We have relaxed the limitation of 1024-page batches for both sleepable and nonsleepable arena allocations by removing the intermediate page array. Add a test to confirm that large allocations succeed for both. Signed-off-by: Emil Tsalapatis --- .../bpf/progs/verifier_arena_large.c | 64 +++++++++++++++---- 1 file changed, 50 insertions(+), 14 deletions(-) diff --git a/tools/testing/selftests/bpf/progs/verifier_arena_large.c b/tools/testing/selftests/bpf/progs/verifier_arena_large.c index 6ab8730d4878..dbdea14ca76f 100644 --- a/tools/testing/selftests/bpf/progs/verifier_arena_large.c +++ b/tools/testing/selftests/bpf/progs/verifier_arena_large.c @@ -10,6 +10,9 @@ #include #define ARENA_SIZE (1ull << 32) +#define LARGE_PAGE_CNT 1025 + +volatile int zero = 0; struct { __uint(type, BPF_MAP_TYPE_ARENA); @@ -284,6 +287,7 @@ int big_alloc2(void *ctx) return 0; } +/* Nonsleepable because it binds to a socket program. */ SEC("socket") __success __retval(0) int big_alloc3(void *ctx) @@ -291,24 +295,56 @@ int big_alloc3(void *ctx) #if defined(__BPF_FEATURE_ADDR_SPACE_CAST) char __arena *pages; u64 i; + int err = 0; - /* - * Allocate 2051 pages in one go to check how kmalloc_nolock() handles large requests. - * Since kmalloc_nolock() can allocate up to 1024 struct page * at a time, this call should - * result in three batches: two batches of 1024 pages each, followed by a final batch of 3 - * pages. - */ - pages = bpf_arena_alloc_pages(&arena, NULL, 2051, NUMA_NO_NODE, 0); + /* Verify that a nonsleepable allocation larger than 1024 pages succeeds. */ + pages = bpf_arena_alloc_pages(&arena, NULL, LARGE_PAGE_CNT, NUMA_NO_NODE, 0); if (!pages) - return 0; + return 1; + + for (i = zero; i < LARGE_PAGE_CNT && can_loop; i++) + pages[i * PAGE_SIZE] = 123; + + for (i = zero; i < LARGE_PAGE_CNT && can_loop; i++) { + if (pages[i * PAGE_SIZE] == 123) + continue; + err = 2; + break; + } + + bpf_arena_free_pages(&arena, pages, LARGE_PAGE_CNT); + return err; +#endif + return 0; +} - bpf_for(i, 0, 2051) - pages[i * PAGE_SIZE] = 123; - bpf_for(i, 0, 2051) - if (pages[i * PAGE_SIZE] != 123) - return i; +/* SYSCALL programs are always sleepable. */ +SEC("syscall") +__success __retval(0) +int big_alloc4(void *ctx) +{ +#if defined(__BPF_FEATURE_ADDR_SPACE_CAST) + char __arena *pages; + u64 i; + int err = 0; + + /* Verify that a sleepable allocation larger than 1024 pages succeeds. */ + pages = bpf_arena_alloc_pages(&arena, NULL, LARGE_PAGE_CNT, NUMA_NO_NODE, 0); + if (!pages) + return 1; + + for (i = zero; i < LARGE_PAGE_CNT && can_loop; i++) + pages[i * PAGE_SIZE] = 123; + + for (i = zero; i < LARGE_PAGE_CNT && can_loop; i++) { + if (pages[i * PAGE_SIZE] == 123) + continue; + err = 2; + break; + } - bpf_arena_free_pages(&arena, pages, 2051); + bpf_arena_free_pages(&arena, pages, LARGE_PAGE_CNT); + return err; #endif return 0; } -- 2.52.0