linux/arch/x86/events
Kan Liang 0f519f0352 perf/x86/intel/uncore: Support IIO free-running counters on SKX
As of Skylake Server, there are a number of free running counters in
each IIO Box that collect counts of per-box IO clocks and per-port
Input/Output x BW/Utilization.

The free running counters cannot be part of the existing IIO BOX,
because, quoting from Peter Zijlstra:

  "This will result in some (probably) unexpected scheduling artifacts.
   Probably the only way to really cure that is to have the free running
   counters in their own PMU and not share with the GP counters of this
   box."

So let's add a new PMU for the free running counters, as suggested.

The free-running counter is read-only and always active. Counting will
be suspended only when the IIO Box is powered down.

There are three types of IIO free-running counters on Skylake server, IO
CLOCKS counter, BANDWIDTH counters and UTILIZATION counters.
IO CLOCKS counter is a clock of IIO box.
BANDWIDTH counters are to count inbound(PCIe->CPU)/outbound(CPU->PCIe)
bandwidth.
UTILIZATION counters are to count input/output utilization.

The bit width of the free-running counters is 36-bits.

Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@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: eranian@google.com
Link: http://lkml.kernel.org/r/1525371913-10597-6-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-31 12:36:28 +02:00
..
amd perf/x86/amd/power: Do not load AMD power module on !AMD platforms 2018-01-24 13:00:35 +01:00
intel perf/x86/intel/uncore: Support IIO free-running counters on SKX 2018-05-31 12:36:28 +02:00
core.c perf/x86: Fix possible Spectre-v1 indexing for x86_pmu::event_map() 2018-05-05 08:37:28 +02:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile perf/x86/events: Add an AMD-specific Makefile 2017-01-30 12:01:19 +01:00
msr.c perf/x86/msr: Fix possible Spectre-v1 indexing in the MSR driver 2018-05-05 08:37:29 +02:00
perf_event.h Merge branch 'perf/urgent' into perf/core, to pick up fixes 2018-03-24 09:21:47 +01:00