From 6f2b219b62a4376ca2da15c503de79d0650c8155 Mon Sep 17 00:00:00 2001 From: Hengqi Chen Date: Mon, 4 Oct 2021 00:58:44 +0800 Subject: selftests/bpf: Switch to new bpf_object__next_{map,program} APIs Replace deprecated bpf_{map,program}__next APIs with newly added bpf_object__next_{map,program} APIs, so that no compilation warnings emit. Signed-off-by: Hengqi Chen Signed-off-by: Andrii Nakryiko Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20211003165844.4054931-3-hengqi.chen@gmail.com --- tools/bpf/bpftool/prog.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools/bpf/bpftool/prog.c') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 9c3e343b7d87..a24ea7e26aa4 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -1601,7 +1601,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) goto err_close_obj; if (first_prog_only) { - prog = bpf_program__next(NULL, obj); + prog = bpf_object__next_program(obj, NULL); if (!prog) { p_err("object file doesn't contain any bpf program"); goto err_close_obj; -- cgit v1.2.3 From c66a248f1950d41502fb67624147281d9de0e868 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 7 Oct 2021 20:44:28 +0100 Subject: bpftool: Remove unused includes to It seems that the header file was never necessary to compile bpftool, and it is not part of the headers exported from libbpf. Let's remove the includes from prog.c and gen.c. Fixes: d510296d331a ("bpftool: Use syscall/loader program in "prog load" and "gen skeleton" command.") Signed-off-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211007194438.34443-3-quentin@isovalent.com --- tools/bpf/bpftool/prog.c | 1 - 1 file changed, 1 deletion(-) (limited to 'tools/bpf/bpftool/prog.c') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index a24ea7e26aa4..277d51c4c5d9 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -25,7 +25,6 @@ #include #include #include -#include #include #include "cfg.h" -- cgit v1.2.3 From e89ef634f81c9d90e1824ab183721f3b361472e6 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Fri, 22 Oct 2021 10:47:43 +0100 Subject: bpftool: Avoid leaking the JSON writer prepared for program metadata Bpftool creates a new JSON object for writing program metadata in plain text mode, regardless of metadata being present or not. Then this writer is freed if any metadata has been found and printed, but it leaks otherwise. We cannot destroy the object unconditionally, because the destructor prints an undesirable line break. Instead, make sure the writer is created only after we have found program metadata to print. Found with valgrind. Fixes: aff52e685eb3 ("bpftool: Support dumping metadata") Signed-off-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211022094743.11052-1-quentin@isovalent.com --- tools/bpf/bpftool/prog.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'tools/bpf/bpftool/prog.c') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 277d51c4c5d9..f633299b1261 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -307,18 +307,12 @@ static void show_prog_metadata(int fd, __u32 num_maps) if (printed_header) jsonw_end_object(json_wtr); } else { - json_writer_t *btf_wtr = jsonw_new(stdout); + json_writer_t *btf_wtr; struct btf_dumper d = { .btf = btf, - .jw = btf_wtr, .is_plain_text = true, }; - if (!btf_wtr) { - p_err("jsonw alloc failed"); - goto out_free; - } - for (i = 0; i < vlen; i++, vsi++) { t_var = btf__type_by_id(btf, vsi->type); name = btf__name_by_offset(btf, t_var->name_off); @@ -328,6 +322,14 @@ static void show_prog_metadata(int fd, __u32 num_maps) if (!printed_header) { printf("\tmetadata:"); + + btf_wtr = jsonw_new(stdout); + if (!btf_wtr) { + p_err("jsonw alloc failed"); + goto out_free; + } + d.jw = btf_wtr, + printed_header = true; } -- cgit v1.2.3 From 46241271d18f3ae095b7ec3d9d136d8f4e28e025 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Sat, 23 Oct 2021 21:51:51 +0100 Subject: bpftool: Do not expose and init hash maps for pinned path in main.c BPF programs, maps, and links, can all be listed with their pinned paths by bpftool, when the "-f" option is provided. To do so, bpftool builds hash maps containing all pinned paths for each kind of objects. These three hash maps are always initialised in main.c, and exposed through main.h. There appear to be no particular reason to do so: we can just as well make them static to the files that need them (prog.c, map.c, and link.c respectively), and initialise them only when we want to show objects and the "-f" switch is provided. This may prevent unnecessary memory allocations if the implementation of the hash maps was to change in the future. Signed-off-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211023205154.6710-3-quentin@isovalent.com --- tools/bpf/bpftool/prog.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'tools/bpf/bpftool/prog.c') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index f633299b1261..48c2fa4d068e 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -84,6 +84,8 @@ static const char * const attach_type_strings[] = { [__MAX_BPF_ATTACH_TYPE] = NULL, }; +static struct pinned_obj_table prog_table; + static enum bpf_attach_type parse_attach_type(const char *str) { enum bpf_attach_type type; @@ -567,8 +569,10 @@ static int do_show(int argc, char **argv) int err; int fd; - if (show_pinned) + if (show_pinned) { + hash_init(prog_table.table); build_pinned_obj_table(&prog_table, BPF_OBJ_PROG); + } build_obj_refs_table(&refs_table, BPF_OBJ_PROG); if (argc == 2) @@ -613,6 +617,9 @@ static int do_show(int argc, char **argv) delete_obj_refs_table(&refs_table); + if (show_pinned) + delete_pinned_obj_table(&prog_table); + return err; } -- cgit v1.2.3 From 8f184732b60b74a8f8ba0d9a5c248bf611b1ebba Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Sat, 23 Oct 2021 21:51:52 +0100 Subject: bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects In order to show pinned paths for BPF programs, maps, or links when listing them with the "-f" option, bpftool creates hash maps to store all relevant paths under the bpffs. So far, it would rely on the kernel implementation (from tools/include/linux/hashtable.h). We can make bpftool rely on libbpf's implementation instead. The motivation is to make bpftool less dependent of kernel headers, to ease the path to a potential out-of-tree mirror, like libbpf has. This commit is the first step of the conversion: the hash maps for pinned paths for programs, maps, and links are converted to libbpf's hashmap.