linux-stable.git/tools/perf/util/intel-pt-decoder, branch v5.16.2

perf intel-pt: Fix missing 'instruction' events with 'q' option

2021-12-11T11:19:47+00:00

FUP packets contain IP information, which makes them also an 'instruction'
event in 'hop' mode i.e. the itrace 'q' option.  That wasn't happening, so
restructure the logic so that FUP events are added along with appropriate
'instruction' and 'branch' events.

Fixes: 7c1b16ba0e26e6 ("perf intel-pt: Add support for decoding FUP/TIP only")
Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-7-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Fix next 'err' value, walking trace

2021-12-11T11:19:47+00:00

Code after label 'next:' in intel_pt_walk_trace() assumes 'err' is zero,
but it may not be, if arrived at via a 'goto'. Ensure it is zero.

Fixes: 7c1b16ba0e26e6 ("perf intel-pt: Add support for decoding FUP/TIP only")
Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Fix state setting when receiving overflow (OVF) packet

2021-12-11T11:19:47+00:00

An overflow (OVF packet) is treated as an error because it represents a
loss of trace data, but there is no loss of synchronization, so the packet
state should be INTEL_PT_STATE_IN_SYNC not INTEL_PT_STATE_ERR_RESYNC.

To support that, some additional variables must be reset, and the FUP
packet that may follow OVF is treated as an FUP event.

Fixes: f4aa081949e7b6 ("perf tools: Add Intel PT decoder")
Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Fix intel_pt_fup_event() assumptions about setting state type

2021-12-11T11:19:47+00:00

intel_pt_fup_event() assumes it can overwrite the state type if there has
been an FUP event, but this is an unnecessary and unexpected constraint on
callers.

Fix by touching only the state type flags that are affected by an FUP
event.

Fixes: a472e65fc490a ("perf intel-pt: Add decoder support for ptwrite and power event packets")
Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Fix sync state when a PSB (synchronization) packet is found

2021-12-11T11:19:47+00:00

When syncing, it may be that branch packet generation is not enabled at
that point, in which case there will not immediately be a control-flow
packet, so some packets before a control flow packet turns up, get
ignored.  However, the decoder is in sync as soon as a PSB is found, so
the state should be set accordingly.

Fixes: f4aa081949e7b6 ("perf tools: Add Intel PT decoder")
Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Fix some PGE (packet generation enable/control flow packets) usage

2021-12-11T11:19:47+00:00

Packet generation enable (PGE) refers to whether control flow (COFI)
packets are being produced.

PGE may be false even when branch-tracing is enabled, due to being
out-of-context, or outside a filter address range.  Fix some missing PGE
usage.

Fixes: 7c1b16ba0e26e6 ("perf intel-pt: Add support for decoding FUP/TIP only")
Fixes: 839598176b0554 ("perf intel-pt: Allow decoding with branch tracing disabled")
Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Use __BYTE_ORDER__

2021-11-07T15:27:38+00:00

Switch from the libc-defined __BYTE_ORDER to the compiler-defined
__BYTE_ORDER__ in order to make endianness detection more robust, like
it was done for libbpf.

Signed-off-by: Ilya Leoshkevich 
Suggested-by: Arnaldo Carvalho de Melo 
Cc: Heiko Carstens 
Cc: Thomas Richter 
Cc: Vasily Gorbik 
Link: https://lore.kernel.org/r/20211104132311.984703-1-iii@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo

Merge remote-tracking branch 'torvalds/master' into perf/core

2021-11-06T18:49:33+00:00

To pick up some tools/perf/ patches that went via tip/perf/core, such
as:

  tools/perf: Add mem_hops field in perf_mem_data_src structure

Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Support itrace d+o option to direct debug log to stdout

2021-10-27T19:21:01+00:00

It can be useful to see debug output in between normal output.

Add support for AUXTRACE_LOG_FLG_USE_STDOUT to Intel PT.

Reviewed-by: Andi Kleen 
Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Link: https://lore.kernel.org/r/20211027080334.365596-7-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Support itrace A option to approximate IPC

2021-10-27T19:20:18+00:00

Normally, for cycle-acccurate mode, IPC values are an exact number of
instructions and cycles. Due to the granularity of timestamps, that happens
only when a CYC packet correlates to the event.

Support the itrace 'A' option, to use instead, the number of cycles
associated with the current timestamp. This provides IPC information for
every change of timestamp, but at the expense of accuracy. Due to the
granularity of timestamps, the actual number of cycles increases even
though the cycles reported does not. The number of instructions is known,
but if IPC is reported, cycles can be too low and so IPC is too high. Note
that inaccuracy decreases as the period of sampling increases i.e. if the
number of cycles is too low by a small amount, that becomes less
significant if the number of cycles is large.

Furthermore, it can be used in conjunction with dlfilter-show-cycles.so
to provide higher granularity cycle information.

Reviewed-by: Andi Kleen 
Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Link: https://lore.kernel.org/r/20211027080334.365596-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo