Hi, Just tried v3 series. perf-stat works fine. From the IGT tests which I wrote for i915 PMU (https://patchwork.freedesktop.org/series/29313/) all pass (assuming pmu.enabled will be exposed in debugfs) except cpu_online subtest. And this is pretty interesting - see details below. Ok, be prepared for the long mail:)... So, cpu_online subtest loads RCS0 engine 100% and starts to put CPUs offline one by one starting from CPU0 (don't forget to have CONFIG_BOOTPARAM_HOTPLUG_CPU0=y in .config). Test expectation is that i915 PMU will report almost 100% (with 2% tolerance) busyness of RCS0. Test requests metric just twice: before running on RCS0 and right after. This fails as follows: Executed on rcs0 for 32004262184us i915/rcs0-busy/: 2225723999us (perf_pmu:6325) CRITICAL: Test assertion failure function test_cpu_online, file perf_pmu.c:719: (perf_pmu:6325) CRITICAL: Failed assertion: perf_elapsed(&pm.metrics[0]) > (1-USAGE_TOLERANCE) * elapsed_ns(&start, &now) Stack trace: #0 [__igt_fail_assert+0xf1] #1 [__real_main773+0xff1] #2 [main+0x35] #3 [__libc_start_main+0xf5] #4 [_start+0x29] #5 [<unknown>+0x29] Subtest cpu_online failed. **** DEBUG **** (perf_pmu:6325) DEBUG: Test requirement passed: is_hotplug_cpu0() (perf_pmu:6325) INFO: perf_init: enabled 1 metrics from 1 requested (perf_pmu:6325) ioctl-wrappers-DEBUG: Test requirement passed: gem_has_ring(fd, ring) (perf_pmu:6325) INFO: Executed on rcs0 for 32004262184us (perf_pmu:6325) INFO: i915/rcs0-busy/: 2225723999us (perf_pmu:6325) CRITICAL: Test assertion failure function test_cpu_online, file perf_pmu.c:719: (perf_pmu:6325) CRITICAL: Failed assertion: perf_elapsed(&pm.metrics[0]) > (1-USAGE_TOLERANCE) * elapsed_ns(&start, &now) Now. Looks like that by itself PMU context migration works. For example, if you will comment out "perf_pmu_migrate_context(&pmu->base, cpu, target)" you will get: Executed on rcs0 for 32004434918us i915/rcs0-busy/: 76623707us Compare with previous: Executed on rcs0 for 32004262184us i915/rcs0-busy/: 2225723999us This test passed on the previous set of patches, I mean Tvrtko's v2 series + my patches. So, it seems we are loosing counter values somehow. I saw in the patches that this place really was modified - you have added subtraction from initial counter value: static void i915_pmu_event_read(struct perf_event *event) { local64_set(&event->count, __i915_pmu_event_read(event) - local64_read(&event->hw.prev_count)); } But looks like the problem is that with the PMU context migration we get sequence of events start/stop (or maybe add/del) which eventually call our i915_pmu_enable/disable. Here is the dmesg log with the obvious printk: [ 153.971096] [IGT] perf_pmu: starting subtest cpu_online [ 153.971151] i915_pmu_enable: event->hw.prev_count=0 [ 154.036015] i915_pmu_disable: event->hw.prev_count=0 [ 154.048027] i915_pmu_enable: event->hw.prev_count=0 [ 154.049343] smpboot: CPU 0 is now offline [ 155.059028] smpboot: Booting Node 0 Processor 0 APIC 0x0 [ 155.155078] smpboot: CPU 1 is now offline [ 156.161026] x86: Booting SMP configuration: [ 156.161027] smpboot: Booting Node 0 Processor 1 APIC 0x2 [ 156.197065] IRQ 122: no longer affine to CPU2 [ 156.198087] smpboot: CPU 2 is now offline [ 157.208028] smpboot: Booting Node 0 Processor 2 APIC 0x4 [ 157.263093] smpboot: CPU 3 is now offline [ 158.273026] smpboot: Booting Node 0 Processor 3 APIC 0x6 [ 158.310026] i915_pmu_disable: event->hw.prev_count=76648307 [ 158.319020] i915_pmu_enable: event->hw.prev_count=76648307 [ 158.319098] IRQ 124: no longer affine to CPU4 [ 158.320368] smpboot: CPU 4 is now offline [ 159.326030] smpboot: Booting Node 0 Processor 4 APIC 0x1 [ 159.365306] smpboot: CPU 5 is now offline [ 160.371030] smpboot: Booting Node 0 Processor 5 APIC 0x3 [ 160.421077] IRQ 125: no longer affine to CPU6 [ 160.422093] smpboot: CPU 6 is now offline [ 161.429030] smpboot: Booting Node 0 Processor 6 APIC 0x5 [ 161.467091] smpboot: CPU 7 is now offline [ 162.473027] smpboot: Booting Node 0 Processor 7 APIC 0x7 [ 162.527019] i915_pmu_disable: event->hw.prev_count=4347548222 [ 162.546017] i915_pmu_enable: event->hw.prev_count=4347548222 [ 162.547317] smpboot: CPU 0 is now offline [ 163.553028] smpboot: Booting Node 0 Processor 0 APIC 0x0 [ 163.621089] smpboot: CPU 1 is now