u32 ind)
 {
        return ind;

diff --git a/drivers/infiniband/hw/mthca/mthca_provider.c b/drivers/infiniband/hw/mthca/mthca_provider.c
index 7b96751695eac20deb60c8c60e13eb2032a0763f..0725ad7ad9bf7ca43b31f96609311bb2defbfea9 100644 (file)
--- a/drivers/infiniband/hw/mthca/mthca_provider.c
+++ b/drivers/infiniband/hw/mthca/mthca_provider.c
@@ -1015,6 +1015,7 @@ static struct ib_mr *mthca_reg_user_mr(struct ib_pd *pd, struct ib_umem *region,
        int shift, n, len;
        int i, j, k;
        int err = 0;
+       int write_mtt_size;
 
        shift = ffs(region->page_size) - 1;
 
@@ -1040,6 +1041,8 @@ static struct ib_mr *mthca_reg_user_mr(struct ib_pd *pd, struct ib_umem *region,
 
        i = n = 0;
 
+       write_mtt_size = min(mthca_write_mtt_size(dev), (int) (PAGE_SIZE / sizeof *pages));
+
        list_for_each_entry(chunk, &region->chunk_list, list)
                for (j = 0; j < chunk->nmap; ++j) {
                        len = sg_dma_len(&chunk->page_list[j]) >> shift;
@@ -1047,14 +1050,11 @@ static struct ib_mr *mthca_reg_user_mr(struct ib_pd *pd, struct ib_umem *region,
                                pages[i++] = sg_dma_address(&chunk->page_list[j]) +
                                        region->page_size * k;
                                /*
-                                * Be friendly to WRITE_MTT command
-                                * and leave two empty slots for the
-                                * index and reserved fields of the
-                                * mailbox.
+                                * Be friendly to write_mtt and pass it chunks
+                                * of appropriate size.
                                 */
-                               if (i == PAGE_SIZE / sizeof (u64) - 2) {
-                                       err = mthca_write_mtt(dev, mr->mtt,
-                                                             n, pages, i);
+                               if (i == write_mtt_size) {
+                                       err = mthca_write_mtt(dev, mr->mtt, n, pages, i);
                                        if (err)
                                                goto mtt_done;
                                        n += i;