commit 91d29b288aed3406caf7c454bf2b898c96cfd177 upstream.
timestamp_insn_cnt is used to estimate the timestamp based on the number of
instructions since the last known timestamp.
If the estimate is not accurate enough decoding might not be correctly
synchronized with side-band events causing more trace errors.
However there are always timestamps following an overflow, so the
estimate is not needed and can indeed result in more errors.
Suppress the estimate by setting timestamp_insn_cnt to zero.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1520431349-30689-5-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1c196a6c771c47a2faa63d38d913e03284f73a16 upstream.
When a TIP packet is expected but there is a different packet, it is an
error. However the unexpected packet might be something important like a
TSC packet, so after the error, it is necessary to continue from there,
rather than the next packet. That is achieved by setting pkt_step to
zero.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1520431349-30689-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 117db4b27bf08dba412faf3924ba55fe970c57b8 upstream.
Overlap detection was not not updating the buffer's 'consecutive' flag.
Marking buffers consecutive has the advantage that decoding begins from
the start of the buffer instead of the first PSB. Fix overlap detection
to identify consecutive buffers correctly.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1520431349-30689-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f952eaceb089b691eba7c4e13686e742a8f26bf5 upstream.
Intel PT uses IP compression based on the last IP. For decoding purposes,
'last IP' is not updated when a branch target has been suppressed, which is
indicated by IPBytes == 0. IPBytes is stored in the packet 'count', so
ensure never to set 'last_ip' when packet 'count' is zero.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-7-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 622b7a47b843c78626f40c1d1aeef8483383fba2 upstream.
The decoder will try to use branch packets to find an IP to start decoding
or to recover from errors. Currently the FUP packet is used only in the
case of an overflow, however there is no reason for that to be a special
case. So just use FUP always when scanning for an IP.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-8-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ee14ac0ef6827cd6f9a572cc83dd0191ea17812c upstream.
Intel PT uses IP compression based on the last IP. For decoding
purposes, 'last IP' is considered to be reset to zero whenever there is
a synchronization packet (PSB). The decoder wasn't doing that, and was
treating the zero value to mean that there was no last IP, whereas
compression can be done against the zero value. Fix by setting last_ip
to zero when a PSB is received and keep track of have_last_ip.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e1717e0485af4f47fc4da1e979ac817f9ad61b0f upstream.
The June 2015 Intel SDM introduced IP Compression types 4 and 6. Refer
to section 36.4.2.2 Target IP (TIP) Packet - IP Compression.
Existing Intel PT packet decoder did not support type 4, and got type 6
wrong. Because type 3 and type 4 have the same number of bytes, the
packet 'count' has been changed from being the number of ip bytes to
being the type code. That allows the Intel PT decoder to correctly
decide whether to sign-extend or use the last ip. However that also
meant the code had to be adjusted in a number of places.
Currently hardware is not using the new compression types, so this fix
has no effect on existing hardware.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1469005206-3049-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6a558f12dbe85437acbdec5e149ea07b5554eced upstream.
Sometimes a FUP packet is associated with a TSX transaction and a flag is
set to indicate that. Ensure that flag is cleared on any error condition
because at that point the decoder can no longer assume it is correct.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-9-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ad7167a8cd174ba7d8c0d0ed8d8410521206d104 upstream.
A value of zero is used to indicate that there is no IP. Ensure the
value is zero when the state is INTEL_PT_STATE_NO_IP.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-5-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 12b7080609097753fd8198cc1daf589be3ec1cca upstream.
The return compression stack must be cleared whenever there is a PSB. Fix
one case where that was not happening.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3f04d98e972b59706bd43d6cc75efac91f8fba50 upstream.
The decoder uses its current timestamp in samples. Usually that is a
timestamp that has already passed, but in some cases it is a timestamp
for a branch that the decoder is walking towards, and consequently
hasn't reached. Improve that situation by using the pkt_state to
determine when to use the current or previous timestamp.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 22c06892332d8916115525145b78e606e9cc6492 upstream.
Move decoder error setting into one condition.
Cc'ed to stable because later fixes depend on it.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7ea6856d6f5629d742edc23b8b76e6263371ef45 upstream.
