diff options
| author | Jason Gunthorpe <jgg@nvidia.com> | 2020-09-04 19:41:44 -0300 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@nvidia.com> | 2020-09-09 15:33:17 -0300 |
| commit | 3361c29e9279e682c0e9a7d7461b4e3bbc77830b (patch) | |
| tree | a4c62c20f951a7cb9f009b0716f25d74b5f4fe81 | |
| parent | 10c75ccb54e4fe548cb16d7ed426d7d709e6ae76 (diff) | |
RDMA/umem: Use simpler logic for ib_umem_find_best_pgsz()
The calculation in rdma_find_pg_bit() is fairly complicated, and the
function is never called anywhere else. Inline a simpler version into
ib_umem_find_best_pgsz()
Link: https://lore.kernel.org/r/3-v2-270386b7e60b+28f4-umem_1_jgg@nvidia.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
| -rw-r--r-- | drivers/infiniband/core/umem.c | 11 | ||||
| -rw-r--r-- | include/rdma/ib_verbs.h | 24 |
2 files changed, 8 insertions, 27 deletions
diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 1d0599997d0f..fb7630e7aac3 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -39,6 +39,7 @@ #include <linux/export.h> #include <linux/slab.h> #include <linux/pagemap.h> +#include <linux/count_zeros.h> #include <rdma/ib_umem_odp.h> #include "uverbs.h" @@ -146,7 +147,6 @@ unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem, unsigned long virt) { struct scatterlist *sg; - unsigned int best_pg_bit; unsigned long va, pgoff; dma_addr_t mask; int i; @@ -186,9 +186,14 @@ unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem, mask |= va; pgoff = 0; } - best_pg_bit = rdma_find_pg_bit(mask, pgsz_bitmap); - return BIT_ULL(best_pg_bit); + /* The mask accumulates 1's in each position where the VA and physical + * address differ, thus the length of trailing 0 is the largest page + * size that can pass the VA through to the physical. + */ + if (mask) + pgsz_bitmap &= GENMASK(count_trailing_zeros(mask), 0); + return rounddown_pow_of_two(pgsz_bitmap); } EXPORT_SYMBOL(ib_umem_find_best_pgsz); diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index 29a36ec662b5..97658d706aa1 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -3336,30 +3336,6 @@ static inline bool rdma_cap_read_inv(struct ib_device *dev, u32 port_num) } /** - * rdma_find_pg_bit - Find page bit given address and HW supported page sizes - * - * @addr: address - * @pgsz_bitmap: bitmap of HW supported page sizes - */ -static inline unsigned int rdma_find_pg_bit(unsigned long addr, - unsigned long pgsz_bitmap) -{ - unsigned long align; - unsigned long pgsz; - - align = addr & -addr; - - /* Find page bit such that addr is aligned to the highest supported - * HW page size - */ - pgsz = pgsz_bitmap & ~(-align << 1); - if (!pgsz) - return __ffs(pgsz_bitmap); - - return __fls(pgsz); -} - -/** * rdma_core_cap_opa_port - Return whether the RDMA Port is OPA or not. * @device: Device * @port_num: 1 based Port number |