Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

[linux.git] / tools / lib / bpf / libbpf.c

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 2233f919dd88fe4d18302594ae2605b749e91eaa..e0276520171b952888c3b2c41c23e0d1a7804edf 100644 (file)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -187,7 +187,6 @@ struct bpf_program {
        bpf_program_clear_priv_t clear_priv;
 
        enum bpf_attach_type expected_attach_type;
-       int btf_fd;
        void *func_info;
        __u32 func_info_rec_size;
        __u32 func_info_cnt;
@@ -318,7 +317,6 @@ void bpf_program__unload(struct bpf_program *prog)
        prog->instances.nr = -1;
        zfree(&prog->instances.fds);
 
-       zclose(prog->btf_fd);
        zfree(&prog->func_info);
        zfree(&prog->line_info);
 }
@@ -397,7 +395,6 @@ bpf_program__init(void *data, size_t size, char *section_name, int idx,
        prog->instances.fds = NULL;
        prog->instances.nr = -1;
        prog->type = BPF_PROG_TYPE_UNSPEC;
-       prog->btf_fd = -1;
 
        return 0;
 errout:
@@ -2296,9 +2293,6 @@ bpf_program_reloc_btf_ext(struct bpf_program *prog, struct bpf_object *obj,
                prog->line_info_rec_size = btf_ext__line_info_rec_size(obj->btf_ext);
        }
 
-       if (!insn_offset)
-               prog->btf_fd = btf__fd(obj->btf);
-
        return 0;
 }
 
@@ -3366,7 +3360,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
        char *cp, errmsg[STRERR_BUFSIZE];
        int log_buf_size = BPF_LOG_BUF_SIZE;
        char *log_buf;
-       int ret;
+       int btf_fd, ret;
 
        if (!insns || !insns_cnt)
                return -EINVAL;
@@ -3381,7 +3375,12 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
        load_attr.license = license;
        load_attr.kern_version = kern_version;
        load_attr.prog_ifindex = prog->prog_ifindex;
-       load_attr.prog_btf_fd = prog->btf_fd >= 0 ? prog->btf_fd : 0;
+       /* if .BTF.ext was loaded, kernel supports associated BTF for prog */
+       if (prog->obj->btf_ext)
+               btf_fd = bpf_object__btf_fd(prog->obj);
+       else
+               btf_fd = -1;
+       load_attr.prog_btf_fd = btf_fd >= 0 ? btf_fd : 0;
        load_attr.func_info = prog->func_info;
        load_attr.func_info_rec_size = prog->func_info_rec_size;
        load_attr.func_info_cnt = prog->func_info_cnt;
@@ -5903,13 +5902,15 @@ int libbpf_num_possible_cpus(void)
        static const char *fcpu = "/sys/devices/system/cpu/possible";
        int len = 0, n = 0, il = 0, ir = 0;
        unsigned int start = 0, end = 0;
+       int tmp_cpus = 0;
        static int cpus;
        char buf[128];
        int error = 0;
        int fd = -1;
 
-       if (cpus > 0)
-               return cpus;
+       tmp_cpus = READ_ONCE(cpus);
+       if (tmp_cpus > 0)
+               return tmp_cpus;
 
        fd = open(fcpu, O_RDONLY);
        if (fd < 0) {
@@ -5932,7 +5933,7 @@ int libbpf_num_possible_cpus(void)
        }
        buf[len] = '\0';
 
-       for (ir = 0, cpus = 0; ir <= len; ir++) {
+       for (ir = 0, tmp_cpus = 0; ir <= len; ir++) {
                /* Each sub string separated by ',' has format \d+-\d+ or \d+ */
                if (buf[ir] == ',' || buf[ir] == '\0') {
                        buf[ir] = '\0';
@@ -5944,13 +5945,15 @@ int libbpf_num_possible_cpus(void)
                        } else if (n == 1) {
                                end = start;
                        }
-                       cpus += end - start + 1;
+                       tmp_cpus += end - start + 1;
                        il = ir + 1;
                }
        }
-       if (cpus <= 0) {
-               pr_warning("Invalid #CPUs %d from %s\n", cpus, fcpu);
+       if (tmp_cpus <= 0) {
+               pr_warning("Invalid #CPUs %d from %s\n", tmp_cpus, fcpu);
                return -EINVAL;
        }
-       return cpus;
+
+       WRITE_ONCE(cpus, tmp_cpus);
+       return tmp_cpus;
 }