/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License, Version 1.0 only * (the "License"). You may not use this file except in compliance * with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2004 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ /* All Rights Reserved */ #pragma ident "%Z%%M% %I% %E% SMI" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Structure used to pass arguments to the proccmp() function. * The arguments must be passed in a structure because proccmp() * is called indirectly through the dotoprocs() function which * will only pass through a single one word argument. */ struct pcmpargs { id_t *pcmp_cidp; int *pcmp_cntp; kthread_id_t *pcmp_retthreadp; }; /* * Structure used to pass arguments to the setparms() function * which is called indirectly through dotoprocs(). */ struct stprmargs { struct pcparms *stp_parmsp; /* pointer to parameters */ int stp_error; /* some errors returned here */ }; #if defined(_SYSCALL32_IMPL) && _LONG_LONG_ALIGNMENT_32 == 4 /* * A vaparm_t is an int followed by a long long -- this packs differently * between the 64-bit kernel ABI and the 32-bit user ABI. */ static int copyin_vaparms32(caddr_t arg, pc_vaparms_t *vap) { pc_vaparms32_t vaparms32; pc_vaparm32_t *src; pc_vaparm_t *dst; uint_t cnt; ASSERT(get_udatamodel() == DATAMODEL_ILP32); if (copyin(arg, &vaparms32, sizeof (vaparms32))) return (EFAULT); vap->pc_vaparmscnt = vaparms32.pc_vaparmscnt; if ((cnt = vaparms32.pc_vaparmscnt) > PC_VAPARMCNT) cnt = PC_VAPARMCNT; for (src = vaparms32.pc_parms, dst = vap->pc_parms; cnt--; src++, dst++) { dst->pc_key = src->pc_key; dst->pc_parm = src->pc_parm; } return (0); } #define COPYIN_VAPARMS(arg, vap, size) \ (get_udatamodel() == DATAMODEL_NATIVE ? \ copyin(arg, vap, size) : copyin_vaparms32(arg, vap)) #else #define COPYIN_VAPARMS(arg, vap, size) copyin(arg, vap, size) #endif static int donice(procset_t *, pcnice_t *); static int proccmp(proc_t *, struct pcmpargs *); static int setparms(proc_t *, struct stprmargs *); extern int threadcmp(struct pcmpargs *, kthread_id_t); /* * The priocntl system call. */ long priocntlsys(int pc_version, procset_t *psp, int cmd, caddr_t arg, caddr_t arg2) { pcinfo_t pcinfo; pcparms_t pcparms; pcnice_t pcnice; pcadmin_t pcadmin; pcpri_t pcpri; procset_t procset; struct stprmargs stprmargs; struct pcmpargs pcmpargs; pc_vaparms_t vaparms; char clname[PC_CLNMSZ]; int count; kthread_id_t retthreadp; proc_t *initpp; int clnullflag; int error = 0; int error1 = 0; int rv = 0; pid_t saved_pid; id_t classid; /* * First just check the version number. Right now there is only * one version we know about and support. If we get some other * version number from the application it may be that the * application was built with some future version and is trying * to run on an old release of the system (that's us). In any * case if we don't recognize the version number all we can do is * return error. */ if (pc_version != PC_VERSION) return (set_errno(EINVAL)); switch (cmd) { case PC_GETCID: /* * If the arg pointer is NULL, the user just wants to * know the number of classes. If non-NULL, the pointer * should point to a valid user pcinfo buffer. In the * dynamic world we need to return the number of loaded * classes, not the max number of available classes that * can be loaded. */ if (arg == NULL) { rv = loaded_classes; break; } else { if (copyin(arg, &pcinfo, sizeof (pcinfo))) return (set_errno(EFAULT)); } pcinfo.pc_clname[PC_CLNMSZ-1] = '\0'; /* * Get the class ID corresponding to user supplied name. */ error = getcid(pcinfo.pc_clname, &pcinfo.pc_cid); if (error) return (set_errno(error)); /* * Can't get info about the sys class. */ if (pcinfo.pc_cid == 0) return (set_errno(EINVAL)); /* * Get the class specific information. * we MUST make sure that the class has not