diff options
| -rw-r--r-- | mm/memory-failure.c | 132 |
1 files changed, 65 insertions, 67 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index a92874a98b60..3ac807c1f4f3 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -985,26 +985,73 @@ static int __get_hwpoison_page(struct page *page) return 0; } -static int get_hwpoison_page(struct page *p) +/* + * Safely get reference count of an arbitrary page. + * + * Returns 0 for a free page, 1 for an in-use page, + * -EIO for a page-type we cannot handle and -EBUSY if we raced with an + * allocation. + * We only incremented refcount in case the page was already in-use and it + * is a known type we can handle. + */ +static int get_any_page(struct page *p, unsigned long flags) { - int ret; - bool drained = false; + int ret = 0, pass = 0; + bool count_increased = false; -retry: - ret = __get_hwpoison_page(p); - if (!ret && !is_free_buddy_page(p) && !page_count(p) && !drained) { - /* - * The page might be in a pcplist, so try to drain those - * and see if we are lucky. - */ - drain_all_pages(page_zone(p)); - drained = true; - goto retry; + if (flags & MF_COUNT_INCREASED) + count_increased = true; + +try_again: + if (!count_increased && !__get_hwpoison_page(p)) { + if (page_count(p)) { + /* We raced with an allocation, retry. */ + if (pass++ < 3) + goto try_again; + ret = -EBUSY; + } else if (!PageHuge(p) && !is_free_buddy_page(p)) { + /* We raced with put_page, retry. */ + if (pass++ < 3) + goto try_again; + ret = -EIO; + } + } else { + if (PageHuge(p) || PageLRU(p) || __PageMovable(p)) { + ret = 1; + } else { + /* + * A page we cannot handle. Check whether we can turn + * it into something we can handle. + */ + if (pass++ < 3) { + put_page(p); + shake_page(p, 1); + count_increased = false; + goto try_again; + } + put_page(p); + ret = -EIO; + } } return ret; } +static int get_hwpoison_page(struct page *p, unsigned long flags, + enum mf_flags ctxt) +{ + int ret; + + zone_pcp_disable(page_zone(p)); + if (ctxt == MF_SOFT_OFFLINE) + ret = get_any_page(p, flags); + else + ret = __get_hwpoison_page(p); + zone_pcp_enable(page_zone(p)); + + return ret; +} + /* * Do all that is necessary to remove user space mappings. Unmap * the pages and send SIGBUS to the processes if the data was dirty. @@ -1185,7 +1232,7 @@ static int memory_failure_hugetlb(unsigned long pfn, int flags) num_poisoned_pages_inc(); - if (!(flags & MF_COUNT_INCREASED) && !get_hwpoison_page(p)) { + if (!(flags & MF_COUNT_INCREASED) && !get_hwpoison_page(p, flags, 0)) { /* * Check "filter hit" and "race with other subpage." */ @@ -1387,7 +1434,7 @@ try_again: * In fact it's dangerous to directly bump up page count from 0, * that may make page_ref_freeze()/page_ref_unfreeze() mismatch. */ - if (!(flags & MF_COUNT_INCREASED) && !get_hwpoison_page(p)) { + if (!(flags & MF_COUNT_INCREASED) && !get_hwpoison_page(p, flags, 0)) { if (is_free_buddy_page(p)) { if (take_page_off_buddy(p)) { page_ref_inc(p); @@ -1630,6 +1677,7 @@ int unpoison_memory(unsigned long pfn) struct page *page; struct page *p; int freeit = 0; + unsigned long flags = 0; static DEFINE_RATELIMIT_STATE(unpoison_rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); @@ -1674,7 +1722,7 @@ int unpoison_memory(unsigned long pfn) return 0; } - if (!get_hwpoison_page(p)) { + if (!get_hwpoison_page(p, flags, 0)) { if (TestClearPageHWPoison(p)) num_poisoned_pages_dec(); unpoison_pr_info("Unpoison: Software-unpoisoned free page %#lx\n", @@ -1705,56 +1753,6 @@ int unpoison_memory(unsigned long pfn) } EXPORT_SYMBOL(unpoison_memory); -/* - * Safely get reference count of an arbitrary page. - * Returns 0 for a free page, 1 for an in-use page, -EIO for a page-type we - * cannot handle and -EBUSY if we raced with an allocation. - * We only incremented refcount in case the page was already in-use and it is - * a known type we can handle. - */ -static int get_any_page(struct page *p, int flags) -{ - int ret = 0, pass = 0; - bool count_increased = false; - - if (flags & MF_COUNT_INCREASED) - count_increased = true; - -try_again: - if (!count_increased && !get_hwpoison_page(p)) { - if (page_count(p)) { - /* We raced with an allocation, retry. */ - if (pass++ < 3) - goto try_again; - ret = -EBUSY; - } else if (!PageHuge(p) && !is_free_buddy_page(p)) { - /* We raced with put_page, retry. */ - if (pass++ < 3) - goto try_again; - ret = -EIO; - } - } else { - if (PageHuge(p) || PageLRU(p) || __PageMovable(p)) { - ret = 1; - } else { - /* - * A page we cannot handle. Check whether we can turn - * it into something we can handle. - */ - if (pass++ < 3) { - put_page(p); - shake_page(p, 1); - count_increased = false; - goto try_again; - } - put_page(p); - ret = -EIO; - } - } - - return ret; -} - static bool isolate_page(struct page *page, struct list_head *pagelist) { bool isolated = false; @@ -1928,7 +1926,7 @@ int soft_offline_page(unsigned long pfn, int flags) retry: get_online_mems(); - ret = get_any_page(page, flags); + ret = get_hwpoison_page(page, flags, MF_SOFT_OFFLINE); put_online_mems(); if (ret > 0) { |