subr_syscall.c revision 126661
14Srgrimes/*- 21690Sdg * Copyright (C) 1994, David Greenman 31690Sdg * Copyright (c) 1990, 1993 41690Sdg * The Regents of the University of California. All rights reserved. 54Srgrimes * 64Srgrimes * This code is derived from software contributed to Berkeley by 74Srgrimes * the University of Utah, and William Jolitz. 84Srgrimes * 94Srgrimes * Redistribution and use in source and binary forms, with or without 104Srgrimes * modification, are permitted provided that the following conditions 114Srgrimes * are met: 124Srgrimes * 1. Redistributions of source code must retain the above copyright 134Srgrimes * notice, this list of conditions and the following disclaimer. 144Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 154Srgrimes * notice, this list of conditions and the following disclaimer in the 164Srgrimes * documentation and/or other materials provided with the distribution. 174Srgrimes * 3. All advertising materials mentioning features or use of this software 184Srgrimes * must display the following acknowledgement: 194Srgrimes * This product includes software developed by the University of 204Srgrimes * California, Berkeley and its contributors. 214Srgrimes * 4. Neither the name of the University nor the names of its contributors 224Srgrimes * may be used to endorse or promote products derived from this software 234Srgrimes * without specific prior written permission. 244Srgrimes * 254Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 264Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 274Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 284Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 294Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 304Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 314Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 324Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 334Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 344Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 354Srgrimes * SUCH DAMAGE. 364Srgrimes * 37608Srgrimes * from: @(#)trap.c 7.4 (Berkeley) 5/13/91 384Srgrimes */ 394Srgrimes 40116182Sobrien#include <sys/cdefs.h> 41116182Sobrien__FBSDID("$FreeBSD: head/sys/kern/subr_trap.c 126661 2004-03-05 17:35:28Z rwatson $"); 42116182Sobrien 43118240Speter#include "opt_ktrace.h" 44104338Srwatson#include "opt_mac.h" 4578983Sjhb#ifdef __i386__ 4671257Speter#include "opt_npx.h" 4778983Sjhb#endif 4813203Swollman 491549Srgrimes#include <sys/param.h> 5065557Sjasone#include <sys/bus.h> 511549Srgrimes#include <sys/kernel.h> 5278983Sjhb#include <sys/lock.h> 53104338Srwatson#include <sys/mac.h> 5467365Sjhb#include <sys/mutex.h> 5578983Sjhb#include <sys/proc.h> 5699072Sjulian#include <sys/ktr.h> 5731389Sbde#include <sys/resourcevar.h> 58104964Sjeff#include <sys/sched.h> 5931389Sbde#include <sys/signalvar.h> 6078983Sjhb#include <sys/systm.h> 6112662Sdg#include <sys/vmmeter.h> 62118240Speter#ifdef KTRACE 63118240Speter#include <sys/uio.h> 64118240Speter#include <sys/ktrace.h> 65118240Speter#endif 66118240Speter 671549Srgrimes#include <machine/cpu.h> 6831389Sbde#include <machine/pcb.h> 691549Srgrimes 7078983Sjhb/* 7178983Sjhb * Define the code needed before returning to user mode, for 7278983Sjhb * trap and syscall. 