From dcfe378c81f72f146890ce1dcfdcc742d3b66924 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Thu, 21 Mar 2024 09:36:36 -0700 Subject: lib: introduce support for page allocation tagging MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Introduce helper functions to easily instrument page allocators by storing a pointer to the allocation tag associated with the code that allocated the page in a page_ext field. Link: https://lkml.kernel.org/r/20240321163705.3067592-15-surenb@google.com Signed-off-by: Suren Baghdasaryan Co-developed-by: Kent Overstreet Signed-off-by: Kent Overstreet Reviewed-by: Vlastimil Babka Tested-by: Kees Cook Cc: Alexander Viro Cc: Alex Gaynor Cc: Alice Ryhl Cc: Andreas Hindborg Cc: Benno Lossin Cc: "Björn Roy Baron" Cc: Boqun Feng Cc: Christoph Lameter Cc: Dennis Zhou Cc: Gary Guo Cc: Miguel Ojeda Cc: Pasha Tatashin Cc: Peter Zijlstra Cc: Tejun Heo Cc: Wedson Almeida Filho Signed-off-by: Andrew Morton --- include/linux/pgalloc_tag.h | 78 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) create mode 100644 include/linux/pgalloc_tag.h (limited to 'include/linux/pgalloc_tag.h') diff --git a/include/linux/pgalloc_tag.h b/include/linux/pgalloc_tag.h new file mode 100644 index 000000000000..66bd021eb46e --- /dev/null +++ b/include/linux/pgalloc_tag.h @@ -0,0 +1,78 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * page allocation tagging + */ +#ifndef _LINUX_PGALLOC_TAG_H +#define _LINUX_PGALLOC_TAG_H + +#include + +#ifdef CONFIG_MEM_ALLOC_PROFILING + +#include + +extern struct page_ext_operations page_alloc_tagging_ops; +extern struct page_ext *page_ext_get(struct page *page); +extern void page_ext_put(struct page_ext *page_ext); + +static inline union codetag_ref *codetag_ref_from_page_ext(struct page_ext *page_ext) +{ + return (void *)page_ext + page_alloc_tagging_ops.offset; +} + +static inline struct page_ext *page_ext_from_codetag_ref(union codetag_ref *ref) +{ + return (void *)ref - page_alloc_tagging_ops.offset; +} + +/* Should be called only if mem_alloc_profiling_enabled() */ +static inline union codetag_ref *get_page_tag_ref(struct page *page) +{ + if (page) { + struct page_ext *page_ext = page_ext_get(page); + + if (page_ext) + return codetag_ref_from_page_ext(page_ext); + } + return NULL; +} + +static inline void put_page_tag_ref(union codetag_ref *ref) +{ + page_ext_put(page_ext_from_codetag_ref(ref)); +} + +static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, + unsigned int nr) +{ + if (mem_alloc_profiling_enabled()) { + union codetag_ref *ref = get_page_tag_ref(page); + + if (ref) { + alloc_tag_add(ref, task->alloc_tag, PAGE_SIZE * nr); + put_page_tag_ref(ref); + } + } +} + +static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) +{ + if (mem_alloc_profiling_enabled()) { + union codetag_ref *ref = get_page_tag_ref(page); + + if (ref) { + alloc_tag_sub(ref, PAGE_SIZE * nr); + put_page_tag_ref(ref); + } + } +} + +#else /* CONFIG_MEM_ALLOC_PROFILING */ + +static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, + unsigned int nr) {} +static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) {} + +#endif /* CONFIG_MEM_ALLOC_PROFILING */ + +#endif /* _LINUX_PGALLOC_TAG_H */ -- cgit v1.3 From be25d1d4e822a703b19043baff916aec6ac4362d Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Thu, 21 Mar 2024 09:36:41 -0700 Subject: mm: create new codetag references during page splitting MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When a high-order page is split into smaller ones, each newly split page should get its codetag. After the split each split page will be referencing the original codetag. The codetag's "bytes" counter remains the same because the amount of allocated memory has not changed, however the "calls" counter gets increased to keep the counter correct when these individual pages get freed. Link: https://lkml.kernel.org/r/20240321163705.3067592-20-surenb@google.com Signed-off-by: Suren Baghdasaryan Reviewed-by: Vlastimil Babka Tested-by: Kees Cook Cc: Alexander Viro Cc: Alex Gaynor Cc: Alice Ryhl Cc: Andreas Hindborg Cc: Benno Lossin Cc: "Björn Roy Baron" Cc: Boqun Feng Cc: Christoph Lameter Cc: