X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=README;fp=README;h=1a7cea16e4ca49e72ae957e1d3723edb8d746a19;hb=a3a8ea221c9674f6a30b75aee373c95c0556d769;hp=583d0e024864d2e37fd22a86d847ec955539b1d7;hpb=da4e23320ee3bed6a19fe29c8a0b8b78387be7f3;p=lttng-modules.git

diff --git a/README b/README
index 583d0e02..1a7cea16 100644
--- a/README
+++ b/README
@@ -46,3 +46,10 @@ Support for LTTng 0.x clocks will be added back soon into LTTng 2.0.  Please
 note that lttng-modules 2.0 can build on a Linux kernel patched with the LTTng
 0.x patchset, but the lttng-modules 2.0 replace the lttng-modules 0.x, so both
 tracers cannot be installed at the same time for a given kernel version.
+
+* Note about Perf PMU counters support
+
+Each PMU counter has its zero value set when it is attached to a context with
+add-context. Therefore, it is normal that the same counters attached to both the
+stream context and event context show different values for a given event; what
+matters is that they increment at the same rate.