WebSVN – HelenOS – Diff – /trunk/kernel/generic/src/synch/futex.c



 
#define FUTEX_HT_SIZE   1024    /* keep it a power of 2 */
 
static void futex_initialize(futex_t *futex);
 
static futex_t *futex_find(uintptr_t paddr);
static index_t futex_ht_hash(unative_t *key);
static bool futex_ht_compare(unative_t *key, count_t keys, link_t *item);
static void futex_ht_remove_callback(link_t *item);
 
/**
 * Read-write lock protecting global futex hash table.
 * It is also used to serialize access to all futex_t structures.

 * @param flags Select mode of operation.
 *
 * @return One of ESYNCH_TIMEOUT, ESYNCH_OK_ATOMIC and ESYNCH_OK_BLOCKED. See synch.h.
 *     If there is no physical mapping for uaddr ENOENT is returned.
 */
unative_t sys_futex_sleep_timeout(uintptr_t uaddr, uint32_t usec, int flags)
{
    futex_t *futex;
    uintptr_t paddr;
    pte_t *t;
    ipl_t ipl;
   
    ipl = interrupts_disable();
 

    page_table_lock(AS, true);
    t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE));
    if (!t || !PTE_VALID(t) || !PTE_PRESENT(t)) {
        page_table_unlock(AS, true);
        interrupts_restore(ipl);
        return (unative_t) ENOENT;
    }
    paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE));
    page_table_unlock(AS, true);
   
    interrupts_restore(ipl);   
 
    futex = futex_find(paddr);
   
    return (unative_t) waitq_sleep_timeout(&futex->wq, usec, flags | SYNCH_FLAGS_INTERRUPTIBLE);
}
 
/** Wakeup one thread waiting in futex wait queue.
 *
 * @param uaddr Userspace address of the futex counter.
 *
 * @return ENOENT if there is no physical mapping for uaddr.
 */
unative_t sys_futex_wakeup(uintptr_t uaddr)
{
    futex_t *futex;
    uintptr_t paddr;
    pte_t *t;
    ipl_t ipl;
   
    ipl = interrupts_disable();
   

    page_table_lock(AS, true);
    t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE));
    if (!t || !PTE_VALID(t) || !PTE_PRESENT(t)) {
        page_table_unlock(AS, true);
        interrupts_restore(ipl);
        return (unative_t) ENOENT;
    }
    paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE));
    page_table_unlock(AS, true);
   
    interrupts_restore(ipl);

 *
 * @param paddr Physical address of the userspace futex counter.
 *
 * @return Address of the kernel futex structure.
 */
futex_t *futex_find(uintptr_t paddr)
{
    link_t *item;
    futex_t *futex;
    btree_node_t *leaf;
   

 *
 * @param key Address where the key (i.e. physical address of futex counter) is stored.
 *
 * @return Index into futex hash table.
 */
index_t futex_ht_hash(unative_t *key)
{
    return *key & (FUTEX_HT_SIZE-1);
}
 
/** Compare futex hash table item with a key.
 *
 * @param key Address where the key (i.e. physical address of futex counter) is stored.
 *
 * @return True if the item matches the key. False otherwise.
 */
bool futex_ht_compare(unative_t *key, count_t keys, link_t *item)
{
    futex_t *futex;
 
    ASSERT(keys == 1);
 

        int i;
       
        node = list_get_instance(cur, btree_node_t, leaf_link);
        for (i = 0; i < node->keys; i++) {
            futex_t *ftx;
            uintptr_t paddr = node->key[i];
           
            ftx = (futex_t *) node->value[i];
            if (--ftx->refcount == 0)
                hash_table_remove(&futex_ht, &paddr, 1);
        }

