bianbu-linux-6.6/tools/bpf
Tonghao Zhang 377c16fa3f bpftool: profile online CPUs instead of possible
The number of online cpu may be not equal to possible cpu.
"bpftool prog profile" can not create pmu event on possible
but on online cpu.

$ dmidecode -s system-product-name
PowerEdge R620
$ cat /sys/devices/system/cpu/possible
0-47
$ cat /sys/devices/system/cpu/online
0-31

Disable cpu dynamically:
$ echo 0 > /sys/devices/system/cpu/cpuX/online

If one cpu is offline, perf_event_open will return ENODEV.
To fix this issue:
* check value returned and skip offline cpu.
* close pmu_fd immediately on error path, avoid fd leaking.

Fixes: 47c09d6a9f ("bpftool: Introduce "prog profile" command")
Signed-off-by: Tonghao Zhang <tong@infragraf.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Song Liu <song@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20230202131701.29519-1-tong@infragraf.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-02-02 22:20:14 -08:00
..
bpftool bpftool: profile online CPUs instead of possible 2023-02-02 22:20:14 -08:00
resolve_btfids tools/resolve_btfids: Alter how HOSTCC is forced 2023-01-25 18:28:14 +01:00
runqslower tools: runqslower: Build and use lightweight bootstrap version of bpftool 2022-07-15 12:01:30 -07:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
bpf_asm.c docs: networking: convert filter.txt to ReST 2020-04-28 14:39:46 -07:00
bpf_dbg.c bpf: Simplify the calculation of variables 2021-03-04 19:24:53 -08:00
bpf_exp.l bpf: fix cbpf parser bug for octal numbers 2018-06-03 07:46:55 -07:00
bpf_exp.y tools, bpf_asm: Exit non-zero on errors 2021-02-26 22:53:50 +01:00
bpf_jit_disasm.c tools bpf_jit_disasm: Fix compilation error with new binutils 2022-08-01 15:30:48 -03:00
Makefile tools bpf_jit_disasm: Don't display disassembler-four-args feature test 2022-08-01 15:31:51 -03:00