In previous generation processors, both bus events and direct
events of performance monitoring unit can be individually
programmabled and monitored in PMCs.
But in Power9, L2/L3 bus events are always available as a
"bank" of 4 events. To obtain the counts for any of the
l2/l3 bus events in a given bank, the user will have to
program PMC4 with corresponding l2/l3 bus event for that
bank.
Patch enforce two contraints incase of L2/L3 bus events.
1)Any L2/L3 event when programmed is also expected to program corresponding
PMC4 event from that group.
2)PMC4 event should always been programmed first due to group constraint
logic limitation
For ex. consider these L3 bus events
PM_L3_PF_ON_CHIP_MEM (0x460A0),
PM_L3_PF_MISS_L3 (0x160A0),
PM_L3_CO_MEM (0x260A0),
PM_L3_PF_ON_CHIP_CACHE (0x360A0),
1) This is an INVALID group for L3 Bus event monitoring,
since it is missing PMC4 event.
perf stat -e "{r160A0,r260A0,r360A0}" < >
And this is a VALID group for L3 Bus events:
perf stat -e "{r460A0,r160A0,r260A0,r360A0}" < >
2) This is an INVALID group for L3 Bus event monitoring,
since it is missing PMC4 event.
perf stat -e "{r260A0,r360A0}" < >
And this is a VALID group for L3 Bus events:
perf stat -e "{r460A0,r260A0,r360A0}" < >
3) This is an INVALID group for L3 Bus event monitoring,
since it is missing PMC4 event.
perf stat -e "{r360A0}" < >
And this is a VALID group for L3 Bus events:
perf stat -e "{r460A0,r360A0}" < >
Patch here implements group constraint logic suggested by Michael Ellerman.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Raw event code has couple of fields "unit" and "cache" in it, to capture
the "unit" to monitor for a given pmcxsel and cache reload qualifier to
program in MMCR1.
isa207_get_constraint() refers "unit" field to update the MMCRC (L2/L3)
Event bus control fields with "cache" bits of the raw event code.
These are power8 specific and not supported by PowerISA v3.0 pmu. So wrap
the checks to be power8 specific. Also, "cache" bit field is referred to
update MMCR1[16:17] and this check can be power8 specific.
Fixes: 7ffd948fae ('powerpc/perf: factor out power8 pmu functions')
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
POWER9 DD1 was never a product. It is no longer supported by upstream
firmware, and it is not effectively supported in Linux due to lack of
testing.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
[mpe: Remove arch_make_huge_pte() entirely]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Comment explanning the raw event code encoding for Power8 was
moved to isa207_common.h file when re-factoring the code to
support power9. But then Power9 pmu branched out due to changes
specific to power9. So move the encoding comment back to power8-pmu.c
Just comment movement and no logic change.
Fixes: 4d3576b207 ('powerpc/perf: factor out power8 pmu macros and defines')
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There are some hardware events on Power systems which only count when
the processor is not idle, and there are some fixed-function counters
which count such events. For example, the "run cycles" event counts
cycles when the processor is not idle. If the user asks to count
cycles, we can use "run cycles" if this is a per-task event, since the
processor is running when the task is running, by definition. We can't
use "run cycles" if the user asks for "cycles" on a system-wide
counter.
Currently in power8 this check is done using PPMU_ONLY_COUNT_RUN flag
in power8_get_alternatives() function. Based on the flag, events are
switched if needed. This function should also be enabled in power9, so
factor out the code to isa207_get_alternatives().
Fixes: efe881afdd ('powerpc/perf: Factor out event_alternative function')
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit 20dd4c624d ('powerpc/perf: Fix SDAR_MODE value for continous
sampling on Power9') set the default sdar_mode value in MMCRA[SDAR_MODE]
to be used as 0b01 (Update on TLB miss). And this value is set if sdar_mode
from event is zero, or we are in continous sampling mode in power9 dd1.
But it is preferred to have the sdar_mode value for power9 as
0b10 (Update on dcache miss) for better sampling updates instead
of 0b01 (Update on TLB miss).
From Anton:
Using a bandwidth test case with a 1MB footprint, I profiled cycles and
chose TLB updates of the SDAR:
$ perf record -d -e r000400000000001E:u ./bw2001 1M
^
SDAR TLB
$ perf report -D | grep PERF_RECORD_SAMPLE | sed 's/.*addr: //' | sort -u | wc -l
4
I get 4 unique addresses. If I ran with dcache misses:
$ perf record -d -e r000800000000001E:u ./bw2001 1M
^
SDAR dcache miss
$ perf report -D|grep PERF_RECORD_SAMPLE| sed 's/.*addr: //'|sort -u | wc -l
5217
I get 5217 unique addresses. No surprises here, but it does show why
TLB misses is the wrong event to default to - we get very little useful
information out of it.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Acked-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Threshold feature when used with MMCRA [Threshold Event Counter Event],
MMCRA[Threshold Start event] and MMCRA[Threshold End event] will update
MMCRA[Threashold Event Counter Exponent] and MMCRA[Threshold Event
Counter Multiplier] with the corresponding threshold event count values.
Patch to export MMCRA[TECX/TECM] to userspace in 'weight' field of
struct perf_sample_data.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The LDST field and DATA_SRC in SIER identifies the memory hierarchy level
(eg: L1, L2 etc), from which a data-cache miss for a marked instruction
was satisfied. Use the 'perf_mem_data_src' object to export this
hierarchy level to user space.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
MMCRA[SDAR_MODE] specifices how the SDAR should be updated in
continous sampling mode. On P9 it must be set to 0b00 when
MMCRA[63] is set.
Fixes: c7c3f568be ('powerpc/perf: macros for power9 format encoding')
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
PMC5 on POWER9 DD1 may not provide right counts in all
sampling scenarios, hence use PM_INST_DISP event instead
in PMC2 or PMC3 in preference.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Factor out the power8 event_alternative function to share
the code with power9.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Patch to add macros and contants to support the power9 raw
event encoding format. Couple of functions added since some of the
bits fields like PMCxCOMB and THRESH_CMP has different width and location
within MMCR* in power9.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Factor out some of the power8 pmu functions
to new file "isa207-common.c" to share with
power9 pmu code. Only code movement and no
logic change
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Factor out some of the power8 pmu macros to
new a header file to share with power9 pmu code.
Just code movement and no logic change.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
