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Revamp the mthread library and update test59

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Before, the 'main thread' of a process was never taken into account anywhere in
the library, causing mutexes not to work properly (and consequently, neither
did the condition variables). For example, if the 'main thread' (that is, the
thread which is started at the beginning of a process; not a spawned thread by
the library) would lock a mutex, it wasn't actually locked.
This commit is contained in:
Thomas Veerman
2010-09-30 13:44:13 +00:00
parent 3736ce3f55
commit a7072a5e1c
11 changed files with 467 additions and 288 deletions
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lib/libmthread/condition.c
+45 -23
View File
@@ -1,12 +1,12 @@
#include <minix/mthread.h>
#include "proto.h"
#include "global.h"
#include "proto.h"
PRIVATE struct __mthread_cond *vc_front, *vc_rear;
FORWARD _PROTOTYPE( void mthread_cond_add, (mthread_cond_t *c) );
FORWARD _PROTOTYPE( void mthread_cond_remove, (mthread_cond_t *c) );
FORWARD _PROTOTYPE( int mthread_cond_valid, (mthread_cond_t *c) );
#define MAIN_COND mainthread.m_cond
/*===========================================================================*
* mthread_init_valid_conditions *
@@ -46,9 +46,10 @@ PUBLIC int mthread_cond_broadcast(cond)
mthread_cond_t *cond;
{
/* Signal all threads waiting for condition 'cond'. */
int i;
mthread_thread_t t;
mthread_tcb_t *tcb;
mthread_init(); /* Make sure mthreads is initialized */
mthread_init(); /* Make sure libmthread is initialized */
if(cond == NULL) {
errno = EINVAL;
@@ -60,9 +61,15 @@ mthread_cond_t *cond;
return(-1);
}
for (i = 0; i < no_threads; i++)
if (threads[i].m_state == CONDITION && threads[i].m_cond == *cond)
mthread_unsuspend(i);
tcb = mthread_find_tcb(MAIN_THREAD);
if (tcb->m_state == MS_CONDITION && tcb->m_cond == *cond)
mthread_unsuspend(MAIN_THREAD);
for (t = (mthread_thread_t) 0; t < no_threads; t++) {
tcb = mthread_find_tcb(t);
if (tcb->m_state == MS_CONDITION && tcb->m_cond == *cond)
mthread_unsuspend(t);
}
return(0);
}
@@ -75,9 +82,10 @@ PUBLIC int mthread_cond_destroy(cond)
mthread_cond_t *cond;
{
/* Destroy a condition variable. Make sure it's not in use */
int i;
mthread_thread_t t;
mthread_tcb_t *tcb;
mthread_init(); /* Make sure mthreads is initialized */
mthread_init(); /* Make sure libmthread is initialized */
if (cond == NULL) {
errno = EINVAL;
@@ -90,8 +98,15 @@ mthread_cond_t *cond;
}
/* Is another thread currently using this condition variable? */
for (i = 0; i < no_threads; i++) {
if (threads[i].m_state == CONDITION && threads[i].m_cond == *cond) {
tcb = mthread_find_tcb(MAIN_THREAD);
if (tcb->m_state == MS_CONDITION && tcb->m_cond == *cond) {
errno = EBUSY;
return(-1);
}
for (t = (mthread_thread_t) 0; t < no_threads; t++) {
tcb = mthread_find_tcb(t);
if(tcb->m_state == MS_CONDITION && tcb->m_cond == *cond){
errno = EBUSY;
return(-1);
}
@@ -116,7 +131,7 @@ mthread_condattr_t *cattr;
/* Initialize condition variable to a known state. cattr is ignored */
struct __mthread_cond *c;
mthread_init(); /* Make sure mthreads is initialized */
mthread_init(); /* Make sure libmthread is initialized */
if (cond == NULL) {
errno = EINVAL;
@@ -171,9 +186,10 @@ PUBLIC int mthread_cond_signal(cond)
mthread_cond_t *cond;
{
/* Signal a thread that condition 'cond' was met. Just a single thread. */
int i;
mthread_thread_t t;
mthread_tcb_t *tcb;
mthread_init(); /* Make sure mthreads is initialized */
mthread_init(); /* Make sure libmthread is initialized */
if(cond == NULL) {
errno = EINVAL;
@@ -185,9 +201,14 @@ mthread_cond_t *cond;
return(-1);
}
for (i = 0; i < no_threads; i++) {
if (threads[i].m_state == CONDITION && threads[i].m_cond == *cond) {
mthread_unsuspend(i);
tcb = mthread_find_tcb(MAIN_THREAD);
if (tcb->m_state == MS_CONDITION && tcb->m_cond == *cond)
mthread_unsuspend(MAIN_THREAD);
for (t = (mthread_thread_t) 0; t < no_threads; t++) {
tcb = mthread_find_tcb(t);
if(tcb->m_state == MS_CONDITION && tcb->m_cond == *cond){
mthread_unsuspend(t);
break;
}
}
@@ -226,7 +247,7 @@ PUBLIC int mthread_cond_verify(void)
{
/* Return true in case no condition variables are in use. */
mthread_init(); /* Make sure mthreads is initialized */
mthread_init(); /* Make sure libmthread is initialized */
return(vc_front == NULL);
}
@@ -241,10 +262,11 @@ mthread_cond_t *cond;
mthread_mutex_t *mutex;
{
/* Wait for a condition to be signaled */
mthread_tcb_t *tcb;
struct __mthread_cond *c;
struct __mthread_mutex *m;
mthread_init(); /* Make sure mthreads is initialized */
mthread_init(); /* Make sure libmthread is initialized */
if (cond == NULL || mutex == NULL) {
errno = EINVAL;
@@ -263,13 +285,13 @@ mthread_mutex_t *mutex;
if (mthread_mutex_unlock(mutex) != 0) /* Fails when we're not the owner */
return(-1);
threads[current_thread].m_cond = c; /* Register condition variable. */
mthread_suspend(CONDITION);
tcb = mthread_find_tcb(current_thread);
tcb->m_cond = c; /* Register condition variable. */
mthread_suspend(MS_CONDITION);
/* When execution returns here, the condition was met. Lock mutex again. */
c->mutex = NULL; /* Forget about this mutex */
threads[current_thread].m_cond = NULL; /* ... and condition var */
tcb->m_cond = NULL; /* ... and condition var */
if (mthread_mutex_lock(mutex) != 0)
return(-1);