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

From: Ian Rogers
Date: Thu Aug 24 2023 - 14:02:39 EST


On Thu, Aug 24, 2023 at 7:52 AM Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
>
> 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

Thanks, I'll address the issue (hardcoded assumption on jevents.py
output) and resend the patch.

Ian

> ---- 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 ~]#