X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=mm%2Fpage_owner.c;h=ac3d8d129974398cb98bf0bbf2b56207fdc18642;hb=643ad15d47410d37d43daf3ef1c8ac52c281efa5;hp=983c3a10fa07058df249c64d5c89b9578661f672;hpb=8f6c5b079cb37f01463a643182815c00aa5263f2;p=cascardo%2Flinux.git diff --git a/mm/page_owner.c b/mm/page_owner.c index 983c3a10fa07..ac3d8d129974 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -5,10 +5,12 @@ #include #include #include +#include +#include #include "internal.h" static bool page_owner_disabled = true; -bool page_owner_inited __read_mostly; +DEFINE_STATIC_KEY_FALSE(page_owner_inited); static void init_early_allocated_pages(void); @@ -37,7 +39,7 @@ static void init_page_owner(void) if (page_owner_disabled) return; - page_owner_inited = true; + static_branch_enable(&page_owner_inited); init_early_allocated_pages(); } @@ -72,10 +74,18 @@ void __set_page_owner(struct page *page, unsigned int order, gfp_t gfp_mask) page_ext->order = order; page_ext->gfp_mask = gfp_mask; page_ext->nr_entries = trace.nr_entries; + page_ext->last_migrate_reason = -1; __set_bit(PAGE_EXT_OWNER, &page_ext->flags); } +void __set_page_owner_migrate_reason(struct page *page, int reason) +{ + struct page_ext *page_ext = lookup_page_ext(page); + + page_ext->last_migrate_reason = reason; +} + gfp_t __get_page_owner_gfp(struct page *page) { struct page_ext *page_ext = lookup_page_ext(page); @@ -83,6 +93,31 @@ gfp_t __get_page_owner_gfp(struct page *page) return page_ext->gfp_mask; } +void __copy_page_owner(struct page *oldpage, struct page *newpage) +{ + struct page_ext *old_ext = lookup_page_ext(oldpage); + struct page_ext *new_ext = lookup_page_ext(newpage); + int i; + + new_ext->order = old_ext->order; + new_ext->gfp_mask = old_ext->gfp_mask; + new_ext->nr_entries = old_ext->nr_entries; + + for (i = 0; i < ARRAY_SIZE(new_ext->trace_entries); i++) + new_ext->trace_entries[i] = old_ext->trace_entries[i]; + + /* + * We don't clear the bit on the oldpage as it's going to be freed + * after migration. Until then, the info can be useful in case of + * a bug, and the overal stats will be off a bit only temporarily. + * Also, migrate_misplaced_transhuge_page() can still fail the + * migration and then we want the oldpage to retain the info. But + * in that case we also don't need to explicitly clear the info from + * the new page, which will be freed. + */ + __set_bit(PAGE_EXT_OWNER, &new_ext->flags); +} + static ssize_t print_page_owner(char __user *buf, size_t count, unsigned long pfn, struct page *page, struct page_ext *page_ext) @@ -100,8 +135,9 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn, return -ENOMEM; ret = snprintf(kbuf, count, - "Page allocated via order %u, mask 0x%x\n", - page_ext->order, page_ext->gfp_mask); + "Page allocated via order %u, mask %#x(%pGg)\n", + page_ext->order, page_ext->gfp_mask, + &page_ext->gfp_mask); if (ret >= count) goto err; @@ -110,23 +146,12 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn, pageblock_mt = get_pfnblock_migratetype(page, pfn); page_mt = gfpflags_to_migratetype(page_ext->gfp_mask); ret += snprintf(kbuf + ret, count - ret, - "PFN %lu Block %lu type %d %s Flags %s%s%s%s%s%s%s%s%s%s%s%s\n", + "PFN %lu type %s Block %lu type %s Flags %#lx(%pGp)\n", pfn, + migratetype_names[page_mt], pfn >> pageblock_order, - pageblock_mt, - pageblock_mt != page_mt ? "Fallback" : " ", - PageLocked(page) ? "K" : " ", - PageError(page) ? "E" : " ", - PageReferenced(page) ? "R" : " ", - PageUptodate(page) ? "U" : " ", - PageDirty(page) ? "D" : " ", - PageLRU(page) ? "L" : " ", - PageActive(page) ? "A" : " ", - PageSlab(page) ? "S" : " ", - PageWriteback(page) ? "W" : " ", - PageCompound(page) ? "C" : " ", - PageSwapCache(page) ? "B" : " ", - PageMappedToDisk(page) ? "M" : " "); + migratetype_names[pageblock_mt], + page->flags, &page->flags); if (ret >= count) goto err; @@ -135,6 +160,14 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn, if (ret >= count) goto err; + if (page_ext->last_migrate_reason != -1) { + ret += snprintf(kbuf + ret, count - ret, + "Page has been migrated, last migrate reason: %s\n", + migrate_reason_names[page_ext->last_migrate_reason]); + if (ret >= count) + goto err; + } + ret += snprintf(kbuf + ret, count - ret, "\n"); if (ret >= count) goto err; @@ -150,6 +183,30 @@ err: return -ENOMEM; } +void __dump_page_owner(struct page *page) +{ + struct page_ext *page_ext = lookup_page_ext(page); + struct stack_trace trace = { + .nr_entries = page_ext->nr_entries, + .entries = &page_ext->trace_entries[0], + }; + gfp_t gfp_mask = page_ext->gfp_mask; + int mt = gfpflags_to_migratetype(gfp_mask); + + if (!test_bit(PAGE_EXT_OWNER, &page_ext->flags)) { + pr_alert("page_owner info is not active (free page?)\n"); + return; + } + + pr_alert("page allocated via order %u, migratetype %s, gfp_mask %#x(%pGg)\n", + page_ext->order, migratetype_names[mt], gfp_mask, &gfp_mask); + print_stack_trace(&trace, 0); + + if (page_ext->last_migrate_reason != -1) + pr_alert("page has been migrated, last migrate reason: %s\n", + migrate_reason_names[page_ext->last_migrate_reason]); +} + static ssize_t read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos) { @@ -157,7 +214,7 @@ read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos) struct page *page; struct page_ext *page_ext; - if (!page_owner_inited) + if (!static_branch_unlikely(&page_owner_inited)) return -EINVAL; page = NULL; @@ -305,7 +362,7 @@ static int __init pageowner_init(void) { struct dentry *dentry; - if (!page_owner_inited) { + if (!static_branch_unlikely(&page_owner_inited)) { pr_info("page_owner is disabled\n"); return 0; }