History log of /linux-6.15/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c (Results 1 – 25 of 93)
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Revision tags: v6.15, v6.15-rc7, v6.15-rc6, v6.15-rc5, v6.15-rc4, v6.15-rc3, v6.15-rc2, v6.15-rc1, v6.14, v6.14-rc7, v6.14-rc6, v6.14-rc5, v6.14-rc4, v6.14-rc3, v6.14-rc2, v6.14-rc1, v6.13, v6.13-rc7, v6.13-rc6, v6.13-rc5, v6.13-rc4, v6.13-rc3, v6.13-rc2, v6.13-rc1, v6.12, v6.12-rc7, v6.12-rc6, v6.12-rc5, v6.12-rc4, v6.12-rc3, v6.12-rc2, v6.12-rc1, v6.11, v6.11-rc7, v6.11-rc6, v6.11-rc5, v6.11-rc4, v6.11-rc3, v6.11-rc2, v6.11-rc1, v6.10, v6.10-rc7, v6.10-rc6, v6.10-rc5, v6.10-rc4, v6.10-rc3, v6.10-rc2, v6.10-rc1, v6.9, v6.9-rc7, v6.9-rc6, v6.9-rc5, v6.9-rc4, v6.9-rc3, v6.9-rc2
# e101a05f 26-Mar-2024 Adrian Hunter <[email protected]>

perf intel-pt: Fix unassigned instruction op (discovered by MemorySanitizer)

MemorySanitizer discovered instances where the instruction op value was
not assigned.:

WARNING: MemorySanitizer: use-o

perf intel-pt: Fix unassigned instruction op (discovered by MemorySanitizer)

MemorySanitizer discovered instances where the instruction op value was
not assigned.:

WARNING: MemorySanitizer: use-of-uninitialized-value
#0 0x5581c00a76b3 in intel_pt_sample_flags tools/perf/util/intel-pt.c:1527:17
Uninitialized value was stored to memory at
#0 0x5581c005ddf8 in intel_pt_walk_insn tools/perf/util/intel-pt-decoder/intel-pt-decoder.c:1256:25

The op value is used to set branch flags for branch instructions
encountered when walking the code, so fix by setting op to
INTEL_PT_OP_OTHER in other cases.

Fixes: 4c761d805bb2d2ea ("perf intel-pt: Fix intel_pt_fup_event() assumptions about setting state type")
Reported-by: Ian Rogers <[email protected]>
Signed-off-by: Adrian Hunter <[email protected]>
Tested-by: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Closes: https://lore.kernel.org/linux-perf-users/[email protected]/
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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Revision tags: v6.9-rc1, v6.8, v6.8-rc7, v6.8-rc6, v6.8-rc5, v6.8-rc4, v6.8-rc3, v6.8-rc2, v6.8-rc1, v6.7, v6.7-rc8, v6.7-rc7, v6.7-rc6, v6.7-rc5, v6.7-rc4, v6.7-rc3, v6.7-rc2, v6.7-rc1, v6.6, v6.6-rc7, v6.6-rc6, v6.6-rc5, v6.6-rc4, v6.6-rc3, v6.6-rc2, v6.6-rc1, v6.5, v6.5-rc7, v6.5-rc6, v6.5-rc5, v6.5-rc4, v6.5-rc3, v6.5-rc2, v6.5-rc1, v6.4, v6.4-rc7, v6.4-rc6, v6.4-rc5, v6.4-rc4, v6.4-rc3, v6.4-rc2, v6.4-rc1, v6.3, v6.3-rc7, v6.3-rc6, v6.3-rc5, v6.3-rc4, v6.3-rc3, v6.3-rc2, v6.3-rc1, v6.2, v6.2-rc8, v6.2-rc7, v6.2-rc6, v6.2-rc5, v6.2-rc4, v6.2-rc3, v6.2-rc2, v6.2-rc1, v6.1, v6.1-rc8, v6.1-rc7
# f7a858bf 25-Nov-2022 Liam Howlett <[email protected]>

tools: Rename __fallthrough to fallthrough

Rename the fallthrough attribute to better align with the kernel
version. Copy the definition from include/linux/compiler_attributes.h
including the #else

tools: Rename __fallthrough to fallthrough

Rename the fallthrough attribute to better align with the kernel
version. Copy the definition from include/linux/compiler_attributes.h
including the #else clause. Adding the #else clause allows the tools
compiler.h header to drop the check for a definition entirely and keeps
both definitions together.

