From: Erez Alfasi <ereza@xxxxxxxxxxxx>
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 The translations can be no longer
valid due to either non-present pages or mapping changes.
3) Prefetched pages:
When prefetching a page, page fault is generated
in order to bring the page to the main memory.
The prefetched pages counter will be updated
during a page fault flow only if it was derived
from prefetching operation.
Signed-off-by: Erez Alfasi <ereza@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
---
drivers/infiniband/hw/mlx5/odp.c | 18 ++++++++++++++++++
include/rdma/ib_umem_odp.h | 14 ++++++++++++++
2 files changed, 32 insertions(+)
diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c
index 905936423a03..b7c8a49ac753 100644
--- a/drivers/infiniband/hw/mlx5/odp.c
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -287,6 +287,10 @@ void mlx5_ib_invalidate_range(struct ib_umem_odp *umem_odp, unsigned long start,
ib_umem_odp_unmap_dma_pages(umem_odp, start, end);
+ /* Count page invalidations */
+ ib_update_odp_stats(umem_odp, invalidations,
+ ib_umem_odp_num_pages(umem_odp));
+
if (unlikely(!umem_odp->npages && mr->parent &&
!umem_odp->dying)) {
WRITE_ONCE(umem_odp->dying, 1);
@@ -801,6 +805,20 @@ 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.
+ * Prefetched pages counter will be updated as well
+ * only if the current page fault flow was derived
+ * from prefetching flow.
+ */
+ ib_update_odp_stats(to_ib_umem_odp(mr->umem), faults, ret);
+
+ if (prefetch)
+ ib_update_odp_stats(to_ib_umem_odp(mr->umem),
+ prefetched, ret);
+
npages += ret;
ret = 0;
break;
diff --git a/include/rdma/ib_umem_odp.h b/include/rdma/ib_umem_odp.h
index b37c674b7fe6..3359e34516da 100644
--- a/include/rdma/ib_umem_odp.h
+++ b/include/rdma/ib_umem_odp.h
@@ -37,6 +37,12 @@
#include <rdma/ib_verbs.h>
#include <linux/interval_tree.h>
+struct ib_odp_counters {
+ atomic64_t faults;
+ atomic64_t invalidations;
+ atomic64_t prefetched;
+};
+
struct ib_umem_odp {
struct ib_umem umem;
struct ib_ucontext_per_mm *per_mm;
@@ -62,6 +68,11 @@ struct ib_umem_odp {
struct mutex umem_mutex;
void *private; /* for the HW driver to use. */
+ /*
+ * ODP diagnostic counters.
+ */
+ struct ib_odp_counters odp_stats;
+
int notifiers_seq;
int notifiers_count;
int npages;
@@ -106,6 +117,9 @@ static inline size_t ib_umem_odp_num_pages(struct ib_umem_odp *umem_odp)
umem_odp->page_shift;
}
+#define ib_update_odp_stats(umem_odp, counter_name, value) \
+ atomic64_add(value, &(umem_odp->odp_stats.counter_name))
+
/*
* The lower 2 bits of the DMA address signal the R/W permissions for
* the entry. To upgrade the permissions, provide the appropriate
--
2.20.1
