perf/Documentation/perf-intel-pt.txt

16 Intel Processor Trace (Intel PT) is an extension of Intel Architecture that
22 Intel PT is first supported in Intel Core M and 5th generation Intel Core
39 The main distinguishing feature of Intel PT is that the decoder can determine
40 the exact flow of software execution.  Intel PT can be used to understand why
42 software does not have to be recompiled, so Intel PT works with debug or release
47 A limitation of Intel PT is that it produces huge amounts of trace data
60 The simplest thing to do with Intel PT is userspace profiling of small programs.
94 Also note that the coarseness of Intel PT timing information will start to
154 Because Intel PT does not update the cycle count on every branch or instruction,
181 Refer to 'new snapshot option' and 'Intel PT modes of operation' further below.
199 The Intel PT kernel driver creates a new PMU for Intel PT.  PMU events are
254 'h', 'G' and 'H' are for virtualization which is not supported by Intel PT.
255 'p' is also not relevant to Intel PT.  So only options 'u' and 'k' are
256 meaningful for Intel PT.
286 Manuals, Chapter 36 Intel Processor Trace, defined new Intel PT features.
475 To select Intel PT "sampling" the AUX area sampling option can be used:
483 In addition, the Intel PT event to sample must be defined e.g.
487 Samples on other events will be created containing Intel PT data e.g. the
488 following will create Intel PT samples on the branch-misses event, note the
509 	Intel PT sample size (%zu) may be too small for PSB period (%zu)
548 	Intel PT snapshot size: %zu
554 Intel PT buffer size is specified by an addition to the -m option e.g.
563 The default auxtrace mmap size for Intel PT is 4MiB/page_size for privileged users
584 Intel PT modes of operation
587 Intel PT can be used in 3 modes:
596 Sample mode attaches a Intel PT sample to other events e.g.
628 The 3 Intel PT modes of operation cannot be used together.
655 Intel PT and build ids
659 for executables for all addresses sampled.  Deliberately, Intel PT is not
668 If the perf.data file contains Intel PT data, that is the same as:
743 information to decode Intel PT in per-cpu mode, and potentially workload-only
748 be possible to decode Intel PT in per-cpu mode.
754 The sched_switch tracepoint is used to provide side-band data for Intel PT
834 cannot be matched against the Intel PT trace.
920 The flags supported by Intel PT are:
931 must be preceded by either '+' or '-'. The flags support by Intel PT are:
947 The timing information included with Intel PT does not give the time of every
952 For Intel PT, the default period is 100us.
956 In the case of Intel PT that is the same as a period of 1 and a unit of
977 'ls' and then add a call chain derived from the Intel PT trace:
989 late timestamps.  Because the Intel PT trace is synchronized by timestamps,
1002 Because Intel PT sample mode uses a different sample type to the list above,
1003 Large PEBS is not used with Intel PT sample mode. To avoid Large PEBS in other
1067 When -D is used, Intel PT packets are displayed.  The packet decoder does not
1075 To disable the display of Intel PT packets, combine the -D option with
1095 Below is an example of using Intel PT with autofdo.  It requires autofdo
1121 Note there is currently no advantage to using Intel PT instead of LBR, but
1125 PEBS via Intel PT
1128 Some hardware has the feature to redirect PEBS records to the Intel PT trace.
1135 To display PEBS events from the Intel PT trace, use the itrace 'o' option e.g.