linux/tools/lib
Andrii Nakryiko 597fbc4682 libbpf: make RINGBUF map size adjustments more eagerly
Make libbpf adjust RINGBUF map size (rounding it up to closest power-of-2
of page_size) more eagerly: during open phase when initializing the map
and on explicit calls to bpf_map__set_max_entries().

Such approach allows user to check actual size of BPF ringbuf even
before it's created in the kernel, but also it prevents various edge
case scenarios where BPF ringbuf size can get out of sync with what it
would be in kernel. One of them (reported in [0]) is during an attempt
to pin/reuse BPF ringbuf.

Move adjust_ringbuf_sz() helper closer to its first actual use. The
implementation of the helper is unchanged.

Also make detection of whether bpf_object is already loaded more robust
by checking obj->loaded explicitly, given that map->fd can be < 0 even
if bpf_object is already loaded due to ability to disable map creation
with bpf_map__set_autocreate(map, false).

  [0] Closes: https://github.com/libbpf/libbpf/pull/530

Fixes: 0087a681fa ("libbpf: Automatically fix up BPF_MAP_TYPE_RINGBUF size, if necessary")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220715230952.2219271-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 10:01:20 -07:00
..
api Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
bpf libbpf: make RINGBUF map size adjustments more eagerly 2022-07-19 10:01:20 -07:00
perf libperf evsel: Open shouldn't leak fd on failure 2022-06-19 10:41:43 -03:00
subcmd libsubcmd: Fix OPTION_GROUP sorting 2022-04-22 12:32:01 +02:00
symbol libsymbols kallsyms: Move hex2u64 out of header 2020-05-05 16:35:32 -03:00
thermal tools/lib/thermal: remove unneeded semicolon 2022-05-19 12:11:52 +02:00
traceevent libtraceevent: Add __rel_loc relative location attribute support 2021-12-06 15:37:22 -05:00
argv_split.c
bitmap.c bitmap: Fix return values to be unsigned 2022-06-03 06:52:58 -07:00
ctype.c
find_bit.c tools: sync tools/bitmap with mother linux 2022-01-15 08:47:31 -08:00
hweight.c
list_sort.c tools lib: Adopt list_sort() from the kernel sources 2021-10-20 10:30:59 -03:00
rbtree.c tools/: replace HTTP links with HTTPS ones 2020-08-07 11:33:21 -07:00
slab.c tools: Move gfp.h and slab.h from radix-tree to lib 2022-02-20 08:44:37 +02:00
str_error_r.c
string.c tools lib: Adopt memchr_inv() from kernel 2020-11-27 08:34:52 -03:00
vsprintf.c
zalloc.c