@@ -346,7 +346,7 @@ to special needs.
HEADER_BPF_PROG_INFO = 25,
-struct bpf_prog_info_linear, which contains detailed information about
+struct perf_bpil, which contains detailed information about
a BPF program, including type, id, tag, jited/xlated instructions, etc.
HEADER_BPF_BTF = 26,
@@ -201,6 +201,7 @@ endif
perf-y += perf-hooks.o
perf-$(CONFIG_LIBBPF) += bpf-event.o
+perf-$(CONFIG_LIBBPF) += bpf-utils.o
perf-$(CONFIG_CXX) += c++/
@@ -28,6 +28,7 @@
#include "evsel.h"
#include "evlist.h"
#include "bpf-event.h"
+#include "bpf-utils.h"
#include "block-range.h"
#include "string2.h"
#include "util/event.h"
@@ -1700,12 +1701,12 @@ static int symbol__disassemble_bpf(struct symbol *sym,
{
struct annotation *notes = symbol__annotation(sym);
struct annotation_options *opts = args->options;
- struct bpf_prog_info_linear *info_linear;
struct bpf_prog_linfo *prog_linfo = NULL;
struct bpf_prog_info_node *info_node;
int len = sym->end - sym->start;
disassembler_ftype disassemble;
struct map *map = args->ms.map;
+ struct perf_bpil *info_linear;
struct disassemble_info info;
struct dso *dso = map->dso;
int pc = 0, count, sub_id;
@@ -10,6 +10,7 @@
#include <internal/lib.h>
#include <symbol/kallsyms.h>
#include "bpf-event.h"
+#include "bpf-utils.h"
#include "debug.h"
#include "dso.h"
#include "symbol.h"
@@ -32,8 +33,6 @@ struct btf * __weak btf__load_from_kernel_by_id(__u32 id)
return err ? ERR_PTR(err) : btf;
}
-#define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr))
-
static int snprintf_hex(char *buf, size_t size, unsigned char *data, size_t len)
{
int ret = 0;
@@ -48,9 +47,9 @@ static int machine__process_bpf_event_load(struct machine *machine,
union perf_event *event,
struct perf_sample *sample __maybe_unused)
{
- struct bpf_prog_info_linear *info_linear;
struct bpf_prog_info_node *info_node;
struct perf_env *env = machine->env;
+ struct perf_bpil *info_linear;
int id = event->bpf.id;
unsigned int i;
@@ -175,9 +174,9 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
{
struct perf_record_ksymbol *ksymbol_event = &event->ksymbol;
struct perf_record_bpf_event *bpf_event = &event->bpf;
- struct bpf_prog_info_linear *info_linear;
struct perf_tool *tool = session->tool;
struct bpf_prog_info_node *info_node;
+ struct perf_bpil *info_linear;
struct bpf_prog_info *info;
struct btf *btf = NULL;
struct perf_env *env;
@@ -191,15 +190,15 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
*/
env = session->data ? &session->header.env : &perf_env;
- arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
- arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
- arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
- arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
- arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS;
- arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
- arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
+ arrays = 1UL << PERF_BPIL_JITED_KSYMS;
+ arrays |= 1UL << PERF_BPIL_JITED_FUNC_LENS;
+ arrays |= 1UL << PERF_BPIL_FUNC_INFO;
+ arrays |= 1UL << PERF_BPIL_PROG_TAGS;
+ arrays |= 1UL << PERF_BPIL_JITED_INSNS;
+ arrays |= 1UL << PERF_BPIL_LINE_INFO;
+ arrays |= 1UL << PERF_BPIL_JITED_LINE_INFO;
- info_linear = bpf_program__get_prog_info_linear(fd, arrays);
+ info_linear = get_bpf_prog_info_linear(fd, arrays);
if (IS_ERR_OR_NULL(info_linear)) {
info_linear = NULL;
pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