Rev 1757	Rev 1780
Line 56...	Line 56...
56		56
57	#define FUTEX_HT_SIZE 1024 /* keep it a power of 2 */	57	#define FUTEX_HT_SIZE 1024 /* keep it a power of 2 */
58		58
59	static void futex_initialize(futex_t *futex);	59	static void futex_initialize(futex_t *futex);
60		60
61	static futex_t *futex_find(__address paddr);	61	static futex_t *futex_find(uintptr_t paddr);
62	static index_t futex_ht_hash(__native *key);	62	static index_t futex_ht_hash(unative_t *key);
63	static bool futex_ht_compare(__native key, count_t keys, link_t item);	63	static bool futex_ht_compare(unative_t key, count_t keys, link_t item);
64	static void futex_ht_remove_callback(link_t *item);	64	static void futex_ht_remove_callback(link_t *item);
65		65
66	/**	66	/**
67	* Read-write lock protecting global futex hash table.	67	* Read-write lock protecting global futex hash table.
68	* It is also used to serialize access to all futex_t structures.	68	* It is also used to serialize access to all futex_t structures.
Line 106...	Line 106...
106	* @param flags Select mode of operation.	106	* @param flags Select mode of operation.
107	*	107	*
108	* @return One of ESYNCH_TIMEOUT, ESYNCH_OK_ATOMIC and ESYNCH_OK_BLOCKED. See synch.h.	108	* @return One of ESYNCH_TIMEOUT, ESYNCH_OK_ATOMIC and ESYNCH_OK_BLOCKED. See synch.h.
109	* If there is no physical mapping for uaddr ENOENT is returned.	109	* If there is no physical mapping for uaddr ENOENT is returned.
110	*/	110	*/
111	__native sys_futex_sleep_timeout(__address uaddr, __u32 usec, int flags)	111	unative_t sys_futex_sleep_timeout(uintptr_t uaddr, uint32_t usec, int flags)
112	{	112	{
113	futex_t *futex;	113	futex_t *futex;
114	__address paddr;	114	uintptr_t paddr;
115	pte_t *t;	115	pte_t *t;
116	ipl_t ipl;	116	ipl_t ipl;
117		117
118	ipl = interrupts_disable();	118	ipl = interrupts_disable();
119		119
Line 123...	Line 123...
123	page_table_lock(AS, true);	123	page_table_lock(AS, true);
124	t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE));	124	t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE));
125	if (!t \|\| !PTE_VALID(t) \|\| !PTE_PRESENT(t)) {	125	if (!t \|\| !PTE_VALID(t) \|\| !PTE_PRESENT(t)) {
126	page_table_unlock(AS, true);	126	page_table_unlock(AS, true);
127	interrupts_restore(ipl);	127	interrupts_restore(ipl);
128	return (__native) ENOENT;	128	return (unative_t) ENOENT;
129	}	129	}
130	paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE));	130	paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE));
131	page_table_unlock(AS, true);	131	page_table_unlock(AS, true);
132		132
133	interrupts_restore(ipl);	133	interrupts_restore(ipl);
134		134
135	futex = futex_find(paddr);	135	futex = futex_find(paddr);
136		136
137	return (__native) waitq_sleep_timeout(&futex->wq, usec, flags \| SYNCH_FLAGS_INTERRUPTIBLE);	137	return (unative_t) waitq_sleep_timeout(&futex->wq, usec, flags \| SYNCH_FLAGS_INTERRUPTIBLE);
138	}	138	}
139		139
140	/** Wakeup one thread waiting in futex wait queue.	140	/** Wakeup one thread waiting in futex wait queue.
141	*	141	*
142	* @param uaddr Userspace address of the futex counter.	142	* @param uaddr Userspace address of the futex counter.
143	*	143	*
144	* @return ENOENT if there is no physical mapping for uaddr.	144	* @return ENOENT if there is no physical mapping for uaddr.
145	*/	145	*/
146	__native sys_futex_wakeup(__address uaddr)	146	unative_t sys_futex_wakeup(uintptr_t uaddr)
147	{	147	{
148	futex_t *futex;	148	futex_t *futex;
