ca971bbfd8
This patch changes the top-level directory layout as a preparatory step for improving the tools for managing 3rd-party source codes. The rationale is described in the issue referenced below. Issue #1082
63 lines
1.3 KiB
C++
63 lines
1.3 KiB
C++
/*
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* \brief Least-recently-used cache replacement strategy
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* \author Stefan Kalkowski
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* \date 2013-12-05
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*/
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/*
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* Copyright (C) 2013 Genode Labs GmbH
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*
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* This file is part of the Genode OS framework, which is distributed
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* under the terms of the GNU General Public License version 2.
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*/
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#include <base/printf.h>
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#include "lru.h"
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#include "driver.h"
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typedef Driver<Lru_policy>::Chunk_level_4 Chunk;
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static const Lru_policy::Element *lru = 0;
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static Genode::List<Lru_policy::Element> lru_list;
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static void lru_access(const Lru_policy::Element *e)
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{
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if (e == lru) return;
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if (e->next()) lru_list.remove(e);
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lru_list.insert(e, lru);
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lru = e;
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}
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void Lru_policy::read(const Lru_policy::Element *e) {
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lru_access(e); }
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void Lru_policy::write(const Lru_policy::Element *e) {
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lru_access(e); }
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void Lru_policy::flush(Cache::size_t size)
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{
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Cache::size_t s = 0;
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for (Lru_policy::Element *e = lru_list.first();
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e && ((size == 0) || (s < size));
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e = lru_list.first(), s += sizeof(Chunk)) {
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Chunk *cb = static_cast<Chunk*>(e);
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e = e->next();
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try {
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cb->free(Driver<Lru_policy>::CACHE_BLK_SIZE,
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cb->base_offset());
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lru_list.remove(cb);
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} catch(Chunk::Dirty_chunk &e) {
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cb->sync(e.size, e.off);
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}
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}
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if (!lru_list.first()) lru = 0;
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if (s < size) throw Block::Driver::Request_congestion();
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}
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