Linux-Scheduler: sched_wakeup auf einer aktiven Aufgabe

Ich versuche, den Linux-Scheduler mit Lttng durch die Verfolgung der Ereignisse sched_wakeup und sched_switch im Kernel 4.4 (Ubuntu 16.04 LTS) zu verfolgen. Manchmal bekomme ich das Ereignis sched_wakeup, noch bevor der Thread aus ist. Ich verstehe die Bedeutung dieses Aufweckens nicht, da der Thread bereits läuft. Das folgende ist ein Stück resultierenden babeltrace Protokoll, das dieses Verhalten zeigt (tid = 2326 wurden die Ereignisse mit Pfeilen markiert):Linux-Scheduler: sched_wakeup auf einer aktiven Aufgabe

-->[15:22:39.515333895] (+0.000001956) usr-VirtualBox sched_switch: { cpu_id = 1 }, { vtid = 2342, procname = "test" }, { prev_comm = "test", prev_tid = 2342, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2326, next_prio = -11 } 
    [15:22:39.515374982] (+0.000001397) usr-VirtualBox sched_switch: { cpu_id = 0 }, { vtid = 2323, procname = "test" }, { prev_comm = "test", prev_tid = 2323, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2328, next_prio = -11 } 
    [15:22:39.515376100] (+0.000001118) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 1 }, { vtid = 2326, procname = "test" }, { rqtp = 140003026402816 } 
    [15:22:39.515378336] (+0.000002236) usr-VirtualBox syscall_exit_nanosleep: { cpu_id = 0 }, { vtid = 2328, procname = "test" }, { ret = 0, rmtp = 140003009617392 } 
-->[15:22:39.515413833] (+0.000003074) usr-VirtualBox sched_wakeup: { cpu_id = 1 }, { vtid = 2326, procname = "test" }, { comm = "test", tid = 2326, prio = -11, target_cpu = 1 } 
    [15:22:39.515418026] (+0.000002516) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 0 }, { vtid = 2328, procname = "test" }, { rqtp = 140003009617408 } 
    [15:22:39.515425293] (+0.000007267) usr-VirtualBox sched_switch: { cpu_id = 0 }, { vtid = 2328, procname = "test" }, { prev_comm = "test", prev_tid = 2328, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2334, next_prio = -11 } 
    [15:22:39.515428088] (+0.000002795) usr-VirtualBox syscall_exit_nanosleep: { cpu_id = 0 }, { vtid = 2334, procname = "test" }, { ret = 0, rmtp = 140002959261168 } 
    [15:22:39.515428647] (+0.000000559) usr-VirtualBox syscall_exit_nanosleep: { cpu_id = 1 }, { vtid = 2326, procname = "test" }, { ret = 0, rmtp = 140003026402800 } 
    [15:22:39.515468616] (+0.000000838) usr-VirtualBox sched_wakeup: { cpu_id = 0 }, { vtid = 2334, procname = "test" }, { comm = "test", tid = 2336, prio = -11, target_cpu = 0 } 
    [15:22:39.515475045] (+0.000002516) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 1 }, { vtid = 2326, procname = "test" }, { rqtp = 140003026402816 } 
    [15:22:39.515482592] (+0.000007547) usr-VirtualBox syscall_entry_clock_gettime: { cpu_id = 0 }, { vtid = 2334, procname = "test" }, { which_clock = 1 } 
-->[15:22:39.515483430] (+0.000000838) usr-VirtualBox sched_switch: { cpu_id = 1 }, { vtid = 2326, procname = "test" }, { prev_comm = "test", prev_tid = 2326, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2325, next_prio = -11 }

Weiß jemand, was das Wake-up tut? Muss ich weitere Informationen liefern?

Bearbeiten: Hinzufügen von zusätzlichen Informationen sowie ein neues Protokoll mit mehr Ereignissen.

Thread 2348 ist geplant mit SCHED_RR auf Priorität 10. Die Zeitscheibe für RR ist der Standard-Vaulue (100ms denke ich). Das System wird stark vom Design überlastet, um die RT-scheduler zu testen, die insgesamt 53 Threads ausführt, die alle unter Verwendung von SCHED_RR geplant werden.