149	__address paddr;	149	uintptr_t paddr;
150	pte_t *t;	150	pte_t *t;
151	ipl_t ipl;	151	ipl_t ipl;
152		152
153	ipl = interrupts_disable();	153	ipl = interrupts_disable();
154		154
Line 158...	Line 158...
158	page_table_lock(AS, true);	158	page_table_lock(AS, true);
159	t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE));	159	t = page_mapping_find(AS, ALIGN_DOWN(uaddr, PAGE_SIZE));
160	if (!t \|\| !PTE_VALID(t) \|\| !PTE_PRESENT(t)) {	160	if (!t \|\| !PTE_VALID(t) \|\| !PTE_PRESENT(t)) {
161	page_table_unlock(AS, true);	161	page_table_unlock(AS, true);
162	interrupts_restore(ipl);	162	interrupts_restore(ipl);
163	return (__native) ENOENT;	163	return (unative_t) ENOENT;
164	}	164	}
165	paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE));	165	paddr = PTE_GET_FRAME(t) + (uaddr - ALIGN_DOWN(uaddr, PAGE_SIZE));
166	page_table_unlock(AS, true);	166	page_table_unlock(AS, true);
167		167
168	interrupts_restore(ipl);	168	interrupts_restore(ipl);
Line 180...	Line 180...
180	*	180	*
181	* @param paddr Physical address of the userspace futex counter.	181	* @param paddr Physical address of the userspace futex counter.
182	*	182	*
183	* @return Address of the kernel futex structure.	183	* @return Address of the kernel futex structure.
184	*/	184	*/
185	futex_t *futex_find(__address paddr)	185	futex_t *futex_find(uintptr_t paddr)
186	{	186	{
187	link_t *item;	187	link_t *item;
188	futex_t *futex;	188	futex_t *futex;
189	btree_node_t *leaf;	189	btree_node_t *leaf;
190		190
Line 273...	Line 273...
273	*	273	*
274	* @param key Address where the key (i.e. physical address of futex counter) is stored.	274	* @param key Address where the key (i.e. physical address of futex counter) is stored.
275	*	275	*
276	* @return Index into futex hash table.	276	* @return Index into futex hash table.
277	*/	277	*/
278	index_t futex_ht_hash(__native *key)	278	index_t futex_ht_hash(unative_t *key)
279	{	279	{
280	return *key & (FUTEX_HT_SIZE-1);	280	return *key & (FUTEX_HT_SIZE-1);
281	}	281	}
282		282
283	/** Compare futex hash table item with a key.	283	/** Compare futex hash table item with a key.
284	*	284	*
285	* @param key Address where the key (i.e. physical address of futex counter) is stored.	285	* @param key Address where the key (i.e. physical address of futex counter) is stored.
286	*	286	*
287	* @return True if the item matches the key. False otherwise.	287	* @return True if the item matches the key. False otherwise.
288	*/	288	*/
289	bool futex_ht_compare(__native key, count_t keys, link_t item)	289	bool futex_ht_compare(unative_t key, count_t keys, link_t item)
290	{	290	{
291	futex_t *futex;	291	futex_t *futex;
292		292
293	ASSERT(keys == 1);	293	ASSERT(keys == 1);
294		294
Line 321...	Line 321...
321	int i;	321	int i;
322		322
323	node = list_get_instance(cur, btree_node_t, leaf_link);	323	node = list_get_instance(cur, btree_node_t, leaf_link);
324	for (i = 0; i < node->keys; i++) {	324	for (i = 0; i < node->keys; i++) {
325	futex_t *ftx;	325	futex_t *ftx;
326	__address paddr = node->key[i];	326	uintptr_t paddr = node->key[i];
327		327
328	ftx = (futex_t *) node->value[i];	328	ftx = (futex_t *) node->value[i];
329	if (--ftx->refcount == 0)	329	if (--ftx->refcount == 0)
330	hash_table_remove(&futex_ht, &paddr, 1);	330	hash_table_remove(&futex_ht, &paddr, 1);
331	}	331	}

Subversion Repositories HelenOS

(root)/trunk/kernel/generic/src/synch/futex.c @ 2472 – Rev 1757 → 1780