offline [ 164.627028] x86: Booting SMP configuration: [ 164.627029] smpboot: Booting Node 0 Processor 1 APIC 0x2 [ 164.669308] smpboot: CPU 2 is now offline [ 165.679025] smpboot: Booting Node 0 Processor 2 APIC 0x4 [ 165.717089] smpboot: CPU 3 is now offline [ 166.723025] smpboot: Booting Node 0 Processor 3 APIC 0x6 [ 166.775016] i915_pmu_disable: event->hw.prev_count=8574197312 [ 166.787016] i915_pmu_enable: event->hw.prev_count=8574197312 [ 166.788309] smpboot: CPU 4 is now offline [ 167.794025] smpboot: Booting Node 0 Processor 4 APIC 0x1 [ 167.837114] smpboot: CPU 5 is now offline [ 168.847025] smpboot: Booting Node 0 Processor 5 APIC 0x3 [ 168.889312] smpboot: CPU 6 is now offline [ 169.899030] smpboot: Booting Node 0 Processor 6 APIC 0x5 [ 169.944104] smpboot: CPU 7 is now offline [ 170.954032] smpboot: Booting Node 0 Processor 7 APIC 0x7 [ 171.000016] i915_pmu_disable: event->hw.prev_count=12815138319 [ 171.008017] i915_pmu_enable: event->hw.prev_count=12815138319 [ 171.009304] smpboot: CPU 0 is now offline [ 172.017028] smpboot: Booting Node 0 Processor 0 APIC 0x0 [ 172.096104] smpboot: CPU 1 is now offline [ 173.106025] x86: Booting SMP configuration: [ 173.106026] smpboot: Booting Node 0 Processor 1 APIC 0x2 [ 173.147078] smpboot: CPU 2 is now offline [ 174.153025] smpboot: Booting Node 0 Processor 2 APIC 0x4 [ 174.192093] smpboot: CPU 3 is now offline [ 175.198028] smpboot: Booting Node 0 Processor 3 APIC 0x6 [ 175.229042] i915_pmu_disable: event->hw.prev_count=17035889079 [ 175.242030] i915_pmu_enable: event->hw.prev_count=17035889079 [ 175.242163] IRQ fixup: irq 120 move in progress, old vector 131 [ 175.242165] IRQ fixup: irq 121 move in progress, old vector 147 [ 175.242171] IRQ 124: no longer affine to CPU4 [ 175.243435] smpboot: CPU 4 is now offline [ 176.248040] smpboot: Booting Node 0 Processor 4 APIC 0x1 [ 176.285328] smpboot: CPU 5 is now offline [ 177.296039] smpboot: Booting Node 0 Processor 5 APIC 0x3 [ 177.325067] IRQ 125: no longer affine to CPU6 [ 177.326087] smpboot: CPU 6 is now offline [ 178.335036] smpboot: Booting Node 0 Processor 6 APIC 0x5 [ 178.377063] IRQ 122: no longer affine to CPU7 [ 178.378086] smpboot: CPU 7 is now offline [ 179.388028] smpboot: Booting Node 0 Processor 7 APIC 0x7 [ 179.454030] i915_pmu_disable: event->hw.prev_count=21269856967 [ 179.470026] i915_pmu_enable: event->hw.prev_count=21269856967 [ 179.471110] smpboot: CPU 0 is now offline [ 180.481028] smpboot: Booting Node 0 Processor 0 APIC 0x0 [ 180.551075] smpboot: CPU 1 is now offline [ 181.558029] x86: Booting SMP configuration: [ 181.558030] smpboot: Booting Node 0 Processor 1 APIC 0x2 [ 181.595096] smpboot: CPU 2 is now offline [ 182.605029] smpboot: Booting Node 0 Processor 2 APIC 0x4 [ 182.657084] smpboot: CPU 3 is now offline [ 183.668030] smpboot: Booting Node 0 Processor 3 APIC 0x6 [ 183.709017] i915_pmu_disable: event->hw.prev_count=25497358644 [ 183.727016] i915_pmu_enable: event->hw.prev_count=25497358644 [ 183.728305] smpboot: CPU 4 is now offline [ 184.734027] smpboot: Booting Node 0 Processor 4 APIC 0x1 [ 184.767090] smpboot: CPU 5 is now offline [ 185.777036] smpboot: Booting Node 0 Processor 5 APIC 0x3 [ 185.823096] smpboot: CPU 6 is now offline [ 186.829051] smpboot: Booting Node 0 Processor 6 APIC 0x5 [ 186.856350] smpboot: CPU 7 is now offline [ 187.862051] smpboot: Booting Node 0 Processor 7 APIC 0x7 [ 187.871216] [IGT] perf_pmu: exiting, ret=99 [ 187.889199] Console: switching to colour frame buffer device 240x67 [ 187.889583] i915_pmu_disable: event->hw.prev_count=29754080941 And the result which I got in userspace for this run were Executed on rcs0 for 32003587981us i915/rcs0-busy/: 2247436461us After that I decided to roll back the change with counting values which I mentioned before, i.e.: static void i915_pmu_event_read(struct perf_event *event) { local64_set(&event->count, __i915_pmu_event_read(event) /*- local64_read(&event->hw.prev_count)*/); } And I got test PASSED :): Executed on rcs0 for 32002282603us i915/rcs0-busy/: 31998855052us Subtest cpu_online: SUCCESS (33.950s) At this point I need to go home :). Maybe you will have time to look into this issue? If not, I will continue tomorrow. Regards, Dmitry. _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
