> Stefan Wahren <stefan.wahren@xxxxxxxx> hat am 22. April 2017 um 22:50 geschrieben: > > > Hi, > > > Eric Anholt <eric@xxxxxxxxxx> hat am 20. April 2017 um 20:54 geschrieben: > > > > > > Stefan Wahren <stefan.wahren@xxxxxxxx> writes: > > > > > Hi, > > > > > >> Doug Anderson <dianders@xxxxxxxxxxxx> hat am 18. April 2017 um 22:41 geschrieben: > > >> > > >> > > >> It's hard to know for sure that all of this time is really in > > >> urb_enqueue(). Possible we could have task switched out and been > > >> blocked elsewhere. Using ftrace to get more fine-grained timings > > >> would be useful. ktime_get(), ktime_sub(), and ktime_to_us() are your > > >> friends here if you want to use trace_printk. > > > > > > i'm a newbie to ftrace, so i hope this would be helpful. > > > > > > # connect PL2303 to the onboard hub > > > # echo 0 > options/sleep-time > > > # echo 0 > function_profile_enabled > > > # echo 1 > function_profile_enabled > > > # ./usb_test > > > # Waiting for at least 20 seconds and then disconnect PL2303 > > > # echo 0 > function_profile_enabled > > > # cat trace_stat/function0 > > > > > > Function Hit Time Avg s^2 > > > -------- --- ---- --- --- > > > bcm2835_handle_irq 361347 219567633 us 607.636 us 1485199 us > > > __handle_domain_irq 1082482 212639551 us 196.437 us 3642030 us > > > generic_handle_irq 1082482 100592051 us 92.927 us 50511334 us > > > irq_exit 1082482 98197771 us 90.715 us 29649040 us > > > handle_level_irq 1082482 95812379 us 88.511 us 51910093 us > > > > If I'm reading this output right, we're spending half of our interrupt > > processing time in irq_exit(), so even if dwc2's interrupt was free (the > > generic_handle_irq() chain), we'd be eating about half the CPU getting > > back out of the interrupt handler, right? > > > > I don't really know anything about DWC2 or USB, but is there any way we > > could mitigate the interrupt frequency with this hardware? If nothing > > else, could we loop reading gintsts until it reads back 0? > > first of all i updated my kernel to 4.11rc7 and the issue still occures. Today i had some time to investigate this issue further and i made some interesting observations: > > 1. The lockup doesn't occure always after starting usb_test. In rare cases i was able to run the program without lockup. > 2. In case the lockup occured we are always able to "rescue" the BCM2835 from this state by sending some serial data to the PL2303. Based on this scenario i patched the interrupt routine to detect the interrupt storm and normal condition. So i can dump the global and host registers in both situations (bad and goodcase). Here is the diff between both register dumps, maybe someone see something interesting: --- badcase.txt 2017-04-25 18:02:59.000000000 +0000 +++ goodcase.txt 2017-04-25 18:02:59.000000000 +0000 @@ -4,12 +4,12 @@ dwc2_dump_global_registers: GAHBCFG @0xCC850008 : 0x00000031 dwc2_dump_global_registers: GUSBCFG @0xCC85000C : 0x20001700 dwc2_dump_global_registers: GRSTCTL @0xCC850010 : 0x80000000 - dwc2_dump_global_registers: GINTSTS @0xCC850014 : 0x06000021 + dwc2_dump_global_registers: GINTSTS @0xCC850014 : 0x06000029 