freebsd-dev/sys/kern/kern_resource.c
Konstantin Belousov 3364c323e6 Implement global and per-uid accounting of the anonymous memory. Add
rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved
for the uid.

The accounting information (charge) is associated with either map entry,
or vm object backing the entry, assuming the object is the first one
in the shadow chain and entry does not require COW. Charge is moved
from entry to object on allocation of the object, e.g. during the mmap,
assuming the object is allocated, or on the first page fault on the
entry. It moves back to the entry on forks due to COW setup.

The per-entry granularity of accounting makes the charge process fair
for processes that change uid during lifetime, and decrements charge
for proper uid when region is unmapped.

The interface of vm_pager_allocate(9) is extended by adding struct ucred *,
that is used to charge appropriate uid when allocation if performed by
kernel, e.g. md(4).

Several syscalls, among them is fork(2), may now return ENOMEM when
global or per-uid limits are enforced.

In collaboration with:	pho
Reviewed by:	alc
Approved by:	re (kensmith)
2009-06-23 20:45:22 +00:00

1364 lines
31 KiB
C

/*-
* 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.
* 4. 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_compat.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/file.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/refcount.h>
#include <sys/resourcevar.h>
#include <sys/rwlock.h>
#include <sys/sched.h>
#include <sys/sx.h>
#include <sys/syscallsubr.h>
#include <sys/sysent.h>
#include <sys/time.h>
#include <sys/umtx.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
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);
/*
* Resource controls and accounting.
*/
#ifndef _SYS_SYSPROTO_H_
struct getpriority_args {
int which;
int who;
};
#endif
int
getpriority(td, uap)
struct thread *td;
register 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_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) {
/* Do not bother to check PRS_NEW processes */
if (p->p_state == PRS_NEW)
continue;
PROC_LOCK(p);
if (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
setpriority(td, uap)
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_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_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);
}
/*
* Set realtime priority for LWP.
*/
#ifndef _SYS_SYSPROTO_H_
struct rtprio_thread_args {
int function;
lwpid_t lwpid;
struct rtprio *rtp;
};
#endif
int
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;
/*
* Though lwpid is unique, only current process is supported
* since there is no efficient way to look up a LWP yet.
*/
p = td->td_proc;
PROC_LOCK(p);
switch (uap->function) {
case RTP_LOOKUP:
if ((error = p_cansee(td, p)))
break;
if (uap->lwpid == 0 || uap->lwpid == td->td_tid)
td1 = td;
else
td1 = thread_find(p, uap->lwpid);
if (td1 != NULL)
pri_to_rtp(td1, &rtp);
else
error = ESRCH;
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 idle priority, 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
*/
#if 0
if (RTP_PRIO_IS_REALTIME(rtp.type)) {
#else
if (rtp.type != RTP_PRIO_NORMAL) {
#endif
error = priv_check(td, PRIV_SCHED_RTPRIO);
if (error)
break;
}
if (uap->lwpid == 0 || uap->lwpid == td->td_tid)
td1 = td;
else
td1 = thread_find(p, uap->lwpid);
if (td1 != NULL)
error = rtp_to_pri(&rtp, td1);
else
error = ESRCH;
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
rtprio(td, uap)
struct thread *td; /* curthread */
register 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. */
/*
* Realtime priority has to be restricted for reasons which should be
* obvious. However, for idle priority, 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
*/
#if 0
if (RTP_PRIO_IS_REALTIME(rtp.type)) {
#else
if (rtp.type != RTP_PRIO_NORMAL) {
#endif
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;
u_char oldpri;
if (rtp->prio > RTP_PRIO_MAX)
return (EINVAL);
thread_lock(td);
switch (RTP_PRIO_BASE(rtp->type)) {
case RTP_PRIO_REALTIME:
newpri = PRI_MIN_REALTIME + rtp->prio;
break;
case RTP_PRIO_NORMAL:
newpri = PRI_MIN_TIMESHARE + rtp->prio;
