Commit Graph

809 Commits

Author SHA1 Message Date
Stephane Eranian
fc17db8aa4 perf/x86/intel: Check PEBS status correctly
The kernel cannot disambiguate when 2+ PEBS counters overflow at the
same time. This is what the comment for this code suggests.  However,
I see the comparison is done with the unfiltered p->status which is a
copy of IA32_PERF_GLOBAL_STATUS at the time of the sample. This
register contains more than the PEBS counter overflow bits. It also
includes many other bits which could also be set.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201126110922.317681-2-namhyung@kernel.org
2020-12-03 10:00:26 +01:00
Namhyung Kim
5debf02131 perf/x86/intel: Fix a warning on x86_pmu_stop() with large PEBS
The commit 3966c3feca ("x86/perf/amd: Remove need to check "running"
bit in NMI handler") introduced this.  It seems x86_pmu_stop can be
called recursively (like when it losts some samples) like below:

  x86_pmu_stop
    intel_pmu_disable_event  (x86_pmu_disable)
      intel_pmu_pebs_disable
        intel_pmu_drain_pebs_nhm  (x86_pmu_drain_pebs_buffer)
          x86_pmu_stop

While commit 35d1ce6bec ("perf/x86/intel/ds: Fix x86_pmu_stop
warning for large PEBS") fixed it for the normal cases, there's
another path to call x86_pmu_stop() recursively when a PEBS error was
detected (like two or more counters overflowed at the same time).

Like in the Kan's previous fix, we can skip the interrupt accounting
for large PEBS, so check the iregs which is set for PMI only.

Fixes: 3966c3feca ("x86/perf/amd: Remove need to check "running" bit in NMI handler")
Reported-by: John Sperbeck <jsperbeck@google.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201126110922.317681-1-namhyung@kernel.org
2020-12-03 10:00:26 +01:00
Sami Tolvanen
ebd19fc372 perf/x86: fix sysfs type mismatches
This change switches rapl to use PMU_FORMAT_ATTR, and fixes two other
macros to use device_attribute instead of kobj_attribute to avoid
callback type mismatches that trip indirect call checking with Clang's
Control-Flow Integrity (CFI).

Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20201113183126.1239404-1-samitolvanen@google.com
2020-11-17 13:15:38 +01:00
Arnd Bergmann
1a8cfa24e2 perf/x86/intel/uncore: Fix Add BW copypasta
gcc -Wextra points out a duplicate initialization of one array
member:

arch/x86/events/intel/uncore_snb.c:478:37: warning: initialized field overwritten [-Woverride-init]
  478 |  [SNB_PCI_UNCORE_IMC_DATA_READS]  = { SNB_UNCORE_PCI_IMC_DATA_WRITES_BASE,

The only sensible explanation is that a duplicate 'READS' was used
instead of the correct 'WRITES', so change it back.

Fixes: 24633d901e ("perf/x86/intel/uncore: Add BW counters for GT, IA and IO breakdown")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201026215203.3893972-1-arnd@kernel.org
2020-11-10 18:38:40 +01:00
Stephane Eranian
cadbaa039b perf/x86/intel: Make anythread filter support conditional
Starting with Arch Perfmon v5, the anythread filter on generic counters may be
deprecated. The current kernel was exporting the any filter without checking.
On Icelake, it means you could do cpu/event=0x3c,any/ even though the filter
does not exist. This patch corrects the problem by relying on the CPUID 0xa leaf
function to determine if anythread is supported or not as described in the
Intel SDM Vol3b 18.2.5.1 AnyThread Deprecation section.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201028194247.3160610-1-eranian@google.com
2020-11-09 18:12:36 +01:00
Peter Zijlstra
e506d1dac0 perf/x86: Make dummy_iregs static
Having pt_regs on-stack is unfortunate, it's 168 bytes. Since it isn't
actually used, make it a static variable. This both gets if off the
stack and ensures it gets 0 initialized, just in case someone does
look at it.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201030151955.324273677@infradead.org
2020-11-09 18:12:35 +01:00
Peter Zijlstra
9dfa9a5c9b perf/x86: Reduce stack usage for x86_pmu::drain_pebs()
intel_pmu_drain_pebs_*() is typically called from handle_pmi_common(),
both have an on-stack struct perf_sample_data, which is *big*. Rewire
things so that drain_pebs() can use the one handle_pmi_common() has.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201030151955.054099690@infradead.org
2020-11-09 18:12:33 +01:00
Peter Zijlstra
267fb27352 perf: Reduce stack usage of perf_output_begin()
__perf_output_begin() has an on-stack struct perf_sample_data in the
unlikely case it needs to generate a LOST record. However, every call
to perf_output_begin() must already have a perf_sample_data on-stack.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201030151954.985416146@infradead.org
2020-11-09 18:12:33 +01:00
Linus Torvalds
3bff6112c8 These are the performance events changes for v5.10:
x86 Intel updates:
 
  - Add Jasper Lake support
 
  - Add support for TopDown metrics on Ice Lake
 
  - Fix Ice Lake & Tiger Lake uncore support, add Snow Ridge support
 
  - Add a PCI sub driver to support uncore PMUs where the PCI resources
    have been claimed already - extending the range of supported systems.
 
 x86 AMD updates:
 
  - Restore 'perf stat -a' behaviour to program the uncore PMU
    to count all CPU threads.
 
  - Fix setting the proper count when sampling Large Increment
    per Cycle events / 'paired' events.
 
  - Fix IBS Fetch sampling on F17h and some other IBS fine tuning,
    greatly reducing the number of interrupts when large sample
    periods are specified.
 
  - Extends Family 17h RAPL support to also work on compatible
    F19h machines.
 
 Core code updates:
 
  - Fix race in perf_mmap_close()
 
  - Add PERF_EV_CAP_SIBLING, to denote that sibling events should be
    closed if the leader is removed.
 
