[Haiku-commits] r26578 - in haiku/trunk: headers/private/kernel src/system/kernel/vm
axeld at BerliOS
axeld at mail.berlios.de
Wed Jul 23 17:45:41 CEST 2008
Author: axeld
Date: 2008-07-23 17:45:40 +0200 (Wed, 23 Jul 2008)
New Revision: 26578
ViewCVS: http://svn.berlios.de/viewcvs/haiku?rev=26578&view=rev
Modified:
haiku/trunk/headers/private/kernel/vm_types.h
haiku/trunk/src/system/kernel/vm/vm.cpp
haiku/trunk/src/system/kernel/vm/vm_address_space.cpp
Log:
* Replaced the simplistic semaphore based R/W lock in the vm_address_space with
the new rw_lock locking primitive.
Modified: haiku/trunk/headers/private/kernel/vm_types.h
===================================================================
--- haiku/trunk/headers/private/kernel/vm_types.h 2008-07-23 15:03:41 UTC (rev 26577)
+++ haiku/trunk/headers/private/kernel/vm_types.h 2008-07-23 15:45:40 UTC (rev 26578)
@@ -314,7 +314,7 @@
struct vm_address_space {
struct vm_area *areas;
struct vm_area *area_hint;
- sem_id sem;
+ rw_lock lock;
addr_t base;
addr_t size;
int32 change_count;
Modified: haiku/trunk/src/system/kernel/vm/vm.cpp
===================================================================
--- haiku/trunk/src/system/kernel/vm/vm.cpp 2008-07-23 15:03:41 UTC (rev 26577)
+++ haiku/trunk/src/system/kernel/vm/vm.cpp 2008-07-23 15:45:40 UTC (rev 26578)
@@ -271,7 +271,7 @@
if (fSpace == NULL)
return B_BAD_TEAM_ID;
- acquire_sem_etc(fSpace->sem, READ_COUNT, 0, 0);
+ rw_lock_read_lock(&fSpace->lock);
fLocked = true;
return B_OK;
}
@@ -282,7 +282,7 @@
AddressSpaceReadLocker::SetTo(vm_address_space* space)
{
fSpace = space;
- acquire_sem_etc(fSpace->sem, READ_COUNT, 0, 0);
+ rw_lock_read_lock(&fSpace->lock);
fLocked = true;
}
@@ -294,14 +294,14 @@
if (fSpace == NULL)
return B_BAD_TEAM_ID;
- acquire_sem_etc(fSpace->sem, READ_COUNT, 0, 0);
+ rw_lock_read_lock(&fSpace->lock);
acquire_sem_etc(sAreaHashLock, READ_COUNT, 0, 0);
area = (vm_area *)hash_lookup(sAreaHash, &areaID);
release_sem_etc(sAreaHashLock, READ_COUNT, 0);
if (area == NULL || area->address_space != fSpace) {
- release_sem_etc(fSpace->sem, READ_COUNT, 0);
+ rw_lock_read_unlock(&fSpace->lock);
return B_BAD_VALUE;
}
@@ -314,7 +314,7 @@
AddressSpaceReadLocker::Unlock()
{
if (fLocked) {
- release_sem_etc(fSpace->sem, READ_COUNT, 0);
+ rw_lock_read_unlock(&fSpace->lock);
fLocked = false;
}
}
@@ -364,7 +364,7 @@
if (fSpace == NULL)
return B_BAD_TEAM_ID;
- acquire_sem_etc(fSpace->sem, WRITE_COUNT, 0, 0);
+ rw_lock_write_lock(&fSpace->lock);
fLocked = true;
return B_OK;
}
@@ -377,14 +377,14 @@
if (fSpace == NULL)
return B_BAD_VALUE;
- acquire_sem_etc(fSpace->sem, WRITE_COUNT, 0, 0);
+ rw_lock_write_lock(&fSpace->lock);
acquire_sem_etc(sAreaHashLock, READ_COUNT, 0, 0);
area = (vm_area*)hash_lookup(sAreaHash, &areaID);
release_sem_etc(sAreaHashLock, READ_COUNT, 0);
if (area == NULL || area->address_space != fSpace) {
- release_sem_etc(fSpace->sem, WRITE_COUNT, 0);
+ rw_lock_write_unlock(&fSpace->lock);
return B_BAD_VALUE;
}
@@ -415,14 +415,14 @@
// Second try to get the area -- this time with the address space
// write lock held
- acquire_sem_etc(fSpace->sem, WRITE_COUNT, 0, 0);
+ rw_lock_write_lock(&fSpace->lock);
acquire_sem_etc(sAreaHashLock, READ_COUNT, 0, 0);
area = (vm_area *)hash_lookup(sAreaHash, &areaID);
release_sem_etc(sAreaHashLock, READ_COUNT, 0);
if (area == NULL) {
- release_sem_etc(fSpace->sem, WRITE_COUNT, 0);
+ rw_lock_write_unlock(&fSpace->lock);
return B_BAD_VALUE;
}
@@ -443,7 +443,10 @@
AddressSpaceWriteLocker::Unlock()
{
if (fLocked) {
- release_sem_etc(fSpace->sem, fDegraded ? READ_COUNT : WRITE_COUNT, 0);
+ if (fDegraded)
