gdb: Branch Trace Configuration Format
E.20 Branch Trace Configuration Format
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For each inferior thread, GDB can obtain the branch trace configuration
using the 'qXfer:btrace-conf:read' (qXfer btrace-conf read)
packet.
The configuration describes the branch trace format and configuration
settings for that format. The following information is described:
'bts'
This thread uses the "Branch Trace Store" (BTS) format.
'size'
The size of the BTS ring buffer in bytes.
'pt'
This thread uses the "Intel Processor Trace" (Intel PT) format.
'size'
The size of the Intel PT ring buffer in bytes.
GDB must be linked with the Expat library to support XML branch trace
configuration discovery. Expat.
The formal DTD for the branch trace configuration format is given
below:
<!ELEMENT btrace-conf (bts?, pt?)>
<!ATTLIST btrace-conf version CDATA #FIXED "1.0">
<!ELEMENT bts EMPTY>
<!ATTLIST bts size CDATA #IMPLIED>
<!ELEMENT pt EMPTY>
<!ATTLIST pt size CDATA #IMPLIED>