break;
case RTP_PRIO_IDLE:
newpri = PRI_MIN_IDLE + rtp->prio;
break;
default:
thread_unlock(td);
return (EINVAL);
}
sched_class(td, rtp->type); /* XXX fix */
oldpri = td->td_user_pri;
sched_user_prio(td, newpri);
if (curthread == td)
sched_prio(curthread, td->td_user_pri); /* XXX dubious */
if (TD_ON_UPILOCK(td) && oldpri != newpri) {
thread_unlock(td);
umtx_pi_adjust(td, oldpri);
} 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(td, uap)
struct thread *td;
register 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(td, uap)
struct thread *td;
register struct ogetrlimit_args *uap;
{
struct orlimit olim;
struct rlimit rl;
struct proc *p;
int error;
if (uap->which >= RLIM_NLIMITS)
return (EINVAL);
p = td->td_proc;
PROC_LOCK(p);
lim_rlimit(p, uap->which, &rl);
PROC_UNLOCK(p);
/*
* 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
setrlimit(td, uap)
struct thread *td;
register 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_SLOCK(p);
FOREACH_THREAD_IN_PROC(p, td) {
thread_lock(td);
ruxagg(&p->p_rux, td);
thread_unlock(td);
}
PROC_SUNLOCK(p);
if (p->p_rux.rux_runtime > p->p_cpulimit * cpu_tickrate()) {
lim_rlimit(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;
psignal(p, SIGXCPU);
}
}
if ((p->p_flag & P_WEXIT) == 0)
callout_reset(&p->p_limco, hz, lim_cb, p);
}
int
kern_setrlimit(td, which, limp)
struct thread *td;
u_int which;
struct rlimit *limp;
{
struct plimit *newlim, *oldlim;
struct proc *p;
register 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;
p = td->td_proc;
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(&p->p_limco, hz, lim_cb, p);
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 (td->td_proc->p_sysent->sv_fixlimit != NULL)
td->td_proc->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 (td->td_proc->p_sysent->sv_fixlimit != NULL)
td->td_proc->p_sysent->sv_fixlimit(limp, which);
*alimp = *limp;
p->p_limit = newlim;
PROC_UNLOCK(p);
lim_free(oldlim);
if (which == RLIMIT_STACK) {
/*
* 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
getrlimit(td, uap)
struct thread *td;
register struct __getrlimit_args *uap;
{
struct rlimit rlim;
struct proc *p;
int error;
if (uap->which >= RLIM_NLIMITS)
return (EINVAL);
p = td->td_proc;
PROC_LOCK(p);
lim_rlimit(p, uap->which, &rlim);
PROC_UNLOCK(p);
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(p, up, sp)
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 u;
PROC_LOCK_ASSERT(p, MA_OWNED);
PROC_SLOCK_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();
p->p_rux.rux_runtime += u - PCPU_GET(switchtime);
PCPU_SET(switchtime, u);
}
/* Make sure the per-thread stats are current. */
FOREACH_THREAD_IN_PROC(p, td) {
if (td->td_incruntime == 0)
continue;
thread_lock(td);
ruxagg(&p->p_rux, td);
thread_unlock(td);
}
calcru1(p, &p->p_rux, up, sp);
}
static void
calcru1(struct proc *p, struct rusage_ext *ruxp, struct timeval *up,
struct timeval *sp)
{
/* {user, system, interrupt, total} {ticks, usec}: */
u_int64_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;
}
if (tu >= ruxp->rux_tu) {
/*
* The normal case, time increased.
* Enforce monotonicity of bucketed numbers.
*/
uu = (tu * ut) / tt;
if (uu < ruxp->rux_uu)
uu = ruxp->rux_uu;
su = (tu * st) / tt;
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);
uu = (tu * ut) / tt;
su = (tu * st) / tt;
}
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
getrusage(td, uap)
register struct thread *td;
register 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(td, who, rup)
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;
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.
*/
void
ruxagg(struct rusage_ext *rux, struct thread *td)
{
THREAD_LOCK_ASSERT(td, MA_OWNED);
PROC_SLOCK_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;
td->td_incruntime = 0;
td->td_uticks = 0;
td->td_iticks = 0;
td->td_sticks = 0;
}
/*
* 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_SLOCK_ASSERT(p, MA_OWNED);
*ru = p->p_ru;
if (p->p_numthreads > 0) {
FOREACH_THREAD_IN_PROC(p, td) {
thread_lock(td);
ruxagg(&p->p_rux, td);
thread_unlock(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_SLOCK(p);
rufetch(p, ru);
calcru(p, up, sp);
