diff options
| -rw-r--r-- | tools/bpf/bpftool/Makefile | 2 | ||||
| -rw-r--r-- | tools/bpf/bpftool/btf.c | 6 | ||||
| -rw-r--r-- | tools/bpf/bpftool/link.c | 7 | ||||
| -rw-r--r-- | tools/bpf/bpftool/main.c | 1 | ||||
| -rw-r--r-- | tools/bpf/bpftool/main.h | 27 | ||||
| -rw-r--r-- | tools/bpf/bpftool/map.c | 7 | ||||
| -rw-r--r-- | tools/bpf/bpftool/pids.c | 229 | ||||
| -rw-r--r-- | tools/bpf/bpftool/prog.c | 7 | ||||
| -rw-r--r-- | tools/bpf/bpftool/skeleton/pid_iter.bpf.c | 80 | ||||
| -rw-r--r-- | tools/bpf/bpftool/skeleton/pid_iter.h | 12 |
10 files changed, 378 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index bdb6e38c6c5c..06f436e8191a 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -150,6 +150,8 @@ $(OUTPUT)%.skel.h: $(OUTPUT)%.bpf.o $(BPFTOOL_BOOTSTRAP) $(OUTPUT)prog.o: $(OUTPUT)profiler.skel.h +$(OUTPUT)pids.o: $(OUTPUT)pid_iter.skel.h + endif endif diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index faac8189b285..fc9bc7a23db6 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -809,6 +809,7 @@ show_btf_plain(struct bpf_btf_info *info, int fd, printf("%s%u", n++ == 0 ? " map_ids " : ",", obj->obj_id); } + emit_obj_refs_plain(&refs_table, info->id, "\n\tpids "); printf("\n"); } @@ -841,6 +842,9 @@ show_btf_json(struct bpf_btf_info *info, int fd, jsonw_uint(json_wtr, obj->obj_id); } jsonw_end_array(json_wtr); /* map_ids */ + + emit_obj_refs_json(&refs_table, info->id, json_wtr); /* pids */ + jsonw_end_object(json_wtr); /* btf object */ } @@ -893,6 +897,7 @@ static int do_show(int argc, char **argv) close(fd); return err; } + build_obj_refs_table(&refs_table, BPF_OBJ_BTF); if (fd >= 0) { err = show_btf(fd, &btf_prog_table, &btf_map_table); @@ -939,6 +944,7 @@ static int do_show(int argc, char **argv) exit_free: delete_btf_table(&btf_prog_table); delete_btf_table(&btf_map_table); + delete_obj_refs_table(&refs_table); return err; } diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c index fca57ee8fafe..7329f3134283 100644 --- a/tools/bpf/bpftool/link.c +++ b/tools/bpf/bpftool/link.c @@ -143,6 +143,9 @@ static int show_link_close_json(int fd, struct bpf_link_info *info) } jsonw_end_array(json_wtr); } + + emit_obj_refs_json(&refs_table, info->id, json_wtr); + jsonw_end_object(json_wtr); return 0; @@ -212,6 +215,7 @@ static int show_link_close_plain(int fd, struct bpf_link_info *info) printf("\n\tpinned %s", obj->path); } } + emit_obj_refs_plain(&refs_table, info->id, "\n\tpids "); printf("\n"); @@ -257,6 +261,7 @@ static int do_show(int argc, char **argv) if (show_pinned) build_pinned_obj_table(&link_table, BPF_OBJ_LINK); + build_obj_refs_table(&refs_table, BPF_OBJ_LINK); if (argc == 2) { fd = link_parse_fd(&argc, &argv); @@ -296,6 +301,8 @@ static int do_show(int argc, char **argv) if (json_output) jsonw_end_array(json_wtr); + delete_obj_refs_table(&refs_table); + return errno == ENOENT ? 0 : -1; } diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index bf4d7487552a..4a191fcbeb82 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -31,6 +31,7 @@ bool relaxed_maps; struct pinned_obj_table prog_table; struct pinned_obj_table map_table; struct pinned_obj_table link_table; +struct obj_refs_table refs_table; static void __noreturn clean_and_exit(int i) { diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index aad7be74e8a7..ce26271e5f0c 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -127,11 +127,13 @@ static const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = { extern const char * const map_type_name[]; extern const size_t map_type_name_size; +/* keep in sync with the definition in skeleton/pid_iter.bpf.c */ enum bpf_obj_type { BPF_OBJ_UNKNOWN, BPF_OBJ_PROG, BPF_OBJ_MAP, BPF_OBJ_LINK, + BPF_OBJ_BTF, }; extern const char *bin_name; @@ -139,12 +141,14 @@ extern const char *bin_name; extern json_writer_t *json_wtr; extern bool json_output; extern bool show_pinned; +extern bool show_pids; extern bool block_mount; extern bool verifier_logs; extern bool relaxed_maps; extern struct pinned_obj_table prog_table; extern struct pinned_obj_table map_table; extern struct pinned_obj_table link_table; +extern struct obj_refs_table refs_table; void __printf(1, 2) p_err(const char *fmt, ...); void __printf(1, 2) p_info(const char *fmt, ...); @@ -168,12 +172,35 @@ struct pinned_obj { struct hlist_node hash; }; +struct obj_refs_table { + DECLARE_HASHTABLE(table, 16); +}; + +struct obj_ref { + int pid; + char comm[16]; +}; + +struct obj_refs { + struct hlist_node node; + __u32 id; + int ref_cnt; + struct obj_ref *refs; +}; + struct btf; struct bpf_line_info; int build_pinned_obj_table(struct pinned_obj_table *table, enum bpf_obj_type type); void delete_pinned_obj_table(struct pinned_obj_table *tab); +__weak int build_obj_refs_table(struct obj_refs_table *table, + enum bpf_obj_type type); +__weak void delete_obj_refs_table(struct obj_refs_table *table); +__weak void emit_obj_refs_json(struct obj_refs_table *table, __u32 id, + json_writer_t *json_wtr); +__weak void emit_obj_refs_plain(struct obj_refs_table *table, __u32 id, + const char *prefix); void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode); void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode); diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index b9eee19b094c..0a6a5d82d380 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -509,6 +509,8 @@ static int show_map_close_json(int fd, struct bpf_map_info *info) jsonw_end_array(json_wtr); } + emit_obj_refs_json(&refs_table, info->id, json_wtr); + jsonw_end_object(json_wtr); return 0; @@ -596,6 +598,8 @@ static int show_map_close_plain(int fd, struct bpf_map_info *info) if (frozen) printf("%sfrozen", info->btf_id ? " " : ""); + emit_obj_refs_plain(&refs_table, info->id, "\n\tpids "); + printf("\n"); return 0; } @@ -654,6 +658,7 @@ static int do_show(int argc, char **argv) if (show_pinned) build_pinned_obj_table(&map_table, BPF_OBJ_MAP); + build_obj_refs_table(&refs_table, BPF_OBJ_MAP); if (argc == 2) return do_show_subset(argc, argv); @@ -697,6 +702,8 @@ static int do_show(int argc, char **argv) if (json_output) jsonw_end_array(json_wtr); + delete_obj_refs_table(&refs_table); + return errno == ENOENT ? 0 : -1; } diff --git a/tools/bpf/bpftool/pids.c b/tools/bpf/bpftool/pids.c new file mode 100644 index 000000000000..3474a91743ff --- /dev/null +++ b/tools/bpf/bpftool/pids.c @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +/* Copyright (C) 2020 Facebook */ +#include <errno.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <bpf/bpf.h> + +#include "main.h" +#include "skeleton/pid_iter.h" + +#ifdef BPFTOOL_WITHOUT_SKELETONS + +int build_obj_refs_table(struct obj_refs_table *table, enum bpf_obj_type type) +{ + p_err("bpftool built without PID iterator support"); + return -ENOTSUP; +} +void delete_obj_refs_table(struct obj_refs_table *table) {} + +#else /* BPFTOOL_WITHOUT_SKELETONS */ + +#include "pid_iter.skel.h" + +static void add_ref(struct obj_refs_table *table, struct pid_iter_entry *e) +{ + struct obj_refs *refs; + struct obj_ref *ref; + void *tmp; + int i; + + hash_for_each_possible(table->table, refs, node, e->id) { + if (refs->id != e->id) + continue; + + for (i = 0; i < refs->ref_cnt; i++) { + if (refs->refs[i].pid == e->pid) + return; + } + + tmp = realloc(refs->refs, (refs->ref_cnt + 1) * sizeof(*ref)); + if (!tmp) { + p_err("failed to re-alloc