To address new warnings emmited by gcc 7, e.g.::
CC /tmp/build/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.o
CC /tmp/build/perf/tests/parse-events.o
util/intel-pt-decoder/intel-pt-pkt-decoder.c: In function 'intel_pt_pkt_desc':
util/intel-pt-decoder/intel-pt-pkt-decoder.c:499:6: error: this statement may fall through [-Werror=implicit-fallthrough=]
if (!(packet->count))
^
util/intel-pt-decoder/intel-pt-pkt-decoder.c:501:2: note: here
case INTEL_PT_CYC:
^~~~
CC /tmp/build/perf/util/intel-pt-decoder/intel-pt-decoder.o
cc1: all warnings being treated as errors
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-mf0hw789pu9x855us5l32c83@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3bccbe20f6d188ce7b00326e776b745cfd35b10a upstream.
The MTC packet provides a 8-bit slice of CTC which is related to TSC by
the TMA packet, however the TMA packet only provides the lower 16 bits
of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
packet by copying the missing bits from the current MTC assuming the
least difference between the two, and that the current MTC comes after
last_mtc.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1475062896-22274-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 51ee6481fa8e879cc942bcc1b0af713e158b7a98 upstream.
In cycle-accurate mode, timestamps can be calculated from CYC packets.
The decoder also estimates timestamps based on the number of
instructions since the last timestamp. For that to work in
cycle-accurate mode, the instruction count needs to be reset to zero
when a timestamp is calculated from a CYC packet, but that wasn't
happening, so fix it.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1475062896-22274-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
TSC packets contain only 7 bytes of TSC. The 8th byte is assumed to
change so infrequently that its value can be inferred. However the
logic must cater for a 7 byte wraparound, which it does by adding 1 to
the top byte.
The existing code was doing that with a while loop even though the
addition should only need to be done once. That logic won't work (will
loop forever) if TSC wraps around at the 8th byte. Theoretically that
would take at least 10 years, unless something else went wrong.
And what else could go wrong. Well, if the chunks of trace data are
processed out of order, it will make it look like the 7-byte TSC has
gone backwards (i.e. wrapped). If that happens 256 times then stuck in
the while loop it will be.
Fix that by getting rid of the unnecessary while loop.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1443186956-18718-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A TRACESTOP packet is produced when an Intel PT trace enters a defined
region of the address space at which point the tracing stops.
This patch just adds decoder support.
Support for specifying TRACESTOP regions is left until later.
For details refer to the June 2015 or later Intel 64 and IA-32
Architectures SDM Chapter 36 Intel Processor Trace.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1437150840-31811-25-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
CYC packets provide even finer grain timestamp information than MTC and
TSC packets. A CYC packet contains the number of CPU cycles since the
last CYC packet.
This patch just adds decoder support. The CPU frequency can be related
to TSC using the Maximum Non-Turbo Ratio in combination with the CBR
(core-to-bus ratio) packet. However more accuracy is achieved by simply
interpolating the number of cycles between other timing packets like MTC
or TSC. This patch takes the latter approach.
Support for a default value and validation of values is provided by a
later patch. Also documentation is updated in a separate patch.
For details refer to the June 2015 or later Intel 64 and IA-32
Architectures SDM Chapter 36 Intel Processor Trace.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1437150840-31811-23-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
MTC packets provide finer grain timestamp information than TSC packets.
MTC packets record time using the hardware crystal clock (CTC) which is
related to TSC packets using a TMA packet.
This patch just adds decoder support.
Support for a default value and validation of values is provided by a
later patch. Also documentation is updated in a separate patch.
For details refer to the June 2015 or later Intel 64 and IA-32
Architectures SDM Chapter 36 Intel Processor Trace.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1437150840-31811-21-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
New features have been added to Intel PT which include a number of new
packet definitions.
This patch adds packet definitions for new packets: TMA, MTC, CYC, VMCS,
TRACESTOP and MNT. Also another bit in PIP is defined.
This patch only adds support for the definitions. Later patches add
support for decoding TMA, MTC, CYC and TRACESTOP which is where those
packets are explained.
VMCS and the newly defined bit in PIP are used with virtualization which
is not supported yet. MNT is a maintenance packet which the decoder
should ignore.
For details, refer to the June 2015 or later Intel 64 and IA-32
Architectures SDM Chapter 36 Intel Processor Trace.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1437150840-31811-19-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The period on synthesized 'instructions' samples was being set to a
fixed value, whereas the correct value is the number of instructions
since the last sample, which is a value that the decoder can provide.
So do it that way.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1437150840-31811-14-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add support for decoding an Intel Processor Trace.
Intel PT trace data must be 'decoded' which involves walking the object
code and matching the trace data packets.
The decoder requests a buffer of binary data via a get_trace()
call-back, which it decodes using instruction information which it gets
via another call-back walk_insn().
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1437150840-31811-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
