d19ef81437
need for most calls to vm_page_busy(). Specifically, most calls to vm_page_busy() occur immediately prior to a call to vm_page_remove(). In such cases, the containing vm object is locked across both calls. Consequently, the setting of the vm page's PG_BUSY flag is not even visible to other threads that are following the synchronization protocol. This change (1) eliminates the calls to vm_page_busy() that immediately precede a call to vm_page_remove() or functions, such as vm_page_free() and vm_page_rename(), that call it and (2) relaxes the requirement in vm_page_remove() that the vm page's PG_BUSY flag is set. Now, the vm page's PG_BUSY flag is set only when the vm object lock is released while the vm page is still in transition. Typically, this is when it is undergoing I/O. |
||
|---|---|---|
| .. | ||
| central | ||
| compile | ||
| conf | ||
| creator | ||
| ebus | ||
| fhc | ||
| include | ||
| isa | ||
| pci | ||
| sbus | ||
| sparc64 | ||