path: root/include/linux
diff options
authorSong Liu <songliubraving@fb.com>2019-09-23 15:38:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-24 15:54:11 -0700
commit010c164a5fa7e169deab0a4d8211611f1930c1cd (patch)
treefb07bdd2cf844ccf1e1aaf6fc40e42399fb0dc19 /include/linux
parent87eaceb3faa59b9b4d940ec9554ce251325d83fe (diff)
mm: move memcmp_pages() and pages_identical()
Patch series "THP aware uprobe", v13. This patchset makes uprobe aware of THPs. Currently, when uprobe is attached to text on THP, the page is split by FOLL_SPLIT. As a result, uprobe eliminates the performance benefit of THP. This set makes uprobe THP-aware. Instead of FOLL_SPLIT, we introduces FOLL_SPLIT_PMD, which only split PMD for uprobe. After all uprobes within the THP are removed, the PTE-mapped pages are regrouped as huge PMD. This set (plus a few THP patches) is also available at https://github.com/liu-song-6/linux/tree/uprobe-thp This patch (of 6): Move memcmp_pages() to mm/util.c and pages_identical() to mm.h, so that we can use them in other files. Link: http://lkml.kernel.org/r/20190815164525.1848545-2-songliubraving@fb.com Signed-off-by: Song Liu <songliubraving@fb.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox <matthew.wilcox@oracle.com> Cc: William Kucharski <william.kucharski@oracle.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux')
1 files changed, 7 insertions, 0 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 57a9fa34f159..0ac87d9ee9d8 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2868,5 +2868,12 @@ void __init setup_nr_node_ids(void);
static inline void setup_nr_node_ids(void) {}
+extern int memcmp_pages(struct page *page1, struct page *page2);
+static inline int pages_identical(struct page *page1, struct page *page2)
+ return !memcmp_pages(page1, page2);
#endif /* __KERNEL__ */
#endif /* _LINUX_MM_H */

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