/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1991, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. * All or some portions of this file are derived from material licensed * to the University of California by American Telephone and Telegraph * Co. or Unix System Laboratories, Inc. and are reproduced herein with * the permission of UNIX System Laboratories, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)kern_resource.c 8.5 (Berkeley) 1/21/94 */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static MALLOC_DEFINE(M_PLIMIT, "plimit", "plimit structures"); static MALLOC_DEFINE(M_UIDINFO, "uidinfo", "uidinfo structures"); #define UIHASH(uid) (&uihashtbl[(uid) & uihash]) static struct rwlock uihashtbl_lock; static LIST_HEAD(uihashhead, uidinfo) *uihashtbl; static u_long uihash; /* size of hash table - 1 */ static void calcru1(struct proc *p, struct rusage_ext *ruxp, struct timeval *up, struct timeval *sp); static int donice(struct thread *td, struct proc *chgp, int n); static struct uidinfo *uilookup(uid_t uid); static void ruxagg_locked(struct rusage_ext *rux, struct thread *td); /* * Resource controls and accounting. */ #ifndef _SYS_SYSPROTO_H_ struct getpriority_args { int which; int who; }; #endif int sys_getpriority(struct thread *td, struct getpriority_args *uap) { struct proc *p; struct pgrp *pg; int error, low; error = 0; low = PRIO_MAX + 1; switch (uap->which) { case PRIO_PROCESS: if (uap->who == 0) low = td->td_proc->p_nice; else { p = pfind(uap->who); if (p == NULL) break; if (p_cansee(td, p) == 0) low = p->p_nice; PROC_UNLOCK(p); } break; case PRIO_PGRP: sx_slock(&proctree_lock); if (uap->who == 0) { pg = td->td_proc->p_pgrp; PGRP_LOCK(pg); } else { pg = pgfind(uap->who); if (pg == NULL) { sx_sunlock(&proctree_lock); break; } } sx_sunlock(&proctree_lock); LIST_FOREACH(p, &pg->pg_members, p_pglist) { PROC_LOCK(p); if (p->p_state == PRS_NORMAL && p_cansee(td, p) == 0) { if (p->p_nice < low) low = p->p_nice; } PROC_UNLOCK(p); } PGRP_UNLOCK(pg); break; case PRIO_USER: if (uap->who == 0) uap->who = td->td_ucred->cr_uid; sx_slock(&allproc_lock); FOREACH_PROC_IN_SYSTEM(p) { PROC_LOCK(p); if (p->p_state == PRS_NORMAL && p_cansee(td, p) == 0 && p->p_ucred->cr_uid == uap->who) { if (p->p_nice < low) low = p->p_nice; } PROC_UNLOCK(p); } sx_sunlock(&allproc_lock); break; default: error = EINVAL; break; } if (low == PRIO_MAX + 1 && error == 0) error = ESRCH; td->td_retval[0] = low; return (error); } #ifndef _SYS_SYSPROTO_H_ struct setpriority_args { int which; int who; int prio; }; #endif int sys_setpriority(struct thread *td, struct setpriority_args *uap) { struct proc *curp, *p; struct pgrp *pg; int found = 0, error = 0; curp = td->td_proc; switch (uap->which) { case PRIO_PROCESS: if (uap->who == 0) { PROC_LOCK(curp); error = donice(td, curp, uap->prio); PROC_UNLOCK(curp); } else { p = pfind(uap->who); if (p == NULL) break; error = p_cansee(td, p); if (error == 0) error = donice(td, p, uap->prio); PROC_UNLOCK(p); } found++; break; case PRIO_PGRP: sx_slock(&proctree_lock); if (uap->who == 0) { pg = curp->p_pgrp; PGRP_LOCK(pg); } else { pg = pgfind(uap->who); if (pg == NULL) { sx_sunlock(&proctree_lock); break; } } sx_sunlock(&proctree_lock); LIST_FOREACH(p, &pg->pg_members, p_pglist) { PROC_LOCK(p); if (p->p_state == PRS_NORMAL && p_cansee(td, p) == 0) { error = donice(td, p, uap->prio); found++; } PROC_UNLOCK(p); } PGRP_UNLOCK(pg); break; case PRIO_USER: if (uap->who == 0) uap->who = td->td_ucred->cr_uid; sx_slock(&allproc_lock); FOREACH_PROC_IN_SYSTEM(p) { PROC_LOCK(p); if (p->p_state == PRS_NORMAL && p->p_ucred->cr_uid == uap->who && p_cansee(td, p) == 0) { error = donice(td, p, uap->prio); found++; } PROC_UNLOCK(p); } sx_sunlock(&allproc_lock); break; default: error = EINVAL; break; } if (found == 0 && error == 0) error = ESRCH; return (error); } /* * Set "nice" for a (whole) process. */ static int donice(struct thread *td, struct proc *p, int n) { int error; PROC_LOCK_ASSERT(p, MA_OWNED); if ((error = p_cansched(td, p))) return (error); if (n > PRIO_MAX) n = PRIO_MAX; if (n < PRIO_MIN) n = PRIO_MIN; if (n < p->p_nice && priv_check(td, PRIV_SCHED_SETPRIORITY) != 0) return (EACCES); sched_nice(p, n); return (0); } static int unprivileged_idprio; SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_idprio, CTLFLAG_RW, &unprivileged_idprio, 0, "Allow non-root users to set an idle priority"); /* * Set realtime priority for LWP. */ #ifndef _SYS_SYSPROTO_H_ struct rtprio_thread_args { int function; lwpid_t lwpid; struct rtprio *rtp; }; #endif int sys_rtprio_thread(struct thread *td, struct rtprio_thread_args *uap) { struct proc *p; struct rtprio rtp; struct thread *td1; int cierror, error; /* Perform copyin before acquiring locks if needed. */ if (uap->function == RTP_SET) cierror = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); else cierror = 0; if (uap->lwpid == 0 || uap->lwpid == td->td_tid) { p = td->td_proc; td1 = td; PROC_LOCK(p); } else { /* Only look up thread in current process */ td1 = tdfind(uap->lwpid, curproc->p_pid); if (td1 == NULL) return (ESRCH); p = td1->td_proc; } switch (uap->function) { case RTP_LOOKUP: if ((error = p_cansee(td, p))) break; pri_to_rtp(td1, &rtp); PROC_UNLOCK(p); return (copyout(&rtp, uap->rtp, sizeof(struct rtprio))); case RTP_SET: if ((error = p_cansched(td, p)) || (error = cierror)) break; /* Disallow setting rtprio in most cases if not superuser. */ /* * Realtime priority has to be restricted for reasons which * should be obvious. However, for idleprio processes, there is * a potential for system deadlock if an idleprio process gains * a lock on a resource that other processes need (and the * idleprio process can't run due to a CPU-bound normal * process). Fix me! XXX * * This problem is not only related to idleprio process. * A user level program can obtain a file lock and hold it * indefinitely. Additionally, without idleprio processes it is * still conceivable that a program with low priority will never * get to run. In short, allowing this feature might make it * easier to lock a resource indefinitely, but it is not the * only thing that makes it possible. */ if (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_REALTIME || (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_IDLE && unprivileged_idprio == 0)) { error = priv_check(td, PRIV_SCHED_RTPRIO); if (error) break; } error = rtp_to_pri(&rtp, td1); break; default: error = EINVAL; break; } PROC_UNLOCK(p); return (error); } /* * Set realtime priority. */ #ifndef _SYS_SYSPROTO_H_ struct rtprio_args { int function; pid_t pid; struct rtprio *rtp; }; #endif int sys_rtprio(struct thread *td, struct rtprio_args *uap) { struct proc *p; struct thread *tdp; struct rtprio rtp; int cierror, error; /* Perform copyin before acquiring locks if needed. */ if (uap->function == RTP_SET) cierror = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); else cierror = 0; if (uap->pid == 0) { p = td->td_proc; PROC_LOCK(p); } else { p = pfind(uap->pid); if (p == NULL) return (ESRCH); } switch (uap->function) { case RTP_LOOKUP: if ((error = p_cansee(td, p))) break; /* * Return OUR priority if no pid specified, * or if one is, report the highest priority * in the process. There isn't much more you can do as * there is only room to return a single priority. * Note: specifying our own pid is not the same * as leaving it zero. */ if (uap->pid == 0) { pri_to_rtp(td, &rtp); } else { struct rtprio rtp2; rtp.type = RTP_PRIO_IDLE; rtp.prio = RTP_PRIO_MAX; FOREACH_THREAD_IN_PROC(p, tdp) { pri_to_rtp(tdp, &rtp2); if (rtp2.type < rtp.type || (rtp2.type == rtp.type && rtp2.prio < rtp.prio)) { rtp.type = rtp2.type; rtp.prio = rtp2.prio; } } } PROC_UNLOCK(p); return (copyout(&rtp, uap->rtp, sizeof(struct rtprio))); case RTP_SET: if ((error = p_cansched(td, p)) || (error = cierror)) break; /* * Disallow setting rtprio in most cases if not superuser. * See the comment in sys_rtprio_thread about idprio * threads holding a lock. */ if (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_REALTIME || (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_IDLE && !unprivileged_idprio)) { error = priv_check(td, PRIV_SCHED_RTPRIO); if (error) break; } /* * If we are setting our own priority, set