diff options
| -rw-r--r-- | src/include/liburing.h | 3 | ||||
| -rw-r--r-- | src/liburing.map | 6 | ||||
| -rw-r--r-- | src/setup.c | 120 |
3 files changed, 129 insertions, 0 deletions
diff --git a/src/include/liburing.h b/src/include/liburing.h index 5b96e02..a111c54 100644 --- a/src/include/liburing.h +++ b/src/include/liburing.h @@ -655,6 +655,9 @@ static inline int io_uring_wait_cqe(struct io_uring *ring, return io_uring_wait_cqe_nr(ring, cqe_ptr, 1); } +ssize_t io_uring_mlock_size(unsigned entries, unsigned flags); +ssize_t io_uring_mlock_size_params(unsigned entries, struct io_uring_params *p); + #ifdef __cplusplus } #endif diff --git a/src/liburing.map b/src/liburing.map index dfdc7ba..012ac4e 100644 --- a/src/liburing.map +++ b/src/liburing.map @@ -31,3 +31,9 @@ LIBURING_2.0 { local: *; }; + +LIBURING_2.1 { + global: + io_uring_mlock_size_params; + io_uring_mlock_size; +} LIBURING_2.0; diff --git a/src/setup.c b/src/setup.c index c01a933..111db61 100644 --- a/src/setup.c +++ b/src/setup.c @@ -217,3 +217,123 @@ void io_uring_free_probe(struct io_uring_probe *probe) { free(probe); } + +static int __fls(int x) +{ + int r = 32; + + if (!x) + return 0; + if (!(x & 0xffff0000u)) { + x <<= 16; + r -= 16; + } + if (!(x & 0xff000000u)) { + x <<= 8; + r -= 8; + } + if (!(x & 0xf0000000u)) { + x <<= 4; + r -= 4; + } + if (!(x & 0xc0000000u)) { + x <<= 2; + r -= 2; + } + if (!(x & 0x80000000u)) { + x <<= 1; + r -= 1; + } + return r; +} + +static unsigned roundup_pow2(unsigned depth) +{ + return 1UL << __fls(depth - 1); +} + +static size_t npages(size_t size, unsigned page_size) +{ + size--; + size /= page_size; + return __fls(size); +} + +#define KRING_SIZE 320 + +static size_t rings_size(unsigned entries, unsigned cq_entries, unsigned page_size) +{ + size_t pages, sq_size, cq_size; + + cq_size = KRING_SIZE; + cq_size += cq_entries * sizeof(struct io_uring_cqe); + cq_size = (cq_size + 63) & ~63UL; + pages = (size_t) 1 << npages(cq_size, page_size); + + sq_size = sizeof(struct io_uring_sqe) * entries; + pages += (size_t) 1 << npages(sq_size, page_size); + return pages * page_size; +} + +#define KERN_MAX_ENTRIES 32768 +#define KERN_MAX_CQ_ENTRIES (2 * KERN_MAX_ENTRIES) + +ssize_t io_uring_mlock_size_params(unsigned entries, struct io_uring_params *p) +{ + struct io_uring_params lp = { }; + struct io_uring ring; + unsigned cq_entries; + long page_size; + ssize_t ret; + + ret = io_uring_queue_init_params(entries, &ring, &lp); + if (ret < 0) + return ret; + + io_uring_queue_exit(&ring); + + /* + * Native workers imply using cgroup memory accounting, and hence no + * memlock memory is needed for the ring allocations. + */ + if (lp.features & IORING_FEAT_NATIVE_WORKERS) + return 0; + + if (!entries) + return -EINVAL; + if (entries > KERN_MAX_ENTRIES) { + if (!(p->flags & IORING_SETUP_CLAMP)) + return -EINVAL; + entries = KERN_MAX_ENTRIES; + } + + entries = roundup_pow2(entries); + if (p->flags & IORING_SETUP_CQSIZE) { + if (!p->cq_entries) + return -EINVAL; + cq_entries = p->cq_entries; + if (cq_entries > KERN_MAX_CQ_ENTRIES) { + if (!(p->flags & IORING_SETUP_CLAMP)) + return -EINVAL; + cq_entries = KERN_MAX_CQ_ENTRIES; + } + cq_entries = roundup_pow2(cq_entries); + if (cq_entries < entries) + return -EINVAL; + } else { + cq_entries = 2 * entries; + } + + page_size = sysconf(_SC_PAGESIZE); + if (page_size < 0) + page_size = 4096; + + return rings_size(entries, cq_entries, page_size); +} + +ssize_t io_uring_mlock_size(unsigned entries, unsigned flags) +{ + struct io_uring_params p = { .flags = flags, }; + + return io_uring_mlock_size_params(entries, &p); +} |