sched-linux.cpp@ 76452

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1	/* $Id: sched-linux.cpp 69111 2017-10-17 14:26:02Z vboxsync $ */
2	/** @file
3	* IPRT - Scheduling, POSIX.
4	*/
5
6	/*
7	* Copyright (C) 2006-2017 Oracle Corporation
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*
17	* The contents of this file may alternatively be used under the terms
18	* of the Common Development and Distribution License Version 1.0
19	* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20	* VirtualBox OSE distribution, in which case the provisions of the
21	* CDDL are applicable instead of those of the GPL.
22	*
23	* You may elect to license modified versions of this file under the
24	* terms and conditions of either the GPL or the CDDL or both.
25	*/
26
27	/*
28	* !WARNING!
29	*
30	* When talking about lowering and raising priority, we do NOT refer to
31	* the common direction priority values takes on unix systems (lower means
32	* higher). So, when we raise the priority of a linux thread the nice
33	* value will decrease, and when we lower the priority the nice value
34	* will increase. Confusing, right?
35	*
36	* !WARNING!
37	*/
38
39
40
41	/** @def THREAD_LOGGING
42	* Be very careful with enabling this, it may cause deadlocks when combined
43	* with the 'thread' logging prefix.
44	*/
45	#ifdef DOXYGEN_RUNNING
46	# define THREAD_LOGGING
47	#endif
48
49
50	/*********************************************************************************************************************************
51	* Header Files *
52	*********************************************************************************************************************************/
53	#define LOG_GROUP RTLOGGROUP_THREAD
54	#include <errno.h>
55	#include <pthread.h>
56	#include <sched.h>
57	#include <unistd.h>
58	#include <sys/resource.h>
59
60	#include <iprt/thread.h>
61	#include <iprt/process.h>
62	#include <iprt/semaphore.h>
63	#include <iprt/string.h>
64	#include <iprt/assert.h>
65	#include <iprt/log.h>
66	#include <iprt/err.h>
67	#include "internal/sched.h"
68	#include "internal/thread.h"
69
70
71	/*********************************************************************************************************************************
72	* Structures and Typedefs *
73	*********************************************************************************************************************************/
74
75	/** Array scheduler attributes corresponding to each of the thread types.
76	* @internal */
77	typedef struct PROCPRIORITYTYPE
78	{
79	/** For sanity include the array index. */
80	RTTHREADTYPE enmType;
81	/** The thread priority or nice delta - depends on which priority type. */
82	int iPriority;
83	} PROCPRIORITYTYPE;
84
85
86	/**
87	* Configuration of one priority.
88	* @internal
89	*/
90	typedef struct
91	{
92	/** The priority. */
93	RTPROCPRIORITY enmPriority;
94	/** The name of this priority. */
95	const char *pszName;
96	/** The process nice value. */
97	int iNice;
98	/** The delta applied to the iPriority value. */
99	int iDelta;
100	/** Array scheduler attributes corresponding to each of the thread types. */
101	const PROCPRIORITYTYPE *paTypes;
102	} PROCPRIORITY;
103
104
105	/**
106	* Saved priority settings
107	* @internal
108	*/
109	typedef struct
110	{
111	/** Process priority. */
112	int iPriority;
113	/** Process level. */
114	struct sched_param SchedParam;
115	/** Process level. */
116	int iPolicy;
117	/** pthread level. */
118	struct sched_param PthreadSchedParam;
119	/** pthread level. */
120	int iPthreadPolicy;
121	} SAVEDPRIORITY, *PSAVEDPRIORITY;
122
123
124	/*********************************************************************************************************************************
125	* Global Variables *
126	*********************************************************************************************************************************/
127	/**
128	* Deltas for a process in which we are not restricted
129	* to only be lowering the priority.
