linux-kernel - [PATCH 03/12] buffer: eliminate the need to call free_more_memory() in __getblk

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 27 Sep 2017 14:13:50 -0600
From:   Jens Axboe <axboe@...nel.dk>
To:     linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org
Cc:     hannes@...xchg.org, jack@...e.cz, torvalds@...ux-foundation.org,
        Jens Axboe <axboe@...nel.dk>
Subject: [PATCH 03/12] buffer: eliminate the need to call free_more_memory() in __getblk_slow()

Since the previous commit removed any case where grow_buffers()
would return failure due to memory allocations, we can safely
remove the case where we have to call free_more_memory() in
this function.

Since this is also the last user of free_more_memory(), kill
it off completely.

Signed-off-by: Jens Axboe <axboe@...nel.dk>
---
 fs/buffer.c | 23 -----------------------
 1 file changed, 23 deletions(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index 3b60cd8456db..bff571dc7bc3 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -253,27 +253,6 @@ __find_get_block_slow(struct block_device *bdev, sector_t block)
 }
 
 /*
- * Kick the writeback threads then try to free up some ZONE_NORMAL memory.
- */
-static void free_more_memory(void)
-{
-	struct zoneref *z;
-	int nid;
-
-	wakeup_flusher_threads(1024, WB_REASON_FREE_MORE_MEM);
-	yield();
-
-	for_each_online_node(nid) {
-
-		z = first_zones_zonelist(node_zonelist(nid, GFP_NOFS),
-						gfp_zone(GFP_NOFS), NULL);
-		if (z->zone)
-			try_to_free_pages(node_zonelist(nid, GFP_NOFS), 0,
-						GFP_NOFS, NULL);
-	}
-}
-
-/*
  * I/O completion handler for block_read_full_page() - pages
  * which come unlocked at the end of I/O.
  */
@@ -1086,8 +1065,6 @@ __getblk_slow(struct block_device *bdev, sector_t block,
 		ret = grow_buffers(bdev, block, size, gfp);
 		if (ret < 0)
 			return NULL;
-		if (ret == 0)
-			free_more_memory();
 	}
 }
 
-- 
2.7.4