just our * thread but if we are doing another process, * do all the threads on that process. If we * specify our own pid we do the latter. */ if (uap->pid == 0) { error = rtp_to_pri(&rtp, td); } else { FOREACH_THREAD_IN_PROC(p, td) { if ((error = rtp_to_pri(&rtp, td)) != 0) break; } } break; default: error = EINVAL; break; } PROC_UNLOCK(p); return (error); } int rtp_to_pri(struct rtprio *rtp, struct thread *td) { u_char newpri, oldclass, oldpri; switch (RTP_PRIO_BASE(rtp->type)) { case RTP_PRIO_REALTIME: if (rtp->prio > RTP_PRIO_MAX) return (EINVAL); newpri = PRI_MIN_REALTIME + rtp->prio; break; case RTP_PRIO_NORMAL: if (rtp->prio > (PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE)) return (EINVAL); newpri = PRI_MIN_TIMESHARE + rtp->prio; break; case RTP_PRIO_IDLE: if (rtp->prio > RTP_PRIO_MAX) return (EINVAL); newpri = PRI_MIN_IDLE + rtp->prio; break; default: return (EINVAL); } thread_lock(td); oldclass = td->td_pri_class; sched_class(td, rtp->type); /* XXX fix */ oldpri = td->td_user_pri; sched_user_prio(td, newpri); if (td->td_user_pri != oldpri && (oldclass != RTP_PRIO_NORMAL || td->td_pri_class != RTP_PRIO_NORMAL)) sched_prio(td, td->td_user_pri); if (TD_ON_UPILOCK(td) && oldpri != newpri) { critical_enter(); thread_unlock(td); umtx_pi_adjust(td, oldpri); critical_exit(); } else thread_unlock(td); return (0); } void pri_to_rtp(struct thread *td, struct rtprio *rtp) { thread_lock(td); switch (PRI_BASE(td->td_pri_class)) { case PRI_REALTIME: rtp->prio = td->td_base_user_pri - PRI_MIN_REALTIME; break; case PRI_TIMESHARE: rtp->prio = td->td_base_user_pri - PRI_MIN_TIMESHARE; break; case PRI_IDLE: rtp->prio = td->td_base_user_pri - PRI_MIN_IDLE; break; default: break; } rtp->type = td->td_pri_class; thread_unlock(td); } #if defined(COMPAT_43) #ifndef _SYS_SYSPROTO_H_ struct osetrlimit_args { u_int which; struct orlimit *rlp; }; #endif int osetrlimit(struct thread *td, struct osetrlimit_args *uap) { struct orlimit olim; struct rlimit lim; int error; if ((error = copyin(uap->rlp, &olim, sizeof(struct orlimit)))) return (error); lim.rlim_cur = olim.rlim_cur; lim.rlim_max = olim.rlim_max; error = kern_setrlimit(td, uap->which, &lim); return (error); } #ifndef _SYS_SYSPROTO_H_ struct ogetrlimit_args { u_int which; struct orlimit *rlp; }; #endif int ogetrlimit(struct thread *td, struct ogetrlimit_args *uap) { struct orlimit olim; struct rlimit rl; int error; if (uap->which >= RLIM_NLIMITS) return (EINVAL); lim_rlimit(td, uap->which, &rl); /* * XXX would be more correct to convert only RLIM_INFINITY to the * old RLIM_INFINITY and fail with EOVERFLOW for other larger * values. Most 64->32 and 32->16 conversions, including not * unimportant ones of uids are even more broken than what we * do here (they blindly truncate). We don't do this correctly * here since we have little experience with EOVERFLOW yet. * Elsewhere, getuid() can't fail... */ olim.rlim_cur = rl.rlim_cur > 0x7fffffff ? 0x7fffffff : rl.rlim_cur; olim.rlim_max = rl.rlim_max > 0x7fffffff ? 0x7fffffff : rl.rlim_max; error = copyout(&olim, uap->rlp, sizeof(olim)); return (error); } #endif /* COMPAT_43 */ #ifndef _SYS_SYSPROTO_H_ struct __setrlimit_args { u_int which; struct rlimit *rlp; }; #endif int sys_setrlimit(struct thread *td, struct __setrlimit_args *uap) { struct rlimit alim; int error; if ((error = copyin(uap->rlp, &alim, sizeof(struct rlimit)))) return (error); error = kern_setrlimit(td, uap->which, &alim); return (error); } static void lim_cb(void *arg) { struct rlimit rlim; struct thread *td; struct proc *p; p = arg; PROC_LOCK_ASSERT(p, MA_OWNED); /* * Check if the process exceeds its cpu resource allocation. If * it reaches the max, arrange to kill the process in ast(). */ if (p->p_cpulimit == RLIM_INFINITY) return; PROC_STATLOCK(p); FOREACH_THREAD_IN_PROC(p, td) { ruxagg(p, td); } PROC_STATUNLOCK(p); if (p->p_rux.rux_runtime > p->p_cpulimit * cpu_tickrate()) { lim_rlimit_proc(p, RLIMIT_CPU, &rlim); if (p->p_rux.rux_runtime >= rlim.rlim_max * cpu_tickrate()) { killproc(p, "exceeded maximum CPU limit"); } else { if (p->p_cpulimit < rlim.rlim_max) p->p_cpulimit += 