[RESEND PATCH V4 2/4] Documentations: Add explanations of the case for non-configurable masters
From: Chunyan Zhang <hidden>
Date: 2016-03-08 06:36:25
Also in:
linux-arm-kernel, lkml
Subsystem:
documentation, the rest, tracing · Maintainers:
Jonathan Corbet, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
For some STM hardware (e.g. ARM CoreSight STM), the masterID associated to a source is set at the hardware level and not user configurable. Since the masterID information isn't available to SW, introducing a new value of -1 to reflect this reality. Signed-off-by: Chunyan Zhang <redacted> --- Documentation/trace/stm.txt | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/Documentation/trace/stm.txt b/Documentation/trace/stm.txt
index ea035f9..f03bc2b 100644
--- a/Documentation/trace/stm.txt
+++ b/Documentation/trace/stm.txt@@ -47,6 +47,12 @@ through 127 in it. Now, any producer (trace source) identifying itself with "user" identification string will be allocated a master and channel from within these ranges. +$ cat /config/stp-policy/dummy_stm.my-policy/user/masters +-1 -1 + +Would indicate the masters for this rule are set in hardware and +not configurable in user space. + These rules can be nested, for example, one can define a rule "dummy" under "user" directory from the example above and this new rule will be used for trace sources with the id string of "user/dummy".
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1.9.1