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Diffstat (limited to 'tools/lib/bpf/libbpf.c')
-rw-r--r--tools/lib/bpf/libbpf.c67
1 files changed, 41 insertions, 26 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 794dd5064ae8..2b57d7ea7836 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -20,6 +20,7 @@
#include <inttypes.h>
#include <string.h>
#include <unistd.h>
+#include <endian.h>
#include <fcntl.h>
#include <errno.h>
#include <asm/unistd.h>
@@ -181,7 +182,6 @@ 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;
@@ -312,7 +312,6 @@ 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);
}
@@ -391,7 +390,6 @@ 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:
@@ -612,10 +610,10 @@ errout:
static int bpf_object__check_endianness(struct bpf_object *obj)
{
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#if __BYTE_ORDER == __LITTLE_ENDIAN
if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2LSB)
return 0;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#elif __BYTE_ORDER == __BIG_ENDIAN
if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2MSB)
return 0;
#else
@@ -1377,8 +1375,13 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj)
if (!has_datasec && kind == BTF_KIND_VAR) {
/* replace VAR with INT */
t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0);
- t->size = sizeof(int);
- *(int *)(t+1) = BTF_INT_ENC(0, 0, 32);
+ /*
+ * using size = 1 is the safest choice, 4 will be too
+ * big and cause kernel BTF validation failure if
+ * original variable took less than 4 bytes
+ */
+ t->size = 1;
+ *(int *)(t+1) = BTF_INT_ENC(0, 0, 8);
} else if (!has_datasec && kind == BTF_KIND_DATASEC) {
/* replace DATASEC with STRUCT */
struct btf_var_secinfo *v = (void *)(t + 1);
@@ -1500,6 +1503,12 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj)
BTF_ELF_SEC, err);
btf__free(obj->btf);
obj->btf = NULL;
+ /* btf_ext can't exist without btf, so free it as well */
+ if (obj->btf_ext) {
+ btf_ext__free(obj->btf_ext);
+ obj->btf_ext = NULL;
+ }
+
if (bpf_object__is_btf_mandatory(obj))
return err;
}
@@ -2276,9 +2285,6 @@ 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;
}
@@ -2451,7 +2457,7 @@ 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;
@@ -2466,7 +2472,12 @@ 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;
@@ -4507,13 +4518,13 @@ struct perf_buffer *perf_buffer__new(int map_fd, size_t page_cnt,
const struct perf_buffer_opts *opts)
{
struct perf_buffer_params p = {};
- struct perf_event_attr attr = {
- .config = PERF_COUNT_SW_BPF_OUTPUT,
- .type = PERF_TYPE_SOFTWARE,
- .sample_type = PERF_SAMPLE_RAW,
- .sample_period = 1,
- .wakeup_events = 1,
- };
+ struct perf_event_attr attr = { 0, };
+
+ attr.config = PERF_COUNT_SW_BPF_OUTPUT,
+ attr.type = PERF_TYPE_SOFTWARE;
+ attr.sample_type = PERF_SAMPLE_RAW;
+ attr.sample_period = 1;
+ attr.wakeup_events = 1;
p.attr = &attr;
p.sample_cb = opts ? opts->sample_cb : NULL;
@@ -4988,13 +4999,15 @@ 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) {
@@ -5017,7 +5030,7 @@ 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';
@@ -5029,13 +5042,15 @@ 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;
}