cregit-Linux how code gets into the kernel

Release 4.8 mm/balloon_compaction.c

Directory: mm
 * mm/balloon_compaction.c
 * Common interface for making balloon pages movable by compaction.
 * Copyright (C) 2012, Red Hat, Inc.  Rafael Aquini <>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/balloon_compaction.h>

 * balloon_page_enqueue - allocates a new page and inserts it into the balloon
 *                        page list.
 * @b_dev_info: balloon device descriptor where we will insert a new page to
 * Driver must call it to properly allocate a new enlisted balloon page
 * before definitively removing it from the guest system.
 * This function returns the page address for the recently enqueued page or
 * NULL in the case we fail to allocate a new page this turn.

struct page *balloon_page_enqueue(struct balloon_dev_info *b_dev_info) { unsigned long flags; struct page *page = alloc_page(balloon_mapping_gfp_mask() | __GFP_NOMEMALLOC | __GFP_NORETRY); if (!page) return NULL; /* * Block others from accessing the 'page' when we get around to * establishing additional references. We should be the only one * holding a reference to the 'page' at this point. */ BUG_ON(!trylock_page(page)); spin_lock_irqsave(&b_dev_info->pages_lock, flags); balloon_page_insert(b_dev_info, page); __count_vm_event(BALLOON_INFLATE); spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); unlock_page(page); return page; }


rafael aquinirafael aquini8393.26%133.33%
konstantin khlebnikovkonstantin khlebnikov66.74%266.67%

EXPORT_SYMBOL_GPL(balloon_page_enqueue); /* * balloon_page_dequeue - removes a page from balloon's page list and returns * the its address to allow the driver release the page. * @b_dev_info: balloon device decriptor where we will grab a page from. * * Driver must call it to properly de-allocate a previous enlisted balloon page * before definetively releasing it back to the guest system. * This function returns the page address for the recently dequeued page or * NULL in the case we find balloon's page list temporarily empty due to * compaction isolated pages. */
struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) { struct page *page, *tmp; unsigned long flags; bool dequeued_page; dequeued_page = false; spin_lock_irqsave(&b_dev_info->pages_lock, flags); list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { /* * Block others from accessing the 'page' while we get around * establishing additional references and preparing the 'page' * to be released by the balloon driver. */ if (trylock_page(page)) { #ifdef CONFIG_BALLOON_COMPACTION if (PageIsolated(page)) { /* raced with isolation */ unlock_page(page); continue; } #endif balloon_page_delete(page); __count_vm_event(BALLOON_DEFLATE); unlock_page(page); dequeued_page = true; break; } } spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); if (!dequeued_page) { /* * If we are unable to dequeue a balloon page because the page * list is empty and there is no isolated pages, then something * went out of track and some balloon pages are lost. * BUG() here, otherwise the balloon driver may get stuck into * an infinite loop while attempting to release all its pages. */ spin_lock_irqsave(&b_dev_info->pages_lock, flags); if (unlikely(list_empty(&b_dev_info->pages) && !b_dev_info->isolated_pages)) BUG(); spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); page = NULL; } return page; }


rafael aquinirafael aquini12472.94%116.67%
konstantin khlebnikovkonstantin khlebnikov2514.71%350.00%
minchan kimminchan kim2112.35%233.33%

bool balloon_page_isolate(struct page *page, isolate_mode_t mode) { struct balloon_dev_info *b_dev_info = balloon_page_device(page); unsigned long flags; spin_lock_irqsave(&b_dev_info->pages_lock, flags); list_del(&page->lru); b_dev_info->isolated_pages++; spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); return true; }


rafael aquinirafael aquini5282.54%133.33%
minchan kimminchan kim812.70%133.33%
konstantin khlebnikovkonstantin khlebnikov34.76%133.33%

void balloon_page_putback(struct page *page) { struct balloon_dev_info *b_dev_info = balloon_page_device(page); unsigned long flags; spin_lock_irqsave(&b_dev_info->pages_lock, flags); list_add(&page->lru, &b_dev_info->pages); b_dev_info->isolated_pages--; spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); }


rafael aquinirafael aquini5893.55%133.33%
konstantin khlebnikovkonstantin khlebnikov34.84%133.33%
minchan kimminchan kim11.61%133.33%

/* move_to_new_page() counterpart for a ballooned page */
int balloon_page_migrate(struct address_space *mapping, struct page *newpage, struct page *page, enum migrate_mode mode) { struct balloon_dev_info *balloon = balloon_page_device(page); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(!PageLocked(newpage), newpage); return balloon->migratepage(balloon, newpage, page, mode); }


rafael aquinirafael aquini3955.71%125.00%
hugh dickinshugh dickins1521.43%125.00%
konstantin khlebnikovkonstantin khlebnikov1115.71%125.00%
minchan kimminchan kim57.14%125.00%

const struct address_space_operations balloon_aops = { .migratepage = balloon_page_migrate, .isolate_page = balloon_page_isolate, .putback_page = balloon_page_putback, }; EXPORT_SYMBOL_GPL(balloon_aops); #endif /* CONFIG_BALLOON_COMPACTION */

Overall Contributors

rafael aquinirafael aquini38775.44%111.11%
minchan kimminchan kim6212.09%222.22%
konstantin khlebnikovkonstantin khlebnikov489.36%444.44%
hugh dickinshugh dickins152.92%111.11%
bogdan sikorabogdan sikora10.19%111.11%
Directory: mm
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.