130	*/
131	static const PROCPRIORITYTYPE g_aTypesLinuxFree[RTTHREADTYPE_END] =
132	{
133	{ RTTHREADTYPE_INVALID, -999999999 },
134	{ RTTHREADTYPE_INFREQUENT_POLLER, +3 },
135	{ RTTHREADTYPE_MAIN_HEAVY_WORKER, +2 },
136	{ RTTHREADTYPE_EMULATION, +1 },
137	{ RTTHREADTYPE_DEFAULT, 0 },
138	{ RTTHREADTYPE_GUI, 0 },
139	{ RTTHREADTYPE_MAIN_WORKER, 0 },
140	{ RTTHREADTYPE_VRDP_IO, -1 },
141	{ RTTHREADTYPE_DEBUGGER, -1 },
142	{ RTTHREADTYPE_MSG_PUMP, -2 },
143	{ RTTHREADTYPE_IO, -3 },
144	{ RTTHREADTYPE_TIMER, -4 }
145	};
146
147	/**
148	* Deltas for a process in which we are restricted and can only lower the priority.
149	*/
150	static const PROCPRIORITYTYPE g_aTypesLinuxRestricted[RTTHREADTYPE_END] =
151	{
152	{ RTTHREADTYPE_INVALID, -999999999 },
153	{ RTTHREADTYPE_INFREQUENT_POLLER, +3 },
154	{ RTTHREADTYPE_MAIN_HEAVY_WORKER, +2 },
155	{ RTTHREADTYPE_EMULATION, +1 },
156	{ RTTHREADTYPE_DEFAULT, 0 },
157	{ RTTHREADTYPE_GUI, 0 },
158	{ RTTHREADTYPE_MAIN_WORKER, 0 },
159	{ RTTHREADTYPE_VRDP_IO, 0 },
160	{ RTTHREADTYPE_DEBUGGER, 0 },
161	{ RTTHREADTYPE_MSG_PUMP, 0 },
162	{ RTTHREADTYPE_IO, 0 },
163	{ RTTHREADTYPE_TIMER, 0 }
164	};
165
166	/**
167	* All threads have the same priority.
168	*
169	* This is typically chosen when we find that we can't raise the priority
170	* to the process default of a thread created by a low priority thread.
171	*/
172	static const PROCPRIORITYTYPE g_aTypesLinuxFlat[RTTHREADTYPE_END] =
173	{
174	{ RTTHREADTYPE_INVALID, -999999999 },
175	{ RTTHREADTYPE_INFREQUENT_POLLER, 0 },
176	{ RTTHREADTYPE_MAIN_HEAVY_WORKER, 0 },
177	{ RTTHREADTYPE_EMULATION, 0 },
178	{ RTTHREADTYPE_DEFAULT, 0 },
179	{ RTTHREADTYPE_GUI, 0 },
180	{ RTTHREADTYPE_MAIN_WORKER, 0 },
181	{ RTTHREADTYPE_VRDP_IO, 0 },
182	{ RTTHREADTYPE_DEBUGGER, 0 },
183	{ RTTHREADTYPE_MSG_PUMP, 0 },
184	{ RTTHREADTYPE_IO, 0 },
185	{ RTTHREADTYPE_TIMER, 0 }
186	};
187
188	/**
189	* Process and thread level priority, full access at thread level.
