| Message ID | 20230623141546.3751-4-laoar.shao@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | bpf: Support ->fill_link_info for kprobe_multi and perf_event links | expand |
2023-06-23 14:15 UTC+0000 ~ Yafang Shao <laoar.shao@gmail.com> > Show the already expose kprobe_multi link info in bpftool. The result as > follows, > > $ tools/bpf/bpftool/bpftool link show > 4: kprobe_multi prog 22 > kprobe.multi func_cnt 7 > addr func [module] > ffffffffbbc44f20 schedule_timeout_interruptible > ffffffffbbc44f60 schedule_timeout_killable > ffffffffbbc44fa0 schedule_timeout_uninterruptible > ffffffffbbc44fe0 schedule_timeout_idle > ffffffffc08028d0 xfs_trans_get_efd [xfs] > ffffffffc080fa10 xfs_trans_get_buf_map [xfs] > ffffffffc0813320 xfs_trans_get_dqtrx [xfs] > pids kprobe_multi(1434978) > 5: kprobe_multi prog 22 > kretprobe.multi func_cnt 7 > addr func [module] > ffffffffbbc44f20 schedule_timeout_interruptible > ffffffffbbc44f60 schedule_timeout_killable > ffffffffbbc44fa0 schedule_timeout_uninterruptible > ffffffffbbc44fe0 schedule_timeout_idle > ffffffffc08028d0 xfs_trans_get_efd [xfs] > ffffffffc080fa10 xfs_trans_get_buf_map [xfs] > ffffffffc0813320 xfs_trans_get_dqtrx [xfs] > pids kprobe_multi(1434978) > > $ tools/bpf/bpftool/bpftool link show -j > [{"id":4,"type":"kprobe_multi","prog_id":22,"retprobe":false,"func_cnt":7,"funcs":[{"addr":18446744072564789024,"func":"schedule_timeout_interruptible","module":""},{"addr":18446744072564789088,"func":"schedule_timeout_killable","module":""},{"addr":18446744072564789152,"func":"schedule_timeout_uninterruptible","module":""},{"addr":18446744072564789216,"func":"schedule_timeout_idle","module":""},{"addr":18446744072644208848,"func":"xfs_trans_get_efd","module":"xfs"},{"addr":18446744072644262416,"func":"xfs_trans_get_buf_map","module":"xfs"},{"addr":18446744072644277024,"func":"xfs_trans_get_dqtrx","module":"xfs"}],"pids":[{"pid":1434978,"comm":"kprobe_multi"}]},{"id":5,"type":"kprobe_multi","prog_id":22,"retprobe":true,"func_cnt":7,"funcs":[{"addr":18446744072564789024,"func":"schedule_timeout_interruptible","module":""},{"addr":18446744072564789088,"func":"schedule_timeout_killable","module":""},{"addr":18446744072564789152,"func":"schedule_timeout_uninterruptible","module":""},{"addr":18446744072564789216,"func":"schedule_timeout_idle","module":""},{"addr":18446744072644208848,"func":"xfs_trans_get_efd","module":"xfs"},{"addr":18446744072644262416,"func":"xfs_trans_get_buf_map","module":"xfs"},{"addr":18446744072644277024,"func":"xfs_trans_get_dqtrx","module":"xfs"}],"pids":[{"pid":1434978,"comm":"kprobe_multi"}]}] > > When kptr_restrict is 2, the result is, > > $ tools/bpf/bpftool/bpftool link show > 4: kprobe_multi prog 22 > kprobe.multi func_cnt 7 > 5: kprobe_multi prog 22 > kretprobe.multi func_cnt 7 > > Signed-off-by: Yafang Shao <laoar.shao@gmail.com> > --- > tools/bpf/bpftool/link.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 108 insertions(+), 1 deletion(-) > > diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c > index 2d78607..8461e6d 100644 > --- a/tools/bpf/bpftool/link.c > +++ b/tools/bpf/bpftool/link.c > @@ -14,8 +14,10 @@ > > #include "json_writer.h" > #include "main.h" > +#include "xlated_dumper.h" > > static struct hashmap *link_table; > +static struct dump_data dd = {}; > > static int link_parse_fd(int *argc, char ***argv) > { > @@ -166,6 +168,45 @@ static int get_prog_info(int