linux-ext4 - [PATCH 3/3] ext4: Do no use yield() in ext4 code

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]

Message-Id: <1362730998-3263-3-git-send-email-lczerner@redhat.com>
Date:	Fri,  8 Mar 2013 09:23:18 +0100
From:	Lukas Czerner <lczerner@...hat.com>
To:	linux-ext4@...r.kernel.org
Cc:	Lukas Czerner <lczerner@...hat.com>
Subject: [PATCH 3/3] ext4: Do no use yield() in ext4 code

Using yield() is strongly discouraged (see sched/core.c) especially
since we can just use cond_resched().

Replace all use of yield() with cond_resched().

Signed-off-by: Lukas Czerner <lczerner@...hat.com>
---
 fs/ext4/inode.c   |    2 +-
 fs/ext4/mballoc.c |    8 ++------
 2 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 9ea0cde..ab28090 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1263,7 +1263,7 @@ repeat:
 		ei->i_da_metadata_calc_last_lblock = save_last_lblock;
 		spin_unlock(&ei->i_block_reservation_lock);
 		if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
-			yield();
+			cond_resched();
 			goto repeat;
 		}
 		dquot_release_reservation_block(inode, EXT4_C2B(sbi, 1));
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 0a493a1..d2ec0d8 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -3692,11 +3692,7 @@ repeat:
 	if (free < needed && busy) {
 		busy = 0;
 		ext4_unlock_group(sb, group);
-		/*
-		 * Yield the CPU here so that we don't get soft lockup
-		 * in non preempt case.
-		 */
-		yield();
+		cond_resched();
 		goto repeat;
 	}
 
@@ -4246,7 +4242,7 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
 			ext4_claim_free_clusters(sbi, ar->len, ar->flags)) {
 
 			/* let others to free the space */
-			yield();
+			cond_resched();
 			ar->len = ar->len >> 1;
 		}
 		if (!ar->len) {
-- 
1.7.7.6

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html