memory for ID %u, PID %d, COMM %s...", + e->id, e->pid, e->comm); + return; + } + refs->refs = tmp; + ref = &refs->refs[refs->ref_cnt]; + ref->pid = e->pid; + memcpy(ref->comm, e->comm, sizeof(ref->comm)); + refs->ref_cnt++; + + return; + } + + /* new ref */ + refs = calloc(1, sizeof(*refs)); + if (!refs) { + p_err("failed to alloc memory for ID %u, PID %d, COMM %s...", + e->id, e->pid, e->comm); + return; + } + + refs->id = e->id; + refs->refs = malloc(sizeof(*refs->refs)); + if (!refs->refs) { + free(refs); + p_err("failed to alloc memory for ID %u, PID %d, COMM %s...", + e->id, e->pid, e->comm); + return; + } + ref = &refs->refs[0]; + ref->pid = e->pid; + memcpy(ref->comm, e->comm, sizeof(ref->comm)); + refs->ref_cnt = 1; + hash_add(table->table, &refs->node, e->id); +} + +static int __printf(2, 0) +libbpf_print_none(__maybe_unused enum libbpf_print_level level, + __maybe_unused const char *format, + __maybe_unused va_list args) +{ + return 0; +} + +int build_obj_refs_table(struct obj_refs_table *table, enum bpf_obj_type type) +{ + char buf[4096]; + struct pid_iter_bpf *skel; + struct pid_iter_entry *e; + int err, ret, fd = -1, i; + libbpf_print_fn_t default_print; + + hash_init(table->table); + set_max_rlimit(); + + skel = pid_iter_bpf__open(); + if (!skel) { + p_err("failed to open PID iterator skeleton"); + return -1; + } + + skel->rodata->obj_type = type; + + /* we don't want output polluted with libbpf errors if bpf_iter is not + * supported + */ + default_print = libbpf_set_print(libbpf_print_none); + err = pid_iter_bpf__load(skel); + libbpf_set_print(default_print); + if (err) { + /* too bad, kernel doesn't support BPF iterators yet */ + err = 0; + goto out; + } + err = pid_iter_bpf__attach(skel); + if (err) { + /* if we loaded above successfully, attach has to succeed */ + p_err("failed to attach PID iterator: %d", err); + goto out; + } + + fd = bpf_iter_create(bpf_link__fd(skel->links.iter)); + if (fd < 0) { + err = -errno; + p_err("failed to create PID iterator session: %d", err); + goto out; + } + + while (true) { + ret = read(fd, buf, sizeof(buf)); + if (ret < 0) { + err = -errno; + p_err("failed to read PID iterator output: %d", err); + goto out; + } + if (ret == 0) + break; + if (ret % sizeof(*e)) { + err = -EINVAL; + p_err("invalid PID iterator output format"); + goto out; + } + ret /= sizeof(*e); + + e = (void *)buf; + for (i = 0; i < ret; i++, e++) { + add_ref(table, e); + } + } + err = 0; +out: + if (fd >= 0) + close(fd); + pid_iter_bpf__destroy(skel); + return err; +} + +void delete_obj_refs_table(struct obj_refs_table *table) +{ + struct obj_refs *refs; + struct hlist_node *tmp; + unsigned int bkt; + + hash_for_each_safe(table->table, bkt, tmp, refs, node) { + hash_del(&refs->node); + free(refs->refs); + free(refs); + } +} + +void emit_obj_refs_json(struct obj_refs_table *table, __u32 id, json_writer_t *json_wtr) +{ + struct obj_refs *refs; + struct obj_ref *ref; + int i; + + if (hash_empty(table->table)) + return; + + hash_for_each_possible(table->table, refs, node, id) { + if (refs->id != id) + continue; + if (refs->ref_cnt == 0) + break; + + jsonw_name(json_wtr, "pids"); + jsonw_start_array(json_wtr); + for (i = 0; i < refs->ref_cnt; i++) { + ref = &refs->refs[i]; + jsonw_start_object(json_wtr); + jsonw_int_field(json_wtr, "pid", ref->pid); + jsonw_string_field(json_wtr, "comm", ref->comm); + jsonw_end_object(json_wtr); + } + jsonw_end_array(json_wtr); + break; + } +} + +void emit_obj_refs_plain(struct obj_refs_table *table, __u32 id, const char *prefix) +{ + struct obj_refs *refs; + struct obj_ref *ref; + int i; + + if (hash_empty(table->table)) + return; + + hash_for_each_possible(table->table, refs, node, id) { + if (refs->id != id) + continue; + if (refs->ref_cnt == 0) + break; + + printf("%s", prefix); + for (i = 0; i < refs->ref_cnt; i++) { + ref = &refs->refs[i]; + printf("%s%s(%d)", i == 0 ? "" : ", ", ref->comm, ref->pid); + } + break; + } +} + + +#endif diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 53d47610ff58..e21fa8ad2efa 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -190,6 +190,8 @@ static void print_prog_json(struct bpf_prog_info *info, int fd) jsonw_end_array(json_wtr); } + emit_obj_refs_json(&refs_table, info->id, json_wtr); + jsonw_end_object(json_wtr); } @@ -256,6 +258,8 @@ static void print_prog_plain(struct bpf_prog_info *info, int fd) if (info->btf_id) printf("\n\tbtf_id %d", info->btf_id); + emit_obj_refs_plain(&refs_table, info->id, "\n\tpids "); + printf("\n"); } @@ -321,6 +325,7 @@ static int do_show(int argc, char **argv) if (show_pinned) build_pinned_obj_table(&prog_table, BPF_OBJ_PROG); + build_obj_refs_table(&refs_table, BPF_OBJ_PROG); if (argc == 2) return do_show_subset(argc, argv); @@ -362,6 +367,8 @@ static int do_show(int argc, char **argv) if (json_output) jsonw_end_array(json_wtr); + delete_obj_refs_table(&refs_table); + return err; } diff --git a/tools/bpf/bpftool/skeleton/pid_iter.bpf.c b/tools/bpf/bpftool/skeleton/pid_iter.bpf.c new file mode 100644 index 000000000000..8468a608911e --- /dev/null +++ b/tools/bpf/bpftool/skeleton/pid_iter.bpf.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +/* Copyright (c) 2020 Facebook */ +#include <vmlinux.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_core_read.h> +#include <bpf/bpf_tracing.h> +#include "pid_iter.h" + +/* keep in sync with the definition in main.h */ +enum bpf_obj_type { + BPF_OBJ_UNKNOWN, + BPF_OBJ_PROG, + BPF_OBJ_MAP, + BPF_OBJ_LINK, + BPF_OBJ_BTF, +}; + +extern const void bpf_link_fops __ksym; +extern const void bpf_map_fops __ksym; +extern const void bpf_prog_fops __ksym; +extern const void btf_fops __ksym; + +const volatile enum bpf_obj_type obj_type = BPF_OBJ_UNKNOWN; + +static __always_inline __u32 get_obj_id(void *ent, enum bpf_obj_type type) +{ + switch (type) { + case BPF_OBJ_PROG: + return BPF_CORE_READ((struct bpf_prog *)ent, aux, id); + case BPF_OBJ_MAP: + return BPF_CORE_READ((struct bpf_map *)ent, id); + case BPF_OBJ_BTF: + return BPF_CORE_READ((struct btf *)ent, id); + case BPF_OBJ_LINK: + return BPF_CORE_READ((struct bpf_link *)ent, id); + default: + return 0; + } +} + +SEC("iter/task_file") +int iter(struct bpf_iter__task_file *ctx) +{ + struct file *file = ctx->file; + struct task_struct *task = ctx->task; + struct pid_iter_entry e; + const void *fops; + + if (!file || !task) + return 0; + + switch (obj_type) { + case BPF_OBJ_PROG: + fops = &bpf_prog_fops; + break; + case BPF_OBJ_MAP: + fops = &bpf_map_fops; + break; + case BPF_OBJ_BTF: + fops = &btf_fops; + break; + case BPF_OBJ_LINK: + fops = &bpf_link_fops; + break; + default: + return 0; + } + + if (file->f_op != fops) + return 0; + + e.pid = task->tgid; + e.id = get_obj_id(file->private_data, obj_type); + bpf_probe_read(&e.comm, sizeof(e.comm), task->group_leader->comm); + bpf_seq_write(ctx->meta->seq, &e, sizeof(e)); + + return 0; +} + +char LICENSE[] SEC("license") = "Dual BSD/GPL"; diff --git a/tools/bpf/bpftool/skeleton/pid_iter.h b/tools/bpf/bpftool/skeleton/pid_iter.h new file mode 100644 index 000000000000..5692cf257adb --- /dev/null +++ b/tools/bpf/bpftool/skeleton/pid_iter.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */ +/* Copyright (c) 2020 Facebook */ +#ifndef __PID_ITER_H +#define __PID_ITER_H + +struct pid_iter_entry { + __u32 id; + int pid; + char comm[16]; +}; + +#endif |