diff options
Diffstat (limited to 'include/linux/pgalloc_tag.h')
| -rw-r--r-- | include/linux/pgalloc_tag.h | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/include/linux/pgalloc_tag.h b/include/linux/pgalloc_tag.h new file mode 100644 index 000000000000..8a7f4f802c57 --- /dev/null +++ b/include/linux/pgalloc_tag.h @@ -0,0 +1,213 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * page allocation tagging + */ +#ifndef _LINUX_PGALLOC_TAG_H +#define _LINUX_PGALLOC_TAG_H + +#include <linux/alloc_tag.h> + +#ifdef CONFIG_MEM_ALLOC_PROFILING + +#include <linux/page_ext.h> + +extern struct page_ext_operations page_alloc_tagging_ops; +extern unsigned long alloc_tag_ref_mask; +extern int alloc_tag_ref_offs; +extern struct alloc_tag_kernel_section kernel_tags; + +DECLARE_STATIC_KEY_FALSE(mem_profiling_compressed); + +typedef u16 pgalloc_tag_idx; + +union pgtag_ref_handle { + union codetag_ref *ref; /* reference in page extension */ + struct page *page; /* reference in page flags */ +}; + +/* Reserved indexes */ +#define CODETAG_ID_NULL 0 +#define CODETAG_ID_EMPTY 1 +#define CODETAG_ID_FIRST 2 + +#ifdef CONFIG_MODULES + +extern struct alloc_tag_module_section module_tags; + +static inline struct alloc_tag *module_idx_to_tag(pgalloc_tag_idx idx) +{ + return &module_tags.first_tag[idx - kernel_tags.count]; +} + +static inline pgalloc_tag_idx module_tag_to_idx(struct alloc_tag *tag) +{ + return CODETAG_ID_FIRST + kernel_tags.count + (tag - module_tags.first_tag); +} + +#else /* CONFIG_MODULES */ + +static inline struct alloc_tag *module_idx_to_tag(pgalloc_tag_idx idx) +{ + pr_warn("invalid page tag reference %lu\n", (unsigned long)idx); + return NULL; +} + +static inline pgalloc_tag_idx module_tag_to_idx(struct alloc_tag *tag) +{ + pr_warn("invalid page tag 0x%lx\n", (unsigned long)tag); + return CODETAG_ID_NULL; +} + +#endif /* CONFIG_MODULES */ + +static inline void idx_to_ref(pgalloc_tag_idx idx, union codetag_ref *ref) +{ + switch (idx) { + case (CODETAG_ID_NULL): + ref->ct = NULL; + break; + case (CODETAG_ID_EMPTY): + set_codetag_empty(ref); + break; + default: + idx -= CODETAG_ID_FIRST; + ref->ct = idx < kernel_tags.count ? + &kernel_tags.first_tag[idx].ct : + &module_idx_to_tag(idx)->ct; + break; + } +} + +static inline pgalloc_tag_idx ref_to_idx(union codetag_ref *ref) +{ + struct alloc_tag *tag; + + if (!ref->ct) + return CODETAG_ID_NULL; + + if (is_codetag_empty(ref)) + return CODETAG_ID_EMPTY; + + tag = ct_to_alloc_tag(ref->ct); + if (tag >= kernel_tags.first_tag && tag < kernel_tags.first_tag + kernel_tags.count) + return CODETAG_ID_FIRST + (tag - kernel_tags.first_tag); + + return module_tag_to_idx(tag); +} + + + +/* Should be called only if mem_alloc_profiling_enabled() */ +static inline bool get_page_tag_ref(struct page *page, union codetag_ref *ref, + union pgtag_ref_handle *handle) +{ + if (!page) + return false; + + if (static_key_enabled(&mem_profiling_compressed)) { + pgalloc_tag_idx idx; + + idx = (page->flags >> alloc_tag_ref_offs) & alloc_tag_ref_mask; + idx_to_ref(idx, ref); + handle->page = page; + } else { + struct page_ext *page_ext; + union codetag_ref *tmp; + + page_ext = page_ext_get(page); + if (!page_ext) + return false; + + tmp = (union codetag_ref *)page_ext_data(page_ext, &page_alloc_tagging_ops); + ref->ct = tmp->ct; + handle->ref = tmp; + } + + return true; +} + +static inline void put_page_tag_ref(union pgtag_ref_handle handle) +{ + if (WARN_ON(!handle.ref)) + return; + + if (!static_key_enabled(&mem_profiling_compressed)) + page_ext_put((void *)handle.ref - page_alloc_tagging_ops.offset); +} + +static inline void update_page_tag_ref(union pgtag_ref_handle handle, union codetag_ref *ref) +{ + if (static_key_enabled(&mem_profiling_compressed)) { + struct page *page = handle.page; + unsigned long old_flags; + unsigned long flags; + unsigned long idx; + + if (WARN_ON(!page || !ref)) + return; + + idx = (unsigned long)ref_to_idx(ref); + idx = (idx & alloc_tag_ref_mask) << alloc_tag_ref_offs; + do { + old_flags = READ_ONCE(page->flags); + flags = old_flags; + flags &= ~(alloc_tag_ref_mask << alloc_tag_ref_offs); + flags |= idx; + } while (unlikely(!try_cmpxchg(&page->flags, &old_flags, flags))); + } else { + if (WARN_ON(!handle.ref || !ref)) + return; + + handle.ref->ct = ref->ct; + } +} + +/* Should be called only if mem_alloc_profiling_enabled() */ +void __clear_page_tag_ref(struct page *page); + +static inline void clear_page_tag_ref(struct page *page) +{ + if (mem_alloc_profiling_enabled()) + __clear_page_tag_ref(page); +} + +/* Should be called only if mem_alloc_profiling_enabled() */ +static inline struct alloc_tag *__pgalloc_tag_get(struct page *page) +{ + struct alloc_tag *tag = NULL; + union pgtag_ref_handle handle; + union codetag_ref ref; + + if (get_page_tag_ref(page, &ref, &handle)) { + alloc_tag_sub_check(&ref); + if (ref.ct) + tag = ct_to_alloc_tag(ref.ct); + put_page_tag_ref(handle); + } + + return tag; +} + +static inline struct alloc_tag *pgalloc_tag_get(struct page *page) +{ + if (mem_alloc_profiling_enabled()) + return __pgalloc_tag_get(page); + return NULL; +} + +void pgalloc_tag_split(struct folio *folio, int old_order, int new_order); +void pgalloc_tag_swap(struct folio *new, struct folio *old); + +void __init alloc_tag_sec_init(void); + +#else /* CONFIG_MEM_ALLOC_PROFILING */ + +static inline void clear_page_tag_ref(struct page *page) {} +static inline void alloc_tag_sec_init(void) {} +static inline void pgalloc_tag_split(struct folio *folio, int old_order, int new_order) {} +static inline void pgalloc_tag_swap(struct folio *new, struct folio *old) {} +static inline struct alloc_tag *pgalloc_tag_get(struct page *page) { return NULL; } + +#endif /* CONFIG_MEM_ALLOC_PROFILING */ + +#endif /* _LINUX_PGALLOC_TAG_H */ |