190	*/
191	static const PROCPRIORITY g_aUnixConfigs[] =
192	{
193	{ RTPROCPRIORITY_FLAT, "Flat", 0, 0, g_aTypesLinuxFlat },
194	{ RTPROCPRIORITY_LOW, "Low", 9, 9, g_aTypesLinuxFree },
195	{ RTPROCPRIORITY_LOW, "Low", 9, 9, g_aTypesLinuxFlat },
196	{ RTPROCPRIORITY_LOW, "Low", 15, 15, g_aTypesLinuxFree },
197	{ RTPROCPRIORITY_LOW, "Low", 15, 15, g_aTypesLinuxFlat },
198	{ RTPROCPRIORITY_LOW, "Low", 17, 17, g_aTypesLinuxFree },
199	{ RTPROCPRIORITY_LOW, "Low", 17, 17, g_aTypesLinuxFlat },
200	{ RTPROCPRIORITY_LOW, "Low", 19, 19, g_aTypesLinuxFlat },
201	{ RTPROCPRIORITY_LOW, "Low", 9, 9, g_aTypesLinuxRestricted },
202	{ RTPROCPRIORITY_LOW, "Low", 15, 15, g_aTypesLinuxRestricted },
203	{ RTPROCPRIORITY_LOW, "Low", 17, 17, g_aTypesLinuxRestricted },
204	{ RTPROCPRIORITY_NORMAL, "Normal", 0, 0, g_aTypesLinuxFree },
205	{ RTPROCPRIORITY_NORMAL, "Normal", 0, 0, g_aTypesLinuxRestricted },
206	{ RTPROCPRIORITY_NORMAL, "Normal", 0, 0, g_aTypesLinuxFlat },
207	{ RTPROCPRIORITY_HIGH, "High", -9, -9, g_aTypesLinuxFree },
208	{ RTPROCPRIORITY_HIGH, "High", -7, -7, g_aTypesLinuxFree },
209	{ RTPROCPRIORITY_HIGH, "High", -5, -5, g_aTypesLinuxFree },
210	{ RTPROCPRIORITY_HIGH, "High", -3, -3, g_aTypesLinuxFree },
211	{ RTPROCPRIORITY_HIGH, "High", -1, -1, g_aTypesLinuxFree },
212	{ RTPROCPRIORITY_HIGH, "High", -9, -9, g_aTypesLinuxRestricted },
213	{ RTPROCPRIORITY_HIGH, "High", -7, -7, g_aTypesLinuxRestricted },
214	{ RTPROCPRIORITY_HIGH, "High", -5, -5, g_aTypesLinuxRestricted },
215	{ RTPROCPRIORITY_HIGH, "High", -3, -3, g_aTypesLinuxRestricted },
216	{ RTPROCPRIORITY_HIGH, "High", -1, -1, g_aTypesLinuxRestricted },
217	{ RTPROCPRIORITY_HIGH, "High", -9, -9, g_aTypesLinuxFlat },
218	{ RTPROCPRIORITY_HIGH, "High", -7, -7, g_aTypesLinuxFlat },
219	{ RTPROCPRIORITY_HIGH, "High", -5, -5, g_aTypesLinuxFlat },
220	{ RTPROCPRIORITY_HIGH, "High", -3, -3, g_aTypesLinuxFlat },
221	{ RTPROCPRIORITY_HIGH, "High", -1, -1, g_aTypesLinuxFlat }
222	};
223
224	/**
225	* The dynamic default priority configuration.
226	*
227	* This will be recalulated at runtime depending on what the
228	* system allow us to do and what the current priority is.
229	*/
230	static PROCPRIORITY g_aDefaultPriority =
231	{
232	RTPROCPRIORITY_LOW, "Default", 0, 0, g_aTypesLinuxRestricted
233	};
234
235	/** Pointer to the current priority configuration. */
236	static const PROCPRIORITY *g_pProcessPriority = &g_aDefaultPriority;
237
238	/** Set if we can raise the priority of a thread beyond the default.
239	*
240	* It might mean we have the CAP_SYS_NICE capability or that the
241	* process's RLIMIT_NICE is higher than the priority of the thread
242	* calculating the defaults.
243	*/
244	static bool g_fCanRaisePriority = false;
245
246	/** Set if we can restore the priority after having temporarily lowered or raised it. */
247	static bool g_fCanRestorePriority = false;
248
249	/** Set if we can NOT raise the priority to the process default in a thread
250	* created by a thread running below the process default.
251	*/
252	static bool g_fScrewedUpMaxPriorityLimitInheritance = true;
253
254	/** The highest priority we can set. */
255	static int g_iMaxPriority = 0;
256
257	/** The lower priority we can set. */
258	static int g_iMinPriority = 19;
259
260	/** Set when we've successfully determined the capabilities of the process and kernel. */
261	static bool g_fInitialized = false;
262
263
264
265	/*********************************************************************************************************************************
266	* Internal Functions *
267	*********************************************************************************************************************************/
268
269
270	/**
271	* Saves all the scheduling attributes we can think of.
