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Commit Graph

21 Commits

Author SHA1 Message Date
Kan Liang
fc7ce9c74c perf/core, x86: Add PERF_SAMPLE_PHYS_ADDR
For understanding how the workload maps to memory channels and hardware
behavior, it's very important to collect address maps with physical
addresses. For example, 3D XPoint access can only be found by filtering
the physical address.

Add a new sample type for physical address.

perf already has a facility to collect data virtual address. This patch
introduces a function to convert the virtual address to physical address.
The function is quite generic and can be extended to any architecture as
long as a virtual address is provided.

 - For kernel direct mapping addresses, virt_to_phys is used to convert
   the virtual addresses to physical address.

 - For user virtual addresses, __get_user_pages_fast is used to walk the
   pages tables for user physical address.

 - This does not work for vmalloc addresses right now. These are not
   resolved, but code to do that could be added.

The new sample type requires collecting the virtual address. The
virtual address will not be output unless SAMPLE_ADDR is applied.

For security, the physical address can only be exposed to root or
privileged user.

Tested-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: mpe@ellerman.id.au
Link: http://lkml.kernel.org/r/1503967969-48278-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 15:09:25 +02:00
Andi Kleen
6ae5fa61d2 perf/x86: Fix data source decoding for Skylake
Skylake changed the encoding of the PEBS data source field.
Some combinations are not available anymore, but some new cases
e.g. for L4 cache hit are added.

Fix up the conversion table for Skylake, similar as had been done
for Nehalem.

On Skylake server the encoding for L4 actually means persistent
memory. Handle this case too.

To properly describe it in the abstracted perf format I had to add
some new fields. Since a hit can have only one level add a new
field that is an enumeration, not a bit field to describe
the level. It can describe any level. Some numbers are also
used to describe PMEM and LFB.

Also add a new generic remote flag that can be combined with
the generic level to signify a remote cache.

And there is an extension field for the snoop indication to handle
the Forward state.

I didn't add a generic flag for hops because it's not needed
for Skylake.

I changed the existing encodings for older CPUs to also fill in the
new level and remote fields.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: jolsa@kernel.org
Link: http://lkml.kernel.org/r/20170816222156.19953-3-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-25 11:04:17 +02:00
Andi Kleen
9529835514 perf/x86: Move Nehalem PEBS code to flag
Minor cleanup: use an explicit x86_pmu flag to handle the
missing Lock / TLB information on Nehalem, instead of always
checking the model number for each PEBS sample.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: jolsa@kernel.org
Link: http://lkml.kernel.org/r/20170816222156.19953-2-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-25 11:04:16 +02:00
Jiri Olsa
df6c3db8d3 perf/x86/intel: Add proper condition to run sched_task callbacks
We have 2 functions using the same sched_task callback:

  - PEBS drain for free running counters
  - LBR save/store

Both of them are called from intel_pmu_sched_task() and
either of them can be unwillingly triggered when the
other one is configured to run.

Let's say there's PEBS drain configured in sched_task
callback for the event, but in the callback itself
(intel_pmu_sched_task()) we will also run the code for
LBR save/restore, which we did not ask for, but the
code in intel_pmu_sched_task() does not check for that.

This can lead to extra cycles in some perf monitoring,
like when we monitor PEBS event without LBR data.

  # perf record --no-timestamp -c 10000 -e cycles:p ./perf bench sched pipe -l 1000000

  (We need PEBS, non freq/non timestamp event to enable
   the sched_task callback)

The perf stat of cycles and msr:write_msr for above
command before the change:
  ...
  Performance counter stats for './perf record --no-timestamp -c 10000 -e cycles:p \
                                 ./perf bench sched pipe -l 1000000' (5 runs):

    18,519,557,441      cycles:k
        91,195,527      msr:write_msr

      29.334476406 seconds time elapsed

And after the change:
  ...
  Performance counter stats for './perf record --no-timestamp -c 10000 -e cycles:p \
                                 ./perf bench sched pipe -l 1000000' (5 runs):

    18,704,973,540      cycles:k
        27,184,720      msr:write_msr

      16.977875900 seconds time elapsed

There's no affect on cycles:k because the sched_task happens
with events switched off, however the msr:write_msr tracepoint
counter together with almost 50% of time speedup show the
improvement.

Monitoring LBR event and having extra PEBS drain processing
in sched_task callback showed just a little speedup, because
the drain function does not do much extra work in case there
is no PEBS data.