7382585Sdillon * 7482585Sdillon * MPSAFE 7578983Sjhb */ 7671527Sjhbvoid 7783366Sjulianuserret(td, frame, oticks) 7883366Sjulian struct thread *td; 791690Sdg struct trapframe *frame; 8081493Sjhb u_int oticks; 811690Sdg{ 8283366Sjulian struct proc *p = td->td_proc; 83757Sdg 8499072Sjulian CTR3(KTR_SYSC, "userret: thread %p (pid %d, %s)", td, p->p_pid, 8599072Sjulian p->p_comm); 86126661Srwatson#ifdef DIAGNOSTIC 87110190Sjulian /* Check that we called signotify() enough. */ 8878636Sjhb PROC_LOCK(p); 8993793Sbde mtx_lock_spin(&sched_lock); 90112888Sjeff if (SIGPENDING(td) && ((td->td_flags & TDF_NEEDSIGCHK) == 0 || 91111032Sjulian (td->td_flags & TDF_ASTPENDING) == 0)) 92102266Srwatson printf("failed to set signal flags properly for ast()\n"); 9393793Sbde mtx_unlock_spin(&sched_lock); 9482585Sdillon PROC_UNLOCK(p); 9593793Sbde#endif 9628013Sdyson 9793793Sbde /* 98104964Sjeff * Let the scheduler adjust our priority etc. 9993793Sbde */ 100104964Sjeff sched_userret(td); 10171527Sjhb 1026296Sdg /* 103105974Sjulian * We need to check to see if we have to exit or wait due to a 104105974Sjulian * single threading requirement or some other STOP condition. 105105974Sjulian * Don't bother doing all the work if the stop bits are not set 106105974Sjulian * at this time.. If we miss it, we miss it.. no big deal. 10799072Sjulian */ 108105974Sjulian if (P_SHOULDSTOP(p)) { 109105974Sjulian PROC_LOCK(p); 110105974Sjulian thread_suspend_check(0); /* Can suspend or kill */ 111105974Sjulian PROC_UNLOCK(p); 112105974Sjulian } 113105974Sjulian 114105974Sjulian /* 115105974Sjulian * Do special thread processing, e.g. upcall tweaking and such. 116105974Sjulian */ 117116361Sdavidxu if (p->p_flag & P_SA) { 118103838Sjulian thread_userret(td, frame); 11999072Sjulian } 120110190Sjulian 121110190Sjulian /* 122110190Sjulian * Charge system time if profiling. 123110190Sjulian */ 124113874Sjhb if (p->p_flag & P_PROFIL) { 125110190Sjulian quad_t ticks; 126110190Sjulian 127110190Sjulian mtx_lock_spin(&sched_lock); 128111024Sjeff ticks = td->td_sticks - oticks; 129110190Sjulian mtx_unlock_spin(&sched_lock); 130111032Sjulian addupc_task(td, TRAPF_PC(frame), (u_int)ticks * psratio); 131110190Sjulian } 1321690Sdg} 1331690Sdg 1344Srgrimes/* 13578983Sjhb * Process an asynchronous software trap. 13678983Sjhb * This is relatively easy. 13781493Sjhb * This function will return with preemption disabled. 1384Srgrimes */ 139798Swollmanvoid 14099072Sjulianast(struct trapframe *framep) 14165557Sjasone{ 142104297Sjhb struct thread *td; 143104297Sjhb struct proc *p; 144103838Sjulian struct kse *ke; 145104297Sjhb struct ksegrp *kg; 146125454Sjhb struct rlimit rlim; 14781493Sjhb u_int prticks, sticks; 14881493Sjhb int sflag; 14983366Sjulian int flags; 15093793Sbde int sig; 15177015Sbde#if defined(DEV_NPX) && !defined(SMP) 15277015Sbde int ucode; 15377015Sbde#endif 15465557Sjasone 155104297Sjhb td = curthread; 156104297Sjhb p = td->td_proc; 157104378Sjmallett kg = td->td_ksegrp; 158104378Sjmallett 15999072Sjulian CTR3(KTR_SYSC, "ast: thread %p (pid %d, %s)", td, p->p_pid, 16099072Sjulian p->p_comm); 16172911Sjhb KASSERT(TRAPF_USERMODE(framep), ("ast in kernel mode")); 162111883Sjhb WITNESS_WARN(WARN_PANIC, NULL, "Returning to user mode"); 16381493Sjhb mtx_assert(&Giant, MA_NOTOWNED); 16493793Sbde mtx_assert(&sched_lock, MA_NOTOWNED); 16593390Sjake td->td_frame = framep; 166104297Sjhb 16793390Sjake /* 16893390Sjake * This updates the p_sflag's for the checks below in one 16993390Sjake * "atomic" operation with turning off the astpending flag. 17093390Sjake * If another AST is triggered while we are handling the 17193390Sjake * AST's saved in sflag, the astpending flag will be set and 17293390Sjake * ast() will be called again. 