272	*/
273	static void rtSchedNativeSave(PSAVEDPRIORITY pSave)
274	{
275	memset(pSave, 0xff, sizeof(*pSave));
276
277	errno = 0;
278	pSave->iPriority = getpriority(PRIO_PROCESS, 0 /* current process */);
279	Assert(errno == 0);
280
281	errno = 0;
282	sched_getparam(0 /* current process */, &pSave->SchedParam);
283	Assert(errno == 0);
284
285	errno = 0;
286	pSave->iPolicy = sched_getscheduler(0 /* current process */);
287	Assert(errno == 0);
288
289	int rc = pthread_getschedparam(pthread_self(), &pSave->iPthreadPolicy, &pSave->PthreadSchedParam);
290	Assert(rc == 0); NOREF(rc);
291	}
292
293
294	/**
295	* Restores scheduling attributes.
296	* Most of this won't work right, but anyway...
297	*/
298	static void rtSchedNativeRestore(PSAVEDPRIORITY pSave)
299	{
300	setpriority(PRIO_PROCESS, 0, pSave->iPriority);
301	sched_setscheduler(0, pSave->iPolicy, &pSave->SchedParam);
302	sched_setparam(0, &pSave->SchedParam);
303	pthread_setschedparam(pthread_self(), pSave->iPthreadPolicy, &pSave->PthreadSchedParam);
304	}
305
306
307	/**
308	* Starts a worker thread and wait for it to complete.
309	* We cannot use RTThreadCreate since we're already owner of the RW lock.
310	*/
311	static int rtSchedRunThread(void (pfnThread)(void pvArg), void pvArg)
312	{
313	/*
314	* Create the thread.
315	*/
316	pthread_t Thread;
317	int rc = pthread_create(&Thread, NULL, pfnThread, pvArg);
318	if (!rc)
319	{
320	/*
321	* Wait for the thread to finish.
322	*/
323	void pvRet = (void )-1;
324	do
325	{
326	rc = pthread_join(Thread, &pvRet);
327	} while (rc == EINTR);
328	if (rc)
329	return RTErrConvertFromErrno(rc);
330	return (int)(uintptr_t)pvRet;
331	}
332	return RTErrConvertFromErrno(rc);
333	}
334
335
336	static void rtSchedDumpPriority(void)
337	{
338	#ifdef THREAD_LOGGING
339	Log(("Priority: g_fCanRaisePriority=%RTbool g_fCanRestorePriority=%RTbool g_fScrewedUpMaxPriorityLimitInheritance=%RTbool\n",
340	g_fCanRaisePriority, g_fCanRestorePriority, g_fScrewedUpMaxPriorityLimitInheritance));
341	Log(("Priority: g_iMaxPriority=%d g_iMinPriority=%d\n", g_iMaxPriority, g_iMinPriority));
342	Log(("Priority: enmPriority=%d \"%s\" iNice=%d iDelta=%d\n",
343	g_pProcessPriority->enmPriority,
344	g_pProcessPriority->pszName,
345	g_pProcessPriority->iNice,
346	g_pProcessPriority->iDelta));
347	Log(("Priority: %2d INFREQUENT_POLLER = %d\n", RTTHREADTYPE_INFREQUENT_POLLER, g_pProcessPriority->paTypes[RTTHREADTYPE_INFREQUENT_POLLER].iPriority));
348	Log(("Priority: %2d MAIN_HEAVY_WORKER = %d\n", RTTHREADTYPE_MAIN_HEAVY_WORKER, g_pProcessPriority->paTypes[RTTHREADTYPE_MAIN_HEAVY_WORKER].iPriority));
349	Log(("Priority: %2d EMULATION = %d\n", RTTHREADTYPE_EMULATION , g_pProcessPriority->paTypes[RTTHREADTYPE_EMULATION ].iPriority));
350	Log(("Priority: %2d DEFAULT = %d\n", RTTHREADTYPE_DEFAULT , g_pProcessPriority->paTypes[RTTHREADTYPE_DEFAULT ].iPriority));
351	Log(("Priority: %2d GUI = %d\n", RTTHREADTYPE_GUI , g_pProcessPriority->paTypes[RTTHREADTYPE_GUI ].iPriority));