@@ -452,8 +451,8 @@ int perf_event__synthesize_bpf_events(struct perf_session *session,
static void perf_env__add_bpf_info(struct perf_env *env, u32 id)
{
- struct bpf_prog_info_linear *info_linear;
struct bpf_prog_info_node *info_node;
+ struct perf_bpil *info_linear;
struct btf *btf = NULL;
u64 arrays;
u32 btf_id;
@@ -463,15 +462,15 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 id)
if (fd < 0)
return;
- arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
- arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
- arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
- arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
- arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS;
- arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
- arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
+ arrays = 1UL << PERF_BPIL_JITED_KSYMS;
+ arrays |= 1UL << PERF_BPIL_JITED_FUNC_LENS;
+ arrays |= 1UL << PERF_BPIL_FUNC_INFO;
+ arrays |= 1UL << PERF_BPIL_PROG_TAGS;
+ arrays |= 1UL << PERF_BPIL_JITED_INSNS;
+ arrays |= 1UL << PERF_BPIL_LINE_INFO;
+ arrays |= 1UL << PERF_BPIL_JITED_LINE_INFO;
- info_linear = bpf_program__get_prog_info_linear(fd, arrays);
+ info_linear = get_bpf_prog_info_linear(fd, arrays);
if (IS_ERR_OR_NULL(info_linear)) {
pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
goto out;
@@ -19,7 +19,7 @@ struct evlist;
struct target;
struct bpf_prog_info_node {
- struct bpf_prog_info_linear *info_linear;
+ struct perf_bpil *info_linear;
struct rb_node rb_node;
};
new file mode 100644
@@ -0,0 +1,261 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <errno.h>
+#include <stdlib.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <bpf/bpf.h>
+#include "bpf-utils.h"
+#include "debug.h"
+
+struct bpil_array_desc {
+ int array_offset; /* e.g. offset of jited_prog_insns */
+ int count_offset; /* e.g. offset of jited_prog_len */
+ int size_offset; /* > 0: offset of rec size,
+ * < 0: fix size of -size_offset
+ */
+};
+
+static struct bpil_array_desc bpil_array_desc[] = {
+ [PERF_BPIL_JITED_INSNS] = {
+ offsetof(struct bpf_prog_info, jited_prog_insns),
+ offsetof(struct bpf_prog_info, jited_prog_len),
+ -1,
+ },
+ [PERF_BPIL_XLATED_INSNS] = {
+ offsetof(struct bpf_prog_info, xlated_prog_insns),
+ offsetof(struct bpf_prog_info, xlated_prog_len),
+ -1,
+ },
+ [PERF_BPIL_MAP_IDS] = {
+ offsetof(struct bpf_prog_info, map_ids),
+ offsetof(struct bpf_prog_info, nr_map_ids),
+ -(int)sizeof(__u32),
+ },
+ [PERF_BPIL_JITED_KSYMS] = {
+ offsetof(struct bpf_prog_info, jited_ksyms),
+ offsetof(struct bpf_prog_info, nr_jited_ksyms),
+ -(int)sizeof(__u64),
+ },
+ [PERF_BPIL_JITED_FUNC_LENS] = {
+ offsetof(struct bpf_prog_info, jited_func_lens),
+ offsetof(struct bpf_prog_info, nr_jited_func_lens),
+ -(int)sizeof(__u32),
+ },
+ [PERF_BPIL_FUNC_INFO] = {
+ offsetof(struct bpf_prog_info, func_info),
+ offsetof(struct bpf_prog_info, nr_func_info),
+ offsetof(struct bpf_prog_info, func_info_rec_size),
+ },
+ [PERF_BPIL_LINE_INFO] = {
+ offsetof(struct bpf_prog_info, line_info),
+ offsetof(struct bpf_prog_info, nr_line_info),
+ offsetof(struct bpf_prog_info, line_info_rec_size),
+ },
+ [PERF_BPIL_JITED_LINE_INFO] = {
+ offsetof(struct bpf_prog_info, jited_line_info),
+ offsetof(struct bpf_prog_info, nr_jited_line_info),
+ offsetof(struct bpf_prog_info, jited_line_info_rec_size),
+ },
+ [PERF_BPIL_PROG_TAGS] = {
+ offsetof(struct bpf_prog_info, prog_tags),
