From: Alexei Starovoitov <ast@kernel.org>
To: <davem@davemloft.net>
Cc: <daniel@iogearbox.net>, <netdev@vger.kernel.org>,
<bpf@vger.kernel.org>, <kernel-team@fb.com>
Subject: [PATCH v2 bpf-next 2/2] libbpf: add support for prog_tracing
Date: Wed, 30 Oct 2019 15:32:12 -0700 [thread overview]
Message-ID: <20191030223212.953010-3-ast@kernel.org> (raw)
In-Reply-To: <20191030223212.953010-1-ast@kernel.org>
Cleanup libbpf from expected_attach_type == attach_btf_id hack
and introduce BPF_PROG_TYPE_TRACING.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
---
tools/include/uapi/linux/bpf.h | 2 +
tools/lib/bpf/bpf.c | 8 ++--
tools/lib/bpf/bpf.h | 5 ++-
tools/lib/bpf/libbpf.c | 79 ++++++++++++++++++++++++----------
tools/lib/bpf/libbpf.h | 2 +
tools/lib/bpf/libbpf.map | 2 +
tools/lib/bpf/libbpf_probes.c | 1 +
7 files changed, 71 insertions(+), 28 deletions(-)
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 4af8b0819a32..a6bf19dabaab 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -173,6 +173,7 @@ enum bpf_prog_type {
BPF_PROG_TYPE_CGROUP_SYSCTL,
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
BPF_PROG_TYPE_CGROUP_SOCKOPT,
+ BPF_PROG_TYPE_TRACING,
};
enum bpf_attach_type {
@@ -199,6 +200,7 @@ enum bpf_attach_type {
BPF_CGROUP_UDP6_RECVMSG,
BPF_CGROUP_GETSOCKOPT,
BPF_CGROUP_SETSOCKOPT,
+ BPF_TRACE_RAW_TP,
__MAX_BPF_ATTACH_TYPE
};
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 79046067720f..ca0d635b1d5e 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -228,9 +228,10 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
memset(&attr, 0, sizeof(attr));
attr.prog_type = load_attr->prog_type;
attr.expected_attach_type = load_attr->expected_attach_type;
- if (attr.prog_type == BPF_PROG_TYPE_RAW_TRACEPOINT)
- /* expected_attach_type is ignored for tracing progs */
- attr.attach_btf_id = attr.expected_attach_type;
+ if (attr.prog_type == BPF_PROG_TYPE_TRACING)
+ attr.attach_btf_id = load_attr->attach_btf_id;
+ else
+ attr.prog_ifindex = load_attr->prog_ifindex;
attr.insn_cnt = (__u32)load_attr->insns_cnt;
attr.insns = ptr_to_u64(load_attr->insns);
attr.license = ptr_to_u64(load_attr->license);
@@ -245,7 +246,6 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
}
attr.kern_version = load_attr->kern_version;
- attr.prog_ifindex = load_attr->prog_ifindex;
attr.prog_btf_fd = load_attr->prog_btf_fd;
attr.func_info_rec_size = load_attr->func_info_rec_size;
attr.func_info_cnt = load_attr->func_info_cnt;
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 0db01334740f..1c53bc5b4b3c 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -78,7 +78,10 @@ struct bpf_load_program_attr {
size_t insns_cnt;
const char *license;
__u32 kern_version;
- __u32 prog_ifindex;
+ union {
+ __u32 prog_ifindex;
+ __u32 attach_btf_id;
+ };
__u32 prog_btf_fd;
__u32 func_info_rec_size;
const void *func_info;
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 5d15cc4dfcd6..c80f316f1320 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -188,6 +188,7 @@ struct bpf_program {
bpf_program_clear_priv_t clear_priv;
enum bpf_attach_type expected_attach_type;
+ __u32 attach_btf_id;
void *func_info;
__u32 func_info_rec_size;
__u32 func_info_cnt;
@@ -3446,6 +3447,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
