On Thu, Jun 10, 2021 at 03:59:15PM -0400, Steven Rostedt wrote:

On Thu, 10 Jun 2021 21:08:32 +0200
Jiri Olsa [off-list ref] wrote:

quoted

Michael did the libtraceevent detection and dynamic linking support:
  https://lore.kernel.org/linux-perf-users/20210428092023.4009-1-mpetlan@redhat.com/ (local)

I think we should have that in Fedora/RHEL rpms already, or it's on the way.

The detection code could be change to contain things we need.

Or it can also be changed to export the version too?

LIBTRACEEVENT_VERSION = $(shell pkg-config --modversion libtraceevent | perl -e '$ver=<>; @v=split /,/,$ver; printf "%d\n", $v[0] * 255 * 255 | $v[1] * 255 | $v[2];')

-DLIBTRACEFS_VERSION=$(LIBTRACEEVENT_VERSION)

so the feature detection just gives out on/off answers,
but we can easily put above to perf's makefile

jirka

Then in C have:

#define VERSION(a,b,c) ((a)*255*255|(b)*255|(c))

#if LIBTRACEEVENT_VERSION >= VERSION(1,2,3)

To test if the libtraceevent feature is available?

-- Steve