+ offsetof(struct bpf_prog_info, nr_prog_tags),
+ -(int)sizeof(__u8) * BPF_TAG_SIZE,
+ },
+
+};
+
+static __u32 bpf_prog_info_read_offset_u32(struct bpf_prog_info *info,
+ int offset)
+{
+ __u32 *array = (__u32 *)info;
+
+ if (offset >= 0)
+ return array[offset / sizeof(__u32)];
+ return -(int)offset;
+}
+
+static __u64 bpf_prog_info_read_offset_u64(struct bpf_prog_info *info,
+ int offset)
+{
+ __u64 *array = (__u64 *)info;
+
+ if (offset >= 0)
+ return array[offset / sizeof(__u64)];
+ return -(int)offset;
+}
+
+static void bpf_prog_info_set_offset_u32(struct bpf_prog_info *info, int offset,
+ __u32 val)
+{
+ __u32 *array = (__u32 *)info;
+
+ if (offset >= 0)
+ array[offset / sizeof(__u32)] = val;
+}
+
+static void bpf_prog_info_set_offset_u64(struct bpf_prog_info *info, int offset,
+ __u64 val)
+{
+ __u64 *array = (__u64 *)info;
+
+ if (offset >= 0)
+ array[offset / sizeof(__u64)] = val;
+}
+
+struct perf_bpil *
+get_bpf_prog_info_linear(int fd, __u64 arrays)
+{
+ struct bpf_prog_info info = {};
+ struct perf_bpil *info_linear;
+ __u32 info_len = sizeof(info);
+ __u32 data_len = 0;
+ int i, err;
+ void *ptr;
+
+ if (arrays >> PERF_BPIL_LAST_ARRAY)
+ return ERR_PTR(-EINVAL);
+
+ /* step 1: get array dimensions */
+ err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
+ if (err) {
+ pr_debug("can't get prog info: %s", strerror(errno));
+ return ERR_PTR(-EFAULT);
+ }
+
+ /* step 2: calculate total size of all arrays */
+ for (i = PERF_BPIL_FIRST_ARRAY; i < PERF_BPIL_LAST_ARRAY; ++i) {
+ bool include_array = (arrays & (1UL << i)) > 0;
+ struct bpil_array_desc *desc;
+ __u32 count, size;
+
+ desc = bpil_array_desc + i;
+
+ /* kernel is too old to support this field */
+ if (info_len < desc->array_offset + sizeof(__u32) ||
+ info_len < desc->count_offset + sizeof(__u32) ||
+ (desc->size_offset > 0 && info_len < (__u32)desc->size_offset))
+ include_array = false;
+
+ if (!include_array) {
+ arrays &= ~(1UL << i); /* clear the bit */
+ continue;
+ }
+
+ count = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
+ size = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
+
+ data_len += count * size;
+ }
+
+ /* step 3: allocate continuous memory */
+ data_len = roundup(data_len, sizeof(__u64));
+ info_linear = malloc(sizeof(struct perf_bpil) + data_len);
+ if (!info_linear)
+ return ERR_PTR(-ENOMEM);
+
+ /* step 4: fill data to info_linear->info */
+ info_linear->arrays = arrays;
+ memset(&info_linear->info, 0, sizeof(info));
+ ptr = info_linear->data;
+
+ for (i = PERF_BPIL_FIRST_ARRAY; i < PERF_BPIL_LAST_ARRAY; ++i) {
+ struct bpil_array_desc *desc;
+ __u32 count, size;
+
+ if ((arrays & (1UL << i)) == 0)
+ continue;
+
+ desc = bpil_array_desc + i;
+ count = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
+ size = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
+ bpf_prog_info_set_offset_u32(&info_linear->info,
+ desc->count_offset, count);
+ bpf_prog_info_set_offset_u32(&info_linear->info,
+ desc->size_offset, size);
+ bpf_prog_info_set_offset_u64(&info_linear->info,
+ desc->array_offset,
+ ptr_to_u64(ptr));
+ ptr += count * size;
+ }
+
+ /* step 5: call syscall again to get required arrays */
+ err = bpf_obj_get_info_by_fd(fd, &info_linear->info, &info_len);
+ if (err) {
+ pr_debug("can't get prog info: %s", strerror(errno));
+ free(info_linear);
+ return ERR_PTR(-EFAULT);
+ }
+
+ /* step 6: verify the data */
+ for (i = PERF_BPIL_FIRST_ARRAY; i < PERF_BPIL_LAST_ARRAY; ++i) {