load_attr.line_info_cnt = prog->line_info_cnt;
load_attr.log_level = prog->log_level;
load_attr.prog_flags = prog->prog_flags;
+ load_attr.attach_btf_id = prog->attach_btf_id;
retry_load:
log_buf = malloc(log_buf_size);
@@ -3607,6 +3609,8 @@ bpf_object__load_progs(struct bpf_object *obj, int log_level)
return 0;
}
+static int libbpf_attach_btf_id_by_name(const char *name, __u32 *btf_id);
+
static struct bpf_object *
__bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
struct bpf_object_open_opts *opts)
@@ -3656,6 +3660,7 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
bpf_object__for_each_program(prog, obj) {
enum bpf_prog_type prog_type;
enum bpf_attach_type attach_type;
+ __u32 btf_id;
err = libbpf_prog_type_by_name(prog->section_name, &prog_type,
&attach_type);
@@ -3667,6 +3672,12 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
bpf_program__set_type(prog, prog_type);
bpf_program__set_expected_attach_type(prog, attach_type);
+ if (prog_type == BPF_PROG_TYPE_TRACING) {
+ err = libbpf_attach_btf_id_by_name(prog->section_name, &btf_id);
+ if (err)
+ goto out;
+ prog->attach_btf_id = btf_id;
+ }
}
return obj;
@@ -4518,6 +4529,7 @@ BPF_PROG_TYPE_FNS(tracepoint, BPF_PROG_TYPE_TRACEPOINT);
BPF_PROG_TYPE_FNS(raw_tracepoint, BPF_PROG_TYPE_RAW_TRACEPOINT);
BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP);
BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT);
+BPF_PROG_TYPE_FNS(tracing, BPF_PROG_TYPE_TRACING);
enum bpf_attach_type
bpf_program__get_expected_attach_type(struct bpf_program *prog)
@@ -4546,7 +4558,8 @@ void bpf_program__set_expected_attach_type(struct bpf_program *prog,
BPF_PROG_SEC_IMPL(string, ptype, eatype, 1, 0, eatype)
/* Programs that use BTF to identify attach point */
-#define BPF_PROG_BTF(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, 0, 1, 0)
+#define BPF_PROG_BTF(string, ptype, eatype) \
+ BPF_PROG_SEC_IMPL(string, ptype, eatype, 0, 1, 0)
/* Programs that can be attached but attach type can't be identified by section
* name. Kept for backward compatibility.
@@ -4573,7 +4586,8 @@ static const struct {
BPF_PROG_SEC("tp/", BPF_PROG_TYPE_TRACEPOINT),
BPF_PROG_SEC("raw_tracepoint/", BPF_PROG_TYPE_RAW_TRACEPOINT),
BPF_PROG_SEC("raw_tp/", BPF_PROG_TYPE_RAW_TRACEPOINT),
- BPF_PROG_BTF("tp_btf/", BPF_PROG_TYPE_RAW_TRACEPOINT),
+ BPF_PROG_BTF("tp_btf/", BPF_PROG_TYPE_TRACING,
+ BPF_TRACE_RAW_TP),
BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP),
BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT),
BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN),
@@ -4678,27 +4692,6 @@ int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
continue;
*prog_type = section_names[i].prog_type;
*expected_attach_type = section_names[i].expected_attach_type;
- if (section_names[i].is_attach_btf) {
- struct btf *btf = bpf_core_find_kernel_btf();
- char raw_tp_btf_name[128] = "btf_trace_";
- char *dst = raw_tp_btf_name + sizeof("btf_trace_") - 1;
- int ret;
-
- if (IS_ERR(btf)) {
- pr_warn("vmlinux BTF is not found\n");
- return -EINVAL;
- }
- /* prepend "btf_trace_" prefix per kernel convention */
- strncat(dst, name + section_names[i].len,
- sizeof(raw_tp_btf_name) - sizeof("btf_trace_"));
- ret = btf__find_by_name(btf, raw_tp_btf_name);
- btf__free(btf);
- if (ret <= 0) {
