diff options
Diffstat (limited to 'src/lib9')
| -rw-r--r-- | src/lib9/9proc.h | 4 | ||||
| -rw-r--r-- | src/lib9/ffork-Linux.c | 201 | ||||
| -rw-r--r-- | src/lib9/mkfile | 1 | ||||
| -rw-r--r-- | src/lib9/qlock.c | 20 | ||||
| -rw-r--r-- | src/lib9/rendez-Linux.c | 59 | ||||
| -rw-r--r-- | src/lib9/rendez-pthread.c | 173 | ||||
| -rw-r--r-- | src/lib9/rendez-signal.c | 199 |
7 files changed, 124 insertions, 533 deletions
diff --git a/src/lib9/9proc.h b/src/lib9/9proc.h index 1f471b6f..0eb5f410 100644 --- a/src/lib9/9proc.h +++ b/src/lib9/9proc.h @@ -1,3 +1,6 @@ +#ifndef _9PROC_H_ +#define _9PROC_H_ 1 + enum { NPRIV = 16, @@ -20,3 +23,4 @@ extern Uproc *_p9uproc(int); extern void _p9uprocdie(void); extern void _clearuproc(void); +#endif diff --git a/src/lib9/ffork-Linux.c b/src/lib9/ffork-Linux.c index 4f976359..5dbd75cf 100644 --- a/src/lib9/ffork-Linux.c +++ b/src/lib9/ffork-Linux.c @@ -1,197 +1,32 @@ +#define ffork ffork_clone +#define getfforkid getfforkid_clone +#include "ffork-Linux-clone.c" +#undef ffork +#undef getfforkid + +#define ffork ffork_pthread +#define getfforkid getfforkid_pthread #include "ffork-pthread.c" +#undef ffork +#undef getfforkid -#ifdef OLD -/* - * Is nothing simple? - * - * We can't free the stack until we've finished executing, - * but once we've finished executing, we can't do anything - * at all, including call free. So instead we keep a linked list - * of all stacks for all processes, and every few times we try - * to allocate a new stack we scan the current stack list for - * dead processes and reclaim those stacks. - */ - -#include <u.h> -#include <sys/types.h> -#include <sys/wait.h> -#include <sched.h> -#include <signal.h> -#include <errno.h> -#include <libc.h> -#include "9proc.h" - -int fforkstacksize = 16384; - -typedef struct Stack Stack; -struct Stack -{ - Stack *next; - Stack *fnext; - int pid; -}; - -static Lock stacklock; -static Stack *freestacks; -static Stack *allstacks; -static int stackmallocs; -static void gc(void); - -static void* -mallocstack(void) -{ - Stack *p; - - lock(&stacklock); -top: - p = freestacks; - if(p) - freestacks = p->fnext; - else{ - if(stackmallocs++%1 == 0) - gc(); - if(freestacks) - goto top; - p = malloc(fforkstacksize); - p->next = allstacks; - allstacks = p; - } - if(p) - p->pid = 1; - unlock(&stacklock); - return p; -} - -static void -gc(void) -{ - Stack *p; - - for(p=allstacks; p; p=p->next){ - if(p->pid > 1) - if(kill(p->pid, 0) < 0 && errno == ESRCH){ - if(0) fprint(2, "reclaim stack from %d\n", p->pid); - p->pid = 0; - } - if(p->pid == 0){ - p->fnext = freestacks; - freestacks = p; - } - } -} - -static void -freestack(void *v) -{ - Stack *p; - - p = v; - if(p == nil) - return; - lock(&stacklock); - p->fnext = freestacks; - p->pid = 0; - freestacks = p; - unlock(&stacklock); - return; -} - -static int -tramp(void *v) -{ - void (*fn)(void*), *arg; - void **v2; - void *p; - - _p9uproc(0); - v2 = v; - fn = v2[0]; - arg = v2[1]; - p = v2[2]; - free(v2); - fn(arg); - _exit(0); - return 0; -} - -static int -trampnowait(void *v) -{ - int pid; - int cloneflag; - void **v2; - int *pidp; - void *p; - - v2 = v; - cloneflag = (int)v2[4]; - pidp = v2[3]; - p = v2[2]; - pid = clone(tramp, p+fforkstacksize-512, cloneflag, v); - *pidp = pid; - _exit(0); - return 0; -} +extern int _islinuxnptl(void); int ffork(int flags, void (*fn)(void*), void *arg) { - void **v; - char *p; - int cloneflag, pid, thepid, status, nowait; - - _p9uproc(0); - p = mallocstack(); - v = malloc(sizeof(void*)*5); - if(p==nil || v==nil){ - freestack(p); - free(v); - return -1; - } - cloneflag = 0; - flags &= ~RFPROC; - if(flags&RFMEM){ - cloneflag |= CLONE_VM; - flags &= ~RFMEM; - } - if(!(flags&RFFDG)) - cloneflag |= CLONE_FILES; + if(_islinuxnptl()) + return ffork_pthread(flags, fn, arg); else - flags &= ~RFFDG; - nowait = flags&RFNOWAIT; - if(!(flags&RFNOWAIT)) - cloneflag |= SIGCHLD; - else - flags &= ~RFNOWAIT; - if(flags){ - fprint(2, "unknown rfork flags %x\n", flags); - freestack(p); - free(v); - return -1; - } - v[0] = fn; - v[1] = arg; - v[2] = p; - v[3] = &thepid; - v[4] = (void*)cloneflag; - thepid = -1; - pid = clone(nowait ? trampnowait : tramp, p+fforkstacksize-16, cloneflag, v); - if(pid > 0 && nowait){ - if(wait4(pid, &status, __WALL, 0) < 0) - fprint(2, "ffork wait4: %r\n"); - }else - thepid = pid; - if(thepid == -1) - freestack(p); - else - ((Stack*)p)->pid = thepid; - return thepid; + return ffork_clone(flags, fn, arg); } int getfforkid(void) { - return getpid(); + if(_islinuxnptl()) + return getfforkid_pthread(); + else + return getfforkid_clone(); } -#endif diff --git a/src/lib9/mkfile b/src/lib9/mkfile index 7ade5b63..ed430ff8 100644 --- a/src/lib9/mkfile +++ b/src/lib9/mkfile @@ -141,7 +141,6 @@ LIB9OFILES=\ strecpy.$O\ sysfatal.$O\ sysname.$O\ - tas-$OBJTYPE.$O\ time.$O\ tokenize.$O\ truerand.$O\ diff --git a/src/lib9/qlock.c b/src/lib9/qlock.c index 798b08f3..625c100f 100644 --- a/src/lib9/qlock.c +++ b/src/lib9/qlock.c @@ -375,23 +375,3 @@ rwakeupall(Rendez *r) ; return i; } - -void -_procsleep(_Procrend *rend) -{ -//print("sleep %p %d\n", rend, getpid()); - pthread_cond_init(&rend->cond, 0); - rend->asleep = 1; - while(rend->asleep) - pthread_cond_wait(&rend->cond, &rend->l->mutex); - pthread_cond_destroy(&rend->cond); -} - -void -_procwakeup(_Procrend *rend) -{ -//print("wakeup %p\n", rend); - rend->asleep = 0; - pthread_cond_signal(&rend->cond); -} - diff --git a/src/lib9/rendez-Linux.c b/src/lib9/rendez-Linux.c index 673818e0..6d479310 100644 --- a/src/lib9/rendez-Linux.c +++ b/src/lib9/rendez-Linux.c @@ -1,3 +1,60 @@ -/* Could use futex(2) here instead of signals? */ +/* + * On Linux 2.6 and later, we can use pthreads (in fact, we must), + * but on earlier Linux, pthreads are incompatible with using our + * own coroutines in libthread. In order to make binaries that work + * on either system, we detect the pthread library in use and call + * the appropriate functions. + */ +#include <u.h> +#include <signal.h> +#include <pthread.h> +#include <libc.h> + +#define _procsleep _procsleep_signal +#define _procwakeup _procwakeup_signal #include "rendez-signal.c" + +#undef _procsleep +#undef _procwakeup +#define _procsleep _procsleep_pthread +#define _procwakeup _procwakeup_pthread +#include "rendez-pthread.c" + +#undef _procsleep +#undef _procwakeup + +int +_islinuxnptl(void) +{ + static char buf[100]; + static int isnptl = -1; + + if(isnptl == -1){ + if(confstr(_CS_GNU_LIBPTHREAD_VERSION, buf, sizeof buf) > 0 + && strncmp(buf, "NPTL", 4) == 0) + isnptl = 1; + else + isnptl = 0; + } + return isnptl; +} + +void +_procsleep(_Procrend *r) +{ + if(_islinuxnptl()) + return _procsleep_pthread(r); + else + return _procsleep_signal(r); +} + +void +_procwakeup(_Procrend *r) +{ + if(_islinuxnptl()) + return _procwakeup_pthread(r); + else + return _procwakeup_signal(r); +} + diff --git a/src/lib9/rendez-pthread.c b/src/lib9/rendez-pthread.c index fe930cef..2d08e0c3 100644 --- a/src/lib9/rendez-pthread.c +++ b/src/lib9/rendez-pthread.c @@ -1,170 +1,23 @@ -/* - NAME - rendezvous - user level process synchronization - - SYNOPSIS - ulong rendezvous(ulong tag, ulong value) - - DESCRIPTION - The rendezvous system call allows two processes to synchro- - nize and exchange a value. In conjunction with the shared - memory system calls (see segattach(2) and fork(2)), it - enables parallel programs to control their scheduling. - - Two processes wishing to synchronize call rendezvous with a - common tag, typically an address in memory they share. One - process will arrive at the rendezvous first; it suspends - execution until a second arrives. When a second process - meets the rendezvous the value arguments are exchanged - between the processes and returned as the result of the - respective rendezvous system calls. Both processes are - awakened when the rendezvous succeeds. - - The set of tag values which two processes may use to - rendezvous-their tag space-is inherited when a process - forks, unless RFREND is set in the argument to rfork; see - fork(2). - - If a rendezvous is interrupted the return value is ~0, so - that value should not be used in normal communication. - - * This assumes we're using pthreads and simulates rendezvous using - * shared memory and mutexes. - */ - #include <u.h> #include <pthread.h> -#include <signal.h> #include <libc.h> -enum +void +_procsleep(_Procrend *rend) { - VOUSHASH = 257, -}; - -typedef struct Vous Vous; -struct Vous -{ - Vous *link; - Lock lk; - ulong val; - ulong tag; - pthread_mutex_t mutex; -}; - -static void -ign(int x) -{ - USED(x); +//print("sleep %p %d\n", rend, getpid()); + pthread_cond_init(&rend->cond, 0); + rend->asleep = 1; + while(rend->asleep) + pthread_cond_wait(&rend->cond, &rend->l->mutex); + pthread_cond_destroy(&rend->cond); } -void /*__attribute__((constructor))*/ -ignusr1(void) +void +_procwakeup(_Procrend *rend) { - signal(SIGUSR1, ign); -} - -static Vous vouspool[2048]; -static int nvousused; -static Vous *vousfree; -static Vous *voushash[VOUSHASH]; -static Lock vouslock; - -static Vous* -getvous(void) -{ - Vous *v; - - if(vousfree){ - v = vousfree; - vousfree = v->link; - }else if(nvousused < nelem(vouspool)){ - v = &vouspool[nvousused++]; - pthread_mutex_init(&v->mutex, NULL); - }else - abort(); - return v; -} - -static void -putvous(Vous *v) -{ - lock(&vouslock); - v->link = vousfree; - vousfree = v; - unlock(&vouslock); -} - -static Vous* -findvous(ulong tag, ulong val, int *found) -{ - int h; - Vous *v, **l; - - lock(&vouslock); - h = tag%VOUSHASH; - for(l=&voushash[h], v=*l; v; l=&(*l)->link, v=*l){ - if(v->tag == tag){ - *l = v->link; - *found = 1; - unlock(&vouslock); - return v; - } - } - v = getvous(); - v->link = voushash[h]; - v->val = val; - v->tag = tag; - lock(&v->lk); - voushash[h] = v; - unlock(&vouslock); - *found = 0; - return v; -} - -#define DBG 0 -ulong -rendezvous(ulong tag, ulong val) -{ - int found; - ulong rval; - Vous *v; - - v = findvous(tag, val, &found); - if(!found){ - if(DBG)fprint(2, "tag %lux, sleeping on %p\n", tag, v); - /* - * No rendezvous partner was found; the next guy - * through will find v and wake us, so we must go - * to sleep. Do this by locking the mutex (it is - * unlocked) and then locking it again (our waker will - * unlock it for us). - */ - if(pthread_mutex_lock(&v->mutex) != 0) - abort(); - unlock(&v->lk); - if(pthread_mutex_lock(&v->mutex) != 0) - abort(); - rval = v->val; - pthread_mutex_unlock(&v->mutex); - if(DBG)fprint(2, " awake on %p\n", v); - unlock(&v->lk); - putvous(v); - }else{ - /* - * Found someone to meet. Wake him: - * - * A. lock v->lk (waits for him to lock the mutex once. - * B. unlock the mutex (wakes him up) - */ - if(DBG)fprint(2, "found tag %lux on %p, waking\n", tag, v); - lock(&v->lk); - rval = v->val; - v->val = val; - if(pthread_mutex_unlock(&v->mutex) != 0) - abort(); - /* lock passes to him */ - } - return rval; +//print("wakeup %p\n", rend); + rend->asleep = 0; + pthread_cond_signal(&rend->cond); } diff --git a/src/lib9/rendez-signal.c b/src/lib9/rendez-signal.c index 5709dd76..e2abc3d3 100644 --- a/src/lib9/rendez-signal.c +++ b/src/lib9/rendez-signal.c @@ -1,58 +1,9 @@ -/* - NAME - rendezvous - user level process synchronization - - SYNOPSIS - ulong rendezvous(ulong tag, ulong value) - - DESCRIPTION - The rendezvous system call allows two processes to synchro- - nize and exchange a value. In conjunction with the shared - memory system calls (see segattach(2) and fork(2)), it - enables parallel programs to control their scheduling. - - Two processes wishing to synchronize call rendezvous with a - common tag, typically an address in memory they share. One - process will arrive at the rendezvous first; it suspends - execution until a second arrives. When a second process - meets the rendezvous the value arguments are exchanged - between the processes and returned as the result of the - respective rendezvous system calls. Both processes are - awakened when the rendezvous succeeds. - - The set of tag values which two processes may use to - rendezvous-their tag space-is inherited when a process - forks, unless RFREND is set in the argument to rfork; see - fork(2). - - If a rendezvous is interrupted the return value is ~0, so - that value should not be used in normal communication. - - * This simulates rendezvous with shared memory, sigsuspend, and SIGUSR1. - */ - #include <u.h> #include <signal.h> #include <libc.h> #define DBG 0 -enum -{ - VOUSHASH = 257, -}; - -typedef struct Vous Vous; -struct Vous -{ - Vous *link; - int pid; - int