kernel: mm: separate demand paging headers into its own file
This separates demand paging related headers into its own file instead of being stuffed inside the main kernel memory management header file. Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This commit is contained in:
Daniel Leung
Carles Cufí
parent
c972ef1a0f
commit
f12d49d7ef
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@ -3138,6 +3138,7 @@ Userspace:
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- include/zephyr/sys/mem_manage.h
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- include/zephyr/kernel/mm.h
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- include/zephyr/kernel/internal/mm.h
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- include/zephyr/kernel/mm/demand_paging.h
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labels:
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- "area: Userspace"
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@ -14,6 +14,7 @@
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#endif
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#include <zephyr/kernel/internal/mm.h>
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#include <zephyr/kernel/mm/demand_paging.h>
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/**
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* @brief Kernel Memory Management
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@ -69,46 +70,6 @@
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#include <stddef.h>
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#include <inttypes.h>
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struct k_mem_paging_stats_t {
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#ifdef CONFIG_DEMAND_PAGING_STATS
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struct {
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/** Number of page faults */
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unsigned long cnt;
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/** Number of page faults with IRQ locked */
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unsigned long irq_locked;
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/** Number of page faults with IRQ unlocked */
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unsigned long irq_unlocked;
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#ifndef CONFIG_DEMAND_PAGING_ALLOW_IRQ
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/** Number of page faults while in ISR */
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unsigned long in_isr;
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#endif
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} pagefaults;
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struct {
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/** Number of clean pages selected for eviction */
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unsigned long clean;
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/** Number of dirty pages selected for eviction */
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unsigned long dirty;
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} eviction;
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#endif /* CONFIG_DEMAND_PAGING_STATS */
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};
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struct k_mem_paging_histogram_t {
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#ifdef CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM
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/* Counts for each bin in timing histogram */
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unsigned long counts[CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM_NUM_BINS];
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/* Bounds for the bins in timing histogram,
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* excluding the first and last (hence, NUM_SLOTS - 1).
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*/
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unsigned long bounds[CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM_NUM_BINS];
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#endif /* CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM */
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};
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#ifdef __cplusplus
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extern "C" {
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#endif
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@ -222,304 +183,6 @@ void k_mem_unmap(void *addr, size_t size);
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size_t k_mem_region_align(uintptr_t *aligned_addr, size_t *aligned_size,
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uintptr_t addr, size_t size, size_t align);
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/**
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* @defgroup demand_paging Demand Paging
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* @ingroup kernel_memory_management
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*/
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/**
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* @defgroup mem-demand-paging Demand Paging APIs
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* @ingroup demand_paging
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* @{
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*/
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/**
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* Evict a page-aligned virtual memory region to the backing store
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*
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* Useful if it is known that a memory region will not be used for some time.
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* All the data pages within the specified region will be evicted to the
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* backing store if they weren't already, with their associated page frames
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* marked as available for mappings or page-ins.
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*
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* None of the associated page frames mapped to the provided region should
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* be pinned.
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*
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* Note that there are no guarantees how long these pages will be evicted,
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* they could take page faults immediately.
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*
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* If CONFIG_DEMAND_PAGING_ALLOW_IRQ is enabled, this function may not be
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* called by ISRs as the backing store may be in-use.
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*
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* @param addr Base page-aligned virtual address
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* @param size Page-aligned data region size
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* @retval 0 Success
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* @retval -ENOMEM Insufficient space in backing store to satisfy request.
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* The region may be partially paged out.
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*/
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int k_mem_page_out(void *addr, size_t size);
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/**
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* Load a virtual data region into memory
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*
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* After the function completes, all the page frames associated with this
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* function will be paged in. However, they are not guaranteed to stay there.
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* This is useful if the region is known to be used soon.
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*
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* If CONFIG_DEMAND_PAGING_ALLOW_IRQ is enabled, this function may not be
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* called by ISRs as the backing store may be in-use.
