[merged] mm-document-why-we-dont-set-pagereadahead.patch removed from -mm tree

[merged] mm-document-why-we-dont-set-pagereadahead.patch removed from -mm tree

[akpm]

The patch titled
     Subject: mm: document why we don't set PageReadahead
has been removed from the -mm tree.  Its filename was
     mm-document-why-we-dont-set-pagereadahead.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm: document why we don't set PageReadahead

If the page is already in cache, we don't set PageReadahead on it.

Link: http://lkml.kernel.org/r/20200414150233.24495-15-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Gao Xiang <gaoxiang25@huawei.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/readahead.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/mm/readahead.c~mm-document-why-we-dont-set-pagereadahead
+++ a/mm/readahead.c
@@ -195,9 +195,12 @@ void page_cache_readahead_unbounded(stru
 
 		if (page && !xa_is_value(page)) {
 			/*
-			 * Page already present?  Kick off the current batch of
-			 * contiguous pages before continuing with the next
-			 * batch.
+			 * Page already present?  Kick off the current batch
+			 * of contiguous pages before continuing with the
+			 * next batch.  This page may be the one we would
+			 * have intended to mark as Readahead, but we don't
+			 * have a stable reference to this page, and it's
+			 * not worth getting one just for that.
 			 */
 			read_pages(&rac, &page_pool, true);
 			continue;
_

Patches currently in -mm which might be from willy@infradead.org are

mm-simplify-calling-a-compound-page-destructor.patch
ipc-convert-ipcs_idr-to-xarray.patch
ipc-convert-ipcs_idr-to-xarray-update.patch