From: Naoya Horiguchi n-horiguchi@ah.jp.nec.com
[ Upstream commit b37ff71cc626a0c1b5e098ff9a0b723815f6aaeb ]
We'd like to narrow down the error region in memory error on hugetlb pages. However, currently we set PageHWPoison flags on all subpages in the error hugepage and add # of subpages to num_hwpoison_pages, which doesn't fit our purpose.
So this patch changes the behavior and we only set PageHWPoison on the head page then increase num_hwpoison_pages only by 1. This is a preparation for narrow-down part which comes in later patches.
Link: http://lkml.kernel.org/r/1496305019-5493-4-git-send-email-n-horiguchi@ah.jp.... Signed-off-by: Naoya Horiguchi n-horiguchi@ah.jp.nec.com Cc: Michal Hocko mhocko@kernel.org Cc: "Aneesh Kumar K.V" aneesh.kumar@linux.vnet.ibm.com Cc: Anshuman Khandual khandual@linux.vnet.ibm.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/swapops.h | 9 ----- mm/memory-failure.c | 87 ++++++++++++----------------------------- 2 files changed, 24 insertions(+), 72 deletions(-)
diff --git a/include/linux/swapops.h b/include/linux/swapops.h index 5c3a5f3e7eec..c5ff7b217ee6 100644 --- a/include/linux/swapops.h +++ b/include/linux/swapops.h @@ -196,15 +196,6 @@ static inline void num_poisoned_pages_dec(void) atomic_long_dec(&num_poisoned_pages); }
-static inline void num_poisoned_pages_add(long num) -{ - atomic_long_add(num, &num_poisoned_pages); -} - -static inline void num_poisoned_pages_sub(long num) -{ - atomic_long_sub(num, &num_poisoned_pages); -} #else
static inline swp_entry_t make_hwpoison_entry(struct page *page) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index d6524dce43b2..ad156b42d2ad 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1010,22 +1010,6 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn, return ret; }
-static void set_page_hwpoison_huge_page(struct page *hpage) -{ - int i; - int nr_pages = 1 << compound_order(hpage); - for (i = 0; i < nr_pages; i++) - SetPageHWPoison(hpage + i); -} - -static void clear_page_hwpoison_huge_page(struct page *hpage) -{ - int i; - int nr_pages = 1 << compound_order(hpage); - for (i = 0; i < nr_pages; i++) - ClearPageHWPoison(hpage + i); -} - /** * memory_failure - Handle memory failure of a page. * @pfn: Page Number of the corrupted page @@ -1051,7 +1035,6 @@ int memory_failure(unsigned long pfn, int trapno, int flags) struct page *hpage; struct page *orig_head; int res; - unsigned int nr_pages; unsigned long page_flags;
if (!sysctl_memory_failure_recovery) @@ -1065,24 +1048,23 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
p = pfn_to_page(pfn); orig_head = hpage = compound_head(p); + + /* tmporary check code, to be updated in later patches */ + if (PageHuge(p)) { + if (TestSetPageHWPoison(hpage)) { + pr_err("Memory failure: %#lx: already hardware poisoned\n", pfn); + return 0; + } + goto tmp; + } if (TestSetPageHWPoison(p)) { pr_err("Memory failure: %#lx: already hardware poisoned\n", pfn); return 0; }
- /* - * Currently errors on hugetlbfs pages are measured in hugepage units, - * so nr_pages should be 1 << compound_order. OTOH when errors are on - * transparent hugepages, they are supposed to be split and error - * measurement is done in normal page units. So nr_pages should be one - * in this case. - */ - if (PageHuge(p)) - nr_pages = 1 << compound_order(hpage); - else /* normal page or thp */ - nr_pages = 1; - num_poisoned_pages_add(nr_pages); +tmp: + num_poisoned_pages_inc();