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*
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* @param addr Base page-aligned virtual address
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* @param size Page-aligned data region size
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*/
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void k_mem_page_in(void *addr, size_t size);
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/**
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* Pin an aligned virtual data region, paging in as necessary
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*
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* After the function completes, all the page frames associated with this
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* region will be resident in memory and pinned such that they stay that way.
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* This is a stronger version of z_mem_page_in().
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*
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* If CONFIG_DEMAND_PAGING_ALLOW_IRQ is enabled, this function may not be
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* called by ISRs as the backing store may be in-use.
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*
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* @param addr Base page-aligned virtual address
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* @param size Page-aligned data region size
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*/
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void k_mem_pin(void *addr, size_t size);
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/**
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* Un-pin an aligned virtual data region
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*
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* After the function completes, all the page frames associated with this
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* region will be no longer marked as pinned. This does not evict the region,
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* follow this with z_mem_page_out() if you need that.
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*
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* @param addr Base page-aligned virtual address
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* @param size Page-aligned data region size
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*/
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void k_mem_unpin(void *addr, size_t size);
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/**
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* Get the paging statistics since system startup
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*
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* This populates the paging statistics struct being passed in
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* as argument.
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*
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* @param[in,out] stats Paging statistics struct to be filled.
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*/
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__syscall void k_mem_paging_stats_get(struct k_mem_paging_stats_t *stats);
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struct k_thread;
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/**
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* Get the paging statistics since system startup for a thread
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*
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* This populates the paging statistics struct being passed in
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* as argument for a particular thread.
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*
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* @param[in] thread Thread
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* @param[in,out] stats Paging statistics struct to be filled.
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*/
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__syscall
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void k_mem_paging_thread_stats_get(struct k_thread *thread,
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struct k_mem_paging_stats_t *stats);
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/**
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* Get the eviction timing histogram
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*
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* This populates the timing histogram struct being passed in
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* as argument.
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*
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* @param[in,out] hist Timing histogram struct to be filled.
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*/
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__syscall void k_mem_paging_histogram_eviction_get(
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struct k_mem_paging_histogram_t *hist);
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/**
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* Get the backing store page-in timing histogram
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*
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* This populates the timing histogram struct being passed in
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* as argument.
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*
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* @param[in,out] hist Timing histogram struct to be filled.
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*/
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__syscall void k_mem_paging_histogram_backing_store_page_in_get(
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struct k_mem_paging_histogram_t *hist);
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/**
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* Get the backing store page-out timing histogram
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*
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* This populates the timing histogram struct being passed in
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* as argument.
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*
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* @param[in,out] hist Timing histogram struct to be filled.
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*/
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__syscall void k_mem_paging_histogram_backing_store_page_out_get(
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struct k_mem_paging_histogram_t *hist);
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#include <syscalls/mm.h>
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/** @} */
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/**
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* Eviction algorithm APIs
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*
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* @defgroup mem-demand-paging-eviction Eviction Algorithm APIs
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* @ingroup demand_paging
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* @{
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*/
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/**
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* Select a page frame for eviction
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*
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* The kernel will invoke this to choose a page frame to evict if there
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* are no free page frames.
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*
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* This function will never be called before the initial
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* k_mem_paging_eviction_init().
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*
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* This function is invoked with interrupts locked.
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*
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* @param [out] dirty Whether the page to evict is dirty
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* @return The page frame to evict
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*/
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struct z_page_frame *k_mem_paging_eviction_select(bool *dirty);
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/**
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* Initialization function
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*
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* Called at POST_KERNEL to perform any necessary initialization tasks for the
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* eviction algorithm. k_mem_paging_eviction_select() is guaranteed to never be
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* called until this has returned, and this will only be called once.
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*/
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void k_mem_paging_eviction_init(void);
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/** @} */
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/**
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* Backing store APIs
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*
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* @defgroup mem-demand-paging-backing-store Backing Store APIs
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* @ingroup demand_paging
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* @{
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*/
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/**
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* Reserve or fetch a storage location for a data page loaded into a page frame
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*
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* The returned location token must be unique to the mapped virtual address.