352	Log(("Priority: %2d MAIN_WORKER = %d\n", RTTHREADTYPE_MAIN_WORKER , g_pProcessPriority->paTypes[RTTHREADTYPE_MAIN_WORKER ].iPriority));
353	Log(("Priority: %2d VRDP_IO = %d\n", RTTHREADTYPE_VRDP_IO , g_pProcessPriority->paTypes[RTTHREADTYPE_VRDP_IO ].iPriority));
354	Log(("Priority: %2d DEBUGGER = %d\n", RTTHREADTYPE_DEBUGGER , g_pProcessPriority->paTypes[RTTHREADTYPE_DEBUGGER ].iPriority));
355	Log(("Priority: %2d MSG_PUMP = %d\n", RTTHREADTYPE_MSG_PUMP , g_pProcessPriority->paTypes[RTTHREADTYPE_MSG_PUMP ].iPriority));
356	Log(("Priority: %2d IO = %d\n", RTTHREADTYPE_IO , g_pProcessPriority->paTypes[RTTHREADTYPE_IO ].iPriority));
357	Log(("Priority: %2d TIMER = %d\n", RTTHREADTYPE_TIMER , g_pProcessPriority->paTypes[RTTHREADTYPE_TIMER ].iPriority));
358	#endif
359	}
360
361
362	/**
363	* This just checks if it can raise the priority after having been
364	* created by a thread with a low priority.
365	*
366	* @returns zero on success, non-zero on failure.
367	* @param pvUser The priority of the parent before it was lowered (cast to int).
368	*/
369	static void rtSchedNativeSubProberThread(void pvUser)
370	{
371	int iPriority = getpriority(PRIO_PROCESS, 0);
372	Assert(iPriority == g_iMinPriority);
373
374	if (setpriority(PRIO_PROCESS, 0, iPriority + 1))
375	return (void *)-1;
376	if (setpriority(PRIO_PROCESS, 0, (int)(intptr_t)pvUser))
377	return (void *)-1;
378	return (void *)0;
379	}
380
381
382	/**
383	* The prober thread.
384	* We don't want to mess with the priority of the calling thread.
385	*
386	* @remark This is pretty presumptive stuff, but if it works on Linux and
387	* FreeBSD it does what I want.
388	*/
389	static void rtSchedNativeProberThread(void pvUser)
390	{
391	NOREF(pvUser);
392	SAVEDPRIORITY SavedPriority;
393	rtSchedNativeSave(&SavedPriority);
394
395	/*
396	* Check if we can get higher priority (typically only root can do this).
397	* (Won't work right if our priority is -19 to start with, but what the heck.)
398	*
399	* We assume that the priority range is -19 to 19. Should probably find the right
400	* define for this.
401	*/
402	int iStart = getpriority(PRIO_PROCESS, 0);
403	int i = iStart;
404	while (i-- > -20)
405	if (setpriority(PRIO_PROCESS, 0, i))
406	break;
407	g_iMaxPriority = getpriority(PRIO_PROCESS, 0);
408	g_fCanRaisePriority = g_iMaxPriority < iStart;
409	g_fCanRestorePriority = setpriority(PRIO_PROCESS, 0, iStart) == 0;
410
411	/*
412	* Check if we temporarily lower the thread priority.
413	* Again, we assume we're not at the extreme end of the priority scale.
414	*/
415	iStart = getpriority(PRIO_PROCESS, 0);
416	i = iStart;
417	while (i++ < 19)
418	if (setpriority(PRIO_PROCESS, 0, i))
419	break;
420	g_iMinPriority = getpriority(PRIO_PROCESS, 0);
421	if ( setpriority(PRIO_PROCESS, 0, iStart)
422	\|\| getpriority(PRIO_PROCESS, 0) != iStart)
423	g_fCanRestorePriority = false;
424	if (g_iMinPriority == g_iMaxPriority)
425	g_fCanRestorePriority = g_fCanRaisePriority = false;
426
427	/*
428	* Check what happens to child threads when the parent lowers the
429	* priority when it's being created.