  - Smaller fixes and updates.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAl+Ef40RHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1h7NQ//ZdQ26Yg79ZaxBX1QSINJ9AgXDi6rXs75
 qU9qNwr/6EF+633RZoPQGAE0Iy5v6h7iLFokcJzM9+kK/rE3ax44tSnPlcMa0+6N
 SHXKCa5iL+hH7o2Spo2MZwCYseH79rloX3TSH7ajnN3X8PvwgWshF0lUE3WEWtCs
 eHSojdCk43IuL9TpusuNOBM2FvgnheFYWiMbFHd0MTBUMxul30sLVCG8IIWCPA+q
 TwG4RJS3X42VbL3SuAGFmOv4OmqNsfkvHvjpDs4NF07tRB9zjXzGrxmGhgSw0NAN
 2KK25qbmrpKATIb4Eqsgk/yikX/SCrDEXrjhg3r8FnyPvRfctq1crZjjf672PI2E
 bDda76dH6Lq9jv5fsyJjas5OsYdMKBCnA+tGQxXPGbmTXeEcYMRbDnwhYnevI/Q/
 8pP+xstF0pmBA3tvpDPrQnYH72Qt7CLJSdcTB15NqZftU2tJxaAyJGx4gJy33jxQ
 wu6BIEGHQ7onQYiIyTwsBHyz6xNsF/CRHwAPcGdYrRRbXB5K5nxHiXNb4awciTMx
 2HF31/S4OqURNpfcpxOQo+1fb/cLqj3loGqE4jCTwkbS3lrHcAcfxyv9QNn77l1f
 hdQ0jworbUNVLUYEUQz1bkZ06GD3LSSas2ZlY1NNdHo62mjyXMQmgirNcZmrFgWl
 tl2gNFAU9x4=
 =2fuY
 -----END PGP SIGNATURE-----

Merge tag 'perf-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull performance events updates from Ingo Molnar:
 "x86 Intel updates:

   - Add Jasper Lake support

   - Add support for TopDown metrics on Ice Lake

   - Fix Ice Lake & Tiger Lake uncore support, add Snow Ridge support

   - Add a PCI sub driver to support uncore PMUs where the PCI resources
     have been claimed already - extending the range of supported
     systems.

  x86 AMD updates:

   - Restore 'perf stat -a' behaviour to program the uncore PMU to count
     all CPU threads.

   - Fix setting the proper count when sampling Large Increment per
     Cycle events / 'paired' events.

   - Fix IBS Fetch sampling on F17h and some other IBS fine tuning,
     greatly reducing the number of interrupts when large sample periods
     are specified.

   - Extends Family 17h RAPL support to also work on compatible F19h
     machines.

  Core code updates:

   - Fix race in perf_mmap_close()

   - Add PERF_EV_CAP_SIBLING, to denote that sibling events should be
     closed if the leader is removed.

   - Smaller fixes and updates"

* tag 'perf-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
  perf/core: Fix race in the perf_mmap_close() function
  perf/x86: Fix n_metric for cancelled txn
  perf/x86: Fix n_pair for cancelled txn
  x86/events/amd/iommu: Fix sizeof mismatch
  perf/x86/intel: Check perf metrics feature for each CPU
  perf/x86/intel: Fix Ice Lake event constraint table
  perf/x86/intel/uncore: Fix the scale of the IMC free-running events
  perf/x86/intel/uncore: Fix for iio mapping on Skylake Server
  perf/x86/msr: Add Jasper Lake support
  perf/x86/intel: Add Jasper Lake support
  perf/x86/intel/uncore: Reduce the number of CBOX counters
  perf/x86/intel/uncore: Update Ice Lake uncore units
  perf/x86/intel/uncore: Split the Ice Lake and Tiger Lake MSR uncore support
  perf/x86/intel/uncore: Support PCIe3 unit on Snow Ridge
  perf/x86/intel/uncore: Generic support for the PCI sub driver
  perf/x86/intel/uncore: Factor out uncore_pci_pmu_unregister()
  perf/x86/intel/uncore: Factor out uncore_pci_pmu_register()
  perf/x86/intel/uncore: Factor out uncore_pci_find_dev_pmu()
  perf/x86/intel/uncore: Factor out uncore_pci_get_dev_die_info()
  perf/amd/uncore: Inform the user how many counters each uncore PMU has
  ...
2020-10-12 14:14:35 -07:00
Peter Zijlstra
3dbde69575 perf/x86: Fix n_metric for cancelled txn
When a group that has TopDown members is failed to be scheduled, any
later TopDown groups will not return valid values.

Here is an example.

A background perf that occupies all the GP counters and the fixed
counter 1.
 $perf stat -e "{cycles,cycles,cycles,cycles,cycles,cycles,cycles,
                 cycles,cycles}:D" -a

A user monitors a TopDown group. It works well, because the fixed
counter 3 and the PERF_METRICS are available.
 $perf stat -x, --topdown -- ./workload
   retiring,bad speculation,frontend bound,backend bound,
   18.0,16.1,40.4,25.5,

Then the user tries to monitor a group that has TopDown members.
Because of the cycles event, the group is failed to be scheduled.
 $perf stat -x, -e '{slots,topdown-retiring,topdown-be-bound,
                     topdown-fe-bound,topdown-bad-spec,cycles}'
                     -- ./workload
    <not counted>,,slots,0,0.00,,
    <not counted>,,topdown-retiring,0,0.00,,
    <not counted>,,topdown-be-bound,0,0.00,,
    <not counted>,,topdown-fe-bound,0,0.00,,
    <not counted>,,topdown-bad-spec,0,0.00,,
    <not counted>,,cycles,0,0.00,,

The user tries to monitor a TopDown group again. It doesn't work anymore.
 $perf stat -x, --topdown -- ./workload

    ,,,,,

In a txn, cancel_txn() is to truncate the event_list for a canceled
group and update the number of events added in this transaction.
However, the number of TopDown events added in this transaction is not
updated. The kernel will probably fail to add new Topdown events.