+ rw_lock_read_unlock(&fSpace->lock);
+ else
+ rw_lock_write_unlock(&fSpace->lock);
fLocked = false;
fDegraded = false;
}
@@ -453,7 +456,9 @@
void
AddressSpaceWriteLocker::DegradeToReadLock()
{
- release_sem_etc(fSpace->sem, WRITE_COUNT - READ_COUNT, 0);
+ // TODO: the current R/W lock implementation just keeps the write lock here
+ rw_lock_read_lock(&fSpace->lock);
+ rw_lock_write_unlock(&fSpace->lock);
fDegraded = true;
}
@@ -586,12 +591,18 @@
qsort(fItems, fCount, sizeof(lock_item), &_CompareItems);
for (int32 i = 0; i < fCount; i++) {
- status_t status = acquire_sem_etc(fItems[i].space->sem,
- fItems[i].write_lock ? WRITE_COUNT : READ_COUNT, 0, 0);
+ status_t status;
+ if (fItems[i].write_lock)
+ status = rw_lock_write_lock(&fItems[i].space->lock);
+ else
+ status = rw_lock_read_lock(&fItems[i].space->lock);
+
if (status < B_OK) {
while (--i >= 0) {
- release_sem_etc(fItems[i].space->sem,
- fItems[i].write_lock ? WRITE_COUNT : READ_COUNT, 0);
+ if (fItems[i].write_lock)
+ rw_lock_write_unlock(&fItems[i].space->lock);
+ else
+ rw_lock_read_unlock(&fItems[i].space->lock);
}
return status;
}
@@ -609,8 +620,10 @@
return;
for (int32 i = 0; i < fCount; i++) {
- release_sem_etc(fItems[i].space->sem,
- fItems[i].write_lock ? WRITE_COUNT : READ_COUNT, 0);
+ if (fItems[i].write_lock)
+ rw_lock_write_unlock(&fItems[i].space->lock);
+ else
+ rw_lock_read_unlock(&fItems[i].space->lock);
}
fLocked = false;
@@ -3416,7 +3429,7 @@
TRACE(("vm_delete_areas: called on address space 0x%lx\n",
addressSpace->id));
- acquire_sem_etc(addressSpace->sem, WRITE_COUNT, 0, 0);
+ rw_lock_write_lock(&addressSpace->lock);
// remove all reserved areas in this address space
@@ -3445,7 +3458,7 @@
delete_area(addressSpace, area);
}
- release_sem_etc(addressSpace->sem, WRITE_COUNT, 0);
+ rw_lock_write_unlock(&addressSpace->lock);
return B_OK;
}
@@ -3976,7 +3989,7 @@
vm_address_space *addressSpace = vm_get_current_user_address_space();
vm_area *area;
- acquire_sem_etc(addressSpace->sem, READ_COUNT, 0, 0);
+ rw_lock_read_lock(&addressSpace->lock);
// TODO: The user_memcpy() below can cause a deadlock, if it causes a page
// fault and someone is already waiting for a write lock on the same address
// space. This thread will then try to acquire the semaphore again and will
@@ -4038,7 +4051,7 @@
}
#endif // 0 (stack trace)
- release_sem_etc(addressSpace->sem, READ_COUNT, 0);
+ rw_lock_read_unlock(&addressSpace->lock);
vm_put_address_space(addressSpace);
#endif
struct thread *thread = thread_get_current_thread();
@@ -4756,7 +4769,7 @@
test_lock_memory(vm_address_space *addressSpace, addr_t address,
bool &needsLocking)
{
- acquire_sem_etc(addressSpace->sem, READ_COUNT, 0, 0);
+ rw_lock_read_lock(&addressSpace->lock);
vm_area *area = vm_area_lookup(addressSpace, address);
if (area != NULL) {
@@ -4767,7 +4780,7 @@
&& area->wiring != B_CONTIGUOUS;
}
- release_sem_etc(addressSpace->sem, READ_COUNT, 0);
+ rw_lock_read_unlock(&addressSpace->lock);
if (area == NULL)
return B_BAD_ADDRESS;
Modified: haiku/trunk/src/system/kernel/vm/vm_address_space.cpp
===================================================================
--- haiku/trunk/src/system/kernel/vm/vm_address_space.cpp 2008-07-23 15:03:41 UTC (rev 26577)
+++ haiku/trunk/src/system/kernel/vm/vm_address_space.cpp 2008-07-23 15:45:40 UTC (rev 26578)
@@ -31,7 +31,7 @@
#define ASPACE_HASH_TABLE_SIZE 1024
static struct hash_table *sAddressSpaceTable;
-static sem_id sAddressSpaceHashSem;
+static rw_lock sAddressSpaceTableLock;
static void
@@ -47,7 +47,6 @@
dprintf("base: 0x%lx\n", aspace->base);
dprintf("size: 0x%lx\n", aspace->size);
dprintf("change_count: 0x%lx\n", aspace->change_count);