430	*/
431	iStart = getpriority(PRIO_PROCESS, 0);
432	g_fScrewedUpMaxPriorityLimitInheritance = true;
433	if ( g_fCanRestorePriority
434	&& !setpriority(PRIO_PROCESS, 0, g_iMinPriority)
435	&& iStart != g_iMinPriority)
436	{
437	if (rtSchedRunThread(rtSchedNativeSubProberThread, (void *)(intptr_t)iStart) == 0)
438	g_fScrewedUpMaxPriorityLimitInheritance = false;
439	}
440
441	/* done */
442	rtSchedNativeRestore(&SavedPriority);
443	return (void *)VINF_SUCCESS;
444	}
445
446
447	/**
448	* Calculate the scheduling properties for all the threads in the default
449	* process priority, assuming the current thread have the type enmType.
450	*
451	* @returns iprt status code.
452	* @param enmType The thread type to be assumed for the current thread.
453	*/
454	DECLHIDDEN(int) rtSchedNativeCalcDefaultPriority(RTTHREADTYPE enmType)
455	{
456	Assert(enmType > RTTHREADTYPE_INVALID && enmType < RTTHREADTYPE_END);
457
458	/*
459	* First figure out what's we're allowed to do in this process.
460	*/
461	if (!g_fInitialized)
462	{
463	int iPriority = getpriority(PRIO_PROCESS, 0);
464	#ifdef RLIMIT_RTPRIO
465	/** @todo */
466	#endif
467	int rc = rtSchedRunThread(rtSchedNativeProberThread, NULL);
468	if (RT_FAILURE(rc))
469	return rc;
470	Assert(getpriority(PRIO_PROCESS, 0) == iPriority); NOREF(iPriority);
471	g_fInitialized = true;
472	}
473
474	/*
475	* Select the right priority type table and update the default
476	* process priority structure.
477	*/
478	if (g_fCanRaisePriority && g_fCanRestorePriority && !g_fScrewedUpMaxPriorityLimitInheritance)
479	g_aDefaultPriority.paTypes = &g_aTypesLinuxFree[0];
480	else if (!g_fCanRaisePriority && g_fCanRestorePriority && !g_fScrewedUpMaxPriorityLimitInheritance)
481	g_aDefaultPriority.paTypes = &g_aTypesLinuxRestricted[0];
482	else
483	g_aDefaultPriority.paTypes = &g_aTypesLinuxFlat[0];
484	Assert(enmType == g_aDefaultPriority.paTypes[enmType].enmType);
485
486	int iPriority = getpriority(PRIO_PROCESS, 0 /* current process */);
487	g_aDefaultPriority.iNice = iPriority - g_aDefaultPriority.paTypes[enmType].iPriority;
488	g_aDefaultPriority.iDelta = g_aDefaultPriority.iNice;
489
490	rtSchedDumpPriority();
491	return VINF_SUCCESS;
492	}
493
494
495	/**
496	* The process priority validator thread.
497	* (We don't want to mess with the priority of the calling thread.)
498	*/
499	static void rtSchedNativeValidatorThread(void pvUser)
500	{
501	const PROCPRIORITY pCfg = (const PROCPRIORITY )pvUser;
502	SAVEDPRIORITY SavedPriority;
503	rtSchedNativeSave(&SavedPriority);
504
505	/*
506	* Try out the priorities from the top and down.
507	*/
508	int rc = VINF_SUCCESS;
509	int i = RTTHREADTYPE_END;
510	while (--i > RTTHREADTYPE_INVALID)
511	{
512	int iPriority = pCfg->paTypes[i].iPriority + pCfg->iDelta;
513	if (setpriority(PRIO_PROCESS, 0, iPriority))
514	{
515	rc = RTErrConvertFromErrno(errno);
516	break;
517	}
518	}
519
520	/* done */
521	rtSchedNativeRestore(&SavedPriority);
522	return (void *)(intptr_t)rc;
523	}
524
525
526	/**
527	* Validates and sets the process priority.
