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Subject[PATCH v2 4/6] Documentation: coresight: Turn numbered subsections into real subsections
Date
This is to allow them to be referenced in a later commit. There was
also a mistake where sysFS was introduced as section 2, but numbered
as section 1. And vice versa for 'Using perf framework'. This can't
happen with unnumbered sections.

Signed-off-by: James Clark <james.clark@arm.com>
---
Documentation/trace/coresight/coresight.rst | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/Documentation/trace/coresight/coresight.rst b/Documentation/trace/coresight/coresight.rst
index a15571d96cc8..db66ff45ff4c 100644
--- a/Documentation/trace/coresight/coresight.rst
+++ b/Documentation/trace/coresight/coresight.rst
@@ -339,7 +339,8 @@ Preference is given to the former as using the sysFS interface
requires a deep understanding of the Coresight HW. The following sections
provide details on using both methods.

-1) Using the sysFS interface:
+Using the sysFS interface
+~~~~~~~~~~~~~~~~~~~~~~~~~

Before trace collection can start, a coresight sink needs to be identified.
There is no limit on the amount of sinks (nor sources) that can be enabled at
@@ -446,7 +447,8 @@ wealth of possibilities that coresight provides.
Instruction 0 0x8026B588 E8BD8000 true LDM sp!,{pc}
Timestamp Timestamp: 17107041535

-2) Using perf framework:
+Using perf framework
+~~~~~~~~~~~~~~~~~~~~

Coresight tracers are represented using the Perf framework's Performance
Monitoring Unit (PMU) abstraction. As such the perf framework takes charge of
@@ -495,7 +497,11 @@ More information on the above and other example on how to use Coresight with
the perf tools can be found in the "HOWTO.md" file of the openCSD gitHub
repository [#third]_.

-2.1) AutoFDO analysis using the perf tools:
+Advanced perf framework usage
+-----------------------------
+
+AutoFDO analysis using the perf tools
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

perf can be used to record and analyze trace of programs.

@@ -513,7 +519,8 @@ The --itrace option controls the type and frequency of synthesized events
Note that only 64-bit programs are currently supported - further work is
required to support instruction decode of 32-bit Arm programs.

-2.2) Tracing PID
+Tracing PID
+~~~~~~~~~~~

The kernel can be built to write the PID value into the PE ContextID registers.
For a kernel running at EL1, the PID is stored in CONTEXTIDR_EL1. A PE may
@@ -547,7 +554,7 @@ wants to trace PIDs for both host and guest, the two configs "contextid1" and


Generating coverage files for Feedback Directed Optimization: AutoFDO
----------------------------------------------------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

'perf inject' accepts the --itrace option in which case tracing data is
removed and replaced with the synthesized events. e.g.
--
2.28.0
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