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RDMA/mlx4: Use ib_umem_find_best_pgsz() to calculate MTT size

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Convert mlx4 to use ib_umem_find_best_pgsz() instead of open-coded
variant to calculate MTT size.

Link: https://patch.msgid.link/c39ec6f5d4664c439a72f2961728ebb5895a9f07.1733233299.git.leonro@nvidia.com
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
This commit is contained in:
Leon Romanovsky
2024-12-03 15:42:25 +02:00
committed by Leon Romanovsky
parent 1f53d88cbb
commit d31ba16c43
4 changed files with 35 additions and 168 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/infiniband/hw/mlx4/cq.c
View File

@@ -150,8 +150,12 @@ static int mlx4_ib_get_cq_umem(struct mlx4_ib_dev *dev,
return PTR_ERR(*umem);
shift = mlx4_ib_umem_calc_optimal_mtt_size(*umem, 0, &n);
err = mlx4_mtt_init(dev->dev, n, shift, &buf->mtt);
if (shift < 0) {
err = shift;
goto err_buf;
}
err = mlx4_mtt_init(dev->dev, n, shift, &buf->mtt);
if (err)
goto err_buf;

18
drivers/infiniband/hw/mlx4/mlx4_ib.h
View File

@@ -667,6 +667,9 @@ struct mlx4_uverbs_ex_query_device {
__u32 reserved;
};
/* 4k - 4G */
#define MLX4_PAGE_SIZE_SUPPORTED ((unsigned long)GENMASK_ULL(31, 12))
static inline struct mlx4_ib_dev *to_mdev(struct ib_device *ibdev)
{
return container_of(ibdev, struct mlx4_ib_dev, ib_dev);
@@ -936,8 +939,19 @@ mlx4_ib_destroy_rwq_ind_table(struct ib_rwq_ind_table *wq_ind_table)
{
return 0;
}
int mlx4_ib_umem_calc_optimal_mtt_size(struct ib_umem *umem, u64 start_va,
int *num_of_mtts);
static inline int mlx4_ib_umem_calc_optimal_mtt_size(struct ib_umem *umem,
u64 start,
int *num_of_mtts)
{
unsigned long pg_sz;
pg_sz = ib_umem_find_best_pgsz(umem, MLX4_PAGE_SIZE_SUPPORTED, start);
if (!pg_sz)
return -EOPNOTSUPP;
*num_of_mtts = ib_umem_num_dma_blocks(umem, pg_sz);
return order_base_2(pg_sz);
}
int mlx4_ib_cm_init(void);
void mlx4_ib_cm_destroy(void);