Change any __fallthrough statements to fallthrough anywhere it was used
within perf.

This allows other tools to use the same key word as the kernel.

Committer notes:

Did some missing conversions to:

builtin-list.c

Also included gtk.h before the 'fallthrough' definition in:

tools/perf/ui/gtk/hists.c
tools/perf/ui/gtk/helpline.c
tools/perf/ui/gtk/browser.c

As it is the arg name for a macro in glib.h:

/var/home/acme/git/perf-tools-next/tools/include/linux/compiler-gcc.h:16:55: error: missing binary operator before token "("
16 | # define fallthrough __attribute__((__fallthrough__))
| ^
/usr/include/glib-2.0/glib/gmacros.h:637:28: note: in expansion of macro ‘fallthrough’
637 | #if g_macro__has_attribute(fallthrough)

Reviewed-by: Miguel Ojeda <[email protected]>
Signed-off-by: Liam Howlett <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Tom Rix <[email protected]>
Cc: [email protected] <[email protected]>
Cc: [email protected] <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


# 430635a0 03-Apr-2023 Adrian Hunter <[email protected]>

perf intel-pt: Fix CYC timestamps after standalone CBR

After a standalone CBR (not associated with TSC), update the cycles
reference timestamp and reset the cycle count, so that CYC timestamps
are c

perf intel-pt: Fix CYC timestamps after standalone CBR

After a standalone CBR (not associated with TSC), update the cycles
reference timestamp and reset the cycle count, so that CYC timestamps
are calculated relative to that point with the new frequency.

Fixes: cc33618619cefc6d ("perf tools: Add Intel PT support for decoding CYC packets")
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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Revision tags: v6.1-rc6, v6.1-rc5, v6.1-rc4, v6.1-rc3, v6.1-rc2, v6.1-rc1, v6.0, v6.0-rc7, v6.0-rc6, v6.0-rc5, v6.0-rc4, v6.0-rc3, v6.0-rc2, v6.0-rc1, v5.19, v5.19-rc8, v5.19-rc7, v5.19-rc6, v5.19-rc5, v5.19-rc4, v5.19-rc3, v5.19-rc2, v5.19-rc1, v5.18, v5.18-rc7
# d7015e50 09-May-2022 Adrian Hunter <[email protected]>

perf intel-pt: Add support for emulated ptwrite

ptwrite is an Intel x86 instruction that writes arbitrary values into an
Intel PT trace. It is not supported on all hardware, so provide an
alternativ

perf intel-pt: Add support for emulated ptwrite

ptwrite is an Intel x86 instruction that writes arbitrary values into an
Intel PT trace. It is not supported on all hardware, so provide an
alternative that makes use of TNT packets to convey the payload data.
TNT packets encode Taken/Not-taken conditional branch information, so
taking branches based on the payload value will encode the value into
the TNT packet. Refer to the changes to the documentation file
perf-intel-pt.txt in this patch for an example.

Signed-off-by: Adrian Hunter <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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Revision tags: v5.18-rc6, v5.18-rc5, v5.18-rc4, v5.18-rc3, v5.18-rc2, v5.18-rc1, v5.17, v5.17-rc8, v5.17-rc7, v5.17-rc6, v5.17-rc5, v5.17-rc4, v5.17-rc3, v5.17-rc2
# cf0c98e2 24-Jan-2022 Adrian Hunter <[email protected]>

perf intel-pt: decoder: Add MODE.Exec IFLAG processing

As of Intel SDM (https://www.intel.com/sdm) version 076, there is a new
Intel PT feature called Event Trace which adds a bit to the existing
MO

perf intel-pt: decoder: Add MODE.Exec IFLAG processing

As of Intel SDM (https://www.intel.com/sdm) version 076, there is a new
Intel PT feature called Event Trace which adds a bit to the existing
MODE.Exec packet to record the interrupt flag.