528	*
529	* This will check that all rtThreadNativeSetPriority() will success for all the
530	* thread types when applied to the current thread.
531	*
532	* @returns iprt status code.
533	* @param enmPriority The priority to validate and set.
534	*/
535	DECLHIDDEN(int) rtProcNativeSetPriority(RTPROCPRIORITY enmPriority)
536	{
537	Assert(enmPriority > RTPROCPRIORITY_INVALID && enmPriority < RTPROCPRIORITY_LAST);
538
539	int rc = VINF_SUCCESS;
540	if (enmPriority == RTPROCPRIORITY_DEFAULT)
541	g_pProcessPriority = &g_aDefaultPriority;
542	else
543	{
544	/*
545	* Find a configuration which matches and can be applied.
546	*/
547	rc = VERR_FILE_NOT_FOUND;
548	for (unsigned i = 0; i < RT_ELEMENTS(g_aUnixConfigs); i++)
549	{
550	if (g_aUnixConfigs[i].enmPriority == enmPriority)
551	{
552	int iPriority = getpriority(PRIO_PROCESS, 0);
553	int rc3 = rtSchedRunThread(rtSchedNativeValidatorThread, (void *)&g_aUnixConfigs[i]);
554	Assert(getpriority(PRIO_PROCESS, 0) == iPriority); NOREF(iPriority);
555	if (RT_SUCCESS(rc3))
556	{
557	g_pProcessPriority = &g_aUnixConfigs[i];
558	rc = VINF_SUCCESS;
559	break;
560	}
561	if (rc == VERR_FILE_NOT_FOUND)
562	rc = rc3;
563	}
564	}
565	}
566
567	#ifdef THREAD_LOGGING
568	LogFlow(("rtProcNativeSetPriority: returns %Rrc enmPriority=%d\n", rc, enmPriority));
569	rtSchedDumpPriority();
570	#endif
571	return rc;
572	}
573
574
575	/**
576	* Sets the priority of the thread according to the thread type
577	* and current process priority.
578	*
579	* The RTTHREADINT::enmType member has not yet been updated and will be updated by
580	* the caller on a successful return.
581	*
582	* @returns iprt status code.
583	* @param pThread The thread in question.
584	* @param enmType The thread type.
585	*/
586	DECLHIDDEN(int) rtThreadNativeSetPriority(PRTTHREADINT pThread, RTTHREADTYPE enmType)
587	{
588	/* sanity */
589	Assert(enmType > RTTHREADTYPE_INVALID && enmType < RTTHREADTYPE_END);
590	Assert(enmType == g_pProcessPriority->paTypes[enmType].enmType);
591	Assert((pthread_t)pThread->Core.Key == pthread_self()); RT_NOREF_PV(pThread);
592
593	/*
594	* Calculate the thread priority and apply it.
595	*/
596	int rc = VINF_SUCCESS;
597	int iPriority = g_pProcessPriority->paTypes[enmType].iPriority + g_pProcessPriority->iDelta;
598	if (!setpriority(PRIO_PROCESS, 0, iPriority))
599	{
600	AssertMsg(iPriority == getpriority(PRIO_PROCESS, 0), ("iPriority=%d getpriority()=%d\n", iPriority, getpriority(PRIO_PROCESS, 0)));
601	#ifdef THREAD_LOGGING
602	Log(("rtThreadNativeSetPriority: Thread=%p enmType=%d iPriority=%d pid=%d\n", pThread->Core.Key, enmType, iPriority, getpid()));
603	#endif
604	}
605	else
606	{
607	rc = RTErrConvertFromErrno(errno);
608	AssertMsgFailed(("setpriority(,, %d) -> errno=%d rc=%Rrc\n", iPriority, errno, rc));
609	rc = VINF_SUCCESS; //non-fatal for now.
610	}
611
612	return rc;
613	}
614

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source: vbox/trunk/src/VBox/Runtime/r3/linux/sched-linux.cpp@ 76452

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