/* * We need/can do nothing about count=0 pages. @@ -1110,12 +1092,11 @@ int memory_failure(unsigned long pfn, int trapno, int flags) if (PageHWPoison(hpage)) { if ((hwpoison_filter(p) && TestClearPageHWPoison(p)) || (p != hpage && TestSetPageHWPoison(hpage))) { - num_poisoned_pages_sub(nr_pages); + num_poisoned_pages_dec(); unlock_page(hpage); return 0; } } - set_page_hwpoison_huge_page(hpage); res = dequeue_hwpoisoned_huge_page(hpage); action_result(pfn, MF_MSG_FREE_HUGE, res ? MF_IGNORED : MF_DELAYED); @@ -1138,7 +1119,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags) pr_err("Memory failure: %#lx: thp split failed\n", pfn); if (TestClearPageHWPoison(p)) - num_poisoned_pages_sub(nr_pages); + num_poisoned_pages_dec(); put_hwpoison_page(p); return -EBUSY; } @@ -1202,14 +1183,14 @@ int memory_failure(unsigned long pfn, int trapno, int flags) */ if (!PageHWPoison(p)) { pr_err("Memory failure: %#lx: just unpoisoned\n", pfn); - num_poisoned_pages_sub(nr_pages); + num_poisoned_pages_dec(); unlock_page(hpage); put_hwpoison_page(hpage); return 0; } if (hwpoison_filter(p)) { if (TestClearPageHWPoison(p)) - num_poisoned_pages_sub(nr_pages); + num_poisoned_pages_dec(); unlock_page(hpage); put_hwpoison_page(hpage); return 0; @@ -1228,14 +1209,6 @@ int memory_failure(unsigned long pfn, int trapno, int flags) put_hwpoison_page(hpage); return 0; } - /* - * Set PG_hwpoison on all pages in an error hugepage, - * because containment is done in hugepage unit for now. - * Since we have done TestSetPageHWPoison() for the head page with - * page lock held, we can safely set PG_hwpoison bits on tail pages. - */ - if (PageHuge(p)) - set_page_hwpoison_huge_page(hpage);
/* * It's very difficult to mess with pages currently under IO @@ -1407,7 +1380,6 @@ int unpoison_memory(unsigned long pfn) struct page *page; struct page *p; int freeit = 0; - unsigned int nr_pages; static DEFINE_RATELIMIT_STATE(unpoison_rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST);
@@ -1452,8 +1424,6 @@ int unpoison_memory(unsigned long pfn) return 0; }
- nr_pages = 1 << compound_order(page); - if (!get_hwpoison_page(p)) { /* * Since HWPoisoned hugepage should have non-zero refcount, @@ -1483,10 +1453,8 @@ int unpoison_memory(unsigned long pfn) if (TestClearPageHWPoison(page)) { unpoison_pr_info("Unpoison: Software-unpoisoned page %#lx\n", pfn, &unpoison_rs); - num_poisoned_pages_sub(nr_pages); + num_poisoned_pages_dec(); freeit = 1; - if (PageHuge(page)) - clear_page_hwpoison_huge_page(page); } unlock_page(page);
@@ -1612,14 +1580,10 @@ static int soft_offline_huge_page(struct page *page, int flags) ret = -EIO; } else { /* overcommit hugetlb page will be freed to buddy */ - if (PageHuge(page)) { - set_page_hwpoison_huge_page(hpage); + SetPageHWPoison(page); + if (PageHuge(page)) dequeue_hwpoisoned_huge_page(hpage); - num_poisoned_pages_add(1 << compound_order(hpage)); - } else { - SetPageHWPoison(page); - num_poisoned_pages_inc(); - } + num_poisoned_pages_inc(); } return ret; } @@ -1728,15 +1692,12 @@ static int soft_offline_in_use_page(struct page *page, int flags)
static void soft_offline_free_page(struct page *page) { - if (PageHuge(page)) { - struct page *hpage = compound_head(page); + struct page *head = compound_head(page);
- set_page_hwpoison_huge_page(hpage); - if (!dequeue_hwpoisoned_huge_page(hpage)) - num_poisoned_pages_add(1 << compound_order(hpage)); - } else { - if (!TestSetPageHWPoison(page)) - num_poisoned_pages_inc(); + if (!TestSetPageHWPoison(head)) { + num_poisoned_pages_inc(); + if (PageHuge(head)) + dequeue_hwpoisoned_huge_page(head); } }