Enable perf PMU counters by raw ID

[lttng-tools.git] / doc / man / lttng-add-context.1.txt

diff --git a/doc/man/lttng-add-context.1.txt b/doc/man/lttng-add-context.1.txt
index f995a7fbe2fd629f1091c68427edc30fc3410db8..a1e0fe78f14035015e00c7bd4185b9f3f7a2b732 100644 (file)
--- a/doc/man/lttng-add-context.1.txt
+++ b/doc/man/lttng-add-context.1.txt
@@ -45,6 +45,15 @@ per-thread (`perf:thread:` prefix) counters. Currently, per-CPU counters
 can only be used in the Linux kernel tracing domain, while per-thread
 counters can only be used in the user space tracing domain.
 
+It is also possible to enable PMU counters by raw ID using the
+`perf:cpu:raw:r<N>:<name>` or `perf:thread:raw:r<N>:<name>` format for
+the kernel and user-space respectively. `<N>` is a hexadecimal event
+descriptor which is the same format as used by perf-record(1): a
+concatenation of the `Umask value` and `Event number` provided by the
+processor's manufacturer. The possible values for this field are
+processor-specific. The `<name>` field is used to associate a clearer
+name to the counter.
+
 Application-specific context fields can be added to a channel using the
 following syntax: