Re: [PATCH 2/2] perf, tools: Don't force MetricExprs to lower case

Arnaldo Carvalho de Melo
2017-10-09T14:09:48Z

Em Mon, Oct 09, 2017 at 03:41:51PM +0200, Jiri Olsa escreveu:
> On Wed, Oct 04, 2017 at 09:27:11AM -0700, Andi Kleen wrote:
> > On Wed, Oct 04, 2017 at 12:30:52PM +0200, Jiri Olsa wrote:
> > > right, it looks like we allow whole path (including / char)
> > > for BPF file, which messes up with out pmu/.../ syntax

> > > do we need that? (Cc-ed some bpf folks)

> > > if not attached patch seems to fix things.. otherwise
> > > we need to come up with another fix

> > I tried similar patches, but I always ran into more complex
> > situations where it still matched incorrectly.

> > e.g. try it with cpu/uops_executed.core,... vs uops_executed.core

> hm, both works for me with the change:

> perf stat -e cpu/uops_executed.core/ ls
> perf stat -e uops_executed.core ls

> > The only real fix would be probably to add some unique
> > prefix for BPF, but that would break all existing users.

> yea, there was no response from bpf folks, but it's probably not an option

> how about checking if the file exist like below..

Works well for me, Jiri, I found a problem in the last case, can you take a look?

[root@jouet bpf]# perf stat -e cpu/uops_executed.core/,uops_executed.core sleep 1

Performance counter stats for 'sleep 1':

1,094,963 cpu/uops_executed.core/
1,094,963 uops_executed.core

1.001925575 seconds time elapsed

[root@jouet bpf]# perf stat -e uops_executed.core sleep 1

Performance counter stats for 'sleep 1':

2,309,245 uops_executed.core

1.003314897 seconds time elapsed

[root@jouet bpf]# perf stat -e cpu/uops_executed.core/ sleep 1

Performance counter stats for 'sleep 1':

1,664,618 cpu/uops_executed.core/

1.002284214 seconds time elapsed

[root@jouet bpf]# cat sys_read.c
#define SEC(NAME) __attribute__((section(NAME), used))
SEC("func=sys_read")
int bpf_func__sys_read(void *ctx)
{
return 1;
}
char _license[] SEC("license") = "GPL";
int _version SEC("version") = LINUX_VERSION_CODE;
[root@jouet bpf]# perf trace --no-syscalls -e sys_read.c/max-stack=5/ sleep 1
bpf: builtin compilation failed: -95, try external compiler
0.000 perf_bpf_probe:func:(ffffffffb7263190))
sys_read ([kernel.kallsyms])
entry_SYSCALL_64_fastpath ([kernel.kallsyms])
__read (/usr/lib64/ld-2.25.so)
_dl_map_object (/usr/lib64/ld-2.25.so)
[root@jouet bpf]# perf trace --no-syscalls -e sys_read.c sleep 1
bpf: builtin compilation failed: -95, try external compiler
0.000 perf_bpf_probe:func:(ffffffffb7263190))
[root@jouet bpf]#

[root@jouet bpf]# perf stat -e UOPS_EXECUTED.CORE sleep 1

Performance counter stats for 'sleep 1':

1,205,347 UOPS_EXECUTED.CORE

1.001694225 seconds time elapsed

But I noticed this problem:

[root@jouet bpf]# perf stat -e cpu/uops_executed.core/,uops_executed.core,cpu/UOPS_EXECUTED.CORE sleep 1
event syntax error: '..d=48;5;232;38;5;3:or=48;5;232;38;5;9:mi=01;05;37;41:su=48;5;196;38;5;15:sg=48;5;11;38;5;16:ca=48;5;196;38;5;226:IY�'
\___ parser error
Run 'perf list' for a list of valid events

Usage: perf stat [<options>] [<command>]

-e, --event <event> event selector. use 'perf list' to list available events
[root@jouet bpf]#