5; kern_psignal(p, SIGXCPU); } } if ((p->p_flag & P_WEXIT) == 0) callout_reset_sbt(&p->p_limco, SBT_1S, 0, lim_cb, p, C_PREL(1)); } int kern_setrlimit(struct thread *td, u_int which, struct rlimit *limp) { return (kern_proc_setrlimit(td, td->td_proc, which, limp)); } int kern_proc_setrlimit(struct thread *td, struct proc *p, u_int which, struct rlimit *limp) { struct plimit *newlim, *oldlim; struct rlimit *alimp; struct rlimit oldssiz; int error; if (which >= RLIM_NLIMITS) return (EINVAL); /* * Preserve historical bugs by treating negative limits as unsigned. */ if (limp->rlim_cur < 0) limp->rlim_cur = RLIM_INFINITY; if (limp->rlim_max < 0) limp->rlim_max = RLIM_INFINITY; oldssiz.rlim_cur = 0; newlim = lim_alloc(); PROC_LOCK(p); oldlim = p->p_limit; alimp = &oldlim->pl_rlimit[which]; if (limp->rlim_cur > alimp->rlim_max || limp->rlim_max > alimp->rlim_max) if ((error = priv_check(td, PRIV_PROC_SETRLIMIT))) { PROC_UNLOCK(p); lim_free(newlim); return (error); } if (limp->rlim_cur > limp->rlim_max) limp->rlim_cur = limp->rlim_max; lim_copy(newlim, oldlim); alimp = &newlim->pl_rlimit[which]; switch (which) { case RLIMIT_CPU: if (limp->rlim_cur != RLIM_INFINITY && p->p_cpulimit == RLIM_INFINITY) callout_reset_sbt(&p->p_limco, SBT_1S, 0, lim_cb, p, C_PREL(1)); p->p_cpulimit = limp->rlim_cur; break; case RLIMIT_DATA: if (limp->rlim_cur > maxdsiz) limp->rlim_cur = maxdsiz; if (limp->rlim_max > maxdsiz) limp->rlim_max = maxdsiz; break; case RLIMIT_STACK: if (limp->rlim_cur > maxssiz) limp->rlim_cur = maxssiz; if (limp->rlim_max > maxssiz) limp->rlim_max = maxssiz; oldssiz = *alimp; if (p->p_sysent->sv_fixlimit != NULL) p->p_sysent->sv_fixlimit(&oldssiz, RLIMIT_STACK); break; case RLIMIT_NOFILE: if (limp->rlim_cur > maxfilesperproc) limp->rlim_cur = maxfilesperproc; if (limp->rlim_max > maxfilesperproc) limp->rlim_max = maxfilesperproc; break; case RLIMIT_NPROC: if (limp->rlim_cur > maxprocperuid) limp->rlim_cur = maxprocperuid; if (limp->rlim_max > maxprocperuid) limp->rlim_max = maxprocperuid; if (limp->rlim_cur < 1) limp->rlim_cur = 1; if (limp->rlim_max < 1) limp->rlim_max = 1; break; } if (p->p_sysent->sv_fixlimit != NULL) p->p_sysent->sv_fixlimit(limp, which); *alimp = *limp; p->p_limit = newlim; PROC_UPDATE_COW(p); PROC_UNLOCK(p); lim_free(oldlim); if (which == RLIMIT_STACK && /* * Skip calls from exec_new_vmspace(), done when stack is * not mapped yet. */ (td != curthread || (p->p_flag & P_INEXEC) == 0)) { /* * Stack is allocated to the max at exec time with only * "rlim_cur" bytes accessible. If stack limit is going * up make more accessible, if going down make inaccessible. */ if (limp->rlim_cur != oldssiz.rlim_cur) { vm_offset_t addr; vm_size_t size; vm_prot_t prot; if (limp->rlim_cur > oldssiz.rlim_cur) { prot = p->p_sysent->sv_stackprot; size = limp->rlim_cur - oldssiz.rlim_cur; addr = p->p_sysent->sv_usrstack - limp->rlim_cur; } else { prot = VM_PROT_NONE; size = oldssiz.rlim_cur - limp->rlim_cur; addr = p->p_sysent->sv_usrstack - oldssiz.rlim_cur; } addr = trunc_page(addr); size = round_page(size); (void)vm_map_protect(&p->p_vmspace->vm_map, addr, addr + size, prot, FALSE); } } return (0); } #ifndef _SYS_SYSPROTO_H_ struct __getrlimit_args { u_int which; struct rlimit *rlp; }; #endif /* ARGSUSED */ int sys_getrlimit(struct thread *td, struct __getrlimit_args *uap) { struct rlimit rlim; int error; if (uap->which >= RLIM_NLIMITS) return (EINVAL); lim_rlimit(td, uap->which, &rlim); error = copyout(&rlim, uap->rlp, sizeof(struct rlimit)); return (error); } /* * Transform the running time and tick information for children of proc p * into user and system time usage. */ void calccru(struct proc *p, struct timeval *up, struct timeval *sp) { PROC_LOCK_ASSERT(p, MA_OWNED); calcru1(p, &p->p_crux, up, sp); } /* * Transform the running time and tick information in proc p into user * and system time usage. If appropriate, include the current time slice * on this CPU. */ void calcru(struct proc *p, struct timeval *up, struct timeval *sp) { struct thread *td; uint64_t runtime, u; PROC_LOCK_ASSERT(p, MA_OWNED); PROC_STATLOCK_ASSERT(p, MA_OWNED); /* * If we