From: Rik van Riel <riel@surriel.com> mainline inclusion from mainline-v6.7 commit efa7df3e3bb5da8e6abbe37727417f32a37fba47 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I9H84X CVE: NA ------------------------------------------------- Align larger anonymous memory mappings on THP boundaries by going through thp_get_unmapped_area if THPs are enabled for the current process. With this patch, larger anonymous mappings are now THP aligned. When a malloc library allocates a 2MB or larger arena, that arena can now be mapped with THPs right from the start, which can result in better TLB hit rates and execution time. Link: https://lkml.kernel.org/r/20220809142457.4751229f@imladris.surriel.com Link: https://lkml.kernel.org/r/20231214223423.1133074-1-yang@os.amperecomputing.c... Signed-off-by: Rik van Riel <riel@surriel.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Christopher Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> (cherry picked from commit efa7df3e3bb5da8e6abbe37727417f32a37fba47) Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> --- mm/mmap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index 8b5295653475..6cd1ccb79193 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1850,6 +1850,9 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, */ pgoff = 0; get_area = shmem_get_unmapped_area; + } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { + /* Ensures that larger anonymous mappings are THP aligned. */ + get_area = thp_get_unmapped_area; } addr = get_area(file, addr, len, pgoff, flags); -- 2.27.0