Adding conditions to recognize the configured work that needs
to be done in the x86_pmu's sched_task callback.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170719075247.GA27506@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-21 09:58:39 +02:00
Jiri Olsa
dc853e26f7 perf/x86/intel: Fix debug_store reset field for freq events
There's a bug in PEBs event enabling code, that prevents PEBS
freq events to work properly after non freq PEBS event was run.

freq events - perf_event_attr::freq set
              -F <freq> option of perf record

PEBS events - perf_event_attr::precise_ip > 0
              default for perf record

Like in following example with CPU 0 busy, we expect ~10000 samples
for following perf tool run:

  # perf record -F 10000 -C 0 sleep 1
  [ perf record: Woken up 2 times to write data ]
  [ perf record: Captured and wrote 0.640 MB perf.data (10031 samples) ]

Everything's fine, but once we run non freq PEBS event like:

  # perf record -c 10000 -C 0 sleep 1
  [ perf record: Woken up 4 times to write data ]
  [ perf record: Captured and wrote 1.053 MB perf.data (20061 samples) ]

the freq events start to fail like this:

  # perf record -F 10000 -C 0 sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.185 MB perf.data (40 samples) ]

The issue is in non freq PEBs event initialization of debug_store reset
field, which value is used to auto-reload the counter value after PEBS
event drain. This value is not being used for PEBS freq events, but once
we run non freq event it stays in debug_store data and screws the
sample_freq counting for PEBS freq events.

Setting the reset field to 0 for freq events.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170714163551.19459-1-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 14:13:41 +02:00
Kan Liang
dd0b06b551 perf/x86/intel: Add Goldmont Plus CPU PMU support
Add perf core PMU support for Intel Goldmont Plus CPU cores:

 - The init code is based on Goldmont.
 - There is a new cache event list, based on the Goldmont cache event
   list.
 - All four general-purpose performance counters support PEBS.
 - The first general-purpose performance counter is for reduced skid
   PEBS mechanism. Using :ppp to indicate the event which want to do
   reduced skid PEBS.
 - Goldmont Plus has 4-wide pipeline for Topdown

Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Link: http://lkml.kernel.org/r/20170712134423.17766-1-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 14:13:40 +02:00
Kan Liang
fd583ad156 perf/x86: Fix spurious NMI with PEBS Load Latency event
Spurious NMIs will be observed with the following command:

  while :; do
    perf record -bae "cpu/umask=0x01,event=0xcd,ldlat=0x80/pp"
                  -e "cpu/umask=0x03,event=0x0/"
                  -e "cpu/umask=0x02,event=0x0/"
                  -e cycles,branches,cache-misses
                  -e cache-references -- sleep 10
  done

The bug was introduced by commit:

  8077eca079 ("perf/x86/pebs: Add workaround for broken OVFL status on HSW+")

That commit clears the status bits for the counters used for PEBS
events, by masking the whole 64 bits pebs_enabled. However, only the
low 32 bits of both status and pebs_enabled are reserved for PEBS-able
counters.

For status bits 32-34 are fixed counter overflow bits. For
pebs_enabled bits 32-34 are for PEBS Load Latency.

In the test case, the PEBS Load Latency event and fixed counter event
could overflow at the same time. The fixed counter overflow bit will
be cleared by mistake. Once it is cleared, the fixed counter overflow
never be processed, which finally trigger spurious NMI.

Correct the PEBS enabled mask by ignoring the non-PEBS bits.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 8077eca079 ("perf/x86/pebs: Add workaround for broken OVFL status on HSW+")
Link: http://lkml.kernel.org/r/1491333246-3965-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:31:39 +02:00
Jiri Olsa
475113d937 perf/x86/intel: Account interrupts for PEBS errors
It's possible to set up PEBS events to get only errors and not
any data, like on SNB-X (model 45) and IVB-EP (model 62)
via 2 perf commands running simultaneously:

    taskset -c 1 ./perf record -c 4 -e branches:pp -j any -C 10

This leads to a soft lock up, because the error path of the
intel_pmu_drain_pebs_nhm() does not account event->hw.interrupt
for error PEBS interrupts, so in case you're getting ONLY
errors you don't have a way to stop the event when it's over
the max_samples_per_tick limit:

  NMI watchdog: BUG: soft lockup - CPU#22 stuck for 22s! [perf_fuzzer:5816]
  ...
  RIP: 0010:[<ffffffff81159232>]  [<ffffffff81159232>] smp_call_function_single+0xe2/0x140
  ...
  Call Trace:
   ? trace_hardirqs_on_caller+0xf5/0x1b0
   ? perf_cgroup_attach+0x70/0x70
   perf_install_in_context+0x199/0x1b0
   ? ctx_resched+0x90/0x90
   SYSC_perf_event_open+0x641/0xf90
   SyS_perf_event_open+0x9/0x10
   do_syscall_64+0x6c/0x1f0
   entry_SYSCALL64_slow_path+0x25/0x25

Add perf_event_account_interrupt() which does the interrupt
and frequency checks and call it from intel_pmu_drain_pebs_nhm()'s
error path.

