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/* IBM_PROLOG_BEGIN_TAG */
/* This is an automatically generated prolog. */
/* */
/* $Source: src/usr/trace/bufferpage.C $ */
/* */
/* IBM CONFIDENTIAL */
/* */
/* COPYRIGHT International Business Machines Corp. 2012 */
/* */
/* p1 */
/* */
/* Object Code Only (OCO) source materials */
/* Licensed Internal Code Source Materials */
/* IBM HostBoot Licensed Internal Code */
/* */
/* The source code for this program is not published or otherwise */
/* divested of its trade secrets, irrespective of what has been */
/* deposited with the U.S. Copyright Office. */
/* */
/* Origin: 30 */
/* */
/* IBM_PROLOG_END_TAG */
#include "bufferpage.H"
#include <limits.h>
#include <stdlib.h>
#include <kernel/pagemgr.H>
namespace TRACE
{
Entry* BufferPage::claimEntry(size_t i_size)
{
uint64_t l_usedSize = this->usedSize;
// Verify there is enough space.
while ((usedSize + i_size) < (PAGESIZE - sizeof(BufferPage)))
{
// Atomically attempt to claim i_size worth.
uint64_t newSize = l_usedSize + i_size;
if (!__sync_bool_compare_and_swap(&this->usedSize,
l_usedSize,
newSize))
{
// Failed race to atomically update.
// Re-read size, try again.
l_usedSize = this->usedSize;
continue;
}
// Successful at claiming an entry, return pointer to it.
return reinterpret_cast<Entry*>(&this->data[0] + l_usedSize);
}
return NULL;
}
BufferPage* BufferPage::allocate(bool i_common)
{
BufferPage* page = NULL;
page = reinterpret_cast<BufferPage*>(PageManager::allocatePage());
memset(page, '\0', PAGESIZE);
if (i_common)
{
page->commonPage = 1;
}
return page;
}
void BufferPage::deallocate(BufferPage* i_page)
{
PageManager::freePage(i_page);
}
}
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