are getting stats for the current process, then add in the * stats that this thread has accumulated in its current time slice. * We reset the thread and CPU state as if we had performed a context * switch right here. */ td = curthread; if (td->td_proc == p) { u = cpu_ticks(); runtime = u - PCPU_GET(switchtime); td->td_runtime += runtime; td->td_incruntime += runtime; PCPU_SET(switchtime, u); } /* Make sure the per-thread stats are current. */ FOREACH_THREAD_IN_PROC(p, td) { if (td->td_incruntime == 0) continue; ruxagg(p, td); } calcru1(p, &p->p_rux, up, sp); } /* Collect resource usage for a single thread. */ void rufetchtd(struct thread *td, struct rusage *ru) { struct proc *p; uint64_t runtime, u; p = td->td_proc; PROC_STATLOCK_ASSERT(p, MA_OWNED); THREAD_LOCK_ASSERT(td, MA_OWNED); /* * If we are getting stats for the current thread, then add in the * stats that this thread has accumulated in its current time slice. * We reset the thread and CPU state as if we had performed a context * switch right here. */ if (td == curthread) { u = cpu_ticks(); runtime = u - PCPU_GET(switchtime); td->td_runtime += runtime; td->td_incruntime += runtime; PCPU_SET(switchtime, u); } ruxagg(p, td); *ru = td->td_ru; calcru1(p, &td->td_rux, &ru->ru_utime, &ru->ru_stime); } /* XXX: the MI version is too slow to use: */ #ifndef __HAVE_INLINE_FLSLL #define flsll(x) (fls((x) >> 32) != 0 ? fls((x) >> 32) + 32 : fls(x)) #endif static uint64_t mul64_by_fraction(uint64_t a, uint64_t b, uint64_t c) { uint64_t acc, bh, bl; int i, s, sa, sb; /* * Calculate (a * b) / c accurately enough without overflowing. c * must be nonzero, and its top bit must be 0. a or b must be * <= c, and the implementation is tuned for b <= c. * * The comments about times are for use in calcru1() with units of * microseconds for 'a' and stathz ticks at 128 Hz for b and c. * * Let n be the number of top zero bits in c. Each iteration * either returns, or reduces b by right shifting it by at least n. * The number of iterations is at most 1 + 64 / n, and the error is * at most the number of iterations. * * It is very unusual to need even 2 iterations. Previous * implementations overflowed essentially by returning early in the * first iteration, with n = 38 giving overflow at 105+ hours and * n = 32 giving overlow at at 388+ days despite a more careful * calculation. 388 days is a reasonable uptime, and the calculation * needs to work for the uptime times the number of CPUs since 'a' * is per-process. */ if (a >= (uint64_t)1 << 63) return (0); /* Unsupported arg -- can't happen. */ acc = 0; for (i = 0; i < 128; i++) { sa = flsll(a); sb = flsll(b); if (sa + sb <= 64) /* Up to 105 hours on first iteration. */ return (acc + (a * b) / c); if (a >= c) { /* * This reduction is based on a = q * c + r, with the * remainder r < c. 'a' may be large to start, and * moving bits from b into 'a' at the end of the loop * sets the top bit of 'a', so the reduction makes * significant progress. */ acc += (a / c) * b; a %= c; sa = flsll(a); if (sa + sb <= 64) /* Up to 388 days on first iteration. */ return (acc + (a * b) / c); } /* * This step writes a * b as a * ((bh << s) + bl) = * a * (bh << s) + a * bl = (a << s) * bh + a * bl. The 2 * additive terms are handled separately. Splitting in * this way is linear except for rounding errors. * * s = 64 - sa is the maximum such that a << s fits in 64 * bits. Since a < c and c has at least 1 zero top bit, * sa < 64 and s > 0. Thus this step makes progress by * reducing b (it increases 'a', but taking remainders on * the next iteration completes the reduction). * * Finally, the choice for s is just what is needed to keep * a * bl from overflowing, so we don't need complications * like a recursive call mul64_by_fraction(a, bl, c) to * handle the second additive term. */ s = 64 - sa; bh = b >> s; bl = b - (bh << s); acc += (a * bl) / c; a <<= s; b = bh; } return (0); /* Algorithm failure -- can't happen. */ } static void calcru1(struct proc *p, struct rusage_ext *ruxp, struct timeval *up, struct timeval *sp) { /* {user, system, interrupt, total} {ticks, usec}: */ uint64_t