| Message ID | 20231208145720.411075-3-qde@naccy.de (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | David Ahern |
| Headers | show |
| Series | ss: pretty-printing BPF socket-local storage | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On 12/8/23 6:57 AM, Quentin Deslandes wrote: > @@ -1039,11 +1044,10 @@ static int buf_update(int len) > } > > /* Append content to buffer as part of the current field */ > -__attribute__((format(printf, 1, 2))) > -static void out(const char *fmt, ...) > +static void vout(const char *fmt, va_list args) > { > struct column *f = current_field; > - va_list args; > + va_list _args; > char *pos; > int len; > > @@ -1054,18 +1058,27 @@ static void out(const char *fmt, ...) > buffer.head = buf_chunk_new(); > > again: /* Append to buffer: if we have a new chunk, print again */ > + va_copy(_args, args); > > pos = buffer.cur->data + buffer.cur->len; > - va_start(args, fmt); > > /* Limit to tail room. If we hit the limit, buf_update() will tell us */ > len = vsnprintf(pos, buf_chunk_avail(buffer.tail), fmt, args); hmm... based on the changes made in this function, I am pretty sure the intention is to pass the "_args" here instead of passing the "args". Please double check. > - va_end(args); > > if (buf_update(len)) > goto again; > } > > +__attribute__((format(printf, 1, 2))) > +static void out(const char *fmt, ...) > +{ > + va_list args; > + > + va_start(args, fmt); > + vout(fmt, args); > + va_end(args); > +} > + > static int print_left_spacing(struct column *f, int stored, int printed) > { > int s; > @@ -1213,6 +1226,9 @@ static void render_calc_width(void) > */ > c->width = min(c->width, screen_width); > > + if (c == &columns[COL_SKSTOR]) > + c->width = 1; > + > if (c->width) > first = 0; > } > @@ -3392,6 +3408,8 @@ static struct bpf_map_opts { > struct bpf_sk_storage_map_info { > unsigned int id; > int fd; > + struct bpf_map_info info; > + struct btf *btf; > } maps[MAX_NR_BPF_MAP_ID_OPTS]; > bool show_all; > struct btf *kernel_btf; > @@ -3403,6 +3421,22 @@ static void bpf_map_opts_mixed_error(void) > "ss: --bpf-maps and --bpf-map-id cannot be used together\n"); > } > > +static int bpf_maps_opts_load_btf(struct bpf_map_info *info, struct btf **btf) > +{ > + if (info->btf_value_type_id) { > + *btf = btf__load_from_kernel_by_id(info->btf_id); > + if (!*btf) { > + fprintf(stderr, "ss: failed to load BTF for map ID %u\n", > + info->id); > + return -1; > + } > + } else { > + *btf = NULL; > + } > + > + return 0; > +} > + > static int bpf_map_opts_add_all(void) > { > unsigned int i; > @@ -3418,6 +3452,7 @@ static int bpf_map_opts_add_all(void) > while (1) { > struct bpf_map_info info = {}; > uint32_t len = sizeof(info); > + struct btf *btf; > > r = bpf_map_get_next_id(id, &id); > if (r) { > @@ -3462,8 +3497,18 @@ static int bpf_map_opts_add_all(void) > continue; > } > > + r = bpf_maps_opts_load_btf(&info, &btf); > + if (r) { > + fprintf(stderr, "ss: failed to get BTF data for BPF map ID: %u\n", > + id); > + close(fd); > + goto err; > + } > + > bpf_map_opts.maps[bpf_map_opts.nr_maps].id = id; > - bpf_map_opts.maps[bpf_map_opts.nr_maps++].fd = fd; > + bpf_map_opts.maps[bpf_map_opts.nr_maps].fd = fd; > + bpf_map_opts.maps[bpf_map_opts.nr_maps].info = info; > + bpf_map_opts.maps[bpf_map_opts.nr_maps++].btf = btf; The "err:" path of this function needs a btf__free(). > } > > bpf_map_opts.show_all = true; > @@ -3482,6 +3527,7 @@ static int bpf_map_opts_add_id(const char *optarg) > struct bpf_map_info info = {}; > uint32_t len = sizeof(info); > size_t optarg_len; > + struct btf *btf; > unsigned long id; > unsigned int i; > char *end; > @@ -3539,8 +3585,17 @@ static int bpf_map_opts_add_id(const char *optarg) > return -1; > } > > + r = bpf_maps_opts_load_btf(&info, &btf); > + if (r) { > + fprintf(stderr, "ss: failed to get BTF data for BPF map ID: %lu\n", > + id); close(fd); > + return -1; > + } > + > bpf_map_opts.maps[bpf_map_opts.nr_maps].id = id; > - bpf_map_opts.maps[bpf_map_opts.nr_maps++].fd = fd; > + bpf_map_opts.maps[bpf_map_opts.nr_maps].fd = fd; > + bpf_map_opts.maps[bpf_map_opts.nr_maps].info = info; > + bpf_map_opts.maps[bpf_map_opts.nr_maps++].btf = btf; > > return 0; > }
On 08/12/2023 14:57, Quentin Deslandes wrote: > ss is able to print the map ID(s) for which a given socket has BPF > socket-local storage defined (using --bpf-maps or --bpf-map-id=). However, > the actual content of the map remains hidden. > > This change aims to pretty-print the socket-local storage content following > the socket details, similar to what `bpftool map dump` would do. The exact > output format is inspired by drgn, while the BTF data processing is similar > to bpftool's. > > ss will use libbpf's btf_dump__dump_type_data() to ease pretty-printing > of binary data. This requires out_bpf_sk_storage_print_fn() as a print > callback function used by btf_dump__dump_type_data(). vout() is also > introduced, which is similar to out() but accepts a va_list as > parameter. > > COL_SKSTOR's header is replaced with an empty string, as it doesn't need to > be printed anymore; it's used as a "virtual" column to refer to the > socket-local storage dump, which will be printed under the socket information. > The column's width is fixed to 1, so it doesn't mess up ss' output. > > ss' output remains unchanged unless --bpf-maps or --bpf-map-id= is used, > in which case each socket containing BPF local storage will be followed by > the content of the storage before the next socket's info is displayed. > this is great! one small idea below, but > Signed-off-by: Quentin Deslandes <qde@naccy.de> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> > --- > misc/ss.c | 157 +++++++++++++++++++++++++++++++++++++++++++++++++----- > 1 file changed, 145 insertions(+), 12 deletions(-) > > diff --git a/misc/ss.c b/misc/ss.c > index f979b61d..6051b694 100644 > --- a/misc/ss.c > +++ b/misc/ss.c > @@ -51,8 +51,13 @@ > #include <linux/tls.h> > #include <linux/mptcp.h> > > +#ifdef HAVE_LIBBPF > +#include <linux/btf.h> > +#endif > + > #ifdef HAVE_LIBBPF > #include <bpf/bpf.h> > +#include <bpf/btf.h> > #include <bpf/libbpf.h> > #endif > > @@ -136,7 +141,7 @@ static struct column columns[] = { > { ALIGN_RIGHT, "Peer Address:", " ", 0, 0, 0 }, > { ALIGN_LEFT, "Port", "", 0, 0, 0 }, > { ALIGN_LEFT, "Process", "", 