Fixes: 7b2c05a15d ("perf/x86/intel: Generic support for hardware TopDown metrics")
Reported-by: Andi Kleen <ak@linux.intel.com>
Reported-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lkml.kernel.org/r/20201005082611.GH2628@hirez.programming.kicks-ass.net
2020-10-06 15:18:17 +02:00
Peter Zijlstra
871a93b0aa perf/x86: Fix n_pair for cancelled txn
Kan reported that n_metric gets corrupted for cancelled transactions;
a similar issue exists for n_pair for AMD's Large Increment thing.

The problem was confirmed and confirmed fixed by Kim using:

  sudo perf stat -e "{cycles,cycles,cycles,cycles}:D" -a sleep 10 &

  # should succeed:
  sudo perf stat -e "{fp_ret_sse_avx_ops.all}:D" -a workload

  # should fail:
  sudo perf stat -e "{fp_ret_sse_avx_ops.all,fp_ret_sse_avx_ops.all,cycles}:D" -a workload

  # previously failed, now succeeds with this patch:
  sudo perf stat -e "{fp_ret_sse_avx_ops.all}:D" -a workload

Fixes: 5738891229 ("perf/x86/amd: Add support for Large Increment per Cycle Events")
Reported-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Kim Phillips <kim.phillips@amd.com>
Link: https://lkml.kernel.org/r/20201005082516.GG2628@hirez.programming.kicks-ass.net
2020-10-06 15:18:17 +02:00
Colin Ian King
59d5396a46 x86/events/amd/iommu: Fix sizeof mismatch
An incorrect sizeof is being used, struct attribute ** is not correct,
it should be struct attribute *. Note that since ** is the same size as
* this is not causing any issues.  Improve this fix by using sizeof(*attrs)
as this allows us to not even reference the type of the pointer.

Addresses-Coverity: ("Sizeof not portable (SIZEOF_MISMATCH)")
Fixes: 5168654630 ("x86/events/amd/iommu: Fix sysfs perf attribute groups")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201001113900.58889-1-colin.king@canonical.com
2020-10-03 16:30:56 +02:00
Kan Liang
80a5ce116f perf/x86/intel: Check perf metrics feature for each CPU
It might be possible that different CPUs have different CPU metrics on a
platform. In this case, writing the GLOBAL_CTRL_EN_PERF_METRICS bit to
the GLOBAL_CTRL register of a CPU, which doesn't support the TopDown
perf metrics feature, causes MSR access error.

Current TopDown perf metrics feature is enumerated using the boot CPU's
PERF_CAPABILITIES MSR. The MSR only indicates the boot CPU supports this
feature.

Check the PERF_CAPABILITIES MSR for each CPU. If any CPU doesn't support
the perf metrics feature, disable the feature globally.

Fixes: 59a854e2f3 ("perf/x86/intel: Support TopDown metrics on Ice Lake")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201001211711.25708-1-kan.liang@linux.intel.com
2020-10-03 16:30:56 +02:00
Kan Liang
010cb00265 perf/x86/intel: Fix Ice Lake event constraint table
An error occues when sampling non-PEBS INST_RETIRED.PREC_DIST(0x01c0)
event.

  perf record -e cpu/event=0xc0,umask=0x01/ -- sleep 1
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument)
  for event (cpu/event=0xc0,umask=0x01/).
  /bin/dmesg | grep -i perf may provide additional information.

The idxmsk64 of the event is set to 0. The event never be successfully
scheduled.

The event should be limit to the fixed counter 0.

Fixes: 6017608936 ("perf/x86/intel: Add Icelake support")
Reported-by: Yi, Ammy <ammy.yi@intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200928134726.13090-1-kan.liang@linux.intel.com
2020-09-29 09:57:02 +02:00
Kan Liang
8191016a02 perf/x86/intel/uncore: Fix the scale of the IMC free-running events
The "MiB" result of the IMC free-running bandwidth events,
uncore_imc_free_running/read/ and uncore_imc_free_running/write/ are 16
times too small.

The "MiB" value equals the raw IMC free-running bandwidth counter value
times a "scale" which is inaccurate.

The IMC free-running bandwidth events should be incremented per 64B
cache line, not DWs (4 bytes). The "scale" should be 6.103515625e-5.
Fix the "scale" for both Snow Ridge and Ice Lake.

Fixes: 2b3b76b5ec ("perf/x86/intel/uncore: Add Ice Lake server uncore support")
Fixes: ee49532b38 ("perf/x86/intel/uncore: Add IMC uncore support for Snow Ridge")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200928133240.12977-1-kan.liang@linux.intel.com
2020-09-29 09:57:02 +02:00
Alexander Antonov
f797f05d91 perf/x86/intel/uncore: Fix for iio mapping on Skylake Server
Introduced early attributes /sys/devices/uncore_iio_<pmu_idx>/die* are
initialized by skx_iio_set_mapping(), however, for example, for multiple
segment platforms skx_iio_get_topology() returns -EPERM before a list of
attributes in skx_iio_mapping_group will have been initialized.
As a result the list is being NULL. Thus the warning
"sysfs: (bin_)attrs not set by subsystem for group: uncore_iio_*/" appears
and uncore_iio pmus are not available in sysfs. Clear IIO attr_update
to properly handle the cases when topology information cannot be
retrieved.

Fixes: bb42b3d397 ("perf/x86/intel/uncore: Expose an Uncore unit to IIO PMON mapping")
Reported-by: Kyle Meyer <kyle.meyer@hpe.com>
Suggested-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Alexei Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lkml.kernel.org/r/20200928102133.61041-1-alexander.antonov@linux.intel.com
2020-09-29 09:57:02 +02:00
Kan Liang
c3bb8a9fa3 perf/x86/msr: Add Jasper Lake support
The Jasper Lake processor is also a Tremont microarchitecture. From the
perspective of perf MSR, there is nothing changed compared with
Elkhart Lake.
Share the code path with Elkhart Lake.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1601296242-32763-2-git-send-email-kan.liang@linux.intel.com
2020-09-29 09:57:02 +02:00
Kan Liang
dbfd638889 perf/x86/intel: Add Jasper Lake support
The Jasper Lake processor is also a Tremont microarchitecture. From the
perspective of Intel PMU, there is nothing changed compared with
Elkhart Lake.
Share the perf code with Elkhart Lake.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1601296242-32763-1-git-send-email-kan.liang@linux.intel.com
2020-09-29 09:57:01 +02:00
Kan Liang
ee13938543 perf/x86/intel/uncore: Reduce the number of CBOX counters
An oops is triggered by the fuzzy test.