ut, uu, st, su, it, tt, tu; ut = ruxp->rux_uticks; st = ruxp->rux_sticks; it = ruxp->rux_iticks; tt = ut + st + it; if (tt == 0) { /* Avoid divide by zero */ st = 1; tt = 1; } tu = cputick2usec(ruxp->rux_runtime); if ((int64_t)tu < 0) { /* XXX: this should be an assert /phk */ printf("calcru: negative runtime of %jd usec for pid %d (%s)\n", (intmax_t)tu, p->p_pid, p->p_comm); tu = ruxp->rux_tu; } /* Subdivide tu. Avoid overflow in the multiplications. */ if (__predict_true(tu <= ((uint64_t)1 << 38) && tt <= (1 << 26))) { /* Up to 76 hours when stathz is 128. */ uu = (tu * ut) / tt; su = (tu * st) / tt; } else { uu = mul64_by_fraction(tu, ut, tt); su = mul64_by_fraction(tu, st, tt); } if (tu >= ruxp->rux_tu) { /* * The normal case, time increased. * Enforce monotonicity of bucketed numbers. */ if (uu < ruxp->rux_uu) uu = ruxp->rux_uu; if (su < ruxp->rux_su) su = ruxp->rux_su; } else if (tu + 3 > ruxp->rux_tu || 101 * tu > 100 * ruxp->rux_tu) { /* * When we calibrate the cputicker, it is not uncommon to * see the presumably fixed frequency increase slightly over * time as a result of thermal stabilization and NTP * discipline (of the reference clock). We therefore ignore * a bit of backwards slop because we expect to catch up * shortly. We use a 3 microsecond limit to catch low * counts and a 1% limit for high counts. */ uu = ruxp->rux_uu; su = ruxp->rux_su; tu = ruxp->rux_tu; } else { /* tu < ruxp->rux_tu */ /* * What happened here was likely that a laptop, which ran at * a reduced clock frequency at boot, kicked into high gear. * The wisdom of spamming this message in that case is * dubious, but it might also be indicative of something * serious, so lets keep it and hope laptops can be made * more truthful about their CPU speed via ACPI. */ printf("calcru: runtime went backwards from %ju usec " "to %ju usec for pid %d (%s)\n", (uintmax_t)ruxp->rux_tu, (uintmax_t)tu, p->p_pid, p->p_comm); } ruxp->rux_uu = uu; ruxp->rux_su = su; ruxp->rux_tu = tu; up->tv_sec = uu / 1000000; up->tv_usec = uu % 1000000; sp->tv_sec = su / 1000000; sp->tv_usec = su % 1000000; } #ifndef _SYS_SYSPROTO_H_ struct getrusage_args { int who; struct rusage *rusage; }; #endif int sys_getrusage(struct thread *td, struct getrusage_args *uap) { struct rusage ru; int error; error = kern_getrusage(td, uap->who, &ru); if (error == 0) error = copyout(&ru, uap->rusage, sizeof(struct rusage)); return (error); } int kern_getrusage(struct thread *td, int who, struct rusage *rup) { struct proc *p; int error; error = 0; p = td->td_proc; PROC_LOCK(p); switch (who) { case RUSAGE_SELF: rufetchcalc(p, rup, &rup->ru_utime, &rup->ru_stime); break; case RUSAGE_CHILDREN: *rup = p->p_stats->p_cru; calccru(p, &rup->ru_utime, &rup->ru_stime); break; case RUSAGE_THREAD: PROC_STATLOCK(p); thread_lock(td); rufetchtd(td, rup); thread_unlock(td); PROC_STATUNLOCK(p); break; default: error = EINVAL; } PROC_UNLOCK(p); return (error); } void rucollect(struct rusage *ru, struct rusage *ru2) { long *ip, *ip2; int i; if (ru->ru_maxrss < ru2->ru_maxrss) ru->ru_maxrss = ru2->ru_maxrss; ip = &ru->ru_first; ip2 = &ru2->ru_first; for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--) *ip++ += *ip2++; } void ruadd(struct rusage *ru, struct rusage_ext *rux, struct rusage *ru2, struct rusage_ext *rux2) { rux->rux_runtime += rux2->rux_runtime; rux->rux_uticks += rux2->rux_uticks; rux->rux_sticks += rux2->rux_sticks; rux->rux_iticks += rux2->rux_iticks; rux->rux_uu += rux2->rux_uu; rux->rux_su += rux2->rux_su; rux->rux_tu += rux2->rux_tu; rucollect(ru, ru2); } /* * Aggregate tick counts into the proc's rusage_ext. */ static void ruxagg_locked(struct rusage_ext *rux, struct thread *td) { THREAD_LOCK_ASSERT(td, MA_OWNED); PROC_STATLOCK_ASSERT(td->td_proc, MA_OWNED); rux->rux_runtime += td->td_incruntime; rux->rux_uticks += td->td_uticks; rux->rux_sticks += td->td_sticks; rux->rux_iticks += td->td_iticks; } void ruxagg(struct proc *p, struct thread *td) { thread_lock(td); ruxagg_locked(&p->p_rux, td); ruxagg_locked(&td->td_rux, td); td->td_incruntime = 0; td->td_uticks = 0; td->td_iticks = 0; td->td_sticks = 