diff mbox series

[057/181] proc: optimise smaps for shmem entries

Message ID 20201013235128._17ynTigl%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [001/181] compiler-clang: add build check for clang 10.0.1 | expand

Commit Message

Andrew Morton Oct. 13, 2020, 11:51 p.m. UTC 
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: proc: optimise smaps for shmem entries

Avoid bumping the refcount on pages when we're only interested in the
swap entries.

Link: https://lkml.kernel.org/r/20200910183318.20139-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/proc/task_mmu.c |    8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)
diff mbox series

Patch

--- a/fs/proc/task_mmu.c~proc-optimise-smaps-for-shmem-entries
+++ a/fs/proc/task_mmu.c
@@ -520,16 +520,10 @@  static void smaps_pte_entry(pte_t *pte,
 			page = device_private_entry_to_page(swpent);
 	} else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
 							&& pte_none(*pte))) {
-		page = find_get_entry(vma->vm_file->f_mapping,
+		page = xa_load(&vma->vm_file->f_mapping->i_pages,
 						linear_page_index(vma, addr));
-		if (!page)
-			return;
-
 		if (xa_is_value(page))
 			mss->swap += PAGE_SIZE;
-		else
-			put_page(page);
-
 		return;
 	}