ecc4c5614b
Previously these were being ignored, sometimes silently.
Stop doing that, emitting debug messages and handling the errors.
Testing it:
$ cat ~/.perfconfig
cat: /home/acme/.perfconfig: No such file or directory
$ perf stat -e cycles usleep 1
Performance counter stats for 'usleep 1':
938,996 cycles:u
0.003813731 seconds time elapsed
$ perf top --stdio
Error:
You may not have permission to collect system-wide stats.
Consider tweaking /proc/sys/kernel/perf_event_paranoid,
<SNIP>
[ perf record: Captured and wrote 0.019 MB perf.data (7 samples) ]
[acme@jouet linux]$ perf report --stdio
# To display the perf.data header info, please use --header/--header-only options.
# Overhead Command Shared Object Symbol
# ........ ....... ................. .........................
71.77% usleep libc-2.24.so [.] _dl_addr
27.07% usleep ld-2.24.so [.] _dl_next_ld_env_entry
1.13% usleep [kernel.kallsyms] [k] page_fault
$
$ touch ~/.perfconfig
$ ls -la ~/.perfconfig
-rw-rw-r--. 1 acme acme 0 Jan 27 12:14 /home/acme/.perfconfig
$
$ perf stat -e instructions usleep 1
Performance counter stats for 'usleep 1':
244,610 instructions:u
0.000805383 seconds time elapsed
$
[root@jouet ~]# chown acme.acme ~/.perfconfig
[root@jouet ~]# perf stat -e cycles usleep 1
Warning: File /root/.perfconfig not owned by current user or root, ignoring it.
Performance counter stats for 'usleep 1':
937,615 cycles
0.000836931 seconds time elapsed
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-j2rq96so6xdqlr8p8rd6a3jx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.