0; thread_unlock(td); } /* * Update the rusage_ext structure and fetch a valid aggregate rusage * for proc p if storage for one is supplied. */ void rufetch(struct proc *p, struct rusage *ru) { struct thread *td; PROC_STATLOCK_ASSERT(p, MA_OWNED); *ru = p->p_ru; if (p->p_numthreads > 0) { FOREACH_THREAD_IN_PROC(p, td) { ruxagg(p, td); rucollect(ru, &td->td_ru); } } } /* * Atomically perform a rufetch and a calcru together. * Consumers, can safely assume the calcru is executed only once * rufetch is completed. */ void rufetchcalc(struct proc *p, struct rusage *ru, struct timeval *up, struct timeval *sp) { PROC_STATLOCK(p); rufetch(p, ru); calcru(p, up, sp); PROC_STATUNLOCK(p); } /* * Allocate a new resource limits structure and initialize its * reference count and mutex pointer. */ struct plimit * lim_alloc() { struct plimit *limp; limp = malloc(sizeof(struct plimit), M_PLIMIT, M_WAITOK); refcount_init(&limp->pl_refcnt, 1); return (limp); } struct plimit * lim_hold(struct plimit *limp) { refcount_acquire(&limp->pl_refcnt); return (limp); } void lim_fork(struct proc *p1, struct proc *p2) { PROC_LOCK_ASSERT(p1, MA_OWNED); PROC_LOCK_ASSERT(p2, MA_OWNED); p2->p_limit = lim_hold(p1->p_limit); callout_init_mtx(&p2->p_limco, &p2->p_mtx, 0); if (p1->p_cpulimit != RLIM_INFINITY) callout_reset_sbt(&p2->p_limco, SBT_1S, 0, lim_cb, p2, C_PREL(1)); } void lim_free(struct plimit *limp) { if (refcount_release(&limp->pl_refcnt)) free((void *)limp, M_PLIMIT); } /* * Make a copy of the plimit structure. * We share these structures copy-on-write after fork. */ void lim_copy(struct plimit *dst, struct plimit *src) { KASSERT(dst->pl_refcnt <= 1, ("lim_copy to shared limit")); bcopy(src->pl_rlimit, dst->pl_rlimit, sizeof(src->pl_rlimit)); } /* * Return the hard limit for a particular system resource. The * which parameter specifies the index into the rlimit array. */ rlim_t lim_max(struct thread *td, int which) { struct rlimit rl; lim_rlimit(td, which, &rl); return (rl.rlim_max); } rlim_t lim_max_proc(struct proc *p, int which) { struct rlimit rl; lim_rlimit_proc(p, which, &rl); return (rl.rlim_max); } /* * Return the current (soft) limit for a particular system resource. * The which parameter which specifies the index into the rlimit array */ rlim_t (lim_cur)(struct thread *td, int which) { struct rlimit rl; lim_rlimit(td, which, &rl); return (rl.rlim_cur); } rlim_t lim_cur_proc(struct proc *p, int which) { struct rlimit rl; lim_rlimit_proc(p, which, &rl); return (rl.rlim_cur); } /* * Return a copy of the entire rlimit structure for the system limit * specified by 'which' in the rlimit structure pointed to by 'rlp'. */ void lim_rlimit(struct thread *td, int which, struct rlimit *rlp) { struct proc *p = td->td_proc; MPASS(td == curthread); KASSERT(which >= 0 && which < RLIM_NLIMITS, ("request for invalid resource limit")); *rlp = td->td_limit->pl_rlimit[which]; if (p->p_sysent->sv_fixlimit != NULL) p->p_sysent->sv_fixlimit(rlp, which); } void lim_rlimit_proc(struct proc *p, int which, struct rlimit *rlp) { PROC_LOCK_ASSERT(p, MA_OWNED); KASSERT(which >= 0 && which < RLIM_NLIMITS, ("request for invalid resource limit")); *rlp = p->p_limit->pl_rlimit[which]; if (p->p_sysent->sv_fixlimit != NULL) p->p_sysent->sv_fixlimit(rlp, which); } void uihashinit() { uihashtbl = hashinit(maxproc / 16, M_UIDINFO, &uihash); rw_init(&uihashtbl_lock, "uidinfo hash"); } /* * Look up a uidinfo struct for the parameter uid. * uihashtbl_lock must be locked. * Increase refcount on uidinfo struct returned. */ static struct uidinfo * uilookup(uid_t uid) { struct uihashhead *uipp; struct uidinfo *uip; rw_assert(&uihashtbl_lock, RA_LOCKED); uipp = UIHASH(uid); LIST_FOREACH(uip, uipp, ui_hash) if (uip->ui_uid == uid) { uihold(uip); break; } return (uip); } /* * Find or allocate a struct uidinfo for a particular uid. * Returns with uidinfo struct referenced. * uifree() should be called on a struct uidinfo when released. */ struct uidinfo * uifind(uid_t uid) { struct uidinfo *new_uip, *uip; struct ucred *cred; cred = curthread->td_ucred; if (cred->cr_uidinfo->ui_uid == uid) { uip = cred->cr_uidinfo; uihold(uip); return (uip); } else if (cred->cr_ruidinfo->ui_uid == uid) { uip = cred->cr_ruidinfo; uihold(uip); return (uip); } rw_rlock(&uihashtbl_lock); uip = uilookup(uid); rw_runlock(&uihashtbl_lock); if (uip != NULL) return (uip); new_uip = malloc(sizeof(*new_uip), M_UIDINFO, M_WAITOK | M_ZERO); racct_create(&new_uip->ui_racct); refcount_init(&new_uip->ui_ref, 1); new_uip->ui_uid = uid; rw_wlock(&uihashtbl_lock); /* * There's a chance someone created our uidinfo while we * were in malloc and not holding the lock, so we have to * make sure we don't insert a duplicate uidinfo. */ if ((uip = uilookup(uid)) == NULL) { LIST_INSERT_HEAD(UIHASH(uid), new_uip, ui_hash); rw_wunlock(&uihashtbl_lock); uip = new_uip; } else { rw_wunlock(&uihashtbl_lock); racct_destroy(&new_uip->ui_racct); free(new_uip, M_UIDINFO); } return (uip); } /* * Place another refcount on a uidinfo struct. */ void uihold(struct uidinfo *uip) { refcount_acquire(&uip->ui_ref); } /*- * Since uidinfo structs have a long lifetime, we use an * opportunistic refcounting scheme to avoid locking the lookup hash * for each release. * * If the refcount hits 0, we need to free the structure, * which means we need to lock the hash. * Optimal case: * After locking the struct and lowering the refcount, if we find * that we don't need to free, simply unlock and return. * Suboptimal case: * If refcount lowering results in need to free, bump the count * back up, lose the lock and acquire the locks in the proper * order to try again. */ void uifree(struct uidinfo *uip) { if (refcount_release_if_not_last(&uip->ui_ref)) return; rw_wlock(&uihashtbl_lock); if (refcount_release(&uip->ui_ref) == 0) { rw_wunlock(&uihashtbl_lock); return; } racct_destroy(&uip->ui_racct); LIST_REMOVE(uip, ui_hash); rw_wunlock(&uihashtbl_lock); if (uip->ui_sbsize != 0) printf("freeing uidinfo: uid = %d, sbsize = %ld\n", uip->ui_uid, uip->ui_sbsize); if (uip->ui_proccnt != 0) printf("freeing uidinfo: uid = %d, proccnt = %ld\n", uip->ui_uid, uip->ui_proccnt); if (uip->ui_vmsize != 0) printf("freeing uidinfo: uid = %d, swapuse = %lld\n", uip->ui_uid, (unsigned long long)uip->ui_vmsize); free(uip, M_UIDINFO); } #ifdef RACCT void ui_racct_foreach(void (*callback)(struct racct *racct, void *arg2, void *arg3), void (*pre)(void), void (*post)(void), void *arg2, void *arg3) { struct uidinfo *uip; struct uihashhead *uih; rw_rlock(&uihashtbl_lock); if (pre != NULL) (pre)(); for (uih = &uihashtbl[uihash]; uih >= uihashtbl; uih--) { LIST_FOREACH(uip, uih, ui_hash) { (callback)(uip->ui_racct, arg2, arg3); } } if (post != NULL) (post)(); rw_runlock(&uihashtbl_lock); } #endif static inline int chglimit(struct uidinfo *uip, long *limit, int diff, rlim_t max, const char *name) { long new; /* Don't allow them to exceed max, but allow subtraction. */ new = atomic_fetchadd_long(limit, (long)diff) + diff; if (diff > 0 && max != 0) { if (new < 0 || new > max) { atomic_subtract_long(limit, (long)diff); return (0); } } else if (new < 0) printf("negative %s for uid = %d\n", name, uip->ui_uid); return (1); } /* * Change the count associated with number of processes * a given user is using. When 'max' is 0, don't enforce a limit */ int chgproccnt(struct uidinfo *uip, int diff, rlim_t max) { return (chglimit(uip, &uip->ui_proccnt, diff, max, "proccnt")); } /* * Change the total socket buffer size a user has used. */ int chgsbsize(struct uidinfo *uip, u_int *hiwat, u_int to, rlim_t max) { int diff, rv; diff = to - *hiwat; if (diff > 0 && max == 0) { rv = 0; } else { rv = chglimit(uip, &uip->ui_sbsize, diff, max, "sbsize"); if (rv != 0) *hiwat = to; } return (rv); } /* * Change the count associated with number of pseudo-terminals * a given user is using. When 'max' is 0, don't enforce a limit */ int chgptscnt(struct uidinfo *uip, int diff, rlim_t max) { return (chglimit(uip, &uip->ui_ptscnt, diff, max, "ptscnt")); } int chgkqcnt(struct uidinfo *uip, int diff, rlim_t max) { return (chglimit(uip, &uip->ui_kqcnt, diff, max, "kqcnt")); } int chgumtxcnt(struct uidinfo *uip, int diff, rlim_t max) { return (chglimit(uip, &uip->ui_umtxcnt, diff, max, "umtxcnt")); }