[09:11:06.284125458] (+0.000001957) usr-VirtualBox sched_waking: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { comm = "test", tid = 2348, prio = -11, target_cpu = 0 } 
    [09:11:06.284130489] (+0.000001957) usr-VirtualBox sched_wakeup: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { comm = "test", tid = 2348, prio = -11, target_cpu = 0 } 
    [09:11:06.284133004] (+0.000002515) usr-VirtualBox timer_hrtimer_expire_exit: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88 } 
    [09:11:06.284203160] (+0.000003354) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { rqtp = 140046423100928 } 
    [09:11:06.284206234] (+0.000003074) usr-VirtualBox timer_hrtimer_init: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88, clockid = 1, mode = 1 } 
    [09:11:06.284210707] (+0.000004473) usr-VirtualBox timer_hrtimer_start: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88, function = 0xFFFFFFFF810EED30, expires = 91708656312, softexpires = 91708656312 } 
    [09:11:06.284225800] (+0.000011460) usr-VirtualBox sched_switch: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { prev_comm = "test", prev_tid = 2347, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2348, next_prio = -11 } 
    [09:11:06.284270241] (+0.000002516) usr-VirtualBox timer_hrtimer_cancel: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88 } 
    [09:11:06.284273036] (+0.000000279) usr-VirtualBox timer_hrtimer_expire_entry: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88, now = 91708703021, function = 0xFFFFFFFF810EED30 } 
    [09:11:06.284276390] (+0.000000838) usr-VirtualBox sched_waking: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { comm = "test", tid = 2347, prio = -11, target_cpu = 0 } 
    [09:11:06.284281421] (+0.000005031) usr-VirtualBox sched_wakeup: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { comm = "test", tid = 2347, prio = -11, target_cpu = 0 } 
    [09:11:06.284285334] (+0.000003913) usr-VirtualBox timer_hrtimer_expire_exit: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88 } 
    [09:11:06.284299310] (+0.000002796) usr-VirtualBox syscall_exit_nanosleep: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { ret = 0, rmtp = 140046414708208 } 
    [09:11:06.284365832] (+0.000002516) usr-VirtualBox timer_hrtimer_cancel: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF88001969BE88 } 
    [09:11:06.284369745] (+0.000003075) usr-VirtualBox timer_hrtimer_expire_entry: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF88001969BE88, now = 91708799171, function = 0xFFFFFFFF810EED30 } 
    [09:11:06.284372260] (+0.000000559) usr-VirtualBox sched_waking: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { comm = "test", tid = 2319, prio = -11, target_cpu = 0 } 
    [09:11:06.284375055] (+0.000000559) usr-VirtualBox sched_wakeup: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { comm = "test", tid = 2319, prio = -11, target_cpu = 0 } 
    [09:11:06.284385956] (+0.000010901) usr-VirtualBox timer_hrtimer_expire_exit: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF88001969BE88 } 
    [09:11:06.284406360] (+0.000001118) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { rqtp = 140046414708224 } 
    [09:11:06.284408875] (+0.000000838) usr-VirtualBox timer_hrtimer_init: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88, clockid = 1, mode = 1 } 
    [09:11:06.284413627] (+0.000004752) usr-VirtualBox timer_hrtimer_start: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88, function = 0xFFFFFFFF810EED30, expires = 91708869016, softexpires = 91708869016 } 
    [09:11:06.284431795] (+0.000003634) usr-VirtualBox sched_switch: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { prev_comm = "test", prev_tid = 2348, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2347, next_prio = -11 } 
    [09:11:06.284437105] (+0.000002795) usr-VirtualBox syscall_exit_nanosleep: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { ret = 0, rmtp = 140046423100912 } 
    [09:11:06.284456950] (+0.000019845) usr-VirtualBox timer_hrtimer_cancel: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88 } 
    [09:11:06.284459745] (+0.000001956) usr-VirtualBox timer_hrtimer_expire_entry: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88, now = 91708890569, function = 0xFFFFFFFF810EED30 } 
    [09:11:06.284462540] (+0.000001956) usr-VirtualBox sched_waking: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { comm = "test", tid = 2348, prio = -11, target_cpu = 0 } 
    [09:11:06.284467292] (+0.000003913) usr-VirtualBox sched_wakeup: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { comm = "test", tid = 2348, prio = -11, target_cpu = 0 } 
    [09:11:06.284470087] (+0.000001957) usr-VirtualBox timer_hrtimer_expire_exit: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88 } 
    [09:11:06.284535212] (+0.000001118) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { rqtp = 140046423100928 } 
    [09:11:06.284537727] (+0.000000838) usr-VirtualBox timer_hrtimer_init: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88, clockid = 1, mode = 1 } 
    [09:11:06.284542479] (+0.000004752) usr-VirtualBox timer_hrtimer_start: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88, function = 0xFFFFFFFF810EED30, expires = 91708993675, softexpires = 91708993675 } 
    [09:11:06.284559528] (+0.000002795) usr-VirtualBox sched_switch: { cpu_id = 0 }, { vtid = 2347, procname = "test" }, { prev_comm = "test", prev_tid = 2347, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2319, next_prio = -11 } 