[  327.853081] unchecked MSR access error: RDMSR from 0x70c at rIP:
0xffffffffc082c820 (uncore_msr_read_counter+0x10/0x50 [intel_uncore])
[  327.853083] Call Trace:
[  327.853085]  <IRQ>
[  327.853089]  uncore_pmu_event_start+0x85/0x170 [intel_uncore]
[  327.853093]  uncore_pmu_event_add+0x1a4/0x410 [intel_uncore]
[  327.853097]  ? event_sched_in.isra.118+0xca/0x240

There are 2 GP counters for each CBOX, but the current code claims 4
counters. Accessing the invalid registers triggers the oops.

Fixes: 6e394376ee ("perf/x86/intel/uncore: Add Intel Icelake uncore support")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200925134905.8839-3-kan.liang@linux.intel.com
2020-09-29 09:57:01 +02:00
Kan Liang
8f5d41f3a0 perf/x86/intel/uncore: Update Ice Lake uncore units
There are some updates for the Icelake model specific uncore performance
monitors. (The update can be found at 10th generation intel core
processors families specification update Revision 004, ICL068)

1) Counter 0 of ARB uncore unit is not available for software use
2) The global 'enable bit' (bit 29) and 'freeze bit' (bit 31) of
   MSR_UNC_PERF_GLOBAL_CTRL cannot be used to control counter behavior.
   Needs to use local enable in event select MSR.

Accessing the modified bit/registers will be ignored by HW. Users may
observe inaccurate results with the current code.

The changes of the MSR_UNC_PERF_GLOBAL_CTRL imply that groups cannot be
read atomically anymore. Although the error of the result for a group
becomes a bit bigger, it still far lower than not using a group. The
group support is still kept. Only Remove the *_box() related
implementation.

Since the counter 0 of ARB uncore unit is not available, update the MSR
address for the ARB uncore unit.

There is no change for IMC uncore unit, which only include free-running
counters.

Fixes: 6e394376ee ("perf/x86/intel/uncore: Add Intel Icelake uncore support")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200925134905.8839-2-kan.liang@linux.intel.com
2020-09-29 09:57:01 +02:00
Kan Liang
8abbcfefb5 perf/x86/intel/uncore: Split the Ice Lake and Tiger Lake MSR uncore support
Previously, the MSR uncore for the Ice Lake and Tiger Lake are
identical. The code path is shared. However, with recent update, the
global MSR_UNC_PERF_GLOBAL_CTRL register and ARB uncore unit are changed
for the Ice Lake. Split the Ice Lake and Tiger Lake MSR uncore support.

The changes only impact the MSR ops() and the ARB uncore unit. Other
codes can still be shared between the Ice Lake and the Tiger Lake.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200925134905.8839-1-kan.liang@linux.intel.com
2020-09-29 09:57:00 +02:00
Kan Liang
a3b1e8451d perf/x86/intel/uncore: Support PCIe3 unit on Snow Ridge
The Snow Ridge integrated PCIe3 uncore unit can be used to collect
performance data, e.g. utilization, between PCIe devices, plugged into
the PCIe port, and the components (in M2IOSF) responsible for
translating and managing requests to/from the device. The performance
data is very useful for analyzing the performance of PCIe devices.

The device with the PCIe3 uncore PMON units is owned by the portdrv_pci
driver. Create a PCI sub driver for the PCIe3 uncore PMON units.

Here are some difference between PCIe3 uncore unit and other uncore
pci units.
- There may be several Root Ports on a system. But the uncore counters
  only exist in the Root Port A. A user can configure the channel mask
  to collect the data from other Root Ports.
- The event format of the PCIe3 uncore unit is the same as IIO unit of
  SKX.
- The Control Register of PCIe3 uncore unit is 64 bits.
- The offset of each counters is 8, which is the same as M2M unit of
  SNR.
- New MSR addresses for unit control, counter and counter config.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1600094060-82746-7-git-send-email-kan.liang@linux.intel.com
2020-09-24 15:55:52 +02:00
Kan Liang
95a7fc7744 perf/x86/intel/uncore: Generic support for the PCI sub driver
Some uncore counters may be located in the configuration space of a PCI
device, which already has a bonded driver. Currently, the uncore driver
cannot register a PCI uncore PMU for these counters, because, to
register a PCI uncore PMU, the uncore driver must be bond to the device.
However, one device can only have one bonded driver.

Add an uncore PCI sub driver to support such kind of devices.

The sub driver doesn't own the device. In initialization, the sub
driver searches the device via pci_get_device(), and register the
corresponding PMU for the device. In the meantime, the sub driver
registers a PCI bus notifier, which is used to notify the sub driver
once the device is removed. The sub driver can unregister the PMU
accordingly.

The sub driver only searches the devices defined in its id table. The
id table varies on different platforms, which will be implemented in the
following platform-specific patch.

Suggested-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1600094060-82746-6-git-send-email-kan.liang@linux.intel.com
2020-09-24 15:55:51 +02:00
Kan Liang
cdcce92a3a perf/x86/intel/uncore: Factor out uncore_pci_pmu_unregister()
The PMU unregistration in the uncore PCI sub driver is similar as the
normal PMU unregistration for a PCI device. The codes to unregister a
PCI PMU can be shared.

Factor out uncore_pci_pmu_unregister(), which will be used later.

