linux/include
Huang Rui c7ab62bfbe perf/x86/amd/power: Add AMD accumulated power reporting mechanism
Introduce an AMD accumlated power reporting mechanism for the Family
15h, Model 60h processor that can be used to calculate the average
power consumed by a processor during a measurement interval. The
feature support is indicated by CPUID Fn8000_0007_EDX[12].

This feature will be implemented both in hwmon and perf. The current
design provides one event to report per package/processor power
consumption by counting each compute unit power value.

Here the gory details of how the computation is done:

* Tsample: compute unit power accumulator sample period
* Tref: the PTSC counter period (PTSC: performance timestamp counter)
* N: the ratio of compute unit power accumulator sample period to the
  PTSC period

* Jmax: max compute unit accumulated power which is indicated by
  MSR_C001007b[MaxCpuSwPwrAcc]

* Jx/Jy: compute unit accumulated power which is indicated by
  MSR_C001007a[CpuSwPwrAcc]

* Tx/Ty: the value of performance timestamp counter which is indicated
  by CU_PTSC MSR_C0010280[PTSC]
* PwrCPUave: CPU average power

i. Determine the ratio of Tsample to Tref by executing CPUID Fn8000_0007.
	N = value of CPUID Fn8000_0007_ECX[CpuPwrSampleTimeRatio[15:0]].

ii. Read the full range of the cumulative energy value from the new
    MSR MaxCpuSwPwrAcc.
	Jmax = value returned.

iii. At time x, software reads CpuSwPwrAcc and samples the PTSC.
	Jx = value read from CpuSwPwrAcc and Tx = value read from PTSC.

iv. At time y, software reads CpuSwPwrAcc and samples the PTSC.
	Jy = value read from CpuSwPwrAcc and Ty = value read from PTSC.

v. Calculate the average power consumption for a compute unit over
time period (y-x). Unit of result is uWatt:

	if (Jy < Jx) // Rollover has occurred
		Jdelta = (Jy + Jmax) - Jx
	else
		Jdelta = Jy - Jx
	PwrCPUave = N * Jdelta * 1000 / (Ty - Tx)

Simple example:

  root@hr-zp:/home/ray/tip# ./tools/perf/perf stat -a -e 'power/power-pkg/' make -j4
    CHK     include/config/kernel.release
    CHK     include/generated/uapi/linux/version.h
    CHK     include/generated/utsrelease.h
    CHK     include/generated/timeconst.h
    CHK     include/generated/bounds.h
    CHK     include/generated/asm-offsets.h
    CALL    scripts/checksyscalls.sh
    CHK     include/generated/compile.h
    SKIPPED include/generated/compile.h
    Building modules, stage 2.
  Kernel: arch/x86/boot/bzImage is ready  (#40)
    MODPOST 4225 modules

   Performance counter stats for 'system wide':

              183.44 mWatts power/power-pkg/

       341.837270111 seconds time elapsed

  root@hr-zp:/home/ray/tip# ./tools/perf/perf stat -a -e 'power/power-pkg/' sleep 10

   Performance counter stats for 'system wide':

                0.18 mWatts power/power-pkg/

        10.012551815 seconds time elapsed

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Ingo Molnar <mingo@kernel.org>
Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
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: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Richter <rric@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: jacob.w.shin@gmail.com
Link: http://lkml.kernel.org/r/1457502306-2559-1-git-send-email-ray.huang@amd.com
[ Fixed the modular build. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:37:15 +01:00
..
acpi ACPI / CPPC: remove redundant mbox_send_message() declaration 2016-02-03 01:09:52 +01:00
asm-generic Merge branch 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-14 16:58:50 -07:00
clocksource
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2016-01-22 11:58:43 -08:00
drm drm/atomic: Allow for holes in connector state, v2. 2016-02-19 13:24:03 +10:00
dt-bindings clk: tegra: Add the APB2APE audio clock on Tegra210 2016-02-02 15:49:29 +01:00
keys
kvm
linux perf/x86/amd/power: Add AMD accumulated power reporting mechanism 2016-03-21 09:37:15 +01:00
math-emu
media [media] vb2: fix nasty vb2_thread regression 2016-02-04 09:13:46 -02:00
memory
misc
net Another small set of fixes: 2016-02-24 16:58:12 -05:00
pcmcia
ras
rdma IB/mlx4: Enable send of RoCE QP1 packets with IP/UDP headers 2016-01-19 15:35:01 -05:00
rxrpc
scsi Initial roundup of 4.5 merge window patches 2016-01-23 18:45:06 -08:00
soc ARM: SoC driver updates for v4.5 2016-01-20 18:42:30 -08:00
sound ALSA: hda - Loop interrupt handling until really cleared 2016-02-26 08:50:31 +01:00
target target/transport: add flag to indicate CPU Affinity is observed 2016-02-10 23:08:55 -08:00
trace Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-15 13:50:29 -07:00
uapi Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-15 12:13:56 -07:00
video
xen Merge branch 'for-4.5/drivers' of git://git.kernel.dk/linux-block 2016-01-21 18:19:38 -08:00
Kbuild