already * been unloaded before we try the CL_GETCLINFO. * If it has then we need to load it. */ error = scheduler_load(pcinfo.pc_clname, &sclass[pcinfo.pc_cid]); if (error) return (set_errno(error)); error = CL_GETCLINFO(&sclass[pcinfo.pc_cid], pcinfo.pc_clinfo); if (error) return (set_errno(error)); if (copyout(&pcinfo, arg, sizeof (pcinfo))) return (set_errno(EFAULT)); rv = loaded_classes; break; case PC_GETCLINFO: /* * If the arg pointer is NULL, the user just wants to know * the number of classes. If non-NULL, the pointer should * point to a valid user pcinfo buffer. */ if (arg == NULL) { rv = loaded_classes; break; } else { if (copyin(arg, &pcinfo, sizeof (pcinfo))) return (set_errno(EFAULT)); } if (pcinfo.pc_cid >= loaded_classes || pcinfo.pc_cid < 1) return (set_errno(EINVAL)); (void) strncpy(pcinfo.pc_clname, sclass[pcinfo.pc_cid].cl_name, PC_CLNMSZ); /* * Get the class specific information. we MUST make sure * that the class has not already been unloaded before we * try the CL_GETCLINFO. If it has then we need to load * it. */ error = scheduler_load(pcinfo.pc_clname, &sclass[pcinfo.pc_cid]); if (error) return (set_errno(error)); error = CL_GETCLINFO(&sclass[pcinfo.pc_cid], pcinfo.pc_clinfo); if (error) return (set_errno(error)); if (copyout(&pcinfo, arg, sizeof (pcinfo))) return (set_errno(EFAULT)); rv = loaded_classes; break; case PC_SETPARMS: case PC_SETXPARMS: /* * First check the validity of the parameters we got from * the user. We don't do any permissions checking here * because it's done on a per thread basis by parmsset(). */ if (cmd == PC_SETPARMS) { if (copyin(arg, &pcparms, sizeof (pcparms))) return (set_errno(EFAULT)); error = parmsin(&pcparms, NULL); } else { if (copyin(arg, clname, PC_CLNMSZ) || COPYIN_VAPARMS(arg2, &vaparms, sizeof (vaparms))) return (set_errno(EFAULT)); clname[PC_CLNMSZ-1] = '\0'; if (getcid(clname, &pcparms.pc_cid)) return (set_errno(EINVAL)); error = parmsin(&pcparms, &vaparms); } if (error) return (set_errno(error)); /* * Get the procset from the user. */ if (copyin(psp, &procset, sizeof (procset))) return (set_errno(EFAULT)); /* * For performance we do a quick check here to catch * common cases where the current thread is the only one * in the set. In such cases we can call parmsset() * directly, avoiding the relatively lengthy path through * dotoprocs(). The underlying classes expect pidlock to * be held. */ if (cur_inset_only(&procset) == B_TRUE) { /* do a single LWP */ if ((procset.p_lidtype == P_LWPID) || (procset.p_ridtype == P_LWPID)) { mutex_enter(&pidlock); mutex_enter(&curproc->p_lock); error = parmsset(&pcparms, curthread); mutex_exit(&curproc->p_lock); mutex_exit(&pidlock); } else { /* do the entire process otherwise */ stprmargs.stp_parmsp = &pcparms; stprmargs.stp_error = 0; mutex_enter(&pidlock); error = setparms(curproc, &stprmargs); mutex_exit(&pidlock); if (error == 0 && stprmargs.stp_error != 0) error = stprmargs.stp_error; } if (error) return (set_errno(error)); } else { stprmargs.stp_parmsp = &pcparms; stprmargs.stp_error = 0; error1 = error = ESRCH; /* * The dotoprocs() call below will cause * setparms() to be called for each thread in the * specified procset. setparms() will in turn * call parmsset() (which does the real work). */ if ((procset.p_lidtype != P_LWPID) || (procset.p_ridtype != P_LWPID)) { error1 = dotoprocs(&procset, setparms, (char *)&stprmargs); } /* * take care of the case when any of the * operands happen to be LWP's */ if ((procset.p_lidtype == P_LWPID) || (procset.p_ridtype == P_LWPID)) { error = dotolwp(&procset, parmsset, (char *)&pcparms); /* * Dotolwp() returns with p_lock held. * This is required for the GETPARMS case * below. So, here we just release the * p_lock. */ if (MUTEX_HELD(&curproc->p_lock)) mutex_exit(&curproc->p_lock); } /* * If