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* This location will be used in the backing store to page out data page
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* contents for later retrieval. The location value must be page-aligned.
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*
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* This function may be called multiple times on the same data page. If its
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* page frame has its Z_PAGE_FRAME_BACKED bit set, it is expected to return
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* the previous backing store location for the data page containing a cached
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* clean copy. This clean copy may be updated on page-out, or used to
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* discard clean pages without needing to write out their contents.
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*
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* If the backing store is full, some other backing store location which caches
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* a loaded data page may be selected, in which case its associated page frame
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* will have the Z_PAGE_FRAME_BACKED bit cleared (as it is no longer cached).
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*
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* pf->addr will indicate the virtual address the page is currently mapped to.
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* Large, sparse backing stores which can contain the entire address space
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* may simply generate location tokens purely as a function of pf->addr with no
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* other management necessary.
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*
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* This function distinguishes whether it was called on behalf of a page
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* fault. A free backing store location must always be reserved in order for
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* page faults to succeed. If the page_fault parameter is not set, this
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* function should return -ENOMEM even if one location is available.
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*
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* This function is invoked with interrupts locked.
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*
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* @param pf Virtual address to obtain a storage location
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* @param [out] location storage location token
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* @param page_fault Whether this request was for a page fault
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* @return 0 Success
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* @return -ENOMEM Backing store is full
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*/
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int k_mem_paging_backing_store_location_get(struct z_page_frame *pf,
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uintptr_t *location,
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bool page_fault);
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/**
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* Free a backing store location
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*
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* Any stored data may be discarded, and the location token associated with
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* this address may be re-used for some other data page.
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*
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* This function is invoked with interrupts locked.
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*
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* @param location Location token to free
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*/
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void k_mem_paging_backing_store_location_free(uintptr_t location);
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/**
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* Copy a data page from Z_SCRATCH_PAGE to the specified location
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*
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* Immediately before this is called, Z_SCRATCH_PAGE will be mapped read-write
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* to the intended source page frame for the calling context.
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*
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* Calls to this and k_mem_paging_backing_store_page_in() will always be
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* serialized, but interrupts may be enabled.
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*
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* @param location Location token for the data page, for later retrieval
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*/
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void k_mem_paging_backing_store_page_out(uintptr_t location);
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/**
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* Copy a data page from the provided location to Z_SCRATCH_PAGE.
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*
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* Immediately before this is called, Z_SCRATCH_PAGE will be mapped read-write
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* to the intended destination page frame for the calling context.
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*
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* Calls to this and k_mem_paging_backing_store_page_out() will always be
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* serialized, but interrupts may be enabled.
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*
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* @param location Location token for the data page
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*/
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void k_mem_paging_backing_store_page_in(uintptr_t location);
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/**
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* Update internal accounting after a page-in
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*
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* This is invoked after k_mem_paging_backing_store_page_in() and interrupts
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* have been* re-locked, making it safe to access the z_page_frame data.
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* The location value will be the same passed to
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* k_mem_paging_backing_store_page_in().
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*
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* The primary use-case for this is to update custom fields for the backing
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* store in the page frame, to reflect where the data should be evicted to
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* if it is paged out again. This may be a no-op in some implementations.
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*
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* If the backing store caches paged-in data pages, this is the appropriate
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* time to set the Z_PAGE_FRAME_BACKED bit. The kernel only skips paging
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* out clean data pages if they are noted as clean in the page tables and the
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* Z_PAGE_FRAME_BACKED bit is set in their associated page frame.
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*
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* @param pf Page frame that was loaded in
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* @param location Location of where the loaded data page was retrieved
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*/
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void k_mem_paging_backing_store_page_finalize(struct z_page_frame *pf,
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uintptr_t location);
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/**
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* Backing store initialization function.
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*
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* The implementation may expect to receive page in/out calls as soon as this
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* returns, but not before that. Called at POST_KERNEL.