Use uncore_pci_get_dev_die_info() to replace the codes which retrieve
the socket and die informaion.

The pci_set_drvdata() is not included in uncore_pci_pmu_unregister() as
well, because the uncore PCI sub driver will not touch the private
driver data pointer of the device.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1600094060-82746-5-git-send-email-kan.liang@linux.intel.com
2020-09-24 15:55:51 +02:00
Kan Liang
16fa64315c perf/x86/intel/uncore: Factor out uncore_pci_pmu_register()
The PMU registration in the uncore PCI sub driver is similar as the
normal PMU registration for a PCI device. The codes to register a PCI
PMU can be shared.

Factor out uncore_pci_pmu_register(), which will be used later.

The pci_set_drvdata() is not included in uncore_pci_pmu_register(). The
uncore PCI sub driver doesn't own the PCI device. It will not touch the
private driver data pointer for the device.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1600094060-82746-4-git-send-email-kan.liang@linux.intel.com
2020-09-24 15:55:51 +02:00
Kan Liang
8ed2ccaa3f perf/x86/intel/uncore: Factor out uncore_pci_find_dev_pmu()
When an uncore PCI sub driver gets a remove notification, the
corresponding PMU has to be retrieved and unregistered. The codes, which
find the corresponding PMU by comparing the pci_device_id table, can be
shared.

Factor out uncore_pci_find_dev_pmu(), which will be used later.

There is no functional change.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1600094060-82746-3-git-send-email-kan.liang@linux.intel.com
2020-09-24 15:55:50 +02:00
Kan Liang
fe6507338d perf/x86/intel/uncore: Factor out uncore_pci_get_dev_die_info()
The socket and die information is required to register/unregister a PMU
in the uncore PCI sub driver. The codes, which get the socket and die
information from a BUS number, can be shared.

Factor out uncore_pci_get_dev_die_info(), which will be used later.

There is no functional change.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1600094060-82746-2-git-send-email-kan.liang@linux.intel.com
2020-09-24 15:55:50 +02:00
Kim Phillips
9ed9647dc0 perf/amd/uncore: Inform the user how many counters each uncore PMU has
Previously, the uncore driver would say "NB counters detected" on F17h
machines, which don't have NorthBridge (NB) counters.  They have Data
Fabric (DF) counters.  Just use the pmu.name to inform users which pmu
to use and its associated counter count.

F17h dmesg BEFORE:

amd_uncore: AMD NB counters detected
amd_uncore: AMD LLC counters detected

F17h dmesg AFTER:

amd_uncore: 4 amd_df counters detected
amd_uncore: 6 amd_l3 counters detected

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921144330.6331-5-kim.phillips@amd.com
2020-09-24 15:55:50 +02:00
Kim Phillips
87a54a1fd5 perf/amd/uncore: Allow F19h user coreid, threadmask, and sliceid specification
On Family 19h, the driver checks for a populated 2-bit threadmask in
order to establish that the user wants to measure individual slices,
individual cores (only one can be measured at a time), and lets
the user also directly specify enallcores and/or enallslices if
desired.

Example F19h invocation to measure L3 accesses (event 4, umask 0xff)
by the first thread (id 0 -> mask 0x1) of the first core (id 0) on the
first slice (id 0):

perf stat -a -e instructions,amd_l3/umask=0xff,event=0x4,coreid=0,threadmask=1,sliceid=0,enallcores=0,enallslices=0/ <workload>

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921144330.6331-4-kim.phillips@amd.com
2020-09-24 15:55:50 +02:00
Kim Phillips
8170f386f1 perf/amd/uncore: Allow F17h user threadmask and slicemask specification
Continue to fully populate either one of threadmask or slicemask if the
user doesn't.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921144330.6331-3-kim.phillips@amd.com
2020-09-24 15:55:49 +02:00
Kim Phillips
06f2c24584 perf/amd/uncore: Prepare to scale for more attributes that vary per family
Replace AMD_FORMAT_ATTR with the more apropos DEFINE_UNCORE_FORMAT_ATTR
stolen from arch/x86/events/intel/uncore.h.  This way we can clearly
see the bit-variants of each of the attributes that want to have
the same name across families.

Also unroll AMD_ATTRIBUTE because we are going to separately add
new attributes that differ between DF and L3.

Also clean up the if-Family 17h-else logic in amd_uncore_init.

This is basically a rewrite of commit da6adaea2b
("perf/x86/amd/uncore: Update sysfs attributes for Family17h processors").

No functional changes.

Tested F17h+ /sys/bus/event_source/devices/amd_{l3,df}/format/*
content remains unchanged:

/sys/bus/event_source/devices/amd_l3/format/event:config:0-7
/sys/bus/event_source/devices/amd_l3/format/umask:config:8-15
/sys/bus/event_source/devices/amd_df/format/event:config:0-7,32-35,59-60
/sys/bus/event_source/devices/amd_df/format/umask:config:8-15

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921144330.6331-2-kim.phillips@amd.com
2020-09-24 15:55:49 +02:00
Kim Phillips
221bfce5eb arch/x86/amd/ibs: Fix re-arming IBS Fetch
Stephane Eranian found a bug in that IBS' current Fetch counter was not
being reset when the driver would write the new value to clear it along
with the enable bit set, and found that adding an MSR write that would
first disable IBS Fetch would make IBS Fetch reset its current count.

Indeed, the PPR for AMD Family 17h Model 31h B0 55803 Rev 0.54 - Sep 12,
2019 states "The periodic fetch counter is set to IbsFetchCnt [...] when
IbsFetchEn is changed from 0 to 1."

Explicitly set IbsFetchEn to 0 and then to 1 when re-enabling IBS Fetch,
so the driver properly resets the internal counter to 0 and IBS
Fetch starts counting again.

A family 15h machine tested does not have this problem, and the extra
wrmsr is also not needed on Family 19h, so only do the extra wrmsr on
families 16h through 18h.