setparms() encounters a permissions error * for one or more of the threads it returns * EPERM in stp_error so dotoprocs() will * continue through the thread set. If * dotoprocs() returned an error above, it was * more serious than permissions and dotoprocs * quit when the error was encountered. We * return the more serious error if there was * one, otherwise we return EPERM if we got that * back. */ if (error1 != ESRCH) error = error1; if (error == 0 && stprmargs.stp_error != 0) error = stprmargs.stp_error; } break; case PC_GETPARMS: case PC_GETXPARMS: if (cmd == PC_GETPARMS) { if (copyin(arg, &pcparms, sizeof (pcparms))) return (set_errno(EFAULT)); } else { if (arg != NULL) { if (copyin(arg, clname, PC_CLNMSZ)) return (set_errno(EFAULT)); clname[PC_CLNMSZ-1] = '\0'; if (getcid(clname, &pcparms.pc_cid)) return (set_errno(EINVAL)); } else pcparms.pc_cid = PC_CLNULL; if (COPYIN_VAPARMS(arg2, &vaparms, sizeof (vaparms))) return (set_errno(EFAULT)); } if (pcparms.pc_cid >= loaded_classes || (pcparms.pc_cid < 1 && pcparms.pc_cid != PC_CLNULL)) return (set_errno(EINVAL)); if (copyin(psp, &procset, sizeof (procset))) return (set_errno(EFAULT)); /* * Check to see if the current thread is the only one * in the set. If not we must go through the whole set * to select a thread. */ if (cur_inset_only(&procset) == B_TRUE) { /* do a single LWP */ if ((procset.p_lidtype == P_LWPID) || (procset.p_ridtype == P_LWPID)) { if (pcparms.pc_cid != PC_CLNULL && pcparms.pc_cid != curthread->t_cid) { /* * Specified thread not in * specified class. */ return (set_errno(ESRCH)); } else { mutex_enter(&curproc->p_lock); retthreadp = curthread; } } else { count = 0; retthreadp = NULL; pcmpargs.pcmp_cidp = &pcparms.pc_cid; pcmpargs.pcmp_cntp = &count; pcmpargs.pcmp_retthreadp = &retthreadp; /* * Specified thread not in specified class. */ if (pcparms.pc_cid != PC_CLNULL && pcparms.pc_cid != curthread->t_cid) return (set_errno(ESRCH)); error = proccmp(curproc, &pcmpargs); if (error) { if (retthreadp != NULL) mutex_exit(&(curproc->p_lock)); return (set_errno(error)); } } } else { /* * get initpp early to avoid lock ordering problems * (we cannot get pidlock while holding any p_lock). */ mutex_enter(&pidlock); initpp = prfind(P_INITPID); mutex_exit(&pidlock); /* * Select the thread (from the set) whose * parameters we are going to return. First we * set up some locations for return values, then * we call proccmp() indirectly through * dotoprocs(). proccmp() will call a class * specific routine which actually does the * selection. To understand how this works take * a careful look at the code below, the * dotoprocs() function, the proccmp() function, * and the class specific cl_proccmp() functions. */ if (pcparms.pc_cid == PC_CLNULL) clnullflag = 1; else clnullflag = 0; count = 0; retthreadp = NULL; pcmpargs.pcmp_cidp = &pcparms.pc_cid; pcmpargs.pcmp_cntp = &count; pcmpargs.pcmp_retthreadp = &retthreadp; error1 = error = ESRCH; if ((procset.p_lidtype != P_LWPID) || (procset.p_ridtype != P_LWPID)) { error1 = dotoprocs(&procset, proccmp, (char *)&pcmpargs); } /* * take care of combination of LWP and process * set case in a procset */ if ((procset.p_lidtype == P_LWPID) || (procset.p_ridtype == P_LWPID)) { error = dotolwp(&procset, threadcmp, (char *)&pcmpargs); } /* * Both proccmp() and threadcmp() return with the * p_lock held for the ttoproc(retthreadp). This * is required to make sure that the process we * chose as the winner doesn't go away * i.e. retthreadp has to be a valid pointer. * * The case below can only happen if the thread * with the highest priority was not in your * process. In that case, dotolwp will return * holding p_lock for both your process as well * as the process in which retthreadp is a * thread. */ if ((retthreadp != NULL) && (ttoproc(retthreadp) != curproc) && MUTEX_HELD(&(curproc)->p_lock)) mutex_exit(&(curproc)->p_lock); ASSERT(retthreadp == NULL || MUTEX_HELD(&(ttoproc(retthreadp)->p_lock))); if (error1 != ESRCH) error = error1; if (error) { if (retthreadp != NULL) mutex_exit(&(ttoproc(retthreadp)->p_lock)); ASSERT(MUTEX_NOT_HELD(&(curproc)->p_lock)); return (set_errno(error)); } /* * dotoprocs() ignores the init process if it is * in the set, unless it was the only process found. * Since we are getting parameters here rather than * setting them, we want to make sure init is not * excluded if it is in the set. */ if (initpp != NULL && procinset(initpp, &procset) && (retthreadp != NULL) && ttoproc(retthreadp) != initpp) (void) proccmp(initpp, &pcmpargs); /* * If dotoprocs returned success it found at least * one thread in the set. If proccmp() failed to * select a thread it is because the user specified * a class and none of the threads in the set * belonged to that class, or because the process * specified was in the middle of exiting and had * cleared its thread list. */ if (retthreadp == NULL) { /* * Might be here and still holding p_lock * if we did a dotolwp on an lwp that * existed but was in the wrong class. */ if (MUTEX_HELD(&(curproc)->p_lock)) mutex_exit(&(curproc)->p_lock); return (set_errno(ESRCH)); } /* * User can only use PC_CLNULL with one thread in set. */ if (clnullflag && count > 1) { if (retthreadp != NULL) mutex_exit( &(ttoproc(retthreadp)->p_lock)); ASSERT(MUTEX_NOT_HELD(&(curproc)->p_lock)); return (set_errno(EINVAL)); } } ASSERT(retthreadp == NULL || MUTEX_HELD(&(ttoproc(retthreadp)->p_lock))); /* * It is possible to have retthreadp == NULL. Proccmp() * in the rare case (p_tlist == NULL) could return without * setting a value for retthreadp. */ if (retthreadp == NULL) { ASSERT(MUTEX_NOT_HELD(&(curproc)->p_lock)); return (set_errno(ESRCH)); } /* * We've selected a thread so now get the parameters. */ parmsget(retthreadp, &pcparms); /* * Prepare to return parameters to the user */ error = parmsout(&pcparms, (cmd == PC_GETPARMS ? NULL : &vaparms)); /* * Save pid of selected thread before dropping p_lock. */ saved_pid = ttoproc(retthreadp)->p_pid; mutex_exit(&(ttoproc(retthreadp)->p_lock)); ASSERT(MUTEX_NOT_HELD(&curproc->p_lock)); if (error) return (set_errno(error)); if (cmd == PC_GETPARMS) { if (copyout(&pcparms, arg, sizeof (pcparms))) return (set_errno(EFAULT)); } else if ((error = vaparmsout(arg, &pcparms, &vaparms)) != 0) return (set_errno(error)); /* * And finally, return the pid of the selected thread. */ rv = saved_pid; break; case PC_ADMIN: if (get_udatamodel() == DATAMODEL_NATIVE) { if (copyin(arg, &pcadmin, sizeof (pcadmin_t))) return (set_errno(EFAULT)); #ifdef _SYSCALL32_IMPL } else { /* pcadmin struct from ILP32 callers */ pcadmin32_t pcadmin32; if (copyin(arg, &pcadmin32, sizeof (pcadmin32_t))) return (set_errno(EFAULT)); pcadmin.pc_cid = pcadmin32.pc_cid; pcadmin.pc_cladmin = (caddr_t)(uintptr_t) pcadmin32.pc_cladmin; #endif /* _SYSCALL32_IMPL */ } if (pcadmin.pc_cid >= loaded_classes || pcadmin.pc_cid < 1) return (set_errno(EINVAL)); /* * Have the class do whatever the user is requesting. */ mutex_enter(&ualock); error = CL_ADMIN(&sclass[pcadmin.pc_cid], pcadmin.pc_cladmin, CRED()); mutex_exit(&ualock); break; case PC_GETPRIRANGE: if (copyin(arg, &pcpri, sizeof (pcpri_t))) return (set_errno(EFAULT)); if (pcpri.pc_cid >= loaded_classes || pcpri.pc_cid < 0) return (set_errno(EINVAL)); error = CL_GETCLPRI(&sclass[pcpri.pc_cid], &pcpri); if (!error) { if (copyout(&pcpri, arg, sizeof (pcpri))) return (set_errno(EFAULT)); } break; case PC_DONICE: /* * Get pcnice and procset structures from the user. */ if (copyin(arg, &pcnice, sizeof (pcnice)) || copyin(psp, &procset, sizeof (procset))) return (set_errno(EFAULT)); error = donice(&procset, &pcnice); if (!error && (pcnice.pc_op == PC_GETNICE)) { if (copyout(&pcnice, arg, sizeof (pcnice))) return (set_errno(EFAULT)); } break; case PC_SETDFLCL: if (secpolicy_dispadm(CRED()) != 0) return (set_errno(EPERM)); if (copyin(arg, (caddr_t)clname, PC_CLNMSZ) != 0) return (set_errno(EFAULT)); clname[PC_CLNMSZ-1] = '\0'; if (getcid(clname, &classid) != 0) return (set_errno(EINVAL)); if (classid == syscid) return (set_errno(EINVAL)); defaultcid = classid; ASSERT(defaultcid > 0 && defaultcid < loaded_classes); break; default: error = EINVAL; break; } return (error ? (set_errno(error)) : rv); } /* * The proccmp() function is part of the implementation of the * PC_GETPARMS command of the priocntl system call. This function works * with the system call code and with the class specific cl_globpri() * function to select one thread from a specified procset based on class * specific criteria. proccmp() is called indirectly from the priocntl * code through the dotoprocs function. Basic strategy is dotoprocs() * calls us once for each thread in the set. We in turn call the class * specific function to compare the current thread from dotoprocs to the * "best" (according to the class criteria) found so far. We keep the * "best" thread in *pcmp_retthreadp. */ static int proccmp(proc_t *pp, struct pcmpargs *argp) { kthread_id_t tx, ty; int last_pri = -1; int tx_pri; int found = 0; mutex_enter(&pp->p_lock); if (pp->p_tlist == NULL) { mutex_exit(&pp->p_lock); return (0); } (*argp->pcmp_cntp)++; /* Increment count of procs in the set */ if (*argp->pcmp_cidp == PC_CLNULL) { /* * If no cid is specified, then lets just pick the first one. * It doesn't matter because if the number of processes in the * set are more than 1, then we return EINVAL in priocntlsys. */ *argp->pcmp_cidp = pp->p_tlist->t_cid; } ty = tx = pp->p_tlist; do { if (tx->t_cid == *argp->pcmp_cidp) { /* * We found one which matches the required cid. */ found = 1; if ((tx_pri = CL_GLOBPRI(tx)) > last_pri) { last_pri = tx_pri; ty = tx; } } } while ((tx = tx->t_forw) != pp->p_tlist); if (found) { if (*argp->pcmp_retthreadp == NULL) { /* * First time through for this set. * keep the mutex held. He might be the one! */ *argp->pcmp_retthreadp = ty; } else { tx = *argp->pcmp_retthreadp; if (CL_GLOBPRI(ty) <= CL_GLOBPRI(tx)) { mutex_exit(&pp->p_lock); } else { mutex_exit(&(ttoproc(tx)->p_lock)); *argp->pcmp_retthreadp = ty; } } } else { /* * We actually didn't find anything of the same cid in * this process. */ mutex_exit(&pp->p_lock); } return (0); } int threadcmp(struct pcmpargs *argp, kthread_id_t tp) { kthread_id_t tx; proc_t *pp; ASSERT(MUTEX_HELD(&(ttoproc(tp))->p_lock)); (*argp->pcmp_cntp)++; /* Increment count of procs in the set */ if (*argp->pcmp_cidp == PC_CLNULL) { /* * If no cid is specified, then lets just pick the first one. * It doesn't matter because if the number of threads in the * set are more than 1, then we return EINVAL in priocntlsys. */ *argp->pcmp_cidp = tp->t_cid; } if (tp->t_cid == *argp->pcmp_cidp) { if (*argp->pcmp_retthreadp == NULL) { /* * First time through for this set. */ *argp->pcmp_retthreadp = tp; } else { tx = *argp->pcmp_retthreadp; if (CL_GLOBPRI(tp) > CL_GLOBPRI(tx)) { /* * Unlike proccmp(), we don't release the * p_lock of the ttoproc(tp) if tp's global * priority is less than tx's. We need to go * through the entire list before we can do * that. The p_lock is released by the caller * of dotolwp(). */ pp = ttoproc(tx); ASSERT(MUTEX_HELD(&pp->p_lock)); if (pp != curproc) { mutex_exit(&pp->p_lock); } *argp->pcmp_retthreadp = tp; } } } return (0); } /* * The setparms() function is called indirectly by priocntlsys() * through the dotoprocs() function. setparms() acts as an * intermediary between dotoprocs() and the parmsset() function, * calling parmsset() for each thread in the set and