0, 0, 0 }, > - { ALIGN_LEFT, "Socket storage", "", 1, 0, 0 }, > + { ALIGN_LEFT, "", "", 1, 0, 0 }, > { ALIGN_LEFT, "", "", 0, 0, 0 }, > }; > > @@ -1039,11 +1044,10 @@ static int buf_update(int len) > } > > /* Append content to buffer as part of the current field */ > -__attribute__((format(printf, 1, 2))) > -static void out(const char *fmt, ...) > +static void vout(const char *fmt, va_list args) > { > struct column *f = current_field; > - va_list args; > + va_list _args; > char *pos; > int len; > > @@ -1054,18 +1058,27 @@ static void out(const char *fmt, ...) > buffer.head = buf_chunk_new(); > > again: /* Append to buffer: if we have a new chunk, print again */ > + va_copy(_args, args); > > pos = buffer.cur->data + buffer.cur->len; > - va_start(args, fmt); > > /* Limit to tail room. If we hit the limit, buf_update() will tell us */ > len = vsnprintf(pos, buf_chunk_avail(buffer.tail), fmt, args); > - va_end(args); > > if (buf_update(len)) > goto again; > } > > +__attribute__((format(printf, 1, 2))) > +static void out(const char *fmt, ...) > +{ > + va_list args; > + > + va_start(args, fmt); > + vout(fmt, args); > + va_end(args); > +} > + > static int print_left_spacing(struct column *f, int stored, int printed) > { > int s; > @@ -1213,6 +1226,9 @@ static void render_calc_width(void) > */ > c->width = min(c->width, screen_width); > > + if (c == &columns[COL_SKSTOR]) > + c->width = 1; > + > if (c->width) > first = 0; > } > @@ -3392,6 +3408,8 @@ static struct bpf_map_opts { > struct bpf_sk_storage_map_info { > unsigned int id; > int fd; > + struct bpf_map_info info; > + struct btf *btf; > } maps[MAX_NR_BPF_MAP_ID_OPTS]; > bool show_all; > struct btf *kernel_btf; > @@ -3403,6 +3421,22 @@ static void bpf_map_opts_mixed_error(void) > "ss: --bpf-maps and --bpf-map-id cannot be used together\n"); > } > > +static int bpf_maps_opts_load_btf(struct bpf_map_info *info, struct btf **btf) > +{ > + if (info->btf_value_type_id) { > + *btf = btf__load_from_kernel_by_id(info->btf_id); > + if (!*btf) { > + fprintf(stderr, "ss: failed to load BTF for map ID %u\n", > + info->id); > + return -1; > + } > + } else { > + *btf = NULL; > + } > + > + return 0; > +} > + > static int bpf_map_opts_add_all(void) > { > unsigned int i; > @@ -3418,6 +3452,7 @@ static int bpf_map_opts_add_all(void) > while (1) { > struct bpf_map_info info = {}; > uint32_t len = sizeof(info); > + struct btf *btf; > > r = bpf_map_get_next_id(id, &id); > if (r) { > @@ -3462,8 +3497,18 @@ static int bpf_map_opts_add_all(void) > continue; > } > > + r = bpf_maps_opts_load_btf(&info, &btf); > + if (r) { > + fprintf(stderr, "ss: failed to get BTF data for BPF map ID: %u\n", > + id); > + close(fd); > + goto err; > + } > + > bpf_map_opts.maps[bpf_map_opts.nr_maps].id = id; > - bpf_map_opts.maps[bpf_map_opts.nr_maps++].fd = fd; > + bpf_map_opts.maps[bpf_map_opts.nr_maps].fd = fd; > + bpf_map_opts.maps[bpf_map_opts.nr_maps].info = info; > + bpf_map_opts.maps[bpf_map_opts.nr_maps++].btf = btf; > } > > bpf_map_opts.show_all = true; > @@ -3482,6 +3527,7 @@ static int bpf_map_opts_add_id(const char *optarg) > struct bpf_map_info info = {}; > uint32_t len = sizeof(info); > size_t optarg_len; > + struct btf *btf; > unsigned long id; > unsigned int i; > char *end; > @@ -3539,8 +3585,17 @@ static int bpf_map_opts_add_id(const char *optarg) > return -1; > } > > + r = bpf_maps_opts_load_btf(&info, &btf); > + if (r) { > + fprintf(stderr, "ss: failed to get BTF data for BPF map ID: %lu\n", > + id); > + return -1; > + } > + > bpf_map_opts.maps[bpf_map_opts.nr_maps].id = id; > - bpf_map_opts.maps[bpf_map_opts.nr_maps++].fd = fd; > + bpf_map_opts.maps[bpf_map_opts.nr_maps].fd = fd; > + bpf_map_opts.maps[bpf_map_opts.nr_maps].info = info; > + bpf_map_opts.maps[bpf_map_opts.nr_maps++].btf = btf; > > return 0; > } > @@ -3549,8 +3604,23 @@ static void bpf_map_opts_destroy(void) > { > int i; > > - for (i = 0; i < bpf_map_opts.nr_maps; ++i) > + for (i = 0; i < bpf_map_opts.nr_maps; ++i) { > + btf__free(bpf_map_opts.maps[i].btf); > close(bpf_map_opts.maps[i].fd); > + } > +} > + > +static const struct bpf_sk_storage_map_info *bpf_map_opts_get_info( > + unsigned int map_id) > +{ > + unsigned int i; > + > + for (i = 0; i < bpf_map_opts.nr_maps; ++i) { > + if (bpf_map_opts.maps[i].id == map_id) > + return &bpf_map_opts.maps[i]; > + } > + > + return NULL; > } > > static inline bool bpf_map_opts_is_enabled(void) > @@ -3590,10 +3660,63 @@ static struct rtattr *bpf_map_opts_alloc_rta(void) > return stgs_rta; > } > > +static void out_bpf_sk_storage_print_fn(void *ctx, const char *fmt, va_list args) > +{ > + vout(fmt, args); > +} > + > +#define SK_STORAGE_INDENT_STR " " > + > +static void out_bpf_sk_storage(int map_id, const void *data, size_t len) > +{ > + uint32_t type_id; > + const struct bpf_sk_storage_map_info *map_info; > + struct btf_dump *dump; > + struct btf_dump_type_data_opts opts = { > + .sz = sizeof(struct btf_dump_type_data_opts), > + .indent_str = SK_STORAGE_INDENT_STR, > + .indent_level = 2, > + .emit_zeroes = 1 > + }; > + struct btf_dump_opts dopts = { > + .sz = sizeof(struct btf_dump_opts) > + }; > + int r; > + > + map_info = bpf_map_opts_get_info(map_id); > + if (!map_info) { > + fprintf(stderr, "map_id: %d: missing map info", map_id); > + return; > + } > + > + if (map_info->info.value_size != len) { > + fprintf(stderr, "map_id: %d: invalid value size, expecting %u, got %lu\n", > + map_id, map_info->info.value_size, len); > + return; > + } > + > + type_id = map_info->info.btf_value_type_id; > + > + dump = btf_dump__new(map_info->btf, out_bpf_sk_storage_print_fn, NULL, &dopts); > + if (!dump) { > + fprintf(stderr, "Failed to create btf_dump object\n"); > + return; > + } > + > + out(SK_STORAGE_INDENT_STR "map_id: %d [\n", map_id); > + r = btf_dump__dump_type_data(dump, type_id, data, len, &opts); > + if (r < 0) > + out(SK_STORAGE_INDENT_STR SK_STORAGE_INDENT_STR "failed to dump data: %d", r); > + out("\n" SK_STORAGE_INDENT_STR "]"); > + > + btf_dump__free(dump); > +} > + > static void show_sk_bpf_storages(struct rtattr *bpf_stgs) > { > struct rtattr *tb[SK_DIAG_BPF_STORAGE_MAX + 1], *bpf_stg; > - unsigned int rem; > + unsigned int rem, map_id; > + struct rtattr *value; > > for (bpf_stg = RTA_DATA(bpf_stgs), rem = RTA_PAYLOAD(bpf_stgs); > RTA_OK(bpf_stg, rem); bpf_stg = RTA_NEXT(bpf_stg, rem)) { > @@ -3605,8 +3728,13 @@ static void show_sk_bpf_storages(struct rtattr *bpf_stgs) > (struct rtattr *)bpf_stg); > > if (tb[SK_DIAG_BPF_STORAGE_MAP_ID]) { > - out("map_id:%u", > - rta_getattr_u32(tb[SK_DIAG_BPF_STORAGE_MAP_ID])); > + out("\n"); > + > + map_id = rta_getattr_u32(tb[SK_DIAG_BPF_STORAGE_MAP_ID]); > + value = tb[SK_DIAG_BPF_STORAGE_MAP_VALUE]; > + > + out_bpf_sk_storage(map_id, RTA_DATA(value), > + RTA_PAYLOAD(value)); > } > } > } > @@ -6000,6 +6128,11 @@ int main(int argc, char *argv[]) > } > } > > + if (oneline && (bpf_map_opts.nr_maps || bpf_map_opts.show_all)) { > + fprintf(stderr, "ss: --oneline, --bpf-maps, and --bpf-map-id are incompatible\n"); > + exit(-1); > + } > + I guess it would be possible to provide oneline output if we used compact-mode + omit-zeros BTF data dumping. Did you try that or is the output just too cluttered? > if (show_processes || show_threads || show_proc_ctx || show_sock_ctx) > user_ent_hash_build(); >
diff --git a/misc/ss.c b/misc/ss.c index f979b61d..6051b694 100644 --- a/misc/ss.c +++ b/misc/ss.c @@ -51,8 +51,13 @@ #include <linux/tls.h> #include <linux/mptcp.h> +#ifdef HAVE_LIBBPF +#include <linux/btf.h> +#endif + #ifdef HAVE_LIBBPF #include <bpf/bpf.h> +#include <bpf/btf.h> #include <bpf/libbpf.h> #endif @@ -136,7 +141,7 @@ static struct column columns[] = { { ALIGN_RIGHT, "Peer Address:", " ", 0, 0, 0 }, { ALIGN_LEFT, "Port", "", 0, 0, 0 }, { ALIGN_LEFT, "Process", "", 0, 0, 0 }, - { ALIGN_LEFT, "Socket storage", "", 1, 0, 0 }, + { ALIGN_LEFT, "", "", 1, 0, 0 }, { ALIGN_LEFT, "", "", 0, 0, 0 }, }; @@ -1039,11 +1044,10 @@ static int buf_update(int len) } /* Append content to buffer as part of the current field */ -__attribute__((format(printf, 1, 2))) -static void out(const char *fmt, ...) +static void vout(const char *fmt, va_list args) { struct column *f = current_field; - va_list args; + va_list _args; char *pos; int len; @@ -1054,18 +1058,27 @@ static void out(const char *fmt, ...) buffer.head = buf_chunk_new(); again: /* Append to buffer: if we have a new chunk, print again */ + va_copy(_args, args); pos = buffer.cur->data + buffer.cur->len; - va_start(args, fmt); /* Limit to tail room. If we hit the limit, buf_update() will tell us */ len = vsnprintf(pos, buf_chunk_avail(buffer.tail), fmt, args); - va_end(args); if (buf_update(len)) goto again; } +__attribute__((format(printf, 1, 2))) +static void out(const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + vout(fmt, args); + va_end(args); +} + static int print_left_spacing(struct column *f, int stored, int printed) { int s; @@ -1213,6 +1226,9 @@ static void render_calc_width(void) */ c->width = min(c->width, screen_width); + if (c == &columns[COL_SKSTOR]) + c->width = 1; + if (c->width) first = 0; } @@ -3392,6 +3408,8 @@ static struct bpf_map_opts { struct bpf_sk_storage_map_info { unsigned int id; int fd; + struct bpf_map_info info; + struct btf *btf; } maps[MAX_NR_BPF_MAP_ID_OPTS]; bool show_all; struct btf *kernel_btf; @@ -3403,6 +3421,22 @@ static void bpf_map_opts_mixed_error(void) "ss: --bpf-maps and --bpf-map-id cannot be used together\n"); } +static int bpf_maps_opts_load_btf(struct bpf_map_info *info, struct btf **btf) +{ + if (info->btf_value_type_id) { + *btf = btf__load_from_kernel_by_id(info->btf_id); + if (!