Previously, the MODE.Exec packet did not generate any events, so the
new processing required is practically the same as a new packet.

Signed-off-by: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


# 3733a98b 24-Jan-2022 Adrian Hunter <[email protected]>

perf intel-pt: decoder: Add CFE (Control Flow Event) and EVD (Event Data) processing

As of Intel SDM (https://www.intel.com/sdm) version 076, there is a new
Intel PT feature called Event Trace which

perf intel-pt: decoder: Add CFE (Control Flow Event) and EVD (Event Data) processing

As of Intel SDM (https://www.intel.com/sdm) version 076, there is a new
Intel PT feature called Event Trace which requires 2 new packets CFE
(Control Flow Event) and EVD (Event Data).

Each Event Trace event is represented by a CFE packet that is preceded
by zero or more EVD packets. It may be bound to a following FUP (Flow
Update) packet that provides the IP.

Event Trace exposes details about asynchronous events. The CFE packet
contains a type field to identify one of the following:

1 INTR interrupt, fault, exception, NMI
2 IRET interrupt return
3 SMI system management interrupt
4 RSM resume from system management mode
5 SIPI startup interprocessor interrupt
6 INIT INIT signal
7 VMENTRY VM-Entry
8 VMEXIT VM-Entry
9 VMEXIT_INTR VM-Exit due to interrupt
10 SHUTDOWN Shutdown

For more details, refer to the Intel SDM, Intel Processor Trace chapter.

Add processing to the decoder for the new packets.

Signed-off-by: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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# 68ff3cba 24-Jan-2022 Adrian Hunter <[email protected]>

perf intel-pt: decoder: Factor out clearing of FUP (Flow Update) event variables

Factor out clearing of FUP (Flow Update) event variables, to avoid code duplication.

Committer Notes:

From the Inte

perf intel-pt: decoder: Factor out clearing of FUP (Flow Update) event variables

Factor out clearing of FUP (Flow Update) event variables, to avoid code duplication.

Committer Notes:

From the Intel documentation:

<quote>
Flow Update Packets (FUP): FUPs provide the source IP addresses for
asynchronous events (interrupt and exceptions), as well as other cases
where the source address cannot be determined from the binary.
</quote>

Signed-off-by: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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# 2750af50 24-Jan-2022 Adrian Hunter <[email protected]>

perf intel-pt: pkt-decoder: Add CFE and EVD packets

As of Intel SDM (https://www.intel.com/sdm) version 076, there is a new
Intel PT feature called Event Trace which requires 2 new packets CFE and
E

perf intel-pt: pkt-decoder: Add CFE and EVD packets

As of Intel SDM (https://www.intel.com/sdm) version 076, there is a new
Intel PT feature called Event Trace which requires 2 new packets CFE and
EVD. Add them to the packet decoder and packet decoder test.

Committer notes:

I got the "Intel® 64 and IA-32 architectures software developer’s manual
combined volumes: 1, 2A, 2B, 2C, 2D, 3A, 3B, 3C, 3D, and 4" PDF at:

https://cdrdv2.intel.com/v1/dl/getContent/671200

And these new packets are described in page 3951:

<quote>
32.2.4

Event Trace is a capability that exposes details about the asynchronous
events, when they are generated, and when their corresponding software
event handler completes execution. These include:

o Interrupts, including NMI and SMI, including the interrupt vector when
defined.

o Faults, exceptions including the fault vector.

— Page faults additionally include the page fault address, when in context.

o Event handler returns, including IRET and RSM.

o VM exits and VM entries.¹

— VM exits include the values written to the “exit reason” and “exit qualification” VMCS fields.
INIT and SIPI events.

o TSX aborts, including the abort status returned for the RTM instructions.

o Shutdown.