Reported-by: Stephane Eranian <stephane.eranian@google.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
[peterz: optimized]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
2020-09-10 11:19:36 +02:00
Kim Phillips
a77259bdcb perf/x86/rapl: Add AMD Fam19h RAPL support
Family 19h RAPL support did not change from Family 17h; extend
the existing Fam17h support to work on Family 19h too.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200908214740.18097-8-kim.phillips@amd.com
2020-09-10 11:19:36 +02:00
Kim Phillips
8b0bed7d41 perf/x86/amd/ibs: Support 27-bit extended Op/cycle counter
IBS hardware with the OpCntExt feature gets a 7-bit wider internal
counter.  Both the maximum and current count bitfields in the
IBS_OP_CTL register are extended to support reading and writing it.

No changes are necessary to the driver for handling the extra
contiguous current count bits (IbsOpCurCnt), as the driver already
passes through 32 bits of that field.  However, the driver has to do
some extra bit manipulation when converting from a period to the
non-contiguous (although conveniently aligned) extra bits in the
IbsOpMaxCnt bitfield.

This decreases IBS Op interrupt overhead when the period is over
1,048,560 (0xffff0), which would previously activate the driver's
software counter.  That threshold is now 134,217,712 (0x7fffff0).

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200908214740.18097-7-kim.phillips@amd.com
2020-09-10 11:19:36 +02:00
Kim Phillips
36e1be8ada perf/x86/amd/ibs: Fix raw sample data accumulation
Neither IbsBrTarget nor OPDATA4 are populated in IBS Fetch mode.
Don't accumulate them into raw sample user data in that case.

Also, in Fetch mode, add saving the IBS Fetch Control Extended MSR.

Technically, there is an ABI change here with respect to the IBS raw
sample data format, but I don't see any perf driver version information
being included in perf.data file headers, but, existing users can detect
whether the size of the sample record has reduced by 8 bytes to
determine whether the IBS driver has this fix.

Fixes: 904cb3677f ("perf/x86/amd/ibs: Update IBS MSRs and feature definitions")
Reported-by: Stephane Eranian <stephane.eranian@google.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200908214740.18097-6-kim.phillips@amd.com
2020-09-10 11:19:35 +02:00
Kim Phillips
680d696350 perf/x86/amd/ibs: Don't include randomized bits in get_ibs_op_count()
get_ibs_op_count() adds hardware's current count (IbsOpCurCnt) bits
to its count regardless of hardware's valid status.

According to the PPR for AMD Family 17h Model 31h B0 55803 Rev 0.54,
if the counter rolls over, valid status is set, and the lower 7 bits
of IbsOpCurCnt are randomized by hardware.

Don't include those bits in the driver's event count.

Fixes: 8b1e13638d ("perf/x86-ibs: Fix usage of IBS op current count")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
2020-09-10 11:19:35 +02:00
Kim Phillips
26e52558ea perf/x86/amd: Fix sampling Large Increment per Cycle events
Commit 5738891229 ("perf/x86/amd: Add support for Large Increment
per Cycle Events") mistakenly zeroes the upper 16 bits of the count
in set_period().  That's fine for counting with perf stat, but not
sampling with perf record when only Large Increment events are being
sampled.  To enable sampling, we sign extend the upper 16 bits of the
merged counter pair as described in the Family 17h PPRs:

"Software wanting to preload a value to a merged counter pair writes the
high-order 16-bit value to the low-order 16 bits of the odd counter and
then writes the low-order 48-bit value to the even counter. Reading the
even counter of the merged counter pair returns the full 64-bit value."

Fixes: 5738891229 ("perf/x86/amd: Add support for Large Increment per Cycle Events")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
2020-09-10 11:19:35 +02:00
Kim Phillips
c8fe99d070 perf/amd/uncore: Set all slices and threads to restore perf stat -a behaviour
Commit 2f217d58a8 ("perf/x86/amd/uncore: Set the thread mask for
F17h L3 PMCs") inadvertently changed the uncore driver's behaviour
wrt perf tool invocations with or without a CPU list, specified with
-C / --cpu=.

Change the behaviour of the driver to assume the former all-cpu (-a)
case, which is the more commonly desired default.  This fixes
'-a -A' invocations without explicit cpu lists (-C) to not count
L3 events only on behalf of the first thread of the first core
in the L3 domain.

BEFORE:

Activity performed by the first thread of the last core (CPU#43) in
CPU#40's L3 domain is not reported by CPU#40:

sudo perf stat -a -A -e l3_request_g1.caching_l3_cache_accesses taskset -c 43 perf bench mem memcpy -s 32mb -l 100 -f default
...
CPU36                 21,835      l3_request_g1.caching_l3_cache_accesses
CPU40                 87,066      l3_request_g1.caching_l3_cache_accesses
CPU44                 17,360      l3_request_g1.caching_l3_cache_accesses
...

AFTER:

The L3 domain activity is now reported by CPU#40:

sudo perf stat -a -A -e l3_request_g1.caching_l3_cache_accesses taskset -c 43 perf bench mem memcpy -s 32mb -l 100 -f default
...
CPU36                354,891      l3_request_g1.caching_l3_cache_accesses
CPU40              1,780,870      l3_request_g1.caching_l3_cache_accesses
CPU44                315,062      l3_request_g1.caching_l3_cache_accesses
...

Fixes: 2f217d58a8 ("perf/x86/amd/uncore: Set the thread mask for F17h L3 PMCs")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200908214740.18097-2-kim.phillips@amd.com
2020-09-10 11:19:34 +02:00
Kan Liang
35d1ce6bec perf/x86/intel/ds: Fix x86_pmu_stop warning for large PEBS
A warning as below may be triggered when sampling with large PEBS.