We keep the pending_kill and pending_wakeup logic only in the
__perf_event_overflow() path, because they make sense only if
there's any data to deliver.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vince@deater.net>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1482931866-6018-2-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:06:49 +01:00
Peter Zijlstra
b8000586c9 perf/x86/intel: Cure bogus unwind from PEBS entries
Vince Weaver reported that perf_fuzzer + KASAN detects that PEBS event
unwinds sometimes do 'weird' things. In particular, we seemed to be
ending up unwinding from random places on the NMI stack.

While it was somewhat expected that the event record BP,SP would not
match the interrupt BP,SP in that the interrupt is strictly later than
the record event, it was overlooked that it could be on an already
overwritten stack.

Therefore, don't copy the recorded BP,SP over the interrupted BP,SP
when we need stack unwinds.

Note that its still possible the unwind doesn't full match the actual
event, as its entirely possible to have done an (I)RET between record
and interrupt, but on average it should still point in the general
direction of where the event came from. Also, it's the best we can do,
considering.

The particular scenario that triggered the bogus NMI stack unwind was
a PEBS event with very short period, upon enabling the event at the
tail of the PMI handler (FREEZE_ON_PMI is not used), it instantly
triggers a record (while still on the NMI stack) which in turn
triggers the next PMI. This then causes back-to-back NMIs and we'll
try and unwind the stack-frame from the last NMI, which obviously is
now overwritten by our own.

Analyzed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davej@codemonkey.org.uk <davej@codemonkey.org.uk>
Cc: dvyukov@google.com <dvyukov@google.com>
Cc: stable@vger.kernel.org
Fixes: ca037701a0 ("perf, x86: Add PEBS infrastructure")
Link: http://lkml.kernel.org/r/20161117171731.GV3157@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:36:58 +01:00
Ingo Molnar
5006921837 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-10 11:17:54 +02:00
Peter Zijlstra
8ef9b8455a perf/x86/intel: Fix PEBSv3 record drain
Alexander hit the WARN_ON_ONCE(!event) on his Skylake while running
the perf fuzzer.

This means the PEBSv3 record included a status bit for an inactive
event, something that _should_ not happen.

Move the code that filters the status bits against our known PEBS
events up a spot to guarantee we only deal with events we know about.

Further add "continue" statements to the WARN_ON_ONCE()s such that
we'll not die nor generate silly events in case we ever do hit them
again.

Reported-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vince@deater.net>
Cc: stable@vger.kernel.org
Fixes: a3d86542de ("perf/x86/intel/pebs: Add PEBSv3 decoding")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-10 11:15:39 +02:00
Jiri Olsa
b6a32f023f perf/x86: Fix PEBS threshold initialization
Latest PEBS rework change could skip initialization
of the ds->pebs_interrupt_threshold for single event
PEBS threshold events.

Make sure the PEBS threshold gets always initialized.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 09e61b4f78 ("perf/x86/intel: Rework the large PEBS setup code")
Link: http://lkml.kernel.org/r/1471511392-29875-1-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 11:58:02 +02:00
Peter Zijlstra
68f7082ffb perf/x86: Ensure perf_sched_cb_{inc,dec}() is only called from pmu::{add,del}()
Currently perf_sched_cb_{inc,dec}() are called from
pmu::{start,stop}(), which has the problem that this can happen from
NMI context, this is making it hard to optimize perf_pmu_sched_task().

Furthermore, we really only need this accounting on pmu::{add,del}(),
so doing it from pmu::{start,stop}() is doing more work than we really
need.

Introduce x86_pmu::{add,del}() and wire up the LBR and PEBS.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 13:13:24 +02:00
Peter Zijlstra
09e61b4f78 perf/x86/intel: Rework the large PEBS setup code
In order to allow optimizing perf_pmu_sched_task() we must ensure
perf_sched_cb_{inc,dec}() are no longer called from NMI context; this
means that pmu::{start,stop}() can no longer use them.

Prepare for this by reworking the whole large PEBS setup code.

The current code relied on the cpuc->pebs_enabled state, however since
that reflects the current active state as per pmu::{start,stop}() we
can no longer rely on this.

