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

[Wangnan (F)]

On 2017/10/9 22:39, Jiri Olsa wrote:
> On Mon, Oct 09, 2017 at 11:12:58AM -0300, Arnaldo Carvalho de Melo wrote:
> > Em Mon, Oct 09, 2017 at 07:07:29AM -0700, Andi Kleen escreveu:
> > > On Mon, Oct 09, 2017 at 03:41:51PM +0200, Jiri Olsa wrote:
> > > > 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:
> > > > > > On Tue, Oct 03, 2017 at 01:06:05PM -0300, Arnaldo Carvalho de Melo wrote:
> > > > > > > Em Tue, Sep 12, 2017 at 12:56:43PM -0700, Andi Kleen escreveu:
> > > > > > > > From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> > > > > > > >
> > > > > > > > There are still problems with BPF misinterpreting some events
> > > > > > > > that include .c. An earlier fix made it work for stand alone
> > > > > > > > aliases, but it still fails for more complex constructs.
> > > > > > > Hi Wang, Jiri,
> > > > > > >
> > > > > > > 	Can you please take a look at this and see if there is something
> > > > > > > we can do to help Andi?
> > > > > > >
> > > > > > > - Arnaldo
> > > > > > >   
> > > > > > > > REJECT keeps trying and trying a shorter string until
> > > > > > > > .c is matched and it appears like a valid BPF path.
> > > > > > > >
> > > > > > > > % perf stat -e cpu/uops_executed.core,cmask=1/ true
> > > > > > > > bpf: builtin compilation failed: -95, try external compiler
> > > > > > > > ERROR: problems with path cpu/uops_executed.c: No such file or directory
> > > > > > > > event syntax error: 'cpu/uops_executed.core,cmask=1/'
> > > > > > > >                       \___ Failed to load cpu/uops_executed.c from source: Error when compiling BPF scriptlet
> > > > > > > >
> > > > > > > > I tried to fix it, but it exceeds my flex knowledge, because
> > > > > > > > REJECT does not interact well with BEGIN states.
> > > > > > > >
> > > > > > > > The BPF syntax in its current form really causes an ambigious
> > > > > > > > grammar.
> > > > > > 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
> > > Ok. If it works it's fine for me.
> well it works, but it means that bpf file cannot contains any directory
> part.. which im not sure is ok with bpf folks ;-) anyone?

Sorry I didn't see this thread these days.

Do you think adding a special escape character to suppress BPF
name parsing in a event is a good idea? for example:

% perf stat -e cpu/uops_executed.core,cmask=1/ true
bpf: builtin compilation failed: -95, try external compiler
ERROR: problems with path cpu/uops_executed.c: No such file or directory
event syntax error: 'cpu/uops_executed.core,cmask=1/'
                     \___ Failed to load cpu/uops_executed.c from 
source: Error when compiling BPF scriptlet. Add a leading '@' to avoid 
BPF syntax

% perf stat -e @cpu/uops_executed.core,cmask=1/ true
...