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Documentation: coresight: Turn numbered subsections into real subsections 

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>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220511144601.2257870-3-james.clark@arm.com
This commit is contained in:
James Clark 2022-05-11 15:45:59 +01:00 committed by Suzuki K Poulose
parent 2d693ed436
commit bcc5834fba
1 changed files with 12 additions and 5 deletions
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17
Documentation/trace/coresight/coresight.rst
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@ -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.