Dennis Zhou Cc: Gary Guo Cc: Kent Overstreet Cc: Miguel Ojeda Cc: Pasha Tatashin Cc: Peter Zijlstra Cc: Tejun Heo Cc: Wedson Almeida Filho Signed-off-by: Andrew Morton --- include/linux/alloc_tag.h | 9 +++++++++ include/linux/pgalloc_tag.h | 30 ++++++++++++++++++++++++++++++ mm/huge_memory.c | 2 ++ mm/page_alloc.c | 2 ++ 4 files changed, 43 insertions(+) (limited to 'include/linux/pgalloc_tag.h') diff --git a/include/linux/alloc_tag.h b/include/linux/alloc_tag.h index 8932187124da..2aea7afa1fab 100644 --- a/include/linux/alloc_tag.h +++ b/include/linux/alloc_tag.h @@ -117,6 +117,15 @@ static inline void __alloc_tag_ref_set(union codetag_ref *ref, struct alloc_tag this_cpu_inc(tag->counters->calls); } +static inline void alloc_tag_ref_set(union codetag_ref *ref, struct alloc_tag *tag) +{ + alloc_tag_add_check(ref, tag); + if (!ref || !tag) + return; + + __alloc_tag_ref_set(ref, tag); +} + static inline void alloc_tag_add(union codetag_ref *ref, struct alloc_tag *tag, size_t bytes) { alloc_tag_add_check(ref, tag); diff --git a/include/linux/pgalloc_tag.h b/include/linux/pgalloc_tag.h index 66bd021eb46e..093edf98c3d7 100644 --- a/include/linux/pgalloc_tag.h +++ b/include/linux/pgalloc_tag.h @@ -67,11 +67,41 @@ static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) } } +static inline void pgalloc_tag_split(struct page *page, unsigned int nr) +{ + int i; + struct page_ext *page_ext; + union codetag_ref *ref; + struct alloc_tag *tag; + + if (!mem_alloc_profiling_enabled()) + return; + + page_ext = page_ext_get(page); + if (unlikely(!page_ext)) + return; + + ref = codetag_ref_from_page_ext(page_ext); + if (!ref->ct) + goto out; + + tag = ct_to_alloc_tag(ref->ct); + page_ext = page_ext_next(page_ext); + for (i = 1; i < nr; i++) { + /* Set new reference to point to the original tag */ + alloc_tag_ref_set(codetag_ref_from_page_ext(page_ext), tag); + page_ext = page_ext_next(page_ext); + } +out: + page_ext_put(page_ext); +} + #else /* CONFIG_MEM_ALLOC_PROFILING */ static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, unsigned int nr) {} static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) {} +static inline void pgalloc_tag_split(struct page *page, unsigned int nr) {} #endif /* CONFIG_MEM_ALLOC_PROFILING */ diff --git a/mm/huge_memory.c b/mm/huge_memory.c index dd88bb3ea196..25191ab70631 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -38,6 +38,7 @@ #include #include #include +#include #include #include @@ -2946,6 +2947,7 @@ static void __split_huge_page(struct page *page, struct list_head *list, /* Caller disabled irqs, so they are still disabled here */ split_page_owner(head, order, new_order); + pgalloc_tag_split(head, 1 << order); /* See comment in __split_huge_page_tail() */ if (folio_test_anon(folio)) { diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d3afaf8f983a..e453ee22d489 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2630,6 +2630,7 @@ void split_page(struct page *page, unsigned int order) for (i = 1; i < (1 << order); i++) set_page_refcounted(page + i); split_page_owner(page, order, 0); + pgalloc_tag_split(page, 1 << order); split_page_memcg(page, order, 0); } EXPORT_SYMBOL_GPL(split_page); @@ -4827,6 +4828,7 @@ static void *make_alloc_exact(unsigned long addr, unsigned int order, struct page *last = page + nr; split_page_owner(page, order, 0); + pgalloc_tag_split(page, 1 << order); split_page_memcg(page, order, 0); while (page < --last) set_page_refcounted(last); -- cgit v1.3 From cc92eba1c88b1f74e0f044df2738f4e4b22f1e4e Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Thu, 21 Mar 2024 09:36:42 -0700 Subject: mm: fix non-compound multi-order memory accounting in __free_pages MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When a non-compound multi-order page is freed, it is possible that a speculative reference keeps the page pinned. In this case we free all pages except for the first page, which will be freed later by the last put_page(). However the page passed to put_page() is indistinguishable from an order-0 page, so it cannot do the accounting, just as it cannot free the subsequent pages. Do the accounting here, where