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*
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* This function is expected to do two things:
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* - Initialize any internal data structures and accounting for the backing
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* store.
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* - If the backing store already contains all or some loaded kernel data pages
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* at boot time, Z_PAGE_FRAME_BACKED should be appropriately set for their
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* associated page frames, and any internal accounting set up appropriately.
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*/
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void k_mem_paging_backing_store_init(void);
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/** @} */
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#ifdef __cplusplus
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}
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#endif
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369
include/zephyr/kernel/mm/demand_paging.h
Normal file
369
include/zephyr/kernel/mm/demand_paging.h
Normal file
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@ -0,0 +1,369 @@
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/*
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* Copyright (c) 2020 Intel Corporation
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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#ifndef ZEPHYR_INCLUDE_KERNEL_MM_DEMAND_PAGING_H
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#define ZEPHYR_INCLUDE_KERNEL_MM_DEMAND_PAGING_H
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#include <zephyr/kernel/mm.h>
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#include <zephyr/sys/util.h>
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#include <zephyr/toolchain.h>
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/**
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* @defgroup demand_paging Demand Paging
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* @ingroup kernel_memory_management
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*/
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/**
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* @defgroup mem-demand-paging Demand Paging APIs
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* @ingroup demand_paging
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* @{
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*/
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#ifndef _ASMLANGUAGE
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#include <stdint.h>
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#include <stddef.h>
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#include <inttypes.h>
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#include <zephyr/sys/__assert.h>
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struct k_mem_paging_stats_t {
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#ifdef CONFIG_DEMAND_PAGING_STATS
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struct {
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/** Number of page faults */
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unsigned long cnt;
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/** Number of page faults with IRQ locked */
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unsigned long irq_locked;
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/** Number of page faults with IRQ unlocked */
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unsigned long irq_unlocked;
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#ifndef CONFIG_DEMAND_PAGING_ALLOW_IRQ
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/** Number of page faults while in ISR */
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unsigned long in_isr;
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#endif
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} pagefaults;
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struct {
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/** Number of clean pages selected for eviction */
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unsigned long clean;
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/** Number of dirty pages selected for eviction */
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unsigned long dirty;
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} eviction;
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#endif /* CONFIG_DEMAND_PAGING_STATS */
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};
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struct k_mem_paging_histogram_t {
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#ifdef CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM
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/* Counts for each bin in timing histogram */
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unsigned long counts[CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM_NUM_BINS];
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/* Bounds for the bins in timing histogram,
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* excluding the first and last (hence, NUM_SLOTS - 1).
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*/
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unsigned long bounds[CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM_NUM_BINS];
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#endif /* CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM */
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};
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#ifdef __cplusplus
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extern "C" {
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#endif
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/**
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* Evict a page-aligned virtual memory region to the backing store
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*
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* Useful if it is known that a memory region will not be used for some time.
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* All the data pages within the specified region will be evicted to the
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* backing store if they weren't already, with their associated page frames
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* marked as available for mappings or page-ins.
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*
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* None of the associated page frames mapped to the provided region should
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* be pinned.
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*
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* Note that there are no guarantees how long these pages will be evicted,
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* they could take page faults immediately.
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*
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* If CONFIG_DEMAND_PAGING_ALLOW_IRQ is enabled, this function may not be
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* called by ISRs as the backing store may be in-use.
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*
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* @param addr Base page-aligned virtual address
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* @param size Page-aligned data region size
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* @retval 0 Success
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* @retval -ENOMEM Insufficient space in backing store to satisfy request.
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* The region may be partially paged out.
