kernel-fxtec-pro1x/arch/x86
Cyrill Gorcunov a072738e04 perf, x86: Implement initial P4 PMU driver
The netburst PMU is way different from the "architectural
perfomance monitoring" specification that current CPUs use.
P4 uses a tuple of ESCR+CCCR+COUNTER MSR registers to handle
perfomance monitoring events.

A few implementational details:

1) We need a separate x86_pmu::hw_config helper in struct
   x86_pmu since register bit-fields are quite different from P6,
   Core and later cpu series.

2) For the same reason is a x86_pmu::schedule_events helper
   introduced.

3) hw_perf_event::config consists of packed ESCR+CCCR values.
   It's allowed since in reality both registers only use a half
   of their size. Of course before making a real write into a
   particular MSR we need to unpack the value and extend it to
   a proper size.

4) The tuple of packed ESCR+CCCR in hw_perf_event::config
   doesn't describe the memory address of ESCR MSR register
   so that we need to keep a mapping between these tuples
   used and available ESCR (various P4 events may use same
   ESCRs but not simultaneously), for this sake every active
   event has a per-cpu map of hw_perf_event::idx <--> ESCR
   addresses.

5) Since hw_perf_event::idx is an offset to counter/control register
   we need to lift X86_PMC_MAX_GENERIC up, otherwise kernel
   strips it down to 8 registers and event armed may never be turned
   off (ie the bit in active_mask is set but the loop never reaches
   this index to check), thanks to Peter Zijlstra

Restrictions:

 - No cascaded counters support (do we ever need them?)
 - No dependent events support (so PERF_COUNT_HW_INSTRUCTIONS
   doesn't work for now)
 - There are events with same counters which can't work simultaneously
   (need to use intersected ones due to broken counter 1)
 - No PERF_COUNT_HW_CACHE_ events yet

Todo:

 - Implement dependent events
 - Need proper hashing for event opcodes (no linear search, good for
   debugging stage but not in real loads)
 - Some events counted during a clock cycle -- need to set threshold
   for them and count every clock cycle just to get summary statistics
   (ie to behave the same way as other PMUs do)
 - Need to swicth to use event_constraints
 - To support RAW events we need to encode a global list of P4 events
   into p4_templates
 - Cache events need to be added

Event support status matrix:

 Event			status
 -----------------------------
 cycles			works
 cache-references	works
 cache-misses		works
 branch-misses		works
 bus-cycles		partially (does not work on 64bit cpu with HT enabled)
 instruction		doesnt work (needs dependent event [mop tagging])
 branches		doesnt work

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100311165439.GB5129@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-11 18:51:08 +01:00
..
boot Merge branch 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-02-28 10:43:53 -08:00
configs
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2009-12-01 15:16:22 +08:00
ia32 Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-03-03 08:15:37 -08:00
include/asm perf, x86: Implement initial P4 PMU driver 2010-03-11 18:51:08 +01:00
kernel perf, x86: Implement initial P4 PMU driver 2010-03-11 18:51:08 +01:00
kvm Merge branch 'kvm-updates/2.6.34' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2010-03-05 13:12:34 -08:00
lguest
lib perf, x86: Add INSTRUCTION_DECODER config flag 2010-03-10 13:34:12 +01:00
math-emu
mm Merge branch 'x86-bootmem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-03-03 08:15:05 -08:00
oprofile perf, x86: rename macro in ARCH_PERFMON_EVENTSEL_ENABLE 2010-03-01 14:21:23 +01:00
pci Merge branch 'x86-mrst-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-03-07 15:59:39 -08:00
power
tools x86: Remove trailing spaces in messages 2010-02-07 17:47:51 +01:00
vdso sysctl x86: Remove dead binary sysctl support 2009-11-12 02:05:04 -08:00
video
xen Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-03-03 09:11:02 -08:00
Kbuild
Kconfig perf, x86: Add INSTRUCTION_DECODER config flag 2010-03-10 13:34:12 +01:00
Kconfig.cpu Merge branch 'x86-rwsem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-02-28 10:41:35 -08:00
Kconfig.debug Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-12-11 20:47:30 -08:00
Makefile x86-64: Allow fbdev primary video code 2010-02-16 21:22:26 -08:00
Makefile_32.cpu Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-12-08 13:38:11 -08:00