we free the pages. Link: https://lkml.kernel.org/r/20240321163705.3067592-21-surenb@google.com Reported-by: Vlastimil Babka Signed-off-by: Suren Baghdasaryan Tested-by: Kees Cook Cc: Alexander Viro Cc: Alex Gaynor Cc: Alice Ryhl Cc: Andreas Hindborg Cc: Benno Lossin Cc: "Björn Roy Baron" Cc: Boqun Feng Cc: Christoph Lameter Cc: Dennis Zhou Cc: Gary Guo Cc: Kent Overstreet Cc: Miguel Ojeda Cc: Pasha Tatashin Cc: Peter Zijlstra Cc: Tejun Heo Cc: Wedson Almeida Filho Signed-off-by: Andrew Morton --- include/linux/pgalloc_tag.h | 24 ++++++++++++++++++++++++ mm/page_alloc.c | 5 ++++- 2 files changed, 28 insertions(+), 1 deletion(-) (limited to 'include/linux/pgalloc_tag.h') diff --git a/include/linux/pgalloc_tag.h b/include/linux/pgalloc_tag.h index 093edf98c3d7..50d212330bbb 100644 --- a/include/linux/pgalloc_tag.h +++ b/include/linux/pgalloc_tag.h @@ -96,12 +96,36 @@ out: page_ext_put(page_ext); } +static inline struct alloc_tag *pgalloc_tag_get(struct page *page) +{ + struct alloc_tag *tag = NULL; + + if (mem_alloc_profiling_enabled()) { + union codetag_ref *ref = get_page_tag_ref(page); + + alloc_tag_sub_check(ref); + if (ref && ref->ct) + tag = ct_to_alloc_tag(ref->ct); + put_page_tag_ref(ref); + } + + return tag; +} + +static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr) +{ + if (mem_alloc_profiling_enabled() && tag) + this_cpu_sub(tag->counters->bytes, PAGE_SIZE * nr); +} + #else /* CONFIG_MEM_ALLOC_PROFILING */ static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, unsigned int nr) {} static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) {} static inline void pgalloc_tag_split(struct page *page, unsigned int nr) {} +static inline struct alloc_tag *pgalloc_tag_get(struct page *page) { return NULL; } +static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr) {} #endif /* CONFIG_MEM_ALLOC_PROFILING */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e453ee22d489..e1241ecef271 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4664,12 +4664,15 @@ void __free_pages(struct page *page, unsigned int order) { /* get PageHead before we drop reference */ int head = PageHead(page); + struct alloc_tag *tag = pgalloc_tag_get(page); if (put_page_testzero(page)) free_the_page(page, order); - else if (!head) + else if (!head) { + pgalloc_tag_sub_pages(tag, (1 << order) - 1); while (order-- > 0) free_the_page(page + (1 << order), order); + } } EXPORT_SYMBOL(__free_pages); -- cgit v1.3 From d224eb0287fbd84f4f13eca042c7f08f87138f3b Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Thu, 21 Mar 2024 09:36:56 -0700 Subject: codetag: debug: mark codetags for reserved pages as empty MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit To avoid debug warnings while freeing reserved pages which were not allocated with usual allocators, mark their codetags as empty before freeing. Link: https://lkml.kernel.org/r/20240321163705.3067592-35-surenb@google.com Signed-off-by: Suren Baghdasaryan Reviewed-by: Kees Cook Tested-by: Kees Cook Cc: Alexander Viro Cc: Alex Gaynor Cc: Alice Ryhl Cc: Andreas Hindborg Cc: Benno Lossin Cc: "Björn Roy Baron" Cc: Boqun Feng Cc: Christoph Lameter Cc: Dennis Zhou Cc: Gary Guo Cc: Kent Overstreet Cc: Miguel Ojeda Cc: Pasha Tatashin Cc: Peter Zijlstra Cc: Tejun Heo Cc: Vlastimil Babka Cc: Wedson Almeida Filho Signed-off-by: Andrew Morton --- include/linux/alloc_tag.h | 1 + include/linux/mm.h | 9 +++++++++ include/linux/pgalloc_tag.h | 2 ++ mm/mm_init.c | 12 +++++++++++- 4 files changed, 23 insertions(+), 1 deletion(-) (limited to 'include/linux/pgalloc_tag.h') diff --git a/include/linux/alloc_tag.h b/include/linux/alloc_tag.h index 3af5d6a5ced4..afc9e259a2d3 100644 --- a/include/linux/alloc_tag.h +++ b/include/linux/alloc_tag.h @@ -47,6 +47,7 @@ static inline void set_codetag_empty(union codetag_ref *ref) #else /* CONFIG_MEM_ALLOC_PROFILING_DEBUG */ static inline bool is_codetag_empty(union codetag_ref *ref) { return false; } +static inline void set_codetag_empty(union codetag_ref *ref) {} #endif /* CONFIG_MEM_ALLOC_PROFILING_DEBUG */ diff --git a/include/linux/mm.h b/include/linux/mm.h index b6bdaa18b9e9..0dbd737cfabd 