Additionally, it provides indication of the status of the Interrupt Flag
(IF), to indicate when interrupts are masked.
</quote>

Signed-off-by: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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Revision tags: v5.17-rc1, v5.16, v5.16-rc8, v5.16-rc7, v5.16-rc6, v5.16-rc5
# a882cc94 10-Dec-2021 Adrian Hunter <[email protected]>

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

FUP packets contain IP information, which makes them also an 'instruction'
event in 'hop' mode i.e. the itrace 'q' option. That wasn'

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

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 <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected] # v5.15+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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# a32e6c5d 10-Dec-2021 Adrian Hunter <[email protected]>

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

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:

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

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 <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected] # v5.15+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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# c79ee2b2 10-Dec-2021 Adrian Hunter <[email protected]>

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

An overflow (OVF packet) is treated as an error because it represents a
loss of trace data, but there is no loss of synchronizat

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

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 <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected] # v5.15+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


# 4c761d80 10-Dec-2021 Adrian Hunter <[email protected]>

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

intel_pt_fup_event() assumes it can overwrite the state type if there has
been an FUP event, but this is an unnecessary a

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

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 <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected] # v5.15+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


# ad106a26 10-Dec-2021 Adrian Hunter <[email protected]>

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

When syncing, it may be that branch packet generation is not enabled at
that point, in which case there will not immediatel

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

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 <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected] # v5.15+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


# 057ae59f 10-Dec-2021 Adrian Hunter <[email protected]>

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

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

PGE may be false e

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

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 <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected] # v5.15+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


Revision tags: v5.16-rc4, v5.16-rc3, v5.16-rc2, v5.16-rc1, v5.15
# f2b91386 27-Oct-2021 Adrian Hunter <[email protected]>

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

Normally, for cycle-acccurate mode, IPC values are an exact number of
instructions and cycles. Due to the granularity of timestamps, that ha

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

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 <[email protected]>
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


Revision tags: v5.15-rc7, v5.15-rc6, v5.15-rc5, v5.15-rc4, v5.15-rc3, v5.15-rc2, v5.15-rc1, v5.14, v5.14-rc7, v5.14-rc6, v5.14-rc5, v5.14-rc4, v5.14-rc3, v5.14-rc2, v5.14-rc1
# b4b046ff 01-Jul-2021 Adrian Hunter <[email protected]>

perf intel-pt: Add a config for max loops without consuming a packet

The Intel PT decoder limits the number of unconditional branches (e.g.
jmps) decoded without consuming any trace packets. General

perf intel-pt: Add a config for max loops without consuming a packet

The Intel PT decoder limits the number of unconditional branches (e.g.
jmps) decoded without consuming any trace packets. Generally, a loop
needs a conditional branch which generates a TNT packet, whereas a "ret"
instruction will generate a TIP or TNT packet. So exceeding the limit is
assumed to be a never-ending loop, which can happen if there has been a
decoding error putting the decoder at the wrong place in the code.

Up until now, the limit of 10000 has been enough but some analytic
purposes have been reported to exceed that.

Increase the limit to 100000, and make it configurable via perf config
intel-pt.max-loops. Also amend the "Never-ending loop" message to
mention the configuration entry.

Signed-off-by: Adrian Hunter <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


Revision tags: v5.13, v5.13-rc7, v5.13-rc6, v5.13-rc5, v5.13-rc4, v5.13-rc3, v5.13-rc2, v5.13-rc1
# fa8f949d 30-Apr-2021 Adrian Hunter <[email protected]>

perf intel-pt: Add VM Time Correlation to decoder

VM Time Correlation means determining if each TSC packet belongs to a VM
Guest or the Host. When the trace is "in context" that is indicated by
the

perf intel-pt: Add VM Time Correlation to decoder

VM Time Correlation means determining if each TSC packet belongs to a VM
Guest or the Host. When the trace is "in context" that is indicated by
the NR flag in the PIP packet. However, when tracing kernel-only,
userspace only, or using address filters, the trace can be "out of context"
in which case timing packets are produced but not PIP packets.

Nevertheless, it is very unlikely the VM Guest timestamps will be in
the same range as the Host timestamps. Host time ranges are established
by a starting side-band event timestamp, and subsequently by the buffer
timestamp, written when the buffer is copied to the perf.data file.

