IB/mthca: Optimize large messages on Sinai HCAs
Sinai (one-port PCI Express) HCAs get improved throughput for messages
bigger than 80 KB in DDR mode if memory keys are formatted in a
specific way. The enhancement only works if the memory key table is
smaller than 2^24 entries. For larger tables, the enhancement is off
and a warning is printed (to avoid silent performance loss).
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Michael Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/mthca/mthca_mr.c b/drivers/infiniband/hw/mthca/mthca_mr.c
index 0b48048..698b621 100644
--- a/drivers/infiniband/hw/mthca/mthca_mr.c
+++ b/drivers/infiniband/hw/mthca/mthca_mr.c
@@ -76,6 +76,8 @@
#define MTHCA_MPT_STATUS_SW 0xF0
#define MTHCA_MPT_STATUS_HW 0x00
+#define SINAI_FMR_KEY_INC 0x1000000
+
/*
* Buddy allocator for MTT segments (currently not very efficient
* since it doesn't keep a free list and just searches linearly
@@ -330,6 +332,14 @@
return tavor_key_to_hw_index(key);
}
+static inline u32 adjust_key(struct mthca_dev *dev, u32 key)
+{
+ if (dev->mthca_flags & MTHCA_FLAG_SINAI_OPT)
+ return ((key << 20) & 0x800000) | (key & 0x7fffff);
+ else
+ return key;
+}
+
int mthca_mr_alloc(struct mthca_dev *dev, u32 pd, int buffer_size_shift,
u64 iova, u64 total_size, u32 access, struct mthca_mr *mr)
{
@@ -345,6 +355,7 @@
key = mthca_alloc(&dev->mr_table.mpt_alloc);
if (key == -1)
return -ENOMEM;
+ key = adjust_key(dev, key);
mr->ibmr.rkey = mr->ibmr.lkey = hw_index_to_key(dev, key);
if (mthca_is_memfree(dev)) {
@@ -504,6 +515,7 @@
key = mthca_alloc(&dev->mr_table.mpt_alloc);
if (key == -1)
return -ENOMEM;
+ key = adjust_key(dev, key);
idx = key & (dev->limits.num_mpts - 1);
mr->ibmr.rkey = mr->ibmr.lkey = hw_index_to_key(dev, key);
@@ -687,7 +699,10 @@
++fmr->maps;
key = arbel_key_to_hw_index(fmr->ibmr.lkey);
- key += dev->limits.num_mpts;
+ if (dev->mthca_flags & MTHCA_FLAG_SINAI_OPT)
+ key += SINAI_FMR_KEY_INC;
+ else
+ key += dev->limits.num_mpts;
fmr->ibmr.lkey = fmr->ibmr.rkey = arbel_hw_index_to_key(key);
*(u8 *) fmr->mem.arbel.mpt = MTHCA_MPT_STATUS_SW;
@@ -760,6 +775,9 @@
else
dev->mthca_flags |= MTHCA_FLAG_FMR;
+ if (dev->mthca_flags & MTHCA_FLAG_SINAI_OPT)
+ mthca_dbg(dev, "Memory key throughput optimization activated.\n");
+
err = mthca_buddy_init(&dev->mr_table.mtt_buddy,
fls(dev->limits.num_mtt_segs - 1));