* [PATCH v3 bpf-next 1/3] bpf: enable BPF_PROG_TEST_RUN for raw_tracepoint
2020-09-23 21:33 [PATCH v3 bpf-next 0/3] enable BPF_PROG_TEST_RUN for raw_tp Song Liu
@ 2020-09-23 21:33 ` Song Liu
2020-09-23 21:33 ` [PATCH v3 bpf-next 2/3] libbpf: introduce bpf_prog_test_run_xattr_opts Song Liu
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Song Liu @ 2020-09-23 21:33 UTC (permalink / raw)
To: netdev, bpf; +Cc: kernel-team, ast, daniel, john.fastabend, kpsingh, Song Liu
Add .test_run for raw_tracepoint. Also, introduce a new feature that runs
the target program on a specific CPU. This is achieved by a new flag in
bpf_attr.test, cpu_plus. For compatibility, cpu_plus == 0 means run the
program on current cpu, cpu_plus > 0 means run the program on cpu with id
(cpu_plus - 1). This feature is needed for BPF programs that handle
perf_event and other percpu resources, as the program can access these
resource locally.
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
---
include/linux/bpf.h | 3 ++
include/uapi/linux/bpf.h | 5 ++
kernel/bpf/syscall.c | 2 +-
kernel/trace/bpf_trace.c | 1 +
net/bpf/test_run.c | 88 ++++++++++++++++++++++++++++++++++
tools/include/uapi/linux/bpf.h | 5 ++
6 files changed, 103 insertions(+), 1 deletion(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index d7c5a6ed87e30..23758c282eb4b 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1376,6 +1376,9 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
const union bpf_attr *kattr,
union bpf_attr __user *uattr);
+int bpf_prog_test_run_raw_tp(struct bpf_prog *prog,
+ const union bpf_attr *kattr,
+ union bpf_attr __user *uattr);
bool btf_ctx_access(int off, int size, enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info);
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index a22812561064a..89acf41913e70 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -566,6 +566,11 @@ union bpf_attr {
*/
__aligned_u64 ctx_in;
__aligned_u64 ctx_out;
+ __u32 cpu_plus; /* run this program on cpu
+ * (cpu_plus - 1).
+ * If cpu_plus == 0, run on
+ * current cpu.
+ */
} test;
struct { /* anonymous struct used by BPF_*_GET_*_ID */
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index ec68d3a23a2b7..4664531ff92ea 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2975,7 +2975,7 @@ static int bpf_prog_query(const union bpf_attr *attr,
}
}
-#define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
+#define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu_plus
static int bpf_prog_test_run(const union bpf_attr *attr,
union bpf_attr __user *uattr)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index b2a5380eb1871..4553aebf53862 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1675,6 +1675,7 @@ const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
};
const struct bpf_prog_ops raw_tracepoint_prog_ops = {
+ .test_run = bpf_prog_test_run_raw_tp,
};
const struct bpf_verifier_ops tracing_verifier_ops = {
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 99eb8c6c0fbcc..b32e22f0ee16f 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -11,6 +11,7 @@
#include <net/sock.h>
#include <net/tcp.h>
#include <linux/error-injection.h>
+#include <linux/smp.h>
#define CREATE_TRACE_POINTS
#include <trace/events/bpf_test_run.h>
@@ -204,6 +205,9 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
int b = 2, err = -EFAULT;
u32 retval = 0;
+ if (kattr->test.cpu_plus)
+ return -EINVAL;
+
switch (prog->expected_attach_type) {
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
@@ -236,6 +240,84 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
return err;
}
+struct bpf_raw_tp_test_run_info {
+ struct bpf_prog *prog;
+ void *ctx;
+ u32 retval;
+};
+
+static void
+__bpf_prog_test_run_raw_tp(void *data)
+{
+ struct bpf_raw_tp_test_run_info *info = data;
+
+ rcu_read_lock();
+ migrate_disable();
+ info->retval = BPF_PROG_RUN(info->prog, info->ctx);
+ migrate_enable();
+ rcu_read_unlock();
+}
+
+int bpf_prog_test_run_raw_tp(struct bpf_prog *prog,
+ const union bpf_attr *kattr,
+ union bpf_attr __user *uattr)
+{
+ void __user *ctx_in = u64_to_user_ptr(kattr->test.ctx_in);
+ __u32 ctx_size_in = kattr->test.ctx_size_in;
+ struct bpf_raw_tp_test_run_info info;
+ int cpu, err = 0;
+
+ /* doesn't support data_in/out, ctx_out, duration, or repeat */
+ if (kattr->test.data_in || kattr->test.data_out ||
+ kattr->test.ctx_out || kattr->test.duration ||
+ kattr->test.repeat)
+ return -EINVAL;
+
+ if (ctx_size_in < prog->aux->max_ctx_offset)
+ return -EINVAL;
+
+ if (ctx_size_in) {
+ info.ctx = kzalloc(ctx_size_in, GFP_USER);
+ if (!info.ctx)
+ return -ENOMEM;
+ if (copy_from_user(info.ctx, ctx_in, ctx_size_in)) {
+ err = -EFAULT;
+ goto out;
+ }
+ } else {
+ info.ctx = NULL;
+ }
+
+ info.prog = prog;
+ cpu = kattr->test.cpu_plus - 1;
+
+ if (!kattr->test.cpu_plus || cpu == smp_processor_id()) {
+ __bpf_prog_test_run_raw_tp(&info);
+ } else {
+ /* smp_call_function_single() also checks cpu_online()
+ * after csd_lock(). However, since cpu_plus is from user
+ * space, let's do an extra quick check to filter out
+ * invalid value before smp_call_function_single().