This patch supports updating the VM Guest timestamp packets, assuming an
unchanging (during perf record) VMX TSC Offset and no VMX TSC scaling.

Furthermore, it is possible to determine what the VMX TSC Offset is,
although not necessarily at the start. The dry-run option lets that
information be determined so that the user can pass it to a subsequent
run. For more detail, refer to the example in the Intel PT documentation
in a subsequent patch.

VM Time Correlation is also performed on the TSC value in PEBs-via-PT
records.

Signed-off-by: Adrian Hunter <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


# 31c7e27d 30-Apr-2021 Adrian Hunter <[email protected]>

perf intel-pt: Better 7-byte timestamp wraparound logic

A timestamp should not go backwards. If it does it is assumed that the
7-byte TSC packet value has wrapped. Improve that logic so that it wil

perf intel-pt: Better 7-byte timestamp wraparound logic

A timestamp should not go backwards. If it does it is assumed that the
7-byte TSC packet value has wrapped. Improve that logic so that it will
not allow the timestamp to go past the buffer timestamp (which is recorded
when the buffer is copied out)

Signed-off-by: Adrian Hunter <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


# 5ac35d77 30-Apr-2021 Adrian Hunter <[email protected]>

perf intel-pt: Pass the first timestamp to the decoder

VM Time Correlation will use time ranges to determine whether a TSC packet
belongs to the Host or Guest. To start, the first non-zero timestamp

perf intel-pt: Pass the first timestamp to the decoder

VM Time Correlation will use time ranges to determine whether a TSC packet
belongs to the Host or Guest. To start, the first non-zero timestamp is
needed. Pass that to the decoder.

Signed-off-by: Adrian Hunter <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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# 0fc9d338 30-Apr-2021 Adrian Hunter <[email protected]>

perf intel-pt: Add a tree for VMCS information

Even when VMX TSC Offset is not changing (during perf record), different
virtual machines can have different TSC Offsets. There is a Virtual Machine
Co

perf intel-pt: Add a tree for VMCS information

Even when VMX TSC Offset is not changing (during perf record), different
virtual machines can have different TSC Offsets. There is a Virtual Machine
Control Structure (VMCS) for each virtual CPU, the address of which is
reported to Intel PT in the VMCS packet. We do not know which VMCS belongs
to which virtual machine, so use a tree to keep track of VMCS information.
Then the decoder will be able to use the current VMCS value to look up the
current TSC Offset.

Signed-off-by: Adrian Hunter <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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# 335358cc 30-Apr-2021 Adrian Hunter <[email protected]>

perf intel-pt: Let overlap detection handle VM timestamps

Intel PT timestamps are affected by virtualization. While TSC packets can
still be considered to be unique, the TSC values need not be in or

perf intel-pt: Let overlap detection handle VM timestamps

Intel PT timestamps are affected by virtualization. While TSC packets can
still be considered to be unique, the TSC values need not be in order any
more. Adjust the algorithm accordingly.

Signed-off-by: Adrian Hunter <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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# cb798783 19-May-2021 Adrian Hunter <[email protected]>

perf intel-pt: Fix transaction abort handling

When adding support for power events, some handling of FUP packets was
unified. That resulted in breaking reporting of TSX aborts, by not
considering th

perf intel-pt: Fix transaction abort handling

When adding support for power events, some handling of FUP packets was
unified. That resulted in breaking reporting of TSX aborts, by not
considering the associated TIP packet. Fix that.

Example:

A machine that supports TSX is required. It will have flag "rtm". Kernel
parameter tsx=on may be required.