- pr_warn("%s is not found in vmlinux BTF\n", dst);
- return -EINVAL;
- }
- *expected_attach_type = ret;
- }
return 0;
}
pr_warn("failed to guess program type based on ELF section name '%s'\n", name);
@@ -4711,6 +4704,46 @@ int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
return -ESRCH;
}
+#define BTF_PREFIX "btf_trace_"
+static int libbpf_attach_btf_id_by_name(const char *name, __u32 *btf_id)
+{
+ struct btf *btf = bpf_core_find_kernel_btf();
+ char raw_tp_btf_name[128] = BTF_PREFIX;
+ char *dst = raw_tp_btf_name + sizeof(BTF_PREFIX) - 1;
+ int ret, i, err = -EINVAL;
+
+ if (IS_ERR(btf)) {
+ pr_warn("vmlinux BTF is not found\n");
+ return -EINVAL;
+ }
+
+ if (!name)
+ goto out;
+
+ for (i = 0; i < ARRAY_SIZE(section_names); i++) {
+ if (!section_names[i].is_attach_btf)
+ continue;
+ if (strncmp(name, section_names[i].sec, section_names[i].len))
+ continue;
+ /* prepend "btf_trace_" prefix per kernel convention */
+ strncat(dst, name + section_names[i].len,
+ sizeof(raw_tp_btf_name) - sizeof(BTF_PREFIX));
+ ret = btf__find_by_name(btf, raw_tp_btf_name);
+ if (ret <= 0) {
+ pr_warn("%s is not found in vmlinux BTF\n", dst);
+ goto out;
+ }
+ *btf_id = ret;
+ err = 0;
+ goto out;
+ }
+ pr_warn("failed to identify btf_id based on ELF section name '%s'\n", name);
+ err = -ESRCH;
+out:
+ btf__free(btf);
+ return err;
+}
+
int libbpf_attach_type_by_name(const char *name,
enum bpf_attach_type *attach_type)
{
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index c63e2ff84abc..2b126ee5e173 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -307,6 +307,7 @@ LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
+LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
@@ -326,6 +327,7 @@ LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
+LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
/*
* No need for __attribute__((packed)), all members of 'bpf_map_def'
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index d1473ea4d7a5..69dded5af00b 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -197,4 +197,6 @@ LIBBPF_0.0.6 {
bpf_object__open_mem;
bpf_program__get_expected_attach_type;
bpf_program__get_type;
+ bpf_program__is_tracing;
+ bpf_program__set_tracing;
} LIBBPF_0.0.5;
diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c
index 4b0b0364f5fc..a9eb8b322671 100644
--- a/tools/lib/bpf/libbpf_probes.c
+++ b/tools/lib/bpf/libbpf_probes.c
@@ -102,6 +102,7 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns,
case BPF_PROG_TYPE_FLOW_DISSECTOR:
case BPF_PROG_TYPE_CGROUP_SYSCTL:
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+ case BPF_PROG_TYPE_TRACING:
default:
break;
}
--
2.17.1
next prev parent reply other threads:[~2019-10-30 22:32 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-30 22:32 [PATCH v2 bpf-next 0/2] bpf: cleanup BTF-enabled raw_tp Alexei Starovoitov
2019-10-30 22:32 ` [PATCH v2 bpf-next 1/2] bpf: replace prog_raw_tp+btf_id with prog_tracing Alexei Starovoitov
2019-10-31 0:18 ` Martin Lau
2019-10-31 23:20 ` Daniel Borkmann
2019-10-31 23:36 ` Alexei Starovoitov
2019-11-01 1:03 ` Daniel Borkmann
2019-10-30 22:32 ` Alexei Starovoitov [this message]
2019-10-31 0:22 ` [PATCH v2 bpf-next 2/2] libbpf: add support for prog_tracing Martin Lau
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