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- Catch up to proc flag changes.

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- Add new fork_exit() and fork_return() MI C functions.
This commit is contained in:
jhb 2001-01-24 10:47:14 +00:00
parent fdd3fb7200
commit f739ee5728
1 changed files with 79 additions and 4 deletions
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83
sys/kern/kern_fork.c
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@ -51,10 +51,12 @@
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/syscall.h>
#include <sys/vnode.h>
#include <sys/acct.h>
#include <sys/ktr.h>
#include <sys/ktrace.h>
#include <sys/kthread.h>
#include <sys/unistd.h>
#include <sys/jail.h>
@ -273,7 +275,7 @@ fork1(p1, flags, procp)
p1->p_peers = newproc;
newproc->p_leader = p1->p_leader;
} else {
newproc->p_peers = 0;
newproc->p_peers = NULL;
newproc->p_leader = newproc;
}
@ -319,7 +321,7 @@ fork1(p1, flags, procp)
*/
p2 = LIST_FIRST(&allproc);
again:
for (; p2 != 0; p2 = LIST_NEXT(p2, p_list)) {
for (; p2 != NULL; p2 = LIST_NEXT(p2, p_list)) {
while (p2->p_pid == trypid ||
p2->p_pgrp->pg_id == trypid ||
p2->p_session->s_sid == trypid) {
@ -377,9 +379,12 @@ fork1(p1, flags, procp)
* Increase reference counts on shared objects.
* The p_stats and p_sigacts substructs are set in vm_fork.
*/
p2->p_flag = P_INMEM;
if (p1->p_flag & P_PROFIL)
p2->p_flag = 0;
mtx_enter(&sched_lock, MTX_SPIN);
p2->p_sflag = PS_INMEM;
if (p1->p_sflag & PS_PROFIL)
startprofclock(p2);
mtx_exit(&sched_lock, MTX_SPIN);
MALLOC(p2->p_cred, struct pcred *, sizeof(struct pcred),
M_SUBPROC, M_WAITOK);
bcopy(p1->p_cred, p2->p_cred, sizeof(*p2->p_cred));
@ -631,3 +636,73 @@ rm_at_fork(function)
}
return (0);
}
/*
* Handle the return of a child process from fork1(). This function
* is called from the MD fork_trampoline() entry point.
*/
void
fork_exit(callout, arg, frame)
void *callout(void *, struct trapframe *);
void *arg;
struct trapframe frame;
{
struct proc *p;
mtx_exit(&sched_lock, MTX_SPIN);
/*
* XXX: We really shouldn't have to do this.
*/
enable_intr();
#ifdef SMP
if (PCPU_GET(switchtime.tv_sec) == 0)
microuptime(PCPU_PTR(switchtime));
PCPU_SET(switchticks, ticks);
#endif
/*
* cpu_set_fork_handler intercepts this function call to
* have this call a non-return function to stay in kernel mode.
* initproc has its own fork handler, but it does return.
*/
(*callout)(arg, &frame);
/*
* Check if a kernel thread misbehaved and returned from its main
* function.
*/
p = CURPROC;
if (p->p_flag & P_KTHREAD) {
mtx_enter(&Giant, MTX_DEF);
printf("Kernel thread \"%s\" (pid %d) exited prematurely.\n",
p->p_comm, p->p_pid);
kthread_exit(0);
}
mtx_assert(&Giant, MA_NOTOWNED);
}
/*
* Simplified back end of syscall(), used when returning from fork()
* directly into user mode. Giant is not held on entry, and must not
* be held on return. This function is passed in to fork_exit() as the
* first parameter and is called when returning to a new userland process.
*/
void
fork_return(p, frame)
struct proc *p;
struct trapframe *frame;
{
userret(p, frame, 0);
#ifdef KTRACE
if (KTRPOINT(p, KTR_SYSRET)) {
if (!mtx_owned(&Giant))
mtx_enter(&Giant, MTX_DEF);
ktrsysret(p->p_tracep, SYS_fork, 0, 0);
}
#endif
if (mtx_owned(&Giant))
mtx_exit(&Giant, MTX_DEF);
mtx_assert(&Giant, MA_NOTOWNED);
}