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -5,6 +5,7 @@ #include #include #include +#include #include #include #include @@ -3134,6 +3135,14 @@ extern void reserve_bootmem_region(phys_addr_t start, /* Free the reserved page into the buddy system, so it gets managed. */ static inline void free_reserved_page(struct page *page) { + if (mem_alloc_profiling_enabled()) { + union codetag_ref *ref = get_page_tag_ref(page); + + if (ref) { + set_codetag_empty(ref); + put_page_tag_ref(ref); + } + } ClearPageReserved(page); init_page_count(page); __free_page(page); diff --git a/include/linux/pgalloc_tag.h b/include/linux/pgalloc_tag.h index 50d212330bbb..62d8dad74b37 100644 --- a/include/linux/pgalloc_tag.h +++ b/include/linux/pgalloc_tag.h @@ -120,6 +120,8 @@ static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr) #else /* CONFIG_MEM_ALLOC_PROFILING */ +static inline union codetag_ref *get_page_tag_ref(struct page *page) { return NULL; } +static inline void put_page_tag_ref(union codetag_ref *ref) {} static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, unsigned int nr) {} static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) {} diff --git a/mm/mm_init.c b/mm/mm_init.c index 2fd9bf044a79..f45c2b32ba82 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -2567,7 +2567,6 @@ void __init set_dma_reserve(unsigned long new_dma_reserve) void __init memblock_free_pages(struct page *page, unsigned long pfn, unsigned int order) { - if (IS_ENABLED(CONFIG_DEFERRED_STRUCT_PAGE_INIT)) { int nid = early_pfn_to_nid(pfn); @@ -2579,6 +2578,17 @@ void __init memblock_free_pages(struct page *page, unsigned long pfn, /* KMSAN will take care of these pages. */ return; } + + /* pages were reserved and not allocated */ + if (mem_alloc_profiling_enabled()) { + union codetag_ref *ref = get_page_tag_ref(page); + + if (ref) { + set_codetag_empty(ref); + put_page_tag_ref(ref); + } + } + __free_pages_core(page, order); } -- cgit v1.3 From 6e65aa55cdf4c7cc0490b156b4aae2035c157140 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Tue, 26 Mar 2024 17:10:25 +0000 Subject: mm: make page_ext_get() take a const argument In order to constify other functions, we need page_ext_get() to be const. This is no problem as lookup_page_ext() already takes a const argument. Link: https://lkml.kernel.org/r/20240326171045.410737-4-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- include/linux/page_ext.h | 4 ++-- include/linux/pgalloc_tag.h | 2 -- mm/page_ext.c | 2 +- 3 files changed, 3 insertions(+), 5 deletions(-) (limited to 'include/linux/pgalloc_tag.h') diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h index 07e0656898f9..e4b48a0dda24 100644 --- a/include/linux/page_ext.h +++ b/include/linux/page_ext.h @@ -77,7 +77,7 @@ static inline void page_ext_init(void) } #endif -extern struct page_ext *page_ext_get(struct page *page); +extern struct page_ext *page_ext_get(const struct page *page); extern void page_ext_put(struct page_ext *page_ext); static inline void *page_ext_data(struct page_ext *page_ext, @@ -117,7 +117,7 @@ static inline void page_ext_init_flatmem(void) { } -static inline struct page_ext *page_ext_get(struct page *page) +static inline struct page_ext *page_ext_get(const struct page *page) { return NULL; } diff --git a/include/linux/pgalloc_tag.h b/include/linux/pgalloc_tag.h index 62d8dad74b37..86ba5d33e43b 100644 --- a/include/linux/pgalloc_tag.h +++ b/include/linux/pgalloc_tag.h @@ -12,8 +12,6 @@ #include extern struct page_ext_operations page_alloc_tagging_ops; -extern struct page_ext *page_ext_get(struct page *page); -extern void page_ext_put(struct page_ext *page_ext); static inline union codetag_ref *codetag_ref_from_page_ext(struct page_ext *page_ext) { diff --git a/mm/page_ext.c b/mm/page_ext.c index e7d8f1a5589e..95dd8ffeaf81 100644 --- a/mm/page_ext.c +++ b/mm/page_ext.c @@ -514,7 +514,7 @@ void __meminit pgdat_page_ext_init(struct pglist_data *pgdat) * Context: Any context. Caller may not sleep until they have called * page_ext_put(). */ -struct page_ext *page_ext_get(struct page *page) +struct page_ext *page_ext_get(const struct page *page) { struct page_ext *page_ext; -- cgit v1.3