Re: [PATCH v2 00/18] Lazily load PMU data

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Wed, Aug 23, 2023 at 09:13:12PM -0700, Ian Rogers escreveu:
> Lazily load PMU data both from sysfs and json files. Reorganize
> json data to be more PMU oriented to facilitate this, for
> example, json data is now sorted into arrays for their PMU.
> 
> In refactoring the code some changes were made to get rid of maximum
> encoding sizes for events (256 bytes), with input files being directly
> passed to the lex generated code. There is also a small event parse
> error message improvement.
> 
> Some results from an Intel tigerlake laptop running Debian:
> 
> Binary size reduction of 5.3% or 552,864 bytes because the PMU
> name no longer appears in the string or desc field.
> 
> stat -e cpu/cycles/ minor faults reduced from 1733 to 1667, open calls reduced
> from 171 to 94.
> 
> stat default minor faults reduced from 1805 to 1717, open calls reduced
> from 654 to 343.
> 
> Average PMU scanning reduced from 4720.641usec to 2927.293usec.
> Average core PMU scanning reduced from 1004.658usec to 232.668usec
> (4.3x faster).
> 
> v2: Add error path for failing strdup when allocating a format,
>     suggested by Arnaldo. Rebased on top of tmp.perf-tools-next
>     removing 8 patches. Added "perf jevents: Don't append Unit to
>     desc" to save yet more encoding json event space.

So this is failing here:

[acme@quaco ~]$ perf test 10
 10: PMU events                                 :
 10.1: PMU event table sanity                           : FAILED!
 10.2: PMU event map aliases                            : FAILED!
 10.3: Parsing of PMU event table metrics               : Ok
 10.4: Parsing of PMU event table metrics with fake PMUs: Ok
 10.5: Parsing of metric thresholds with fake PMUs      : Ok
[acme@quaco ~]$

[root@quaco ~]# grep -m1 "model name" /proc/cpuinfo
model name	: Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz
[root@quaco ~]# 


[root@quaco ~]# perf test -vv -F 10 |& head -40
 10: PMU events                                                      :
 10.1: PMU event table sanity                                        :
--- start ---
testing event table bp_l1_btb_correct: pass
testing event table bp_l2_btb_correct: pass
testing event table dispatch_blocked.any: pass
testing event table eist_trans: pass
testing event table l3_cache_rd: pass
testing event table segment_reg_loads.any: pass
testing event e1 uncore_hisi_ddrc.flux_wcmd: mismatched desc, DDRC write commands vs DDRC write commands. Unit: hisi_sccl,ddrc


Strange:

        if (!is_same(e1->desc, e2->desc)) {
                pr_debug2("testing event e1 %s: mismatched desc, %s vs %s\n",
                          e1->name, e1->desc, e2->desc);
                return -1;
        }

Adding "" around those descs:

testing event e1 uncore_hisi_ddrc.flux_wcmd: mismatched desc, "DDRC write commands" vs "DDRC write commands. Unit: hisi_sccl,ddrc"

I see, its the last patch, removing it the tests passes, please take a
look at tmp.perf-tools-next

- Arnaldo



---- end ----
PMU events subtest 1: FAILED!
 10.2: PMU event map aliases                                         :
--- start ---
Using CPUID GenuineIntel-6-8E-A
testing aliases core PMU cpu: matched event bp_l1_btb_correct
testing aliases core PMU cpu: matched event bp_l2_btb_correct
testing aliases core PMU cpu: matched event segment_reg_loads.any
testing aliases core PMU cpu: matched event dispatch_blocked.any
testing aliases core PMU cpu: matched event eist_trans
testing aliases core PMU cpu: matched event l3_cache_rd
testing core PMU cpu aliases: pass
testing aliases PMU hisi_sccl1_ddrc2: mismatched desc, DDRC write commands vs DDRC write commands. Unit: hisi_sccl,ddrc
testing aliases uncore PMU hisi_sccl1_ddrc2: could not match alias uncore_hisi_ddrc.flux_wcmd
---- end ----
PMU events subtest 2: FAILED!
 10.3: Parsing of PMU event table metrics                            :
--- start ---
Found metric 'CPI'
metric expr 1 / IPC for CPI
parsing metric: 1 / IPC
metric expr inst_retired.any / cpu_clk_unhalted.thread for IPC
parsing metric: inst_retired.any / cpu_clk_unhalted.thread
found event inst_retired.any
found event cpu_clk_unhalted.thread
Parsing metric events '{inst_retired.any/metric-id=inst_retired.any/,cpu_clk_unhalted.thread/metric-id=cpu_clk_unhalted.thread/}:W'
Attempting to add event pmu 'inst_retired.any' with '(null),' that may result in non-fatal errors
After aliases, add event pmu 'inst_retired.any' with '(null),' that may result in non-fatal errors
Attempting to add event pmu 'cpu_clk_unhalted.thread' with '(null),' that may result in non-fatal errors
After aliases, add event pmu 'cpu_clk_unhalted.thread' with '(null),' that may result in non-fatal errors
[root@quaco ~]#

Trying on a AMD 5950x:

[root@five ~]# perf test -F -vv 10 |& head -40
 10: PMU events                                                      :
 10.1: PMU event table sanity                                        :
--- start ---
testing event table bp_l1_btb_correct: pass
testing event table bp_l2_btb_correct: pass
testing event table dispatch_blocked.any: pass
testing event table eist_trans: pass
testing event table l3_cache_rd: pass
testing event table segment_reg_loads.any: pass
testing event e1 uncore_hisi_ddrc.flux_wcmd: mismatched desc, DDRC write commands vs DDRC write commands. Unit: hisi_sccl,ddrc
---- end ----
PMU events subtest 1: FAILED!
 10.2: PMU event map aliases                                         :
--- start ---
Using CPUID AuthenticAMD-25-21-0
testing aliases core PMU cpu: matched event bp_l1_btb_correct
testing aliases core PMU cpu: matched event bp_l2_btb_correct
testing aliases core PMU cpu: matched event segment_reg_loads.any
testing aliases core PMU cpu: matched event dispatch_blocked.any
testing aliases core PMU cpu: matched event eist_trans
testing aliases core PMU cpu: matched event l3_cache_rd
testing core PMU cpu aliases: pass
testing aliases PMU hisi_sccl1_ddrc2: mismatched desc, DDRC write commands vs DDRC write commands. Unit: hisi_sccl,ddrc
testing aliases uncore PMU hisi_sccl1_ddrc2: could not match alias uncore_hisi_ddrc.flux_wcmd
---- end ----
PMU events subtest 2: FAILED!
 10.3: Parsing of PMU event table metrics                            :
--- start ---
Found metric 'CPI'
metric expr 1 / IPC for CPI
parsing metric: 1 / IPC
metric expr inst_retired.any / cpu_clk_unhalted.thread for IPC
parsing metric: inst_retired.any / cpu_clk_unhalted.thread
found event inst_retired.any
found event cpu_clk_unhalted.thread
Parsing metric events '{inst_retired.any/metric-id=inst_retired.any/,cpu_clk_unhalted.thread/metric-id=cpu_clk_unhalted.thread/}:W'
Attempting to add event pmu 'inst_retired.any' with '(null),' that may result in non-fatal errors
After aliases, add event pmu 'inst_retired.any' with '(null),' that may result in non-fatal errors
Attempting to add event pmu 'cpu_clk_unhalted.thread' with '(null),' that may result in non-fatal errors
After aliases, add event pmu 'cpu_clk_unhalted.thread' with '(null),' that may result in non-fatal errors
[root@five ~]#