From c317ab71facc2cd0a94145973318a4c914e11acc Mon Sep 17 00:00:00 2001 From: Menglong Dong Date: Mon, 25 Apr 2022 21:32:47 +0800 Subject: bpf: Compute map_btf_id during build time For now, the field 'map_btf_id' in 'struct bpf_map_ops' for all map types are computed during vmlinux-btf init: btf_parse_vmlinux() -> btf_vmlinux_map_ids_init() It will lookup the btf_type according to the 'map_btf_name' field in 'struct bpf_map_ops'. This process can be done during build time, thanks to Jiri's resolve_btfids. selftest of map_ptr has passed: $96 map_ptr:OK Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED Reported-by: kernel test robot Signed-off-by: Menglong Dong Signed-off-by: Alexei Starovoitov --- kernel/bpf/arraymap.c | 26 ++++++++------------------ 1 file changed, 8 insertions(+), 18 deletions(-) (limited to 'kernel/bpf/arraymap.c') diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index c3de63ce574e..b3bf31fd9458 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -11,6 +11,7 @@ #include #include #include +#include #include "map_in_map.h" @@ -690,7 +691,7 @@ static int bpf_for_each_array_elem(struct bpf_map *map, bpf_callback_t callback_ return num_elems; } -static int array_map_btf_id; +BTF_ID_LIST_SINGLE(array_map_btf_ids, struct, bpf_array) const struct bpf_map_ops array_map_ops = { .map_meta_equal = array_map_meta_equal, .map_alloc_check = array_map_alloc_check, @@ -711,12 +712,10 @@ const struct bpf_map_ops array_map_ops = { .map_update_batch = generic_map_update_batch, .map_set_for_each_callback_args = map_set_for_each_callback_args, .map_for_each_callback = bpf_for_each_array_elem, - .map_btf_name = "bpf_array", - .map_btf_id = &array_map_btf_id, + .map_btf_id = &array_map_btf_ids[0], .iter_seq_info = &iter_seq_info, }; -static int percpu_array_map_btf_id; const struct bpf_map_ops percpu_array_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = array_map_alloc_check, @@ -732,8 +731,7 @@ const struct bpf_map_ops percpu_array_map_ops = { .map_update_batch = generic_map_update_batch, .map_set_for_each_callback_args = map_set_for_each_callback_args, .map_for_each_callback = bpf_for_each_array_elem, - .map_btf_name = "bpf_array", - .map_btf_id = &percpu_array_map_btf_id, + .map_btf_id = &array_map_btf_ids[0], .iter_seq_info = &iter_seq_info, }; @@ -1112,7 +1110,6 @@ static void prog_array_map_free(struct bpf_map *map) * Thus, prog_array_map cannot be used as an inner_map * and map_meta_equal is not implemented. */ -static int prog_array_map_btf_id; const struct bpf_map_ops prog_array_map_ops = { .map_alloc_check = fd_array_map_alloc_check, .map_alloc = prog_array_map_alloc, @@ -1128,8 +1125,7 @@ const struct bpf_map_ops prog_array_map_ops = { .map_fd_sys_lookup_elem = prog_fd_array_sys_lookup_elem, .map_release_uref = prog_array_map_clear, .map_seq_show_elem = prog_array_map_seq_show_elem, - .map_btf_name = "bpf_array", - .map_btf_id = &prog_array_map_btf_id, + .map_btf_id = &array_map_btf_ids[0], }; static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file, @@ -1218,7 +1214,6 @@ static void perf_event_fd_array_map_free(struct bpf_map *map) fd_array_map_free(map); } -static int perf_event_array_map_btf_id; const struct bpf_map_ops perf_event_array_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = fd_array_map_alloc_check, @@ -1231,8 +1226,7 @@ const struct bpf_map_ops perf_event_array_map_ops = { .map_fd_put_ptr = perf_event_fd_array_put_ptr, .map_release = perf_event_fd_array_release, .map_check_btf = map_check_no_btf, - .map_btf_name = "bpf_array", - .map_btf_id = &perf_event_array_map_btf_id, + .map_btf_id = &array_map_btf_ids[0], }; #ifdef CONFIG_CGROUPS @@ -1255,7 +1249,6 @@ static void cgroup_fd_array_free(struct bpf_map *map) fd_array_map_free(map); } -static int cgroup_array_map_btf_id; const struct bpf_map_ops cgroup_array_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = fd_array_map_alloc_check, @@ -1267,8 +1260,7 @@ const struct bpf_map_ops cgroup_array_map_ops = { .map_fd_get_ptr = cgroup_fd_array_get_ptr, .map_fd_put_ptr = cgroup_fd_array_put_ptr, .map_check_btf = map_check_no_btf, - .map_btf_name = "bpf_array", - .map_btf_id = &cgroup_array_map_btf_id, + .map_btf_id = &array_map_btf_ids[0], }; #endif @@ -1342,7 +1334,6 @@ static int array_of_map_gen_lookup(struct bpf_map *map, return insn - insn_buf; } -static int array_of_maps_map_btf_id; const struct bpf_map_ops array_of_maps_map_ops = { .map_alloc_check = fd_array_map_alloc_check, .map_alloc = array_of_map_alloc, @@ -1355,6 +1346,5 @@ const struct bpf_map_ops array_of_maps_map_ops = { .map_fd_sys_lookup_elem = bpf_map_fd_sys_lookup_elem, .map_gen_lookup = array_of_map_gen_lookup, .map_check_btf = map_check_no_btf, - .map_btf_name = "bpf_array", - .map_btf_id = &array_of_maps_map_btf_id, + .map_btf_id = &array_map_btf_ids[0], }; -- cgit v1.2.3-59-g8ed1b