prog_id, struct bpf_prog_info *info) > return err; > } > > +static int cmp_u64(const void *A, const void *B) > +{ > + const __u64 *a = A, *b = B; > + > + return *a - *b; > +} > + > +static void > +show_kprobe_multi_json(struct bpf_link_info *info, json_writer_t *wtr) > +{ > + __u32 i, j = 0; > + __u64 *addrs; > + > + jsonw_bool_field(json_wtr, "retprobe", > + info->kprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN); > + jsonw_uint_field(json_wtr, "func_cnt", info->kprobe_multi.count); > + jsonw_name(json_wtr, "funcs"); > + jsonw_start_array(json_wtr); > + addrs = (__u64 *)u64_to_ptr(info->kprobe_multi.addrs); > + qsort((void *)addrs, info->kprobe_multi.count, sizeof(__u64), cmp_u64); > + > + /* Load it once for all. */ > + if (!dd.sym_count) > + kernel_syms_load(&dd); > + for (i = 0; i < dd.sym_count; i++) { > + if (dd.sym_mapping[i].address != addrs[j]) > + continue; > + jsonw_start_object(json_wtr); > + jsonw_uint_field(json_wtr, "addr", dd.sym_mapping[i].address); > + jsonw_string_field(json_wtr, "func", dd.sym_mapping[i].name); > + /* Print none if it is vmlinux */ > + jsonw_string_field(json_wtr, "module", dd.sym_mapping[i].module); We could maybe print null ("jsonw_null(json_wtr);") instead of an empty string here when we have no module name. Although I'm not sure it matters too much. Let's see whether the series needs another respin. Anyway: Reviewed-by: Quentin Monnet <quentin@isovalent.com>
On Sat, Jun 24, 2023 at 12:49 AM Quentin Monnet <quentin@isovalent.com> wrote: > > 2023-06-23 14:15 UTC+0000 ~ Yafang Shao <laoar.shao@gmail.com> > > Show the already expose kprobe_multi link info in bpftool. The result as > > follows, > > > > $ tools/bpf/bpftool/bpftool link show > > 4: kprobe_multi prog 22 > > kprobe.multi func_cnt 7 > > addr func [module] > > ffffffffbbc44f20 schedule_timeout_interruptible > > ffffffffbbc44f60 schedule_timeout_killable > > ffffffffbbc44fa0 schedule_timeout_uninterruptible > > ffffffffbbc44fe0 schedule_timeout_idle > > ffffffffc08028d0 xfs_trans_get_efd [xfs] > > ffffffffc080fa10 xfs_trans_get_buf_map [xfs] > > ffffffffc0813320 xfs_trans_get_dqtrx [xfs] > > pids kprobe_multi(1434978) > > 5: kprobe_multi prog 22 > > kretprobe.multi func_cnt 7 > > addr func [module] > > ffffffffbbc44f20 schedule_timeout_interruptible > > ffffffffbbc44f60 schedule_timeout_killable > > ffffffffbbc44fa0 schedule_timeout_uninterruptible > > ffffffffbbc44fe0 schedule_timeout_idle > > ffffffffc08028d0 xfs_trans_get_efd [xfs] > > ffffffffc080fa10 xfs_trans_get_buf_map [xfs] > > ffffffffc0813320 xfs_trans_get_dqtrx [xfs] > > pids kprobe_multi(1434978) > > > > $ tools/bpf/bpftool/bpftool link show -j > > [{"id":4,"type":"kprobe_multi","prog_id":22,"retprobe":false,"func_cnt":7,"funcs":[{"addr":18446744072564789024,"func":"schedule_timeout_interruptible","module":""},{"addr":18446744072564789088,"func":"schedule_timeout_killable","module":""},{"addr":18446744072564789152,"func":"schedule_timeout_uninterruptible","module":""},{"addr":18446744072564789216,"func":"schedule_timeout_idle","module":""},{"addr":18446744072644208848,"func":"xfs_trans_get_efd","module":"xfs"},{"addr":18446744072644262416,"func":"xfs_trans_get_buf_map","module":"xfs"},{"addr":18446744072644277024,"func":"xfs_trans_get_dqtrx","module":"xfs"}],"pids":[{"pid":1434978,"comm":"kprobe_multi"}]},{"id":5,"type":"kprobe_multi","prog_id":22,"retprobe":true,"func_cnt":7,"funcs":[{"addr":18446744