- dprintf("sem: 0x%lx\n", aspace->sem);
dprintf("area_hint: %p\n", aspace->area_hint);
dprintf("area_list:\n");
for (area = aspace->areas; area != NULL; area = area->address_space_next) {
@@ -154,9 +153,11 @@
if (addressSpace == sKernelAddressSpace)
panic("tried to delete the kernel aspace!\n");
- acquire_sem_etc(addressSpace->sem, WRITE_COUNT, 0, 0);
- (*addressSpace->translation_map.ops->destroy)(&addressSpace->translation_map);
- delete_sem(addressSpace->sem);
+ rw_lock_write_lock(&addressSpace->lock);
+
+ addressSpace->translation_map.ops->destroy(&addressSpace->translation_map);
+
+ rw_lock_destroy(&addressSpace->lock);
free(addressSpace);
}
@@ -169,11 +170,11 @@
{
vm_address_space *addressSpace;
- acquire_sem_etc(sAddressSpaceHashSem, READ_COUNT, 0, 0);
+ rw_lock_read_lock(&sAddressSpaceTableLock);
addressSpace = (vm_address_space *)hash_lookup(sAddressSpaceTable, &id);
if (addressSpace)
atomic_add(&addressSpace->ref_count, 1);
- release_sem_etc(sAddressSpaceHashSem, READ_COUNT, 0);
+ rw_lock_read_unlock(&sAddressSpaceTableLock);
return addressSpace;
}
@@ -236,12 +237,12 @@
{
bool remove = false;
- acquire_sem_etc(sAddressSpaceHashSem, WRITE_COUNT, 0, 0);
+ rw_lock_write_lock(&sAddressSpaceTableLock);
if (atomic_add(&addressSpace->ref_count, -1) == 1) {
hash_remove(sAddressSpaceTable, addressSpace);
remove = true;
}
- release_sem_etc(sAddressSpaceHashSem, WRITE_COUNT, 0);
+ rw_lock_write_unlock(&sAddressSpaceTableLock);
if (remove)
delete_address_space(addressSpace);
@@ -258,9 +259,9 @@
void
vm_delete_address_space(vm_address_space *addressSpace)
{
- acquire_sem_etc(addressSpace->sem, WRITE_COUNT, 0, 0);
+ rw_lock_write_lock(&addressSpace->lock);
addressSpace->state = VM_ASPACE_STATE_DELETION;
- release_sem_etc(addressSpace->sem, WRITE_COUNT, 0);
+ rw_lock_write_unlock(&addressSpace->lock);
vm_delete_areas(addressSpace);
vm_put_address_space(addressSpace);
@@ -286,15 +287,8 @@
addressSpace->areas = NULL;
addressSpace->area_hint = NULL;
addressSpace->change_count = 0;
- if (!kernel) {
- // the kernel address space will create its semaphore later
- addressSpace->sem = create_sem(WRITE_COUNT, "address space");
- if (addressSpace->sem < B_OK) {
- status_t status = addressSpace->sem;
- free(addressSpace);
- return status;
- }
- }
+ rw_lock_init(&addressSpace->lock,
+ kernel ? "kernel address space" : "address space");
addressSpace->id = id;
addressSpace->ref_count = 1;
@@ -310,9 +304,9 @@
}
// add the aspace to the global hash table
- acquire_sem_etc(sAddressSpaceHashSem, WRITE_COUNT, 0, 0);
+ rw_lock_write_lock(&sAddressSpaceTableLock);
hash_insert(sAddressSpaceTable, addressSpace);
- release_sem_etc(sAddressSpaceHashSem, WRITE_COUNT, 0);
+ rw_lock_write_unlock(&sAddressSpaceTableLock);
*_addressSpace = addressSpace;
return B_OK;
@@ -322,7 +316,7 @@
status_t
vm_address_space_init(void)
{
- sAddressSpaceHashSem = -1;
+ rw_lock_init(&sAddressSpaceTableLock, "address spaces table");
// create the area and address space hash tables
{
@@ -334,8 +328,6 @@
panic("vm_init: error creating aspace hash table\n");
}
- sKernelAddressSpace = NULL;
-
// create the initial kernel address space
if (vm_create_address_space(1, KERNEL_BASE, KERNEL_SIZE,
true, &sKernelAddressSpace) != B_OK)
@@ -358,14 +350,5 @@
if (status < B_OK)
return status;
- status = sKernelAddressSpace->sem = create_sem(WRITE_COUNT,
- "kernel_aspacelock");
- if (status < B_OK)
- return status;
-
- status = sAddressSpaceHashSem = create_sem(WRITE_COUNT, "aspace_hash_sem");
- if (status < B_OK)
- return status;
-
return B_OK;
}
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