{c,h}. Other hash maps used for the PIDs of process holding references to BPF objects are left unchanged for now. On the build side, this requires adding a dependency to a second header internal to libbpf, and making it a dependency for the bootstrap bpftool version as well. The rest of the changes are a rather straightforward conversion. Signed-off-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211023205154.6710-4-quentin@isovalent.com --- tools/bpf/bpftool/prog.c | 36 ++++++++++++++++++++---------------- 1 file changed, 20 insertions(+), 16 deletions(-) (limited to 'tools/bpf/bpftool/prog.c') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 48c2fa4d068e..8fce78ce6f8b 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -24,6 +24,7 @@ #include #include +#include #include #include @@ -84,7 +85,7 @@ static const char * const attach_type_strings[] = { [__MAX_BPF_ATTACH_TYPE] = NULL, }; -static struct pinned_obj_table prog_table; +static struct hashmap *prog_table; static enum bpf_attach_type parse_attach_type(const char *str) { @@ -418,15 +419,14 @@ static void print_prog_json(struct bpf_prog_info *info, int fd) if (info->btf_id) jsonw_int_field(json_wtr, "btf_id", info->btf_id); - if (!hash_empty(prog_table.table)) { - struct pinned_obj *obj; + if (!hashmap__empty(prog_table)) { + struct hashmap_entry *entry; jsonw_name(json_wtr, "pinned"); jsonw_start_array(json_wtr); - hash_for_each_possible(prog_table.table, obj, hash, info->id) { - if (obj->id == info->id) - jsonw_string(json_wtr, obj->path); - } + hashmap__for_each_key_entry(prog_table, entry, + u32_as_hash_field(info->id)) + jsonw_string(json_wtr, entry->value); jsonw_end_array(json_wtr); } @@ -490,13 +490,12 @@ static void print_prog_plain(struct bpf_prog_info *info, int fd) if (info->nr_map_ids) show_prog_maps(fd, info->nr_map_ids); - if (!hash_empty(prog_table.table)) { - struct pinned_obj *obj; + if (!hashmap__empty(prog_table)) { + struct hashmap_entry *entry; - hash_for_each_possible(prog_table.table, obj, hash, info->id) { - if (obj->id == info->id) - printf("\n\tpinned %s", obj->path); - } + hashmap__for_each_key_entry(prog_table, entry, + u32_as_hash_field(info->id)) + printf("\n\tpinned %s", (char *)entry->value); } if (info->btf_id) @@ -570,8 +569,13 @@ static int do_show(int argc, char **argv) int fd; if (show_pinned) { - hash_init(prog_table.table); - build_pinned_obj_table(&prog_table, BPF_OBJ_PROG); + prog_table = hashmap__new(hash_fn_for_key_as_id, + equal_fn_for_key_as_id, NULL); + if (!prog_table) { + p_err("failed to create hashmap for pinned paths"); + return -1; + } + build_pinned_obj_table(prog_table, BPF_OBJ_PROG); } build_obj_refs_table(&refs_table, BPF_OBJ_PROG); @@ -618,7 +622,7 @@ static int do_show(int argc, char **argv) delete_obj_refs_table(&refs_table); if (show_pinned) - delete_pinned_obj_table(&prog_table); + delete_pinned_obj_table(prog_table); return err; } -- cgit v1.2.3 From d6699f8e0f834b40db35466f704705ae757be11a Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Sat, 23 Oct 2021 21:51:54 +0100 Subject: bpftool: Switch to libbpf's hashmap for PIDs/names references In order to show PIDs and names for processes holding references to BPF programs, maps, links, or BTF objects, bpftool creates hash maps to store all relevant information. This commit is part of a set that transitions from the kernel's hash map implementation to the one coming with libbpf. The motivation is to make bpftool less dependent of kernel headers, to ease the path to a potential out-of-tree mirror, like libbpf has. This is the third and final step of the transition, in which we convert the hash maps used for storing the information about the processes holding references to BPF objects (programs, maps, links, BTF), and at last we drop the inclusion of tools/include/linux/hashtable.h. Note: Checkpatch complains about the use of __weak declarations, and the missing empty lines after the bunch of empty function declarations when compiling without the BPF skeletons (none of these were introduced in this patch). We want to keep things as they are, and the reports should be safe to ignore. Signed-off-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211023205154.6710-6-quentin@isovalent.com --- tools/bpf/bpftool/prog.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'tools/bpf/bpftool/prog.c') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 8fce78ce6f8b..515d22952602 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -430,7 +430,7 @@ 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); + emit_obj_refs_json(refs_table, info->id, json_wtr); show_prog_metadata(fd, info->nr_map_ids); @@ -501,7 +501,7 @@ 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 "); + emit_obj_refs_plain(refs_table, info->id, "\n\tpids "); printf("\n"); @@ -619,7 +619,7 @@ static int do_show(int argc, char **argv) if (json_output) jsonw_end_array(json_wtr); - delete_obj_refs_table(&refs_table); + delete_obj_refs_table(refs_table); if (show_pinned) delete_pinned_obj_table(prog_table); -- cgit v1.2.3