+ */
+ if (!cpu_online(cpu)) {
+ err = -ENXIO;
+ goto out;
+ }
+
+ err = smp_call_function_single(cpu, __bpf_prog_test_run_raw_tp,
+ &info, 1);
+ if (err)
+ goto out;
+ }
+
+ if (copy_to_user(&uattr->test.retval, &info.retval, sizeof(u32)))
+ err = -EFAULT;
+
+out:
+ kfree(info.ctx);
+ return err;
+}
+
static void *bpf_ctx_init(const union bpf_attr *kattr, u32 max_size)
{
void __user *data_in = u64_to_user_ptr(kattr->test.ctx_in);
@@ -410,6 +492,9 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
void *data;
int ret;
+ if (kattr->test.cpu_plus)
+ return -EINVAL;
+
data = bpf_test_init(kattr, size, NET_SKB_PAD + NET_IP_ALIGN,
SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
if (IS_ERR(data))
@@ -607,6 +692,9 @@ int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
if (prog->type != BPF_PROG_TYPE_FLOW_DISSECTOR)
return -EINVAL;
+ if (kattr->test.cpu_plus)
+ return -EINVAL;
+
if (size < ETH_HLEN)
return -EINVAL;
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index a22812561064a..89acf41913e70 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -566,6 +566,11 @@ union bpf_attr {
*/
__aligned_u64 ctx_in;
__aligned_u64 ctx_out;
+ __u32 cpu_plus; /* run this program on cpu
+ * (cpu_plus - 1).
+ * If cpu_plus == 0, run on
+ * current cpu.
+ */
} test;
struct { /* anonymous struct used by BPF_*_GET_*_ID */
--
2.24.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v3 bpf-next 2/3] libbpf: introduce bpf_prog_test_run_xattr_opts
2020-09-23 21:33 [PATCH v3 bpf-next 0/3] enable BPF_PROG_TEST_RUN for raw_tp Song Liu
2020-09-23 21:33 ` [PATCH v3 bpf-next 1/3] bpf: enable BPF_PROG_TEST_RUN for raw_tracepoint Song Liu
@ 2020-09-23 21:33 ` Song Liu
2020-09-23 21:33 ` [PATCH v3 bpf-next 3/3] selftests/bpf: add raw_tp_test_run Song Liu
2020-09-23 21:50 ` [PATCH v3 bpf-next 0/3] enable BPF_PROG_TEST_RUN for raw_tp Song Liu
3 siblings, 0 replies; 5+ messages in thread
From: Song Liu @ 2020-09-23 21:33 UTC (permalink / raw)
To: netdev, bpf; +Cc: kernel-team, ast, daniel, john.fastabend, kpsingh, Song Liu
This API supports new field cpu_plus in bpf_attr.test.