    [09:11:06.284579094] (+0.000002236) usr-VirtualBox timer_hrtimer_cancel: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88 } 
    [09:11:06.284582727] (+0.000003354) usr-VirtualBox timer_hrtimer_expire_entry: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88, now = 91709012433, function = 0xFFFFFFFF810EED30 } 
    [09:11:06.284585243] (+0.000000559) usr-VirtualBox sched_waking: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { comm = "test", tid = 2347, prio = -11, target_cpu = 0 } 
    [09:11:06.284590833] (+0.000000559) usr-VirtualBox sched_wakeup: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { comm = "test", tid = 2347, prio = -11, target_cpu = 0 } 
    [09:11:06.284593628] (+0.000002795) usr-VirtualBox timer_hrtimer_expire_exit: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { hrtimer = 0xFFFF8800256E7E88 } 
    [09:11:06.284607324] (+0.000003075) usr-VirtualBox syscall_exit_nanosleep: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { ret = 0, rmtp = 140046658096624 } 
    [09:11:06.284649529] (+0.000001956) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { rqtp = 140046658096640 } 
    [09:11:06.284652045] (+0.000002516) usr-VirtualBox timer_hrtimer_init: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { hrtimer = 0xFFFF88001969BE88, clockid = 1, mode = 1 } 
    [09:11:06.284656796] (+0.000001118) usr-VirtualBox timer_hrtimer_start: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { hrtimer = 0xFFFF88001969BE88, function = 0xFFFFFFFF810EED30, expires = 91709780826, softexpires = 91709780826 } 
-->[09:11:06.284673007] (+0.000001118) usr-VirtualBox sched_switch: { cpu_id = 0 }, { vtid = 2319, procname = "test" }, { prev_comm = "test", prev_tid = 2319, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2348, next_prio = -11 } 
    [09:11:06.284678318] (+0.000003634) usr-VirtualBox syscall_exit_nanosleep: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { ret = 0, rmtp = 140046414708208 } 
    [09:11:06.284746238] (+0.000002516) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { rqtp = 140046414708224 } 
    [09:11:06.284749033] (+0.000001398) usr-VirtualBox timer_hrtimer_init: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88, clockid = 1, mode = 1 } 
    [09:11:06.284753784] (+0.000001397) usr-VirtualBox timer_hrtimer_start: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88, function = 0xFFFFFFFF810EED30, expires = 91709190725, softexpires = 91709190725 } 
    [09:11:06.284800182] (+0.000036615) usr-VirtualBox timer_hrtimer_cancel: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88 } 
    [09:11:06.284803257] (+0.000002795) usr-VirtualBox timer_hrtimer_expire_entry: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88, now = 91709233521, function = 0xFFFFFFFF810EED30 } 
    [09:11:06.284806331] (+0.000002236) usr-VirtualBox sched_waking: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { comm = "test", tid = 2348, prio = -11, target_cpu = 0 } 
-->[09:11:06.284811921] (+0.000005031) usr-VirtualBox sched_wakeup: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { comm = "test", tid = 2348, prio = -11, target_cpu = 0 } 
    [09:11:06.284814996] (+0.000002516) usr-VirtualBox timer_hrtimer_expire_exit: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88 } 
    [09:11:06.284834282] (+0.000019007) usr-VirtualBox syscall_exit_nanosleep: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { ret = 0, rmtp = 140046414708208 } 
    [09:11:06.284885990] (+0.000002515) usr-VirtualBox syscall_entry_nanosleep: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { rqtp = 140046414708224 } 
    [09:11:06.284888506] (+0.000002236) usr-VirtualBox timer_hrtimer_init: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88, clockid = 1, mode = 1 } 
    [09:11:06.284893537] (+0.000004752) usr-VirtualBox timer_hrtimer_start: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { hrtimer = 0xFFFF8800256EFE88, function = 0xFFFFFFFF810EED30, expires = 91709347527, softexpires = 91709347527 } 
-->[09:11:06.284915338] (+0.000021522) usr-VirtualBox sched_switch: { cpu_id = 0 }, { vtid = 2348, procname = "test" }, { prev_comm = "test", prev_tid = 2348, prev_prio = -11, prev_state = 1, next_comm = "test", next_tid = 2347, next_prio = -11 }

Quelle

2016-05-03 Cupo

Ich änderte den Titel und formatierte den Ergebnisabschnitt für die richtige Lesbarkeit. Ich habe auch die Keywords in der Hauptfrage hervorgehoben. – zx485

nicht sicher, warum das 2326-Thread nicht nach Eingabe der geplanten Nanosleep aus wurde (vielleicht haben Sie einige RT-Konfiguration), aber da es schläft, kann ein Wake-up wahrscheinlich erreichen.

Sie könnten sched_waking aktivieren (um genau zu wissen, was der Waker ist) und die hrtimer-Ereignisse, um mehr Informationen zu haben.

Quelle

2016-05-05 13:24:11

Danke, ich habe die neuen Ereignisse zum Trace hinzugefügt und erneut ausgeführt. Ich weiß immer noch nicht, warum es sich so verhält. Es sollte ausgeschaltet werden, da das System stark überlastet ist. Ich benutze den RT-Scheduler mit SCHED_RR, ich habe vergessen, das im ursprünglichen Beitrag zu erwähnen. Ich habe den Beitrag bearbeitet und ein neues Protokoll hinzugefügt, das die neuen Ereignisse anzeigt. – Cupo

Linux-Scheduler: sched_wakeup auf einer aktiven Aufgabe

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