17393390Sjake */ 17493390Sjake mtx_lock_spin(&sched_lock); 175104383Sjmallett ke = td->td_kse; 176111024Sjeff sticks = td->td_sticks; 177111032Sjulian flags = td->td_flags; 17893390Sjake sflag = p->p_sflag; 179112888Sjeff p->p_sflag &= ~(PS_ALRMPEND | PS_PROFPEND | PS_XCPU); 180106655Srwatson#ifdef MAC 181106655Srwatson p->p_sflag &= ~PS_MACPEND; 182106655Srwatson#endif 183112888Sjeff td->td_flags &= ~(TDF_ASTPENDING | TDF_NEEDSIGCHK | 184116963Sdavidxu TDF_NEEDRESCHED | TDF_OWEUPC | TDF_INTERRUPT); 18593390Sjake cnt.v_soft++; 186104297Sjhb prticks = 0; 187113874Sjhb if (flags & TDF_OWEUPC && p->p_flag & P_PROFIL) { 188110190Sjulian prticks = p->p_stats->p_prof.pr_ticks; 189110190Sjulian p->p_stats->p_prof.pr_ticks = 0; 19093390Sjake } 19193390Sjake mtx_unlock_spin(&sched_lock); 19299072Sjulian /* 19399072Sjulian * XXXKSE While the fact that we owe a user profiling 19499072Sjulian * tick is stored per KSE in this code, the statistics 19599072Sjulian * themselves are still stored per process. 19699072Sjulian * This should probably change, by which I mean that 19799072Sjulian * possibly the location of both might change. 19899072Sjulian */ 19991090Sjulian 20093390Sjake if (td->td_ucred != p->p_ucred) 20193390Sjake cred_update_thread(td); 202113874Sjhb if (flags & TDF_OWEUPC && p->p_flag & P_PROFIL) 203111032Sjulian addupc_task(td, p->p_stats->p_prof.pr_addr, prticks); 20493390Sjake if (sflag & PS_ALRMPEND) { 20593390Sjake PROC_LOCK(p); 20693390Sjake psignal(p, SIGVTALRM); 20793390Sjake PROC_UNLOCK(p); 20893390Sjake } 20977015Sbde#if defined(DEV_NPX) && !defined(SMP) 21093390Sjake if (PCPU_GET(curpcb)->pcb_flags & PCB_NPXTRAP) { 21193390Sjake atomic_clear_int(&PCPU_GET(curpcb)->pcb_flags, 21293390Sjake PCB_NPXTRAP); 21393390Sjake ucode = npxtrap(); 21493390Sjake if (ucode != -1) { 215112883Sjeff trapsignal(td, SIGFPE, ucode); 21677015Sbde } 21793390Sjake } 21877015Sbde#endif 21993390Sjake if (sflag & PS_PROFPEND) { 22093390Sjake PROC_LOCK(p); 22193390Sjake psignal(p, SIGPROF); 22293390Sjake PROC_UNLOCK(p); 22393390Sjake } 224104240Sjhb if (sflag & PS_XCPU) { 225104240Sjhb PROC_LOCK(p); 226125454Sjhb lim_rlimit(p, RLIMIT_CPU, &rlim); 227113636Sjhb mtx_lock_spin(&sched_lock); 228125454Sjhb if (p->p_runtime.sec >= rlim.rlim_max) { 229113636Sjhb mtx_unlock_spin(&sched_lock); 230104240Sjhb killproc(p, "exceeded maximum CPU limit"); 231113636Sjhb } else { 232125454Sjhb if (p->p_cpulimit < rlim.rlim_max) 233104719Sjhb p->p_cpulimit += 5; 234104719Sjhb mtx_unlock_spin(&sched_lock); 235113636Sjhb psignal(p, SIGXCPU); 236104240Sjhb } 237104240Sjhb PROC_UNLOCK(p); 238104240Sjhb } 239106655Srwatson#ifdef MAC 240106655Srwatson if (sflag & PS_MACPEND) 241106655Srwatson mac_thread_userret(td); 242106655Srwatson#endif 243111032Sjulian if (flags & TDF_NEEDRESCHED) { 244118240Speter#ifdef KTRACE 245118240Speter if (KTRPOINT(td, KTR_CSW)) 246119781Speter ktrcsw(1, 1); 247118240Speter#endif 24893793Sbde mtx_lock_spin(&sched_lock); 249104964Sjeff sched_prio(td, kg->kg_user_pri); 250124944Sjeff mi_switch(SW_INVOL); 25193793Sbde mtx_unlock_spin(&sched_lock); 252118240Speter#ifdef KTRACE 253118240Speter if (KTRPOINT(td, KTR_CSW)) 254119781Speter ktrcsw(0, 1); 255118240Speter#endif 25693793Sbde } 257112888Sjeff if (flags & TDF_NEEDSIGCHK) { 25893793Sbde PROC_LOCK(p); 259114983Sjhb mtx_lock(&p->p_sigacts->ps_mtx); 260116963Sdavidxu while ((sig = cursig(td)) != 0) 26193793Sbde postsig(sig); 262114983Sjhb mtx_unlock(&p->p_sigacts->ps_mtx); 26393793Sbde PROC_UNLOCK(p); 26493793Sbde } 26565557Sjasone 26693390Sjake userret(td, framep, sticks); 26799753Smini#ifdef DIAGNOSTIC 26899753Smini cred_free_thread(td); 26999753Smini#endif 27081493Sjhb mtx_assert(&Giant, MA_NOTOWNED); 27124691Speter} 272