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*/
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int k_mem_page_out(void *addr, size_t size);
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/**
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* Load a virtual data region into memory
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||||
*
|
||||
* After the function completes, all the page frames associated with this
|
||||
* function will be paged in. However, they are not guaranteed to stay there.
|
||||
* This is useful if the region is known to be used soon.
|
||||
*
|
||||
* If CONFIG_DEMAND_PAGING_ALLOW_IRQ is enabled, this function may not be
|
||||
* called by ISRs as the backing store may be in-use.
|
||||
*
|
||||
* @param addr Base page-aligned virtual address
|
||||
* @param size Page-aligned data region size
|
||||
*/
|
||||
void k_mem_page_in(void *addr, size_t size);
|
||||
|
||||
/**
|
||||
* Pin an aligned virtual data region, paging in as necessary
|
||||
*
|
||||
* After the function completes, all the page frames associated with this
|
||||
* region will be resident in memory and pinned such that they stay that way.
|
||||
* This is a stronger version of z_mem_page_in().
|
||||
*
|
||||
* If CONFIG_DEMAND_PAGING_ALLOW_IRQ is enabled, this function may not be
|
||||
* called by ISRs as the backing store may be in-use.
|
||||
*
|
||||
* @param addr Base page-aligned virtual address
|
||||
* @param size Page-aligned data region size
|
||||
*/
|
||||
void k_mem_pin(void *addr, size_t size);
|
||||
|
||||
/**
|
||||
* Un-pin an aligned virtual data region
|
||||
*
|
||||
* After the function completes, all the page frames associated with this
|
||||
* region will be no longer marked as pinned. This does not evict the region,
|
||||
* follow this with z_mem_page_out() if you need that.
|
||||
*
|
||||
* @param addr Base page-aligned virtual address
|
||||
* @param size Page-aligned data region size
|
||||
*/
|
||||
void k_mem_unpin(void *addr, size_t size);
|
||||
|
||||
/**
|
||||
* Get the paging statistics since system startup
|
||||
*
|
||||
* This populates the paging statistics struct being passed in
|
||||
* as argument.
|
||||
*
|
||||
* @param[in,out] stats Paging statistics struct to be filled.
|
||||
*/
|
||||
__syscall void k_mem_paging_stats_get(struct k_mem_paging_stats_t *stats);
|
||||
|
||||
struct k_thread;
|
||||
/**
|
||||
* Get the paging statistics since system startup for a thread
|
||||
*
|
||||
* This populates the paging statistics struct being passed in
|
||||
* as argument for a particular thread.
|
||||
*
|
||||
* @param[in] thread Thread
|
||||
* @param[in,out] stats Paging statistics struct to be filled.
|
||||
*/
|
||||
__syscall
|
||||
void k_mem_paging_thread_stats_get(struct k_thread *thread,
|
||||
struct k_mem_paging_stats_t *stats);
|
||||
|
||||
/**
|
||||
* Get the eviction timing histogram
|
||||
*
|
||||
* This populates the timing histogram struct being passed in
|
||||
* as argument.
|
||||
*
|
||||
* @param[in,out] hist Timing histogram struct to be filled.
|
||||
*/
|
||||
__syscall void k_mem_paging_histogram_eviction_get(
|
||||
struct k_mem_paging_histogram_t *hist);
|
||||
|
||||
/**
|
||||
* Get the backing store page-in timing histogram
|
||||
*
|
||||
* This populates the timing histogram struct being passed in
|
||||
* as argument.
|
||||
*
|
||||
* @param[in,out] hist Timing histogram struct to be filled.
|
||||
*/
|
||||
__syscall void k_mem_paging_histogram_backing_store_page_in_get(
|
||||
struct k_mem_paging_histogram_t *hist);
|
||||
|
||||
/**
|
||||
* Get the backing store page-out timing histogram
|
||||
*
|
||||
* This populates the timing histogram struct being passed in
|
||||
* as argument.
|
||||
*
|
||||
* @param[in,out] hist Timing histogram struct to be filled.
|
||||
*/
|
||||
__syscall void k_mem_paging_histogram_backing_store_page_out_get(
|
||||
struct k_mem_paging_histogram_t *hist);
|
||||
|
||||
#include <syscalls/demand_paging.h>
|
||||
|
||||
/** @} */
|
||||
|
||||
/**
|
||||
* Eviction algorithm APIs
|
||||
*
|
||||
* @defgroup mem-demand-paging-eviction Eviction Algorithm APIs
|
||||
* @ingroup demand_paging
|
||||
* @{
|
||||
*/
|
||||
|
||||
/**
|
||||
* Select a page frame for eviction
|
||||
*
|
||||
* The kernel will invoke this to choose a page frame to evict if there
|
||||
* are no free page frames.