[  410.411250] perf: interrupt took too long (72145 > 71975), lowering
kernel.perf_event_max_sample_rate to 2000
[  410.724923] ------------[ cut here ]------------
[  410.729822] WARNING: CPU: 0 PID: 16397 at arch/x86/events/core.c:1422
x86_pmu_stop+0x95/0xa0
[  410.933811]  x86_pmu_del+0x50/0x150
[  410.937304]  event_sched_out.isra.0+0xbc/0x210
[  410.941751]  group_sched_out.part.0+0x53/0xd0
[  410.946111]  ctx_sched_out+0x193/0x270
[  410.949862]  __perf_event_task_sched_out+0x32c/0x890
[  410.954827]  ? set_next_entity+0x98/0x2d0
[  410.958841]  __schedule+0x592/0x9c0
[  410.962332]  schedule+0x5f/0xd0
[  410.965477]  exit_to_usermode_loop+0x73/0x120
[  410.969837]  prepare_exit_to_usermode+0xcd/0xf0
[  410.974369]  ret_from_intr+0x2a/0x3a
[  410.977946] RIP: 0033:0x40123c
[  411.079661] ---[ end trace bc83adaea7bb664a ]---

In the non-overflow context, e.g., context switch, with large PEBS, perf
may stop an event twice. An example is below.

  //max_samples_per_tick is adjusted to 2
  //NMI is triggered
  intel_pmu_handle_irq()
     handle_pmi_common()
       drain_pebs()
         __intel_pmu_pebs_event()
           perf_event_overflow()
             __perf_event_account_interrupt()
               hwc->interrupts = 1
               return 0
  //A context switch happens right after the NMI.
  //In the same tick, the perf_throttled_seq is not changed.
  perf_event_task_sched_out()
     perf_pmu_sched_task()
       intel_pmu_drain_pebs_buffer()
         __intel_pmu_pebs_event()
           perf_event_overflow()
             __perf_event_account_interrupt()
               ++hwc->interrupts >= max_samples_per_tick
               return 1
           x86_pmu_stop();  # First stop
     perf_event_context_sched_out()
       task_ctx_sched_out()
         ctx_sched_out()
           event_sched_out()
             x86_pmu_del()
               x86_pmu_stop();  # Second stop and trigger the warning

Perf should only invoke the perf_event_overflow() in the overflow
context.

Current drain_pebs() is called from:
- handle_pmi_common()			-- overflow context
- intel_pmu_pebs_sched_task()		-- non-overflow context
- intel_pmu_pebs_disable()		-- non-overflow context
- intel_pmu_auto_reload_read()		-- possible overflow context
  With PERF_SAMPLE_READ + PERF_FORMAT_GROUP, the function may be
  invoked in the NMI handler. But, before calling the function, the
  PEBS buffer has already been drained. The __intel_pmu_pebs_event()
  will not be called in the possible overflow context.

To fix the issue, an indicator is required to distinguish between the
overflow context aka handle_pmi_common() and other cases.
The dummy regs pointer can be used as the indicator.

In the non-overflow context, perf should treat the last record the same
as other PEBS records, and doesn't invoke the generic overflow handler.

Fixes: 21509084f9 ("perf/x86/intel: Handle multiple records in the PEBS buffer")
Reported-by: Like Xu <like.xu@linux.intel.com>
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Like Xu <like.xu@linux.intel.com>
Link: https://lkml.kernel.org/r/20200902210649.2743-1-kan.liang@linux.intel.com
2020-09-10 11:19:33 +02:00
Peter Zijlstra
7c9903c9bf x86/perf, static_call: Optimize x86_pmu methods
Replace many of the indirect calls with static_call().

The average PMI time, as measured by perf_sample_event_took()*:

  PRE:    3283.03 [ns]
  POST:   3145.12 [ns]

Which is a ~138 [ns] win per PMI, or a ~4.2% decrease.

[*] on an IVB-EP, using: 'perf record -a -e cycles -- make O=defconfig-build/ -j80'

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20200818135805.338001015@infradead.org
2020-09-01 09:58:06 +02:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Kan Liang
2cb5383b30 perf/x86/intel: Support per-thread RDPMC TopDown metrics
Starts from Ice Lake, the TopDown metrics are directly available as
fixed counters and do not require generic counters. Also, the TopDown
metrics can be collected per thread. Extend the RDPMC usage to support
per-thread TopDown metrics.

The RDPMC index of the PERF_METRICS will be output if RDPMC users ask
for the RDPMC index of the metrics events.

To support per thread RDPMC TopDown, the metrics and slots counters have
to be saved/restored during the context switching.

The last_period and period_left are not used in the counting mode. Use
the fields for saved_metric and saved_slots.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-12-kan.liang@linux.intel.com
2020-08-18 16:34:37 +02:00
Kan Liang
59a854e2f3 perf/x86/intel: Support TopDown metrics on Ice Lake
Ice Lake supports the hardware TopDown metrics feature, which can free
up the scarce GP counters.

Update the event constraints for the metrics events. The metric counters
do not exist, which are mapped to a dummy offset. The sharing between
multiple users of the same metric without multiplexing is not allowed.

Implement set_topdown_event_period for Ice Lake. The values in
PERF_METRICS MSR are derived from the fixed counter 3. Both registers
should start from zero.

Implement update_topdown_event for Ice Lake. The metric is reported by
multiplying the metric (fraction) with slots. To maintain accurate
measurements, both registers are cleared for each update. The fixed
counter 3 should always be cleared before the PERF_METRICS.

Implement td_attr for the new metrics events and the new slots fixed
counter. Make them visible to the perf user tools.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-11-kan.liang@linux.intel.com
2020-08-18 16:34:37 +02:00
Kan Liang
0e2e45e2de perf/x86: Add a macro for RDPMC offset of fixed counters
The RDPMC base offset of fixed counters is hard-code. Use a meaningful
name to replace the magic number to improve the readability of the code.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-10-kan.liang@linux.intel.com
2020-08-18 16:34:36 +02:00
Kan Liang
7b2c05a15d perf/x86/intel: Generic support for hardware TopDown metrics
Intro
=====

The TopDown Microarchitecture Analysis (TMA) Method is a structured
analysis methodology to identify critical performance bottlenecks in
out-of-order processors. Current perf has supported the method.