+ struct bpil_array_desc *desc;
+ __u32 v1, v2;
+
+ if ((arrays & (1UL << i)) == 0)
+ continue;
+
+ desc = bpil_array_desc + i;
+ v1 = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
+ v2 = bpf_prog_info_read_offset_u32(&info_linear->info,
+ desc->count_offset);
+ if (v1 != v2)
+ pr_warning("%s: mismatch in element count\n", __func__);
+
+ v1 = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
+ v2 = bpf_prog_info_read_offset_u32(&info_linear->info,
+ desc->size_offset);
+ if (v1 != v2)
+ pr_warning("%s: mismatch in rec size\n", __func__);
+ }
+
+ /* step 7: update info_len and data_len */
+ info_linear->info_len = sizeof(struct bpf_prog_info);
+ info_linear->data_len = data_len;
+
+ return info_linear;
+}
+
+void bpil_addr_to_offs(struct perf_bpil *info_linear)
+{
+ int i;
+
+ for (i = PERF_BPIL_FIRST_ARRAY; i < PERF_BPIL_LAST_ARRAY; ++i) {
+ struct bpil_array_desc *desc;
+ __u64 addr, offs;
+
+ if ((info_linear->arrays & (1UL << i)) == 0)
+ continue;
+
+ desc = bpil_array_desc + i;
+ addr = bpf_prog_info_read_offset_u64(&info_linear->info,
+ desc->array_offset);
+ offs = addr - ptr_to_u64(info_linear->data);
+ bpf_prog_info_set_offset_u64(&info_linear->info,
+ desc->array_offset, offs);
+ }
+}
+
+void bpil_offs_to_addr(struct perf_bpil *info_linear)
+{
+ int i;
+
+ for (i = PERF_BPIL_FIRST_ARRAY; i < PERF_BPIL_LAST_ARRAY; ++i) {
+ struct bpil_array_desc *desc;
+ __u64 addr, offs;
+
+ if ((info_linear->arrays & (1UL << i)) == 0)
+ continue;
+
+ desc = bpil_array_desc + i;
+ offs = bpf_prog_info_read_offset_u64(&info_linear->info,
+ desc->array_offset);
+ addr = offs + ptr_to_u64(info_linear->data);
+ bpf_prog_info_set_offset_u64(&info_linear->info,
+ desc->array_offset, addr);
+ }
+}
new file mode 100644
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+
+#ifndef __PERF_BPF_UTILS_H
+#define __PERF_BPF_UTILS_H
+
+#define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr))
+
+#ifdef HAVE_LIBBPF_SUPPORT
+
+#include <bpf/libbpf.h>
+
+/*
+ * Get bpf_prog_info in continuous memory
+ *
+ * struct bpf_prog_info has multiple arrays. The user has option to choose
+ * arrays to fetch from kernel. The following APIs provide an uniform way to
+ * fetch these data. All arrays in bpf_prog_info are stored in a single
+ * continuous memory region. This makes it easy to store the info in a
+ * file.
+ *
+ * Before writing perf_bpil to files, it is necessary to
+ * translate pointers in bpf_prog_info to offsets. Helper functions
+ * bpil_addr_to_offs() and bpil_offs_to_addr()
+ * are introduced to switch between pointers and offsets.
+ *
+ * Examples:
+ * # To fetch map_ids and prog_tags:
+ * __u64 arrays = (1UL << PERF_BPIL_MAP_IDS) |
+ * (1UL << PERF_BPIL_PROG_TAGS);
+ * struct perf_bpil *info_linear =
+ * get_bpf_prog_info_linear(fd, arrays);
+ *
+ * # To save data in file
+ * bpil_addr_to_offs(info_linear);
+ * write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
+ *
+ * # To read data from file
+ * read(f, info_linear, <proper_size>);
+ * bpil_offs_to_addr(info_linear);
+ */
+enum perf_bpil_array_types {
+ PERF_BPIL_FIRST_ARRAY = 0,
+ PERF_BPIL_JITED_INSNS = 0,
+ PERF_BPIL_XLATED_INSNS,
+ PERF_BPIL_MAP_IDS,
+ PERF_BPIL_JITED_KSYMS,
+ PERF_BPIL_JITED_FUNC_LENS,
+ PERF_BPIL_FUNC_INFO,
+ PERF_BPIL_LINE_INFO,
+ PERF_BPIL_JITED_LINE_INFO,
+ PERF_BPIL_PROG_TAGS,
+ PERF_BPIL_LAST_ARRAY,
+};
+
+struct perf_bpil {
+ /* size of struct bpf_prog_info, when the tool is compiled */