167
drivers/infiniband/hw/mlx4/mr.c
View File

@@ -87,10 +87,6 @@ struct ib_mr *mlx4_ib_get_dma_mr(struct ib_pd *pd, int acc)
return ERR_PTR(err);
}
enum {
MLX4_MAX_MTT_SHIFT = 31
};
static int mlx4_ib_umem_write_mtt_block(struct mlx4_ib_dev *dev,
struct mlx4_mtt *mtt,
u64 mtt_size, u64 mtt_shift, u64 len,
@@ -144,41 +140,6 @@ static int mlx4_ib_umem_write_mtt_block(struct mlx4_ib_dev *dev,
return 0;
}
static inline u64 alignment_of(u64 ptr)
{
return ilog2(ptr & (~(ptr - 1)));
}
static int mlx4_ib_umem_calc_block_mtt(u64 next_block_start,
u64 current_block_end,
u64 block_shift)
{
/* Check whether the alignment of the new block is aligned as well as
* the previous block.
* Block address must start with zeros till size of entity_size.
*/
if ((next_block_start & ((1ULL << block_shift) - 1ULL)) != 0)
/*
* It is not as well aligned as the previous block-reduce the
* mtt size accordingly. Here we take the last right bit which
* is 1.
*/
block_shift = alignment_of(next_block_start);
/*
* Check whether the alignment of the end of previous block - is it
* aligned as well as the start of the block
*/
if (((current_block_end) & ((1ULL << block_shift) - 1ULL)) != 0)
/*
* It is not as well aligned as the start of the block -
* reduce the mtt size accordingly.
*/
block_shift = alignment_of(current_block_end);
return block_shift;
}
int mlx4_ib_umem_write_mtt(struct mlx4_ib_dev *dev, struct mlx4_mtt *mtt,
struct ib_umem *umem)
{
@@ -245,130 +206,6 @@ int mlx4_ib_umem_write_mtt(struct mlx4_ib_dev *dev, struct mlx4_mtt *mtt,
return err;
}
/*
* Calculate optimal mtt size based on contiguous pages.
* Function will return also the number of pages that are not aligned to the
* calculated mtt_size to be added to total number of pages. For that we should
* check the first chunk length & last chunk length and if not aligned to
* mtt_size we should increment the non_aligned_pages number. All chunks in the
* middle already handled as part of mtt shift calculation for both their start
* & end addresses.
*/
int mlx4_ib_umem_calc_optimal_mtt_size(struct ib_umem *umem, u64 start_va,
int *num_of_mtts)
{
u64 block_shift = MLX4_MAX_MTT_SHIFT;
u64 min_shift = PAGE_SHIFT;
u64 last_block_aligned_end = 0;
u64 current_block_start = 0;
u64 first_block_start = 0;
u64 current_block_len = 0;
u64 last_block_end = 0;
struct scatterlist *sg;
u64 current_block_end;
u64 misalignment_bits;
u64 next_block_start;
u64 total_len = 0;
int i;
*num_of_mtts = ib_umem_num_dma_blocks(umem, PAGE_SIZE);
for_each_sgtable_dma_sg(&umem->sgt_append.sgt, sg, i) {
/*
* Initialization - save the first chunk start as the
* current_block_start - block means contiguous pages.
*/
if (current_block_len == 0 && current_block_start == 0) {
current_block_start = sg_dma_address(sg);
first_block_start = current_block_start;
/*
* Find the bits that are different between the physical
* address and the virtual address for the start of the
* MR.
* umem_get aligned the start_va to a page boundary.
* Therefore, we need to align the start va to the same
* boundary.
* misalignment_bits is needed to handle the case of a
* single memory region. In this case, the rest of the
* logic will not reduce the block size. If we use a
* block size which is bigger than the alignment of the
* misalignment bits, we might use the virtual page
* number instead of the physical page number, resulting
* in access to the wrong data.
*/
misalignment_bits =
(start_va & (~(((u64)(PAGE_SIZE)) - 1ULL))) ^
current_block_start;
block_shift = min(alignment_of(misalignment_bits),
block_shift);
}
/*
* Go over the scatter entries and check if they continue the
* previous scatter entry.
*/
next_block_start = sg_dma_address(sg);
current_block_end = current_block_start + current_block_len;
/* If we have a split (non-contig.) between two blocks */
if (current_block_end != next_block_start) {
block_shift = mlx4_ib_umem_calc_block_mtt
(next_block_start,
current_block_end,
block_shift);
/*
* If we reached the minimum shift for 4k page we stop
* the loop.
*/
if (block_shift <= min_shift)
goto end;
/*
* If not saved yet we are in first block - we save the
* length of first block to calculate the
* non_aligned_pages number at the end.
*/
total_len += current_block_len;
/* Start a new block */
current_block_start = next_block_start;
current_block_len = sg_dma_len(sg);
continue;
}
/* The scatter entry is another part of the current block,
* increase the block size.
* An entry in the scatter can be larger than 4k (page) as of
* dma mapping which merge some blocks together.
*/
current_block_len += sg_dma_len(sg);
}
/* Account for the last block in the total len */
total_len += current_block_len;
/* Add to the first block the misalignment that it suffers from. */
total_len += (first_block_start & ((1ULL << block_shift) - 1ULL));
last_block_end = current_block_start + current_block_len;
last_block_aligned_end = round_up(last_block_end, 1ULL << block_shift);
total_len += (last_block_aligned_end - last_block_end);
if (total_len & ((1ULL << block_shift) - 1ULL))
pr_warn("misaligned total length detected (%llu, %llu)!",
total_len, block_shift);
*num_of_mtts = total_len >> block_shift;
end:
if (block_shift < min_shift) {
/*
* If shift is less than the min we set a warning and return the
* min shift.
*/
pr_warn("umem_calc_optimal_mtt_size - unexpected shift %lld\n", block_shift);
block_shift = min_shift;
}
return block_shift;
}
static struct ib_umem *mlx4_get_umem_mr(struct ib_device *device, u64 start,
u64 length, int access_flags)
{
@@ -424,6 +261,10 @@ struct ib_mr *mlx4_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
}
shift = mlx4_ib_umem_calc_optimal_mtt_size(mr->umem, start, &n);
if (shift < 0) {
err = shift;
goto err_umem;
}
err = mlx4_mr_alloc(dev->dev, to_mpd(pd)->pdn, virt_addr, length,
convert_access(access_flags), n, shift, &mr->mmr);

12
drivers/infiniband/hw/mlx4/qp.c
View File

@@ -925,8 +925,12 @@ static int create_rq(struct ib_pd *pd, struct ib_qp_init_attr *init_attr,
}
shift = mlx4_ib_umem_calc_optimal_mtt_size(qp->umem, 0, &n);
err = mlx4_mtt_init(dev->dev, n, shift, &qp->mtt);
if (shift < 0) {
err = shift;
goto err_buf;
}
err = mlx4_mtt_init(dev->dev, n, shift, &qp->mtt);
if (err)
goto err_buf;
@@ -1108,8 +1112,12 @@ static int create_qp_common(struct ib_pd *pd, struct ib_qp_init_attr *init_attr,
}
shift = mlx4_ib_umem_calc_optimal_mtt_size(qp->umem, 0, &n);
err = mlx4_mtt_init(dev->dev, n, shift, &qp->mtt);
if (shift < 0) {
err = shift;
goto err_buf;
}
err = mlx4_mtt_init(dev->dev, n, shift, &qp->mtt);
if (err)
goto err_buf;