|
||||
*
|
||||
* This function will never be called before the initial
|
||||
* k_mem_paging_eviction_init().
|
||||
*
|
||||
* This function is invoked with interrupts locked.
|
||||
*
|
||||
* @param [out] dirty Whether the page to evict is dirty
|
||||
* @return The page frame to evict
|
||||
*/
|
||||
struct z_page_frame *k_mem_paging_eviction_select(bool *dirty);
|
||||
|
||||
/**
|
||||
* Initialization function
|
||||
*
|
||||
* Called at POST_KERNEL to perform any necessary initialization tasks for the
|
||||
* eviction algorithm. k_mem_paging_eviction_select() is guaranteed to never be
|
||||
* called until this has returned, and this will only be called once.
|
||||
*/
|
||||
void k_mem_paging_eviction_init(void);
|
||||
|
||||
/** @} */
|
||||
|
||||
/**
|
||||
* Backing store APIs
|
||||
*
|
||||
* @defgroup mem-demand-paging-backing-store Backing Store APIs
|
||||
* @ingroup demand_paging
|
||||
* @{
|
||||
*/
|
||||
|
||||
/**
|
||||
* Reserve or fetch a storage location for a data page loaded into a page frame
|
||||
*
|
||||
* The returned location token must be unique to the mapped virtual address.
|
||||
* This location will be used in the backing store to page out data page
|
||||
* contents for later retrieval. The location value must be page-aligned.
|
||||
*
|
||||
* This function may be called multiple times on the same data page. If its
|
||||
* page frame has its Z_PAGE_FRAME_BACKED bit set, it is expected to return
|
||||
* the previous backing store location for the data page containing a cached
|
||||
* clean copy. This clean copy may be updated on page-out, or used to
|
||||
* discard clean pages without needing to write out their contents.
|
||||
*
|
||||
* If the backing store is full, some other backing store location which caches
|
||||
* a loaded data page may be selected, in which case its associated page frame
|
||||
* will have the Z_PAGE_FRAME_BACKED bit cleared (as it is no longer cached).
|
||||
*
|
||||
* pf->addr will indicate the virtual address the page is currently mapped to.
|
||||
* Large, sparse backing stores which can contain the entire address space
|
||||
* may simply generate location tokens purely as a function of pf->addr with no
|
||||
* other management necessary.
|
||||
*
|
||||
* This function distinguishes whether it was called on behalf of a page
|
||||
* fault. A free backing store location must always be reserved in order for
|
||||
* page faults to succeed. If the page_fault parameter is not set, this
|
||||
* function should return -ENOMEM even if one location is available.
|
||||
*
|
||||
* This function is invoked with interrupts locked.
|
||||
*
|
||||
* @param pf Virtual address to obtain a storage location
|
||||
* @param [out] location storage location token
|
||||
* @param page_fault Whether this request was for a page fault
|
||||
* @return 0 Success
|
||||
* @return -ENOMEM Backing store is full
|
||||
*/
|
||||
int k_mem_paging_backing_store_location_get(struct z_page_frame *pf,
|
||||
uintptr_t *location,
|
||||
bool page_fault);
|
||||
|
||||
/**
|
||||
* Free a backing store location
|
||||
*
|
||||
* Any stored data may be discarded, and the location token associated with
|
||||
* this address may be re-used for some other data page.
|
||||
*
|
||||
* This function is invoked with interrupts locked.
|
||||
*
|
||||
* @param location Location token to free
|
||||
*/
|
||||
void k_mem_paging_backing_store_location_free(uintptr_t location);
|
||||
|
||||
/**
|
||||
* Copy a data page from Z_SCRATCH_PAGE to the specified location
|
||||
*
|
||||
* Immediately before this is called, Z_SCRATCH_PAGE will be mapped read-write
|
||||
* to the intended source page frame for the calling context.