+ __u32 info_len;
+ /* total bytes allocated for data, round up to 8 bytes */
+ __u32 data_len;
+ /* which arrays are included in data */
+ __u64 arrays;
+ struct bpf_prog_info info;
+ __u8 data[];
+};
+
+struct perf_bpil *
+get_bpf_prog_info_linear(int fd, __u64 arrays);
+
+void
+bpil_addr_to_offs(struct perf_bpil *info_linear);
+
+void
+bpil_offs_to_addr(struct perf_bpil *info_linear);
+
+#endif /* HAVE_LIBBPF_SUPPORT */
+#endif /* __PERF_BPF_UTILS_H */
@@ -13,6 +13,7 @@
#include <perf/bpf_perf.h>
#include "bpf_counter.h"
+#include "bpf-utils.h"
#include "counts.h"
#include "debug.h"
#include "evsel.h"
@@ -61,14 +62,13 @@ static int bpf_program_profiler__destroy(struct evsel *evsel)
static char *bpf_target_prog_name(int tgt_fd)
{
- struct bpf_prog_info_linear *info_linear;
struct bpf_func_info *func_info;
+ struct perf_bpil *info_linear;
const struct btf_type *t;
struct btf *btf = NULL;
char *name = NULL;
- info_linear = bpf_program__get_prog_info_linear(
- tgt_fd, 1UL << BPF_PROG_INFO_FUNC_INFO);
+ info_linear = get_bpf_prog_info_linear(tgt_fd, 1UL << PERF_BPIL_FUNC_INFO);
if (IS_ERR_OR_NULL(info_linear)) {
pr_debug("failed to get info_linear for prog FD %d\n", tgt_fd);
return NULL;
@@ -14,6 +14,7 @@
#ifdef HAVE_LIBBPF_SUPPORT
#include <bpf/libbpf.h>
#include "bpf-event.h"
+#include "bpf-utils.h"
#endif
#include "compress.h"
#include "env.h"
@@ -16,6 +16,7 @@ struct perf_env perf_env;
#ifdef HAVE_LIBBPF_SUPPORT
#include "bpf-event.h"
+#include "bpf-utils.h"
#include <bpf/libbpf.h>
void perf_env__insert_bpf_prog_info(struct perf_env *env,
@@ -48,6 +48,7 @@
#include "util/util.h" // perf_exe()
#include "cputopo.h"
#include "bpf-event.h"
+#include "bpf-utils.h"
#include "clockid.h"
#include "pmu-hybrid.h"
@@ -1006,17 +1007,17 @@ static int write_bpf_prog_info(struct feat_fd *ff,
node = rb_entry(next, struct bpf_prog_info_node, rb_node);
next = rb_next(&node->rb_node);
- len = sizeof(struct bpf_prog_info_linear) +
+ len = sizeof(struct perf_bpil) +
node->info_linear->data_len;
/* before writing to file, translate address to offset */
- bpf_program__bpil_addr_to_offs(node->info_linear);
+ bpil_addr_to_offs(node->info_linear);
ret = do_write(ff, node->info_linear, len);
/*
* translate back to address even when do_write() fails,
* so that this function never changes the data.
*/
- bpf_program__bpil_offs_to_addr(node->info_linear);
+ bpil_offs_to_addr(node->info_linear);
if (ret < 0)
goto out;
}
@@ -3018,9 +3019,9 @@ static int process_dir_format(struct feat_fd *ff,
#ifdef HAVE_LIBBPF_SUPPORT
static int process_bpf_prog_info(struct feat_fd *ff, void *data __maybe_unused)
{
- struct bpf_prog_info_linear *info_linear;
struct bpf_prog_info_node *info_node;
struct perf_env *env = &ff->ph->env;
+ struct perf_bpil *info_linear;
u32 count, i;
int err = -1;
@@ -3049,7 +3050,7 @@ static int process_bpf_prog_info(struct feat_fd *ff, void *data __maybe_unused)
goto out;
}
- info_linear = malloc(sizeof(struct bpf_prog_info_linear) +
+ info_linear = malloc(sizeof(struct perf_bpil) +
data_len);
if (!info_linear)
goto out;
@@ -3071,7 +3072,7 @@ static int process_bpf_prog_info(struct feat_fd *ff, void *data __maybe_unused)
goto out;
/* after reading from file, translate offset to address */
- bpf_program__bpil_offs_to_addr(info_linear);
+ bpil_offs_to_addr(info_linear);
info_node->info_linear = info_linear;
perf_env__insert_bpf_prog_info(env, info_node);
}