PROC_SUNLOCK(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(limp)
struct plimit *limp;
{
refcount_acquire(&limp->pl_refcnt);
return (limp);
}
void
lim_fork(struct proc *p1, struct proc *p2)
{
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(&p2->p_limco, hz, lim_cb, p2);
}
void
lim_free(limp)
struct plimit *limp;
{
KASSERT(limp->pl_refcnt > 0, ("plimit refcnt underflow"));
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(dst, src)
struct plimit *dst, *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 proc *p, int which)
{
struct rlimit rl;
lim_rlimit(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 proc *p, int which)
{
struct rlimit rl;
lim_rlimit(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 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);
}
/*
* Find the uidinfo structure for a uid. This structure is used to
* track the total resource consumption (process count, socket buffer
* size, etc.) for the uid and impose limits.
*/
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.
*/
static struct uidinfo *
uilookup(uid)
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)
break;
return (uip);
}
/*
* Find or allocate a struct uidinfo for a particular uid.
* Increase refcount on uidinfo struct returned.
* uifree() should be called on a struct uidinfo when released.
*/
struct uidinfo *
uifind(uid)
uid_t uid;
{
struct uidinfo *old_uip, *uip;
rw_rlock(&uihashtbl_lock);
uip = uilookup(uid);
if (uip == NULL) {
rw_runlock(&uihashtbl_lock);
uip = malloc(sizeof(*uip), M_UIDINFO, M_WAITOK | M_ZERO);
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 ((old_uip = uilookup(uid)) != NULL) {
/* Someone else beat us to it. */
free(uip, M_UIDINFO);
uip = old_uip;
} else {
refcount_init(&uip->ui_ref, 0);
uip->ui_uid = uid;
mtx_init(&uip->ui_vmsize_mtx, "ui_vmsize", NULL,
MTX_DEF);
LIST_INSERT_HEAD(UIHASH(uid), uip, ui_hash);
}
}
uihold(uip);
rw_unlock(&uihashtbl_lock);
return (uip);
}
/*
* Place another refcount on a uidinfo struct.
*/
void
uihold(uip)
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(uip)
struct uidinfo *uip;
{
int old;
/* Prepare for optimal case. */
old = uip->ui_ref;
if (old > 1 && atomic_cmpset_int(&uip->ui_ref, old, old - 1))
return;
/* Prepare for suboptimal case. */
rw_wlock(&uihashtbl_lock);
if (refcount_release(&uip->ui_ref)) {
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);
mtx_destroy(&uip->ui_vmsize_mtx);
free(uip, M_UIDINFO);
return;
}
/*
* Someone added a reference between atomic_cmpset_int() and
* rw_wlock(&uihashtbl_lock).
*/
rw_wunlock(&uihashtbl_lock);
}
/*
* Change the count associated with number of processes
* a given user is using. When 'max' is 0, don't enforce a limit
*/
int
chgproccnt(uip, diff, max)
struct uidinfo *uip;
int diff;
rlim_t max;
{
/* Don't allow them to exceed max, but allow subtraction. */
if (diff > 0 && max != 0) {
if (atomic_fetchadd_long(&uip->ui_proccnt, (long)diff) + diff > max) {
atomic_subtract_long(&uip->ui_proccnt, (long)diff);
return (0);
}
} else {
atomic_add_long(&uip->ui_proccnt, (long)diff);
if (uip->ui_proccnt < 0)
printf("negative proccnt for uid = %d\n", uip->ui_uid);
}
return (1);
}
/*
* Change the total socket buffer size a user has used.
*/
int
chgsbsize(uip, hiwat, to, max)
struct uidinfo *uip;
u_int *hiwat;
u_int to;
rlim_t max;
{
int diff;
diff = to - *hiwat;
if (diff > 0) {
if (atomic_fetchadd_long(&uip->ui_sbsize, (long)diff) + diff > max) {
atomic_subtract_long(&uip->ui_sbsize, (long)diff);
return (0);
}
} else {
atomic_add_long(&uip->ui_sbsize, (long)diff);
if (uip->ui_sbsize < 0)
printf("negative sbsize for uid = %d\n", uip->ui_uid);
}
*hiwat = to;
return (1);
}
/*
* 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(uip, diff, max)
struct uidinfo *uip;
int diff;
rlim_t max;
{
/* Don't allow them to exceed max, but allow subtraction. */
if (diff > 0 && max != 0) {
if (atomic_fetchadd_long(&uip->ui_ptscnt, (long)diff) + diff > max) {
atomic_subtract_long(&uip->ui_ptscnt, (long)diff);
return (0);
}
} else {
atomic_add_long(&uip->ui_ptscnt, (long)diff);
if (uip->ui_ptscnt < 0)
printf("negative ptscnt for uid = %d\n", uip->ui_uid);
}
return (1);
}