dwc2_dump_global_registers: GINTMSK @0xCC850018 : 0xF300080E - dwc2_dump_global_registers: GRXSTSR @0xCC85001C : 0x00070044 + dwc2_dump_global_registers: GRXSTSR @0xCC85001C : 0x000F0001 dwc2_dump_global_registers: GRXFSIZ @0xCC850024 : 0x00000306 dwc2_dump_global_registers: GNPTXFSIZ @0xCC850028 : 0x01000306 - dwc2_dump_global_registers: GNPTXSTS @0xCC85002C : 0x1D080100 + dwc2_dump_global_registers: GNPTXSTS @0xCC85002C : 0x18080100 dwc2_dump_global_registers: GI2CCTL @0xCC850030 : 0x00000000 dwc2_dump_global_registers: GPVNDCTL @0xCC850034 : 0x00000000 dwc2_dump_global_registers: GGPIO @0xCC850038 : 0x00000000 @@ -27,64 +27,64 @@ dwc2_dump_host_registers: Host Global Registers dwc2_dump_host_registers: HCFG @0xCC850400 : 0x00000000 dwc2_dump_host_registers: HFIR @0xCC850404 : 0x00001D4B - dwc2_dump_host_registers: HFNUM @0xCC850408 : 0x0BF03CA1 - dwc2_dump_host_registers: HPTXSTS @0xCC850410 : 0x29080200 - dwc2_dump_host_registers: HAINT @0xCC850414 : 0x00000002 - dwc2_dump_host_registers: HAINTMSK @0xCC850418 : 0x00000002 + dwc2_dump_host_registers: HFNUM @0xCC850408 : 0x029F3421 + dwc2_dump_host_registers: HPTXSTS @0xCC850410 : 0x25080200 + dwc2_dump_host_registers: HAINT @0xCC850414 : 0x00000001 + dwc2_dump_host_registers: HAINTMSK @0xCC850418 : 0x00000001 dwc2_dump_host_registers: HPRT0 @0xCC850440 : 0x00001005 dwc2_dump_host_registers: Host Channel 0 Specific Registers - dwc2_dump_host_registers: HCCHAR @0xCC850500 : 0x01189840 - dwc2_dump_host_registers: HCSPLT @0xCC850504 : 0x8001C102 - dwc2_dump_host_registers: HCINT @0xCC850508 : 0x00000000 - dwc2_dump_host_registers: HCINTMSK @0xCC85050C : 0x00000000 - dwc2_dump_host_registers: HCTSIZ @0xCC850510 : 0x00080040 - dwc2_dump_host_registers: HCDMA @0xCC850514 : 0x4A07D300 + dwc2_dump_host_registers: HCCHAR @0xCC850500 : 0x013C880A + dwc2_dump_host_registers: HCSPLT @0xCC850504 : 0x8000C102 + dwc2_dump_host_registers: HCINT @0xCC850508 : 0x00000022 + dwc2_dump_host_registers: HCINTMSK @0xCC85050C : 0x00000006 + dwc2_dump_host_registers: HCTSIZ @0xCC850510 : 0x4008000A + dwc2_dump_host_registers: HCDMA @0xCC850514 : 0x4A093840 dwc2_dump_host_registers: Host Channel 1 Specific Registers dwc2_dump_host_registers: HCCHAR @0xCC850520 : 0x01189840 dwc2_dump_host_registers: HCSPLT @0xCC850524 : 0x8000C102 - dwc2_dump_host_registers: HCINT @0xCC850528 : 0x00000022 - dwc2_dump_host_registers: HCINTMSK @0xCC85052C : 0x00000006 + dwc2_dump_host_registers: HCINT @0xCC850528 : 0x00000000 + dwc2_dump_host_registers: HCINTMSK @0xCC85052C : 0x00000000 dwc2_dump_host_registers: HCTSIZ @0xCC850530 : 0x00080040 - dwc2_dump_host_registers: HCDMA @0xCC850534 : 0x4A07D300 + dwc2_dump_host_registers: HCDMA @0xCC850534 : 0x4A07D500 dwc2_dump_host_registers: Host Channel 2 Specific Registers dwc2_dump_host_registers: HCCHAR @0xCC850540 : 0x01189840 dwc2_dump_host_registers: HCSPLT @0xCC850544 : 0x8001C102 dwc2_dump_host_registers: HCINT @0xCC850548 : 0x00000000 dwc2_dump_host_registers: HCINTMSK @0xCC85054C : 0x00000000 dwc2_dump_host_registers: HCTSIZ @0xCC850550 : 0x00080040 - dwc2_dump_host_registers: HCDMA @0xCC850554 : 0x4A07D300 + dwc2_dump_host_registers: HCDMA @0xCC850554 : 0x4A07D500 dwc2_dump_host_registers: Host Channel 3 Specific Registers - dwc2_dump_host_registers: HCCHAR @0xCC850560 : 0x01189840 - dwc2_dump_host_registers: HCSPLT @0xCC850564 : 0x8001C102 + dwc2_dump_host_registers: HCCHAR @0xCC850560 : 0x00D08040 + dwc2_dump_host_registers: HCSPLT @0xCC850564 : 0x00000000 dwc2_dump_host_registers: HCINT @0xCC850568 : 0x00000000 dwc2_dump_host_registers: HCINTMSK @0xCC85056C : 0x00000000 - dwc2_dump_host_registers: HCTSIZ @0xCC850570 : 0x00080040 - dwc2_dump_host_registers: HCDMA @0xCC850574 : 0x4A07D300 + dwc2_dump_host_registers: HCTSIZ @0xCC850570 : 0x8000003C + dwc2_dump_host_registers: HCDMA @0xCC850574 : 0x4A3B7544 dwc2_dump_host_registers: Host Channel 4 Specific Registers - dwc2_dump_host_registers: HCCHAR @0xCC850580 : 0x01189840 - dwc2_dump_host_registers: HCSPLT @0xCC850584 : 0x8001C102 + dwc2_dump_host_registers: HCCHAR @0xCC850580 : 0x00D00040 + dwc2_dump_host_registers: HCSPLT @0xCC850584 : 0x00000000 dwc2_dump_host_registers: HCINT @0xCC850588 : 0x00000000 dwc2_dump_host_registers: HCINTMSK @0xCC85058C : 0x00000000 - dwc2_dump_host_registers: HCTSIZ @0xCC850590 : 0x00080040 - dwc2_dump_host_registers: HCDMA @0xCC850594 : 0x4A07D300 + dwc2_dump_host_registers: HCTSIZ @0xCC850590 : 0x20000008 + dwc2_dump_host_registers: HCDMA @0xCC850594 : 0x4A3B74C8 dwc2_dump_host_registers: Host Channel 5 Specific Registers dwc2_dump_host_registers: HCCHAR @0xCC8505A0 : 0x01189840 dwc2_dump_host_registers: HCSPLT @0xCC8505A4 : 0x8000C102 dwc2_dump_host_registers: HCINT @0xCC8505A8 : 0x00000000 dwc2_dump_host_registers: HCINTMSK @0xCC8505AC : 0x00000000 dwc2_dump_host_registers: HCTSIZ @0xCC8505B0 : 0x00080040 - dwc2_dump_host_registers: HCDMA @0xCC8505B4 : 0x4A07D300 + dwc2_dump_host_registers: HCDMA @0xCC8505B4 : 0x4A07D500 dwc2_dump_host_registers: Host Channel 6 Specific Registers - dwc2_dump_host_registers: HCCHAR @0xCC8505C0 : 0x01189840 - dwc2_dump_host_registers: HCSPLT @0xCC8505C4 : 0x8001C102 + dwc2_dump_host_registers: HCCHAR @0xCC8505C0 : 0x00D00040 + dwc2_dump_host_registers: HCSPLT @0xCC8505C4 : 0x00000000 dwc2_dump_host_registers: HCINT @0xCC8505C8 : 0x00000000 dwc2_dump_host_registers: HCINTMSK @0xCC8505CC : 0x00000000 - dwc2_dump_host_registers: HCTSIZ @0xCC8505D0 : 0x00080040 - dwc2_dump_host_registers: HCDMA @0xCC8505D4 : 0x4A07D300 + dwc2_dump_host_registers: HCTSIZ @0xCC8505D0 : 0x00000000 + dwc2_dump_host_registers: HCDMA @0xCC8505D4 : 0x4B080000 dwc2_dump_host_registers: Host Channel 7 Specific Registers - dwc2_dump_host_registers: HCCHAR @0xCC8505E0 : 0x01189840 + dwc2_dump_host_registers: HCCHAR @0xCC8505E0 : 0x013C880A dwc2_dump_host_registers: HCSPLT @0xCC8505E4 : 0x8001C102 dwc2_dump_host_registers: HCINT @0xCC8505E8 : 0x00000000 dwc2_dump_host_registers: HCINTMSK @0xCC8505EC : 0x00000000 - dwc2_dump_host_registers: HCTSIZ @0xCC8505F0 : 0x00080040 - dwc2_dump_host_registers: HCDMA @0xCC8505F4 : 0x4A07D300 + dwc2_dump_host_registers: HCTSIZ @0xCC8505F0 : 0x4008000A + dwc2_dump_host_registers: HCDMA @0xCC8505F4 : 0x4A093840 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