handling * the error returns on their way back up to dotoprocs(). */ static int setparms(proc_t *targpp, struct stprmargs *stprmp) { int error = 0; kthread_id_t t; int err; mutex_enter(&targpp->p_lock); if ((t = targpp->p_tlist) == NULL) { mutex_exit(&targpp->p_lock); return (0); } do { err = parmsset(stprmp->stp_parmsp, t); if (error == 0) error = err; } while ((t = t->t_forw) != targpp->p_tlist); mutex_exit(&targpp->p_lock); if (error) { if (error == EPERM) { stprmp->stp_error = EPERM; return (0); } else { return (error); } } else return (0); } static int setthreadnice(pcnice_t *pcnice, kthread_t *tp) { int error = 0; int nice; int inc; id_t rtcid; ASSERT(MUTEX_HELD(&pidlock)); ASSERT(MUTEX_HELD(&(ttoproc(tp)->p_lock))); /* * The XPG5 standard requires that any realtime process or thread * must be unaffected by a call to setpriority(). */ error = getcidbyname("RT", &rtcid); if ((error == 0) && (tp->t_cid == rtcid)) { if (pcnice->pc_op == PC_SETNICE) return (error); } if ((error = CL_DONICE(tp, CRED(), 0, &nice)) != 0) return (error); if (pcnice->pc_op == PC_GETNICE) { /* * If there is no change to priority, we should return the * highest priority (lowest numerical value) pertaining to * any of the specified threads. */ if (nice < pcnice->pc_val) pcnice->pc_val = nice; } else { ASSERT(pcnice->pc_op == PC_SETNICE); /* * Try to change the nice value of the thread. */ inc = pcnice->pc_val - nice; error = CL_DONICE(tp, CRED(), inc, &inc); } return (error); } static int setprocnice(proc_t *pp, pcnice_t *pcnice) { kthread_t *tp; int retval = 0; int error = 0; ASSERT(MUTEX_HELD(&pidlock)); mutex_enter(&pp->p_lock); if ((tp = pp->p_tlist) == NULL) { mutex_exit(&pp->p_lock); return (ESRCH); } /* * Check permissions before changing the nice value. */ if (pcnice->pc_op == PC_SETNICE) { if (!prochasprocperm(pp, curproc, CRED())) { mutex_exit(&pp->p_lock); return (EPERM); } } do { error = setthreadnice(pcnice, tp); if (error) retval = error; } while ((tp = tp->t_forw) != pp->p_tlist); mutex_exit(&pp->p_lock); return (retval); } /* * Update the nice value of the specified LWP or set of processes. */ static int donice(procset_t *procset, pcnice_t *pcnice) { int err_proc = 0; int err_thread = 0; int err = 0; /* * Sanity check. */ if (pcnice->pc_op != PC_GETNICE && pcnice->pc_op != PC_SETNICE) return (EINVAL); /* * If it is PC_GETNICE operation then set pc_val to the largest * possible nice value to help us find the lowest nice value * pertaining to any of the specified processes. */ if (pcnice->pc_op == PC_GETNICE) pcnice->pc_val = NZERO; if (procset->p_lidtype != P_LWPID || procset->p_ridtype != P_LWPID) err_proc = dotoprocs(procset, setprocnice, (char *)pcnice); if (procset->p_lidtype == P_LWPID || procset->p_ridtype == P_LWPID) { err_thread = dotolwp(procset, setthreadnice, (char *)pcnice); /* * dotolwp() can return with p_lock held. This is required * for the priocntl GETPARMS case. So, here we just release * the p_lock. */ if (MUTEX_HELD(&curproc->p_lock)) mutex_exit(&curproc->p_lock); /* * If we were called for a single LWP, then ignore ESRCH * returned by the previous dotoprocs() call. */ if (err_proc == ESRCH) err_proc = 0; } /* * dotoprocs() ignores the init process if it is in the set, unless * it was the only process found. We want to make sure init is not * excluded if we're going PC_GETNICE operation. */ if (pcnice->pc_op == PC_GETNICE) { proc_t *initpp; mutex_enter(&pidlock); initpp = prfind(P_INITPID); if (initpp != NULL && procinset(initpp, procset)) err = setprocnice(initpp, pcnice); mutex_exit(&pidlock); } /* * We're returning the latest error here that we've got back from * the setthreadnice() or setprocnice(). That is, err_thread and/or * err_proc can be replaced by err. */ if (!err) err = err_thread ? err_thread : err_proc; return (err); }