Re: [PATCH] perf list: Hide deprecated events by default

From: Jin, Yao
Date: Wed Oct 16 2019 - 06:22:11 EST




On 10/16/2019 3:27 PM, Jiri Olsa wrote:
On Wed, Oct 16, 2019 at 08:59:13AM +0800, Jin, Yao wrote:


On 10/15/2019 5:14 PM, Jiri Olsa wrote:
On Tue, Oct 15, 2019 at 10:53:57AM +0800, Jin Yao wrote:
There are some deprecated events listed by perf list. But we can't remove
them from perf list with ease because some old scripts may use them.

Deprecated events are old names of renamed events. When an event gets
renamed the old name is kept around for some time and marked with
Deprecated. The newer Intel event lists in the tree already have these
headers.

So we need to keep them in the event list, but provide a new option to
show them. The new option is "--deprecated".

With this patch, the deprecated events are hidden by default but they can
be displayed when option "--deprecated" is enabled.

not sure it's wise to hide them, because people will not read man page
to find --deprecated option, they will rather complain right away ;-)

how about to display them as another topic, like:

pipeline:
...
uncore:
...
deprecated:
...

jirka


Hi Jiri,

I don't know if we add a new topic "deprecated" in perf list output, does
the old script need to be modified as well?

Say the events are moved to the "deprecated" section, I just guess the
script needs the modification.

That's just my personal guess. :)

i did not mean adding new topic all the way down,
just to display the deprecated events like that

jirka


Sorry, maybe I misunderstood what you suggested. Correct me if my understanding is wrong.

Now the perf list output is like:

pipeline:
event1
event2
uncore:
event3
event4

My understanding for your suggestion is, we need to add "deprecated", for example:

pipeline:
event1
event2
uncore:
event4
deprecated:
event3

In above example, I assume the event3 is deprecated.

So my worry is, the user's old script may not find the event3 if we move it from "uncore" to "deprecated". Maybe I'm worried a lot. :(

Thanks
Jin Yao