072564789024,"func":"schedule_timeout_interruptible","module":""},{"addr":18446744072564789088,"func":"schedule_timeout_killable","module":""},{"addr":18446744072564789152,"func":"schedule_timeout_uninterruptible","module":""},{"addr":18446744072564789216,"func":"schedule_timeout_idle","module":""},{"addr":18446744072644208848,"func":"xfs_trans_get_efd","module":"xfs"},{"addr":18446744072644262416,"func":"xfs_trans_get_buf_map","module":"xfs"},{"addr":18446744072644277024,"func":"xfs_trans_get_dqtrx","module":"xfs"}],"pids":[{"pid":1434978,"comm":"kprobe_multi"}]}] > > > > When kptr_restrict is 2, the result is, > > > > $ tools/bpf/bpftool/bpftool link show > > 4: kprobe_multi prog 22 > > kprobe.multi func_cnt 7 > > 5: kprobe_multi prog 22 > > kretprobe.multi func_cnt 7 > > > > Signed-off-by: Yafang Shao <laoar.shao@gmail.com> > > --- > > tools/bpf/bpftool/link.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++- > > 1 file changed, 108 insertions(+), 1 deletion(-) > > > > diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c > > index 2d78607..8461e6d 100644 > > --- a/tools/bpf/bpftool/link.c > > +++ b/tools/bpf/bpftool/link.c > > @@ -14,8 +14,10 @@ > > > > #include "json_writer.h" > > #include "main.h" > > +#include "xlated_dumper.h" > > > > static struct hashmap *link_table; > > +static struct dump_data dd = {}; > > > > static int link_parse_fd(int *argc, char ***argv) > > { > > @@ -166,6 +168,45 @@ static int get_prog_info(int prog_id, struct bpf_prog_info *info) > > return err; > > } > > > > +static int cmp_u64(const void *A, const void *B) > > +{ > > + const __u64 *a = A, *b = B; > > + > > + return *a - *b; > > +} > > + > > +static void > > +show_kprobe_multi_json(struct bpf_link_info *info, json_writer_t *wtr) > > +{ > > + __u32 i, j = 0; > > + __u64 *addrs; > > + > > + jsonw_bool_field(json_wtr, "retprobe", > > + info->kprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN); > > + jsonw_uint_field(json_wtr, "func_cnt", info->kprobe_multi.count); > > + jsonw_name(json_wtr, "funcs"); > > + jsonw_start_array(json_wtr); > > + addrs = (__u64 *)u64_to_ptr(info->kprobe_multi.addrs); > > + qsort((void *)addrs, info->kprobe_multi.count, sizeof(__u64), cmp_u64); > > + > > + /* Load it once for all. */ > > + if (!dd.sym_count) > > + kernel_syms_load(&dd); > > + for (i = 0; i < dd.sym_count; i++) { > > + if (dd.sym_mapping[i].address != addrs[j]) > > + continue; > > + jsonw_start_object(json_wtr); > > + jsonw_uint_field(json_wtr, "addr", dd.sym_mapping[i].address); > > + jsonw_string_field(json_wtr, "func", dd.sym_mapping[i].name); > > + /* Print none if it is vmlinux */ > > + jsonw_string_field(json_wtr, "module", dd.sym_mapping[i].module); > > We could maybe print null ("jsonw_null(json_wtr);") instead of an empty > string here when we have no module name. Although I'm not sure it > matters too much. Let's see whether the series needs another respin. Will change it. Thanks for your review. > > Anyway: > > Reviewed-by: Quentin Monnet <quentin@isovalent.com>
diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c index 2d78607..8461e6d 100644 --- a/tools/bpf/bpftool/link.c +++ b/tools/bpf/bpftool/link.c @@ -14,8 +14,10 @@ #include "json_writer.h" #include "main.h" +#include "xlated_dumper.h" static struct hashmap *link_table; +static struct dump_data dd = {}; static int link_parse_fd(int *argc, char ***argv) { @@ -166,6 +168,45 @@ static int get_prog_info(int prog_id, struct bpf_prog_info *info) return err; } +static int cmp_u64(const void *A, const void *B) +{ + const __u64 *a = A, *b = B; + + return *a - *b; +} + +static void +show_kprobe_multi_json(struct bpf_link_info *info, json_writer_t *wtr) +{ + __u32 i, j = 0; + __u64 *addrs; + + jsonw_bool_field(json_wtr, "retprobe", + info->kprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN); + jsonw_uint_field(json_wtr, "func_cnt", info->kprobe_multi.count); + jsonw_name(json_wtr, "funcs"); + jsonw_start_array(json_wtr); + addrs = (__u64 *)u64_to_ptr(info->kprobe_multi.addrs); + qsort((void *)addrs, info->kprobe_multi.count, sizeof(__u64), cmp_u64); + + /* Load it once for all. */ + if (!dd.sym_count) + kernel_syms_load(&dd); + for (i = 0; i < dd.sym_count; i++) { + if (dd.sym_mapping[i].address != addrs[j]) + continue; + jsonw_start_object(json_wtr); + jsonw_uint_field(json_wtr, "addr", dd.sym_mapping[i].address); + jsonw_string_field(json_wtr, "func", dd.sym_mapping[i].name); + /* Print none if it is vmlinux */ + jsonw_string_field(json_wtr, "module", dd.sym_mapping[i].module); + jsonw_end_object(json_wtr); + if (j++ == info->kprobe_multi.count) + break; + } + jsonw_end_array(json_wtr); +} + static int show_link_close_json(int fd, struct bpf_link_info *info) { struct bpf_prog_info prog_info; @@ -218,6 +259,9 @@ static int show_link_close_json(int fd, struct bpf_link_info *info) jsonw_uint_field(json_wtr, "map_id", info->struct_ops.map_id); break; + case BPF_LINK_TYPE_KPROBE_MULTI: + show_kprobe_multi_json(info, json_wtr); + break; default: break; } @@ -351,6 +395,44 @@ void netfilter_dump_plain(const struct bpf_link_info *info) printf(" flags 0x%x", info->netfilter.flags); } +static void show_kprobe_multi_plain(struct bpf_link_info *info) +{ + __u32 i, j = 0; + __u64 *addrs; + + if (!info->kprobe_multi.count) + return; + + if (info->kprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN) + printf("\n\tkretprobe.multi "); + else + printf("\n\tkprobe.multi "); + printf("func_cnt %u ", info->kprobe_multi.count); + addrs = (__u64 *)u64_to_ptr(info->kprobe_multi.addrs); + qsort((void *)addrs, info->kprobe_multi.count, sizeof(__u64), cmp_u64); + + /* Load it once for all. */ + if (!dd.sym_count) + kernel_syms_load(&dd); + if (!dd.sym_count) + return; + + printf("\n\t%-16s %s", "addr", "func [module]"); + for (i = 0; i < dd.sym_count; i++) { + if (dd.sym_mapping[i].address != addrs[j]) + continue; + printf("\n\t%016lx %s", + dd.sym_mapping[i].address, dd.sym_mapping[i].name); + if (dd.sym_mapping[i].module[0] != '\0') + printf(" [%s] ", dd.sym_mapping[i].module); + else + printf(" "); + + if (j++ == info->kprobe_multi.count) + break; + } +} + static int show_link_close_plain(int fd, struct bpf_link_info *info) { struct bpf_prog_info prog_info; @@ -396,6 +478,9 @@ static int show_link_close_plain(int fd, struct bpf_link_info *info) case BPF_LINK_TYPE_NETFILTER: netfilter_dump_plain(info); break; + case BPF_LINK_TYPE_KPROBE_MULTI: + show_kprobe_multi_plain(info); + break; default: break; } @@ -417,7 +502,9 @@ static int do_show_link(int fd) { struct bpf_link_info info; __u32 len = sizeof(info); + __u64 *addrs = NULL; char buf[256]; + int count; int err; memset(&info, 0, sizeof(info)); @@ -441,12 +528,28 @@ static int do_show_link(int fd) info.iter.target_name_len = sizeof(buf); goto again; } + if (info.type == BPF_LINK_TYPE_KPROBE_MULTI && + !info.kprobe_multi.addrs) { + count = info.kprobe_multi.count; + if (count) { + addrs = calloc(count, sizeof(__u64)); + if (!addrs) { + p_err("mem alloc failed"); + close(fd); + return -1; + } + info.kprobe_multi.addrs = (unsigned long)addrs; + goto again; + } + } if (json_output) show_link_close_json(fd, &info); else show_link_close_plain(fd, &info); + if (addrs) + free(addrs); close(fd); return 0; } @@ -471,7 +574,8 @@ static int do_show(int argc, char **argv) fd = link_parse_fd(&argc, &argv); if (fd < 0) return fd; - return do_show_link(fd); + do_show_link(fd); + goto out; } if (argc) @@ -510,6 +614,9 @@ static int do_show(int argc, char **argv) if (show_pinned) delete_pinned_obj_table(link_table); +out: + if (dd.sym_count) + kernel_syms_destroy(&dd); return errno == ENOENT ? 0 : -1; }
Show the already expose kprobe_multi link info in bpftool. The result as follows, $ tools/bpf/bpftool/bpftool link show 4: kprobe_multi prog 22 kprobe.multi func_cnt 7 addr func [module] ffffffffbbc44f20 schedule_timeout_interruptible ffffffffbbc44f60 schedule_timeout_killable ffffffffbbc44fa0 schedule_timeout_uninterruptible ffffffffbbc44fe0 schedule_timeout_idle ffffffffc08028d0 xfs_trans_get_efd [xfs] ffffffffc080fa10 xfs_trans_get_buf_map [xfs] ffffffffc0813320 xfs_trans_get_dqtrx [xfs] pids kprobe_multi(1434978) 5: kprobe_multi prog 22 kretprobe.multi func_cnt 7 addr func [module] ffffffffbbc44f20 schedule_timeout_interruptible ffffffffbbc44f60 schedule_timeout_killable ffffffffbbc44fa0 schedule_timeout_uninterruptible ffffffffbbc44fe0 schedule_timeout_idle ffffffffc08028d0 xfs_trans_get_efd [xfs] ffffffffc080fa10 xfs_trans_get_buf_map [xfs] ffffffffc0813320 xfs_trans_get_dqtrx [xfs] pids kprobe_multi(1434978) $ tools/bpf/bpftool/bpftool link show -j [{"id":4,"type":"kprobe_multi","prog_id":22,"retprobe":false,"func_cnt":7,"funcs":[{"addr":18446744072564789024,"func":"schedule_timeout_interruptible","module":""},{"addr":18446744072564789088,"func":"schedule_timeout_killable","module":""},{"addr":18446744072564789152,"func":"schedule_timeout_uninterruptible","module":""},{"addr":18446744072564789216,"func":"schedule_timeout_idle","module":""},{"addr":18446744072644208848,"func":"xfs_trans_get_efd","module":"xfs"},{"addr":18446744072644262416,"func":"xfs_trans_get_buf_map","module":"xfs"},{"addr":18446744072644277024,"func":"xfs_trans_get_dqtrx","module":"xfs"}],"pids":[{"pid":1434978,"comm":"kprobe_multi"}]},{"id":5,"type":"kprobe_multi","prog_id":22,"retprobe":true,"func_cnt":7,"funcs":[{"addr":18446744072564789024,"func":"schedule_timeout_interruptible","module":""},{"addr":18446744072564789088,"func":"schedule_timeout_killable","module":""},{"addr":18446744072564789152,"func":"schedule_timeout_uninterruptible","module":""},{"addr":18446744072564789216,"func":"schedule_timeout_idle","module":""},{"addr":18446744072644208848,"func":"xfs_trans_get_efd","module":"xfs"},{"addr":18446744072644262416,"func":"xfs_trans_get_buf_map","module":"xfs"},{"addr":18446744072644277024,"func":"xfs_trans_get_dqtrx","module":"xfs"}],"pids":[{"pid":1434978,"comm":"kprobe_multi"}]}] When kptr_restrict is 2, the result is, $ tools/bpf/bpftool/bpftool link show 4: kprobe_multi prog 22 kprobe.multi func_cnt 7 5: kprobe_multi prog 22 kretprobe.multi func_cnt 7 Signed-off-by: Yafang Shao <laoar.shao@gmail.com> --- tools/bpf/bpftool/link.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 108 insertions(+), 1 deletion(-)