*btf) { + fprintf(stderr, "ss: failed to load BTF for map ID %u\n", + info->id); + return -1; + } + } else { + *btf = NULL; + } + + return 0; +} + static int bpf_map_opts_add_all(void) { unsigned int i; @@ -3418,6 +3452,7 @@ static int bpf_map_opts_add_all(void) while (1) { struct bpf_map_info info = {}; uint32_t len = sizeof(info); + struct btf *btf; r = bpf_map_get_next_id(id, &id); if (r) { @@ -3462,8 +3497,18 @@ static int bpf_map_opts_add_all(void) continue; } + r = bpf_maps_opts_load_btf(&info, &btf); + if (r) { + fprintf(stderr, "ss: failed to get BTF data for BPF map ID: %u\n", + id); + close(fd); + goto err; + } + bpf_map_opts.maps[bpf_map_opts.nr_maps].id = id; - bpf_map_opts.maps[bpf_map_opts.nr_maps++].fd = fd; + bpf_map_opts.maps[bpf_map_opts.nr_maps].fd = fd; + bpf_map_opts.maps[bpf_map_opts.nr_maps].info = info; + bpf_map_opts.maps[bpf_map_opts.nr_maps++].btf = btf; } bpf_map_opts.show_all = true; @@ -3482,6 +3527,7 @@ static int bpf_map_opts_add_id(const char *optarg) struct bpf_map_info info = {}; uint32_t len = sizeof(info); size_t optarg_len; + struct btf *btf; unsigned long id; unsigned int i; char *end; @@ -3539,8 +3585,17 @@ static int bpf_map_opts_add_id(const char *optarg) return -1; } + r = bpf_maps_opts_load_btf(&info, &btf); + if (r) { + fprintf(stderr, "ss: failed to get BTF data for BPF map ID: %lu\n", + id); + return -1; + } + bpf_map_opts.maps[bpf_map_opts.nr_maps].id = id; - bpf_map_opts.maps[bpf_map_opts.nr_maps++].fd = fd; + bpf_map_opts.maps[bpf_map_opts.nr_maps].fd = fd; + bpf_map_opts.maps[bpf_map_opts.nr_maps].info = info; + bpf_map_opts.maps[bpf_map_opts.nr_maps++].btf = btf; return 0; } @@ -3549,8 +3604,23 @@ static void bpf_map_opts_destroy(void) { int i; - for (i = 0; i < bpf_map_opts.nr_maps; ++i) + for (i = 0; i < bpf_map_opts.nr_maps; ++i) { + btf__free(bpf_map_opts.maps[i].btf); close(bpf_map_opts.maps[i].fd); + } +} + +static const struct bpf_sk_storage_map_info *bpf_map_opts_get_info( + unsigned int map_id) +{ + unsigned int i; + + for (i = 0; i < bpf_map_opts.nr_maps; ++i) { + if (bpf_map_opts.maps[i].id == map_id) + return &bpf_map_opts.maps[i]; + } + + return NULL; } static inline bool bpf_map_opts_is_enabled(void) @@ -3590,10 +3660,63 @@ static struct rtattr *bpf_map_opts_alloc_rta(void) return stgs_rta; } +static void out_bpf_sk_storage_print_fn(void *ctx, const char *fmt, va_list args) +{ + vout(fmt, args); +} + +#define SK_STORAGE_INDENT_STR " " + +static void out_bpf_sk_storage(int map_id, const void *data, size_t len) +{ + uint32_t type_id; + const struct bpf_sk_storage_map_info *map_info; + struct btf_dump *dump; + struct btf_dump_type_data_opts opts = { + .sz = sizeof(struct btf_dump_type_data_opts), + .indent_str = SK_STORAGE_INDENT_STR, + .indent_level = 2, + .emit_zeroes = 1 + }; + struct btf_dump_opts dopts = { + .sz = sizeof(struct btf_dump_opts) + }; + int r; + + map_info = bpf_map_opts_get_info(map_id); + if (!map_info) { + fprintf(stderr, "map_id: %d: missing