|
||||
*
|
||||
* Calls to this and k_mem_paging_backing_store_page_in() will always be
|
||||
* serialized, but interrupts may be enabled.
|
||||
*
|
||||
* @param location Location token for the data page, for later retrieval
|
||||
*/
|
||||
void k_mem_paging_backing_store_page_out(uintptr_t location);
|
||||
|
||||
/**
|
||||
* Copy a data page from the provided location to Z_SCRATCH_PAGE.
|
||||
*
|
||||
* Immediately before this is called, Z_SCRATCH_PAGE will be mapped read-write
|
||||
* to the intended destination page frame for the calling context.
|
||||
*
|
||||
* Calls to this and k_mem_paging_backing_store_page_out() will always be
|
||||
* serialized, but interrupts may be enabled.
|
||||
*
|
||||
* @param location Location token for the data page
|
||||
*/
|
||||
void k_mem_paging_backing_store_page_in(uintptr_t location);
|
||||
|
||||
/**
|
||||
* Update internal accounting after a page-in
|
||||
*
|
||||
* This is invoked after k_mem_paging_backing_store_page_in() and interrupts
|
||||
* have been* re-locked, making it safe to access the z_page_frame data.
|
||||
* The location value will be the same passed to
|
||||
* k_mem_paging_backing_store_page_in().
|
||||
*
|
||||
* The primary use-case for this is to update custom fields for the backing
|
||||
* store in the page frame, to reflect where the data should be evicted to
|
||||
* if it is paged out again. This may be a no-op in some implementations.
|
||||
*
|
||||
* If the backing store caches paged-in data pages, this is the appropriate
|
||||
* time to set the Z_PAGE_FRAME_BACKED bit. The kernel only skips paging
|
||||
* out clean data pages if they are noted as clean in the page tables and the
|
||||
* Z_PAGE_FRAME_BACKED bit is set in their associated page frame.
|
||||
*
|
||||
* @param pf Page frame that was loaded in
|
||||
* @param location Location of where the loaded data page was retrieved
|
||||
*/
|
||||
void k_mem_paging_backing_store_page_finalize(struct z_page_frame *pf,
|
||||
uintptr_t location);
|
||||
|
||||
/**
|
||||
* Backing store initialization function.
|
||||
*
|
||||
* The implementation may expect to receive page in/out calls as soon as this
|
||||
* returns, but not before that. Called at POST_KERNEL.
|
||||
*
|
||||
* This function is expected to do two things:
|
||||
* - Initialize any internal data structures and accounting for the backing
|
||||
* store.
|
||||
* - If the backing store already contains all or some loaded kernel data pages
|
||||
* at boot time, Z_PAGE_FRAME_BACKED should be appropriately set for their
|
||||
* associated page frames, and any internal accounting set up appropriately.
|
||||
*/
|
||||
void k_mem_paging_backing_store_init(void);
|
||||
|
||||
/** @} */
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* !_ASMLANGUAGE */
|
||||
#endif /* ZEPHYR_INCLUDE_KERNEL_MM_DEMAND_PAGING_H */
|
||||
|
|
@ -25,6 +25,11 @@ zephyr_syscall_header_ifdef(
|
|||
${ZEPHYR_BASE}/include/zephyr/sys/mem_manage.h
|
||||
)
|
||||
|
||||
zephyr_syscall_header_ifdef(
|
||||
CONFIG_DEMAND_PAGING
|
||||
${ZEPHYR_BASE}/include/zephyr/kernel/mm/demand_paging.h
|
||||
)
|
||||
|
||||
# If a pre-built static library containing kernel code exists in
|
||||
# this directory, libkernel.a, link it with the application code
|
||||
# instead of building from source.
|
||||
|
|
|
|||
Loading…
Reference in a new issue