netdev - [PATCH net-next 1/7] tipc: replace reference table rwlock with spinlock

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, 12 Mar 2014 11:31:07 -0400
From:	Jon Maloy <jon.maloy@...csson.com>
To:	davem@...emloft.net
Cc:	netdev@...r.kernel.org,
	Paul Gortmaker <paul.gortmaker@...driver.com>,
	erik.hugne@...csson.com, ying.xue@...driver.com, maloy@...jonn.com,
	tipc-discussion@...ts.sourceforge.net,
	Jon Maloy <jon.maloy@...csson.com>
Subject: [PATCH net-next 1/7] tipc: replace reference table rwlock with spinlock

The lock for protecting the reference table is declared as an
RWLOCK, although it is only used in write mode, never in read
mode.

We redefine it to become a spinlock.

Signed-off-by: Jon Maloy <jon.maloy@...csson.com>
Reviewed-by: Ying Xue <ying.xue@...driver.com>
Reviewed-by: Erik Hugne <erik.hugne@...csson.com>
---
 net/tipc/ref.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/tipc/ref.c b/net/tipc/ref.c
index de3d593..67176b5 100644
--- a/net/tipc/ref.c
+++ b/net/tipc/ref.c
@@ -89,7 +89,7 @@ struct ref_table {
 
 static struct ref_table tipc_ref_table;
 
-static DEFINE_RWLOCK(ref_table_lock);
+static DEFINE_SPINLOCK(ref_table_lock);
 
 /**
  * tipc_ref_table_init - create reference table for objects
@@ -159,7 +159,7 @@ u32 tipc_ref_acquire(void *object, spinlock_t **lock)
 	}
 
 	/* take a free entry, if available; otherwise initialize a new entry */
-	write_lock_bh(&ref_table_lock);
+	spin_lock_bh(&ref_table_lock);
 	if (tipc_ref_table.first_free) {
 		index = tipc_ref_table.first_free;
 		entry = &(tipc_ref_table.entries[index]);
@@ -175,7 +175,7 @@ u32 tipc_ref_acquire(void *object, spinlock_t **lock)
 	} else {
 		ref = 0;
 	}
-	write_unlock_bh(&ref_table_lock);
+	spin_unlock_bh(&ref_table_lock);
 
 	/*
 	 * Grab the lock so no one else can modify this entry
@@ -216,7 +216,7 @@ void tipc_ref_discard(u32 ref)
 	index = ref & index_mask;
 	entry = &(tipc_ref_table.entries[index]);
 
-	write_lock_bh(&ref_table_lock);
+	spin_lock_bh(&ref_table_lock);
 
 	if (!entry->object) {
 		pr_err("Attempt to discard ref. to non-existent obj\n");
@@ -242,7 +242,7 @@ void tipc_ref_discard(u32 ref)
 	tipc_ref_table.last_free = index;
 
 exit:
-	write_unlock_bh(&ref_table_lock);
+	spin_unlock_bh(&ref_table_lock);
 }
 
 /**
-- 
1.7.9.5

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