Introduce two counters: cpuc->n_pebs and cpuc->n_large_pebs which
count the total number of PEBS events and the number of PEBS events
that have FREERUNNING set, resp.. With this we can tell if the current
setup requires a single record interrupt threshold or can use a larger
buffer.

This also improves the code in that it re-enables the large threshold
once the PEBS event that required single record gets removed.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 13:13:24 +02:00
Kan Liang
8b92c3a78d perf/x86/intel: Add Goldmont CPU support
Add perf core PMU support for Intel Goldmont CPU cores:

 - The init code is based on Silvermont.

 - There is a new cache event list, based on the Silvermont cache event list.

 - Goldmont has 32 LBR entries. It also uses new LBRv6 format, which
   report the cycle information using upper 16-bit of the LBR_TO.

 - It's recommended to use CPU_CLK_UNHALTED.CORE_P + NPEBS for precise cycles.

For details, please refer to the latest SDM058:

 http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-vol-3b-part-2-manual.pdf

Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1460706167-45320-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23 14:12:27 +02:00
Peter Zijlstra
e8d8a90fc5 perf/x86/BTS: Fix RCU usage
This splat reminds us:

[ 8166.045595] [ INFO: suspicious RCU usage. ]

[ 8166.168972]  [<ffffffff81127837>] lockdep_rcu_suspicious+0xe7/0x120
[ 8166.175966]  [<ffffffff811e0bae>] perf_callchain+0x23e/0x250
[ 8166.182280]  [<ffffffff811dda3d>] perf_prepare_sample+0x27d/0x350
[ 8166.189082]  [<ffffffff8100f503>] intel_pmu_drain_bts_buffer+0x133/0x200

... that as the core code does, one should hold rcu_read_lock() over that
entire BTS event-output generation sequence as well.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:08:17 +01:00
Andi Kleen
e17dc65328 perf/x86/intel: Fix PEBS data source interpretation on Nehalem/Westmere
Jiri reported some time ago that some entries in the PEBS data source table
in perf do not agree with the SDM. We investigated and the bits
changed for Sandy Bridge, but the SDM was not updated.

perf already implements the bits correctly for Sandy Bridge
and later. This patch patches it up for Nehalem and Westmere.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jolsa@kernel.org
Link: http://lkml.kernel.org/r/1456871124-15985-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-08 12:19:13 +01:00
Stephane Eranian
b3e6246336 perf/x86/pebs: Add proper PEBS constraints for Broadwell
This patch adds a Broadwell specific PEBS event constraint table.

Broadwell has a fix for the HT corruption bug erratum HSD29 on
Haswell. Therefore, there is no need to mark events 0xd0, 0xd1, 0xd2,
0xd3 has requiring the exclusive mode across both sibling HT threads.
This holds true for regular counting and sampling (see core.c) and
PEBS (ds.c) which we fix in this patch.

In doing so, we relax evnt scheduling for these events, they can now
be programmed on any 4 counters without impacting what is measured on
the sibling thread.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@redhat.com
Cc: adrian.hunter@intel.com
Cc: jolsa@redhat.com
Cc: kan.liang@intel.com
Cc: namhyung@kernel.org
Link: http://lkml.kernel.org/r/1457034642-21837-4-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-08 12:19:12 +01:00
Jiri Olsa
e72daf3f4d perf/x86/intel: Use PAGE_SIZE for PEBS buffer size on Core2
Using PAGE_SIZE buffers makes the WRMSR to PERF_GLOBAL_CTRL in
intel_pmu_enable_all() mysteriously hang on Core2. As a workaround, we
don't do this.

The hard lockup is easily triggered by running 'perf test attr'
repeatedly. Most of the time it gets stuck on sample session with
small periods.

  # perf test attr -vv
  14: struct perf_event_attr setup                             :
  --- start ---
  ...
    'PERF_TEST_ATTR=/tmp/tmpuEKz3B /usr/bin/perf record -o /tmp/tmpuEKz3B/perf.data -c 123 kill >/dev/null 2>&1' ret 1

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160301190352.GA8355@krava.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-08 12:18:32 +01:00
Borislav Petkov
27f6d22b03 perf/x86: Move perf_event.h to its new home
Now that all functionality has been moved to arch/x86/events/, move the
perf_event.h header and adjust include paths.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1455098123-11740-18-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 10:11:36 +01:00
Borislav Petkov
7010d12913 perf/x86: Move perf_event_intel_ds.c ......... => x86/events/intel/ds.c
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1455098123-11740-6-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 10:09:46 +01:00