Re: [RFC PATCH 10/30] mm: enable page allocation tagging for __get_free_pages and alloc_pages
From: Mel Gorman <mgorman@suse.de>
Date: 2022-08-31 10:11:34
Also in:
io-uring, linux-arch, linux-bcache, linux-iommu, linux-mm, lkml, xen-devel
On Tue, Aug 30, 2022 at 02:48:59PM -0700, Suren Baghdasaryan wrote:
quoted hunk ↗ jump to hunk
Redefine alloc_pages, __get_free_pages to record allocations done by these functions. Instrument deallocation hooks to record object freeing. Signed-off-by: Suren Baghdasaryan <surenb@google.com> +#ifdef CONFIG_PAGE_ALLOC_TAGGING + #include <linux/alloc_tag.h> #include <linux/page_ext.h>@@ -25,4 +27,37 @@ static inline void pgalloc_tag_dec(struct page *page, unsigned int order) alloc_tag_sub(get_page_tag_ref(page), PAGE_SIZE << order); } +/* + * Redefinitions of the common page allocators/destructors + */ +#define pgtag_alloc_pages(gfp, order) \ +({ \ + struct page *_page = _alloc_pages((gfp), (order)); \ + \ + if (_page) \ + alloc_tag_add(get_page_tag_ref(_page), PAGE_SIZE << (order));\ + _page; \ +}) +
Instead of renaming alloc_pages, why is the tagging not done in __alloc_pages()? At least __alloc_pages_bulk() is also missed. The branch can be guarded with IS_ENABLED.
+#define pgtag_get_free_pages(gfp_mask, order) \
+({ \
+ struct page *_page; \
+ unsigned long _res = _get_free_pages((gfp_mask), (order), &_page);\
+ \
+ if (_res) \
+ alloc_tag_add(get_page_tag_ref(_page), PAGE_SIZE << (order));\
+ _res; \
+})
+Similar, the tagging could happen in a core function instead of a wrapper.
quoted hunk ↗ jump to hunk
+#else /* CONFIG_PAGE_ALLOC_TAGGING */ + +#define pgtag_alloc_pages(gfp, order) _alloc_pages(gfp, order) + +#define pgtag_get_free_pages(gfp_mask, order) \ + _get_free_pages((gfp_mask), (order), NULL) + +#define pgalloc_tag_dec(__page, __size) do {} while (0) + +#endif /* CONFIG_PAGE_ALLOC_TAGGING */ + #endif /* _LINUX_PGALLOC_TAG_H */diff --git a/mm/mempolicy.c b/mm/mempolicy.c index b73d3248d976..f7e6d9564a49 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c@@ -2249,7 +2249,7 @@ EXPORT_SYMBOL(vma_alloc_folio); * flags are used. * Return: The page on success or NULL if allocation fails. */ -struct page *alloc_pages(gfp_t gfp, unsigned order) +struct page *_alloc_pages(gfp_t gfp, unsigned int order) { struct mempolicy *pol = &default_policy; struct page *page;@@ -2273,7 +2273,7 @@ struct page *alloc_pages(gfp_t gfp, unsigned order) return page; } -EXPORT_SYMBOL(alloc_pages); +EXPORT_SYMBOL(_alloc_pages); struct folio *folio_alloc(gfp_t gfp, unsigned order) {diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e5486d47406e..165daba19e2a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c@@ -763,6 +763,7 @@ static inline bool pcp_allowed_order(unsigned int order) static inline void free_the_page(struct page *page, unsigned int order) { + if (pcp_allowed_order(order)) /* Via pcp? */ free_unref_page(page, order); else
Spurious wide-space change. -- Mel Gorman SUSE Labs