# for w in `cat /proc/cpuinfo | grep -m1 flags `;do echo $w | grep rtm ; done
rtm

Test program:

#include <stdio.h>
#include <immintrin.h>

int main()
{
int x = 0;

if (_xbegin() == _XBEGIN_STARTED) {
x = 1;
_xabort(1);
} else {
printf("x = %d\n", x);
}
return 0;
}

Compile with -mrtm i.e.

gcc -Wall -Wextra -mrtm xabort.c -o xabort

Record:

perf record -e intel_pt/cyc/u --filter 'filter main @ ./xabort' ./xabort

Before:

# perf script --itrace=be -F+flags,+addr,-period,-event --ns
xabort 1478 [007] 92161.431348552: tr strt 0 [unknown] ([unknown]) => 400b6d main+0x0 (/root/xabort)
xabort 1478 [007] 92161.431348624: jmp 400b96 main+0x29 (/root/xabort) => 400bae main+0x41 (/root/xabort)
xabort 1478 [007] 92161.431348624: return 400bb4 main+0x47 (/root/xabort) => 400b87 main+0x1a (/root/xabort)
xabort 1478 [007] 92161.431348637: jcc 400b8a main+0x1d (/root/xabort) => 400b98 main+0x2b (/root/xabort)
xabort 1478 [007] 92161.431348644: tr end call 400ba9 main+0x3c (/root/xabort) => 40f690 printf+0x0 (/root/xabort)
xabort 1478 [007] 92161.431360859: tr strt 0 [unknown] ([unknown]) => 400bae main+0x41 (/root/xabort)
xabort 1478 [007] 92161.431360882: tr end return 400bb4 main+0x47 (/root/xabort) => 401139 __libc_start_main+0x309 (/root/xabort)

After:

# perf script --itrace=be -F+flags,+addr,-period,-event --ns
xabort 1478 [007] 92161.431348552: tr strt 0 [unknown] ([unknown]) => 400b6d main+0x0 (/root/xabort)
xabort 1478 [007] 92161.431348624: tx abrt 400b93 main+0x26 (/root/xabort) => 400b87 main+0x1a (/root/xabort)
xabort 1478 [007] 92161.431348637: jcc 400b8a main+0x1d (/root/xabort) => 400b98 main+0x2b (/root/xabort)
xabort 1478 [007] 92161.431348644: tr end call 400ba9 main+0x3c (/root/xabort) => 40f690 printf+0x0 (/root/xabort)
xabort 1478 [007] 92161.431360859: tr strt 0 [unknown] ([unknown]) => 400bae main+0x41 (/root/xabort)
xabort 1478 [007] 92161.431360882: tr end return 400bb4 main+0x47 (/root/xabort) => 401139 __libc_start_main+0x309 (/root/xabort)

Fixes: a472e65fc490a ("perf intel-pt: Add decoder support for ptwrite and power event packets")
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected]
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


Revision tags: v5.12, v5.12-rc8, v5.12-rc7, v5.12-rc6, v5.12-rc5, v5.12-rc4, v5.12-rc3, v5.12-rc2, v5.12-rc1, v5.12-rc1-dontuse
# 80a03886 18-Feb-2021 Adrian Hunter <[email protected]>

perf intel-pt: Amend decoder to track the NR flag

The PIP packet NR (non-root) flag indicates whether or not a virtual
machine is being traced (NR=1 => VM). Add support for tracking its value.

In p

perf intel-pt: Amend decoder to track the NR flag

The PIP packet NR (non-root) flag indicates whether or not a virtual
machine is being traced (NR=1 => VM). Add support for tracking its value.

In particular note that the PIP packet (outside of PSB+) will be
associated with a TIP packet from which address the NR value takes
effect. At that point, there is a branch from_ip, to_ip with
corresponding from_nr and to_nr.

In the event of VM-Entry failure, there should still PIP and TIP packets
that can be followed in the same way.

Also note that this assumes that a host VMM is not employing VMX controls
that affect Intel PT, e.g. to hide the host from a guest using Intel PT.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Andi Kleen <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


# 90af7555 18-Feb-2021 Adrian Hunter <[email protected]>

perf intel-pt: Retain the last PIP packet payload as is

Retain the PIP packet payload as is, instead of just the CR3, because it
contains also the VMX NR flag which is needed to track VM-Entry.

Sig

perf intel-pt: Retain the last PIP packet payload as is

Retain the PIP packet payload as is, instead of just the CR3, because it
contains also the VMX NR flag which is needed to track VM-Entry.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Andi Kleen <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...