The method works well, but there is one problem. To collect the TopDown
events, several GP counters have to be used. If a user wants to collect
other events at the same time, the multiplexing probably be triggered,
which impacts the accuracy.

To free up the scarce GP counters, the hardware TopDown metrics feature
is introduced from Ice Lake. The hardware implements an additional
"metrics" register and a new Fixed Counter 3 that measures pipeline
"slots". The TopDown events can be calculated from them instead.

Events
======

The level 1 TopDown has four metrics. There is no event-code assigned to
the TopDown metrics. Four metric events are exported as separate perf
events, which map to the internal "metrics" counter register. Those
events do not exist in hardware, but can be allocated by the scheduler.

For the event mapping, a special 0x00 event code is used, which is
reserved for fake events. The metric events start from umask 0x10.

When setting up the metric events, they point to the Fixed Counter 3.
They have to be specially handled.
- Add the update_topdown_event() callback to read the additional metrics
  MSR and generate the metrics.
- Add the set_topdown_event_period() callback to initialize metrics MSR
  and the fixed counter 3.
- Add a variable n_metric_event to track the number of the accepted
  metrics events. The sharing between multiple users of the same metric
  without multiplexing is not allowed.
- Only enable/disable the fixed counter 3 when there are no other active
  TopDown events, which avoid the unnecessary writing of the fixed
  control register.
- Disable the PMU when reading the metrics event. The metrics MSR and
  the fixed counter 3 are read separately. The values may be modified by
  an NMI.

All four metric events don't support sampling. Since they will be
handled specially for event update, a flag PERF_X86_EVENT_TOPDOWN is
introduced to indicate this case.

The slots event can support both sampling and counting.
For counting, the flag is also applied.
For sampling, it will be handled normally as other normal events.

Groups
======

The slots event is required in a Topdown group.
To avoid reading the METRICS register multiple times, the metrics and
slots value can only be updated by slots event in a group.
All active slots and metrics events will be updated one time.
Therefore, the slots event must be before any metric events in a Topdown
group.

NMI
======

The METRICS related register may be overflow. The bit 48 of the STATUS
register will be set. If so, PERF_METRICS and Fixed counter 3 are
required to be reset. The patch also update all active slots and
metrics events in the NMI handler.

The update_topdown_event() has to read two registers separately. The
values may be modified by an NMI. PMU has to be disabled before calling
the function.

RDPMC
======

RDPMC is temporarily disabled. A later patch will enable it.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-9-kan.liang@linux.intel.com
2020-08-18 16:34:36 +02:00
Kan Liang
58da7dbe6f perf/x86/intel: Use switch in intel_pmu_disable/enable_event
Currently, the if-else is used in the intel_pmu_disable/enable_event to
check the type of an event. It works well, but with more and more types
added later, e.g., perf metrics, compared to the switch statement, the
if-else may impair the readability of the code.

There is no harm to use the switch statement to replace the if-else
here. Also, some optimizing compilers may compile a switch statement
into a jump-table which is more efficient than if-else for a large
number of cases. The performance gain may not be observed for now,
because the number of cases is only 5, but the benefits may be observed
with more and more types added in the future.

Use switch to replace the if-else in the intel_pmu_disable/enable_event.

If the idx is invalid, print a warning.

For the case INTEL_PMC_IDX_FIXED_BTS in intel_pmu_disable_event, don't
need to check the event->attr.precise_ip. Use return for the case.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-7-kan.liang@linux.intel.com
2020-08-18 16:34:36 +02:00
Kan Liang
bbdbde2a41 perf/x86/intel: Fix the name of perf METRICS
Bit 15 of the PERF_CAPABILITIES MSR indicates that the perf METRICS
feature is supported. The perf METRICS is not a PEBS feature.

Rename pebs_metrics_available perf_metrics.

The bit is not used in the current code. It will be used in a later
patch.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-6-kan.liang@linux.intel.com
2020-08-18 16:34:35 +02:00
Kan Liang
60a2a271cf perf/x86/intel: Name the global status bit in NMI handler
Magic numbers are used in the current NMI handler for the global status
bit. Use a meaningful name to replace the magic numbers to improve the
readability of the code.

Remove a Tab for all GLOBAL_STATUS_* and INTEL_PMC_IDX_FIXED_BTS macros
to reduce the length of the line.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-3-kan.liang@linux.intel.com
2020-08-18 16:34:34 +02:00
Kan Liang
75608cb02e perf/x86: Use event_base_rdpmc for the RDPMC userspace support
The RDPMC index is always re-calculated for the RDPMC userspace support,
which is unnecessary.

The RDPMC index value is stored in the variable event_base_rdpmc for
the kernel usage, which can be used for RDPMC userspace support as well.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-2-kan.liang@linux.intel.com
2020-08-18 16:34:34 +02:00
Vaibhav Shankar
24633d901e perf/x86/intel/uncore: Add BW counters for GT, IA and IO breakdown
Linux only has support to read total DDR reads and writes. Here we
add support to enable bandwidth breakdown-GT, IA and IO. Breakdown
of BW is important to debug and optimize memory access. This can also
be used for telemetry and improving the system software.The offsets for
GT, IA and IO are added and these free running counters can be accessed
via MMIO space.

The BW breakdown can be measured using the following cmd:

  perf stat -e uncore_imc/gt_requests/,uncore_imc/ia_requests/,uncore_imc/io_requests/

             30.57 MiB  uncore_imc/gt_requests/
           1346.13 MiB  uncore_imc/ia_requests/
            190.97 MiB  uncore_imc/io_requests/

       5.984572733 seconds time elapsed

     BW/s = <gt,ia,io>_requests/time elapsed

Signed-off-by: Vaibhav Shankar <vaibhav.shankar@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200814022234.23605-1-vaibhav.shankar@intel.com
2020-08-15 20:24:18 +02:00