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
---
tools/lib/bpf/bpf.c | 13 ++++++++++++-
tools/lib/bpf/bpf.h | 11 +++++++++++
tools/lib/bpf/libbpf.map | 1 +
3 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 2baa1308737c8..3228dd60fa32f 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -684,7 +684,8 @@ int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
return ret;
}
-int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
+int bpf_prog_test_run_xattr_opts(struct bpf_prog_test_run_attr *test_attr,
+ const struct bpf_prog_test_run_opts *opts)
{
union bpf_attr attr;
int ret;
@@ -693,6 +694,11 @@ int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
return -EINVAL;
memset(&attr, 0, sizeof(attr));
+ if (opts) {
+ if (!OPTS_VALID(opts, bpf_prog_test_run_opts))
+ return -EINVAL;
+ attr.test.cpu_plus = opts->cpu_plus;
+ }
attr.test.prog_fd = test_attr->prog_fd;
attr.test.data_in = ptr_to_u64(test_attr->data_in);
attr.test.data_out = ptr_to_u64(test_attr->data_out);
@@ -712,6 +718,11 @@ int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
return ret;
}
+int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
+{
+ return bpf_prog_test_run_xattr_opts(test_attr, NULL);
+}
+
static int bpf_obj_get_next_id(__u32 start_id, __u32 *next_id, int cmd)
{
union bpf_attr attr;
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 8c1ac4b42f908..61318f47c8e1b 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -251,6 +251,17 @@ struct bpf_prog_bind_opts {
LIBBPF_API int bpf_prog_bind_map(int prog_fd, int map_fd,
const struct bpf_prog_bind_opts *opts);
+
+struct bpf_prog_test_run_opts {
+ size_t sz; /* size of this struct for forward/backward compatibility */
+ __u32 cpu_plus;
+};
+#define bpf_prog_test_run_opts__last_field cpu_plus
+
+LIBBPF_API
+int bpf_prog_test_run_xattr_opts(struct bpf_prog_test_run_attr *test_attr,
+ const struct bpf_prog_test_run_opts *opts);
+
#ifdef __cplusplus
} /* extern "C" */
#endif
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 5f054dadf0829..c84a8bec57634 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -303,6 +303,7 @@ LIBBPF_0.1.0 {
LIBBPF_0.2.0 {
global:
bpf_prog_bind_map;
+ bpf_prog_test_run_xattr_opts;
bpf_program__section_name;
perf_buffer__buffer_cnt;
perf_buffer__buffer_fd;
--
2.24.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v3 bpf-next 3/3] selftests/bpf: add raw_tp_test_run
2020-09-23 21:33 [PATCH v3 bpf-next 0/3] enable BPF_PROG_TEST_RUN for raw_tp Song Liu
2020-09-23 21:33 ` [PATCH v3 bpf-next 1/3] bpf: enable BPF_PROG_TEST_RUN for raw_tracepoint Song Liu
2020-09-23 21:33 ` [PATCH v3 bpf-next 2/3] libbpf: introduce bpf_prog_test_run_xattr_opts Song Liu
@ 2020-09-23 21:33 ` Song Liu
2020-09-23 21:50 ` [PATCH v3 bpf-next 0/3] enable BPF_PROG_TEST_RUN for raw_tp Song Liu
3 siblings, 0 replies; 5+ messages in thread
From: Song Liu @ 2020-09-23 21:33 UTC (permalink / raw)
To: netdev, bpf; +Cc: kernel-team, ast, daniel, john.fastabend, kpsingh, Song Liu
This test runs test_run for raw_tracepoint program. The test covers ctx
input, retval output, and proper handling of cpu_plus field.
Signed-off-by: Song Liu <songliubraving@fb.com>
---
.../bpf/prog_tests/raw_tp_test_run.c | 75 +++++++++++++++++++
.../bpf/progs/test_raw_tp_test_run.c | 25 +++++++
2 files changed, 100 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/raw_tp_test_run.c
create mode 100644 tools/testing/selftests/bpf/progs/test_raw_tp_test_run.c
diff --git a/tools/testing/selftests/bpf/prog_tests/raw_tp_test_run.c b/tools/testing/selftests/bpf/prog_tests/raw_tp_test_run.c
new file mode 100644
index 0000000000000..492cd8a8c0e00
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/raw_tp_test_run.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2019 Facebook */
+#include <test_progs.h>
+#include "bpf/libbpf_internal.h"
+#include "test_raw_tp_test_run.skel.h"
+
+static int duration;
+
+void test_raw_tp_test_run(void)
+{
+ struct bpf_prog_test_run_attr test_attr = {};
+ __u64 args[2] = {0x1234ULL, 0x5678ULL};