Revision tags: v5.11, v5.11-rc7
# c840cbfe 05-Feb-2021 Adrian Hunter <[email protected]>

perf intel-pt: Add PSB events

Emitting a PSB+ can cause a CPU a slight delay. When doing timing analysis
of code with Intel PT, it is useful to know if a timing bubble was caused
by Intel PT or not.

perf intel-pt: Add PSB events

Emitting a PSB+ can cause a CPU a slight delay. When doing timing analysis
of code with Intel PT, it is useful to know if a timing bubble was caused
by Intel PT or not. Add reporting of PSB events via perf script. PSB
events are printed with the existing itrace 'p' option which also prints
power and frequency changes. The PSB event contains the trace offset at
which the PSB occurs, to allow easy reference back to the PSB+ packets.

The PSB event timestamp is always the timestamp from the PSB+ TSC
packet, and the ip is always the address from the PSB+ FUP packet.

The code changes are non-trivial because the decoder must walk to the
PSB+ FUP address before outputting the PSB event.

Example:

$ perf record -e intel_pt/cyc,psb_period=0/u uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.046 MB perf.data ]
$ perf script --itrace=p --ns
perf 17981 [006] 25617.510820383: psb: psb offs: 0 0 [unknown] ([unknown])
perf 17981 [006] 25617.510820383: cbr: cbr: 42 freq: 4219 MHz (156%) 0 [unknown] ([unknown])
uname 17981 [006] 25617.510889753: psb: psb offs: 0xb50 7f78c12a212e __GI___tunables_init+0xee (/usr/lib/x86_64-linux-gnu/ld-2.31.so)
uname 17981 [006] 25617.510899162: psb: psb offs: 0x12d0 7f78c128af1c dl_main+0x93c (/usr/lib/x86_64-linux-gnu/ld-2.31.so)
uname 17981 [006] 25617.510939242: psb: psb offs: 0x1a50 7f78c128eefc _dl_map_object_from_fd+0x13c (/usr/lib/x86_64-linux-gnu/ld-2.31.so)
uname 17981 [006] 25617.510981274: psb: psb offs: 0x21c8 7f78c1296307 _dl_relocate_object+0x927 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)
uname 17981 [006] 25617.510993034: psb: psb offs: 0x2948 7f78c12940e4 _dl_lookup_symbol_x+0x14 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)
uname 17981 [006] 25617.511003871: psb: psb offs: 0x30c8 7f78c12937b3 do_lookup_x+0x2f3 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)
uname 17981 [006] 25617.511019854: psb: psb offs: 0x3850 7f78c1295eed _dl_relocate_object+0x50d (/usr/lib/x86_64-linux-gnu/ld-2.31.so)
uname 17981 [006] 25617.511029015: psb: psb offs: 0x4390 7f78c12a855a strcmp+0xf6a (/usr/lib/x86_64-linux-gnu/ld-2.31.so)
uname 17981 [006] 25617.511064876: psb: psb offs: 0x4b10 0 [unknown] ([unknown])
uname 17981 [006] 25617.511080762: psb: psb offs: 0x5290 7f78c11db53d _dl_addr+0x13d (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511086035: psb: psb offs: 0x5a08 7f78c11db538 _dl_addr+0x138 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511091381: psb: psb offs: 0x6190 7f78c11db534 _dl_addr+0x134 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511096681: psb: psb offs: 0x6910 7f78c11db4c3 _dl_addr+0xc3 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511119520: psb: psb offs: 0x7090 7f78c10ada5e _nl_intern_locale_data+0x12e (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511126584: psb: psb offs: 0x7818 7f78c10ada50 _nl_intern_locale_data+0x120 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511132775: psb: psb offs: 0x8358 7f78c10c20c0 getenv+0xa0 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511134598: psb: psb offs: 0x8ad0 7f78c10ada09 _nl_intern_locale_data+0xd9 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511135685: psb: psb offs: 0x9258 7f78c10ada50 _nl_intern_locale_data+0x120 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511138322: psb: psb offs: 0x99d0 7f78c11fffd9 __strncmp_avx2+0x39 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
uname 17981 [006] 25617.511158907: psb: psb offs: 0xa150 0 [unknown] ([unknown])

Signed-off-by: Adrian Hunter <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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