IB/mlx5: Introduce ODP diagnostic counters

Introduce ODP diagnostic counters and count the following
per MR within IB/mlx5 driver:
 1) Page faults:
	Total number of faulted pages.
 2) Page invalidations:
	Total number of pages invalidated by the OS during all
	invalidation events. The translations can be no longer
	valid due to either non-present pages or mapping changes.

Link: https://lore.kernel.org/r/20191016062308.11886-2-leon@kernel.org
Signed-off-by: Erez Alfasi <ereza@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index bf30d53d94dc54158b859acd60cfb74c80543abf..5aae05ebf64b4d82d2a51904b3b6cb6523b40e8e 100644 (file)
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -585,6 +585,9 @@ struct mlx5_ib_dm {
                                          IB_ACCESS_REMOTE_READ   |\
                                          IB_ZERO_BASED)
 
+#define mlx5_update_odp_stats(mr, counter_name, value)         \
+       atomic64_add(value, &((mr)->odp_stats.counter_name))
+
 struct mlx5_ib_mr {
        struct ib_mr            ibmr;
        void                    *descs;
@@ -622,6 +625,7 @@ struct mlx5_ib_mr {
        wait_queue_head_t       q_leaf_free;
        struct mlx5_async_work  cb_work;
        atomic_t                num_pending_prefetch;
+       struct ib_odp_counters  odp_stats;
 };
 
 static inline bool is_odp_mr(struct mlx5_ib_mr *mr)

diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c
index 95cf0249b0152f1e6a1494c39be1a5b43d497b0c..3601c6ad96f9995b1d430205e850b3ee448a31c0 100644 (file)
--- a/drivers/infiniband/hw/mlx5/odp.c
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -224,6 +224,7 @@ void mlx5_ib_invalidate_range(struct ib_umem_odp *umem_odp, unsigned long start,
        const u64 umr_block_mask = (MLX5_UMR_MTT_ALIGNMENT /
                                    sizeof(struct mlx5_mtt)) - 1;
        u64 idx = 0, blk_start_idx = 0;
+       u64 invalidations = 0;
        int in_block = 0;
        u64 addr;
 
@@ -261,6 +262,9 @@ void mlx5_ib_invalidate_range(struct ib_umem_odp *umem_odp, unsigned long start,
                                blk_start_idx = idx;
                                in_block = 1;
                        }
+
+                       /* Count page invalidations */
+                       invalidations += idx - blk_start_idx + 1;
                } else {
                        u64 umr_offset = idx & umr_block_mask;
 
@@ -279,6 +283,9 @@ void mlx5_ib_invalidate_range(struct ib_umem_odp *umem_odp, unsigned long start,
                                   MLX5_IB_UPD_XLT_ZAP |
                                   MLX5_IB_UPD_XLT_ATOMIC);
        mutex_unlock(&umem_odp->umem_mutex);
+
+       mlx5_update_odp_stats(mr, invalidations, invalidations);
+
        /*
         * We are now sure that the device will not access the
         * memory. We can safely unmap it, and mark it as dirty if
@@ -287,6 +294,7 @@ void mlx5_ib_invalidate_range(struct ib_umem_odp *umem_odp, unsigned long start,
 
        ib_umem_odp_unmap_dma_pages(umem_odp, start, end);
 
+
        if (unlikely(!umem_odp->npages && mr->parent &&
                     !umem_odp->dying)) {
                WRITE_ONCE(umem_odp->dying, 1);
@@ -801,6 +809,13 @@ static int pagefault_single_data_segment(struct mlx5_ib_dev *dev,
                if (ret < 0)
                        goto srcu_unlock;
 
+               /*
+                * When prefetching a page, page fault is generated
+                * in order to bring the page to the main memory.
+                * In the current flow, page faults are being counted.
+                */
+               mlx5_update_odp_stats(mr, faults, ret);
+
                npages += ret;
                ret = 0;
                break;

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index a465fcae992bc9b49a293d18d536675ec3db683c..1ef31b27a41c140f80ae2d981ccf301144c91010 100644 (file)
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -2220,6 +2220,11 @@ struct rdma_netdev_alloc_params {
                                      struct net_device *netdev, void *param);
 };
 
+struct ib_odp_counters {
+       atomic64_t faults;
+       atomic64_t invalidations;
+};
+
 struct ib_counters {
        struct ib_device        *device;
        struct ib_uobject       *uobject;