wokeup; - ulong tag; - ulong val1; /* value for the sleeper */ - ulong val2; /* value for the waker */ -}; - static void ign(int x) { @@ -73,128 +24,40 @@ ignusr1(int restart) sigaction(SIGUSR1, &sa, nil); } -static Vous vouspool[2048]; -static int nvousused; -static Vous *vousfree; -static Vous *voushash[VOUSHASH]; -static Lock vouslock; - -static Vous* -getvous(void) -{ - Vous *v; - - if(vousfree){ - v = vousfree; - vousfree = v->link; - }else if(nvousused < nelem(vouspool)) - v = &vouspool[nvousused++]; - else{ - fprint(2, "rendezvous: out of vous!\n"); - abort(); - } - return v; -} - -static void -putvous(Vous *v) -{ - v->link = vousfree; - vousfree = v; -} - -static Vous* -findvous(ulong tag) -{ - int h; - Vous *v, **l; - - h = tag%VOUSHASH; - for(l=&voushash[h], v=*l; v; l=&(*l)->link, v=*l){ - if(v->tag == tag){ - *l = v->link; - v->link = nil; - return v; - } - } - return nil; -} - -static Vous* -mkvous(ulong tag) +void +_procsleep(_Procrend *r) { - Vous *v; - int h; + sigset_t mask; - h = tag%VOUSHASH; - v = getvous(); - v->link = voushash[h]; - v->tag = tag; - voushash[h] = v; - return v; + /* + * Go to sleep. + * + * Block USR1, set the handler to interrupt system calls, + * unlock the vouslock so our waker can wake us, + * and then suspend. + */ + r->asleep = 1; + r->pid = getpid(); + + sigprocmask(SIG_SETMASK, nil, &mask); + sigaddset(&mask, SIGUSR1); + sigprocmask(SIG_SETMASK, &mask, nil); + ignusr1(0); + unlock(r->l); + sigdelset(&mask, SIGUSR1); + sigsuspend(&mask); + + /* + * We're awake. Make USR1 not interrupt system calls. + */ + ignusr1(1); + assert(r->asleep == 0); } -ulong -rendezvous(ulong tag, ulong val) +void +_procwakeup(_Procrend *r) { - int vpid, pid; - ulong rval; - Vous *v; - sigset_t mask; - - pid = getpid(); - lock(&vouslock); - if((v = findvous(tag)) == nil){ - /* - * Go to sleep. - * - * Block USR1, set the handler to interrupt system calls, - * unlock the vouslock so our waker can wake us, - * and then suspend. - */ - v = mkvous(tag); - v->pid = pid; - v->val2 = val; - v->wokeup = 0; - sigprocmask(SIG_SETMASK, nil, &mask); - sigaddset(&mask, SIGUSR1); - sigprocmask(SIG_SETMASK, &mask, nil); - ignusr1(0); - if(DBG) fprint(2, "%d rv(%lux, %lux) -> s\n", pid, tag, val); - unlock(&vouslock); - sigdelset(&mask, SIGUSR1); - sigsuspend(&mask); - - /* - * We're awake. Make USR1 not interrupt system calls. - * Were we awakened or interrupted? - */ - ignusr1(1); - lock(&vouslock); - if(v->wokeup){ - rval = v->val1; - if(DBG) fprint(2, "%d rv(%lux, %lux) -> g %lux\n", pid, tag, val, rval); - }else{ - if(findvous(tag) != v){ - fprint(2, "rendezvous: interrupted but not found in hash table\n"); - abort(); - } - rval = ~(ulong)0; - if(DBG) fprint(2, "%d rv(%lux, %lux) -> g i\n", pid, tag, val); - } - putvous(v); - unlock(&vouslock); - }else{ - /* - * Wake up sleeper. - */ - rval = v->val2; - v->val1 = val; - vpid = v->pid; - v->wokeup = 1; - if(DBG) fprint(2, "%d rv(%lux, %lux) -> g %lux, w %d\n", pid, tag, val, rval, vpid); - unlock(&vouslock); - kill(vpid, SIGUSR1); - } - return rval; + r->asleep = 0; + assert(r->pid >= 1); + kill(r->pid, SIGUSR1); } |