map info", map_id); + return; + } + + if (map_info->info.value_size != len) { + fprintf(stderr, "map_id: %d: invalid value size, expecting %u, got %lu\n", + map_id, map_info->info.value_size, len); + return; + } + + type_id = map_info->info.btf_value_type_id; + + dump = btf_dump__new(map_info->btf, out_bpf_sk_storage_print_fn, NULL, &dopts); + if (!dump) { + fprintf(stderr, "Failed to create btf_dump object\n"); + return; + } + + out(SK_STORAGE_INDENT_STR "map_id: %d [\n", map_id); + r = btf_dump__dump_type_data(dump, type_id, data, len, &opts); + if (r < 0) + out(SK_STORAGE_INDENT_STR SK_STORAGE_INDENT_STR "failed to dump data: %d", r); + out("\n" SK_STORAGE_INDENT_STR "]"); + + btf_dump__free(dump); +} + static void show_sk_bpf_storages(struct rtattr *bpf_stgs) { struct rtattr *tb[SK_DIAG_BPF_STORAGE_MAX + 1], *bpf_stg; - unsigned int rem; + unsigned int rem, map_id; + struct rtattr *value; for (bpf_stg = RTA_DATA(bpf_stgs), rem = RTA_PAYLOAD(bpf_stgs); RTA_OK(bpf_stg, rem); bpf_stg = RTA_NEXT(bpf_stg, rem)) { @@ -3605,8 +3728,13 @@ static void show_sk_bpf_storages(struct rtattr *bpf_stgs) (struct rtattr *)bpf_stg); if (tb[SK_DIAG_BPF_STORAGE_MAP_ID]) { - out("map_id:%u", - rta_getattr_u32(tb[SK_DIAG_BPF_STORAGE_MAP_ID])); + out("\n"); + + map_id = rta_getattr_u32(tb[SK_DIAG_BPF_STORAGE_MAP_ID]); + value = tb[SK_DIAG_BPF_STORAGE_MAP_VALUE]; + + out_bpf_sk_storage(map_id, RTA_DATA(value), + RTA_PAYLOAD(value)); } } } @@ -6000,6 +6128,11 @@ int main(int argc, char *argv[]) } } + if (oneline && (bpf_map_opts.nr_maps || bpf_map_opts.show_all)) { + fprintf(stderr, "ss: --oneline, --bpf-maps, and --bpf-map-id are incompatible\n"); + exit(-1); + } + if (show_processes || show_threads || show_proc_ctx || show_sock_ctx) user_ent_hash_build();
ss is able to print the map ID(s) for which a given socket has BPF socket-local storage defined (using --bpf-maps or --bpf-map-id=). However, the actual content of the map remains hidden. This change aims to pretty-print the socket-local storage content following the socket details, similar to what `bpftool map dump` would do. The exact output format is inspired by drgn, while the BTF data processing is similar to bpftool's. ss will use libbpf's btf_dump__dump_type_data() to ease pretty-printing of binary data. This requires out_bpf_sk_storage_print_fn() as a print callback function used by btf_dump__dump_type_data(). vout() is also introduced, which is similar to out() but accepts a va_list as parameter. COL_SKSTOR's header is replaced with an empty string, as it doesn't need to be printed anymore; it's used as a "virtual" column to refer to the socket-local storage dump, which will be printed under the socket information. The column's width is fixed to 1, so it doesn't mess up ss' output. ss' output remains unchanged unless --bpf-maps or --bpf-map-id= is used, in which case each socket containing BPF local storage will be followed by the content of the storage before the next socket's info is displayed. Signed-off-by: Quentin Deslandes <qde@naccy.de> --- misc/ss.c | 157 +++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 145 insertions(+), 12 deletions(-)