+ int comm_fd = -1, err, nr_online, i;
+ int expected_retval = 0x1234 + 0x5678;
+ struct test_raw_tp_test_run *skel;
+ char buf[] = "new_name";
+ bool *online = NULL;
+
+ err = parse_cpu_mask_file("/sys/devices/system/cpu/online", &online,
+ &nr_online);
+ if (CHECK(err, "parse_cpu_mask_file", "err %d\n", err))
+ return;
+
+ skel = test_raw_tp_test_run__open_and_load();
+ if (CHECK(!skel, "skel_open", "failed to open skeleton\n")) {
+ free(online);
+ return;
+ }
+ err = test_raw_tp_test_run__attach(skel);
+ if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))
+ goto cleanup;
+
+ comm_fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
+ if (CHECK(comm_fd < 0, "open /proc/self/comm", "err %d\n", errno))
+ goto cleanup;
+
+ err = write(comm_fd, buf, sizeof(buf));
+ CHECK(err < 0, "task rename", "err %d", errno);
+
+ CHECK(skel->bss->count == 0, "check_count", "didn't increase\n");
+ CHECK(skel->data->on_cpu != 0xffffffff, "check_on_cpu", "got wrong value\n");
+
+ test_attr.prog_fd = bpf_program__fd(skel->progs.rename);
+ test_attr.ctx_in = args;
+ test_attr.ctx_size_in = sizeof(__u64);
+
+ err = bpf_prog_test_run_xattr(&test_attr);
+ CHECK(err == 0, "test_run", "should fail for too small ctx\n");
+
+ test_attr.ctx_size_in = sizeof(args);
+ err = bpf_prog_test_run_xattr(&test_attr);
+ CHECK(err < 0, "test_run", "err %d\n", errno);
+ CHECK(test_attr.retval != expected_retval, "check_retval",
+ "expect 0x%x, got 0x%x\n", expected_retval, test_attr.retval);
+
+ for (i = 0; i < nr_online; i++)
+ if (online[i]) {
+ DECLARE_LIBBPF_OPTS(bpf_prog_test_run_opts, opts,
+ .cpu_plus = i + 1,
+ );
+
+ test_attr.retval = 0;
+ err = bpf_prog_test_run_xattr_opts(&test_attr, &opts);
+ CHECK(err < 0, "test_run_with_opts", "err %d\n", errno);
+ CHECK(skel->data->on_cpu != i, "check_on_cpu",
+ "got wrong value\n");
+ CHECK(test_attr.retval != expected_retval,
+ "check_retval", "expect 0x%x, got 0x%x\n",
+ expected_retval, test_attr.retval);
+ }
+cleanup:
+ close(comm_fd);
+ test_raw_tp_test_run__destroy(skel);
+ free(online);
+}
diff --git a/tools/testing/selftests/bpf/progs/test_raw_tp_test_run.c b/tools/testing/selftests/bpf/progs/test_raw_tp_test_run.c
new file mode 100644
index 0000000000000..6b356e003d16c
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_raw_tp_test_run.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+#include <bpf/bpf_tracing.h>
+
+__u32 count = 0;
+__u32 on_cpu = 0xffffffff;
+
+SEC("raw_tp/task_rename")
+int BPF_PROG(rename, struct task_struct *task, char *comm)
+{
+
+ count++;
+ if ((__u64) task == 0x1234ULL && (__u64) comm == 0x5678ULL) {
+ on_cpu = bpf_get_smp_processor_id();
+ return (int)task + (int)comm;
+ }
+
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
--
2.24.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH v3 bpf-next 0/3] enable BPF_PROG_TEST_RUN for raw_tp
2020-09-23 21:33 [PATCH v3 bpf-next 0/3] enable BPF_PROG_TEST_RUN for raw_tp Song Liu
` (2 preceding siblings ...)
2020-09-23 21:33 ` [PATCH v3 bpf-next 3/3] selftests/bpf: add raw_tp_test_run Song Liu
@ 2020-09-23 21:50 ` Song Liu
3 siblings, 0 replies; 5+ messages in thread
From: Song Liu @ 2020-09-23 21:50 UTC (permalink / raw)
To: Networking, bpf; +Cc: Kernel Team, ast, daniel, john.fastabend, kpsingh
> On Sep 23, 2020, at 2:33 PM, Song Liu <songliubraving@fb.com> wrote:
>
> This set enables BPF_PROG_TEST_RUN for raw_tracepoint type programs. This
> set also enables running the raw_tp program on a specific CPU. This feature
> can be used by user space to trigger programs that access percpu resources,
> e.g. perf_event, percpu variables.
>
> Changes v2 => v3:
> 1. Fix memory leak in the selftest. (Andrii)
> 2. Use __u64 instead of unsigned long long. (Andrii)
>
> Changes v1 => v2:
> 1. More checks for retval in the selftest. (John)
> 2. Remove unnecessary goto in bpf_prog_test_run_raw_tp. (John)
I somehow missed Andrii's other comments and sent v3 too fast.
Please ignore this version.
^ permalink raw reply [flat|nested] 5+ messages in thread