IPv6: convert mc_lock to spinlock

Only used for writing, so convert to spinlock

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 9 deletions

diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 25f6cca79e6b..bcd971915969 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -793,10 +793,10 @@ static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
         }
         spin_unlock_bh(&im->mca_lock);
 
-        write_lock_bh(&idev->mc_lock);
+        spin_lock_bh(&idev->mc_lock);
         pmc->next = idev->mc_tomb;
         idev->mc_tomb = pmc;
-        write_unlock_bh(&idev->mc_lock);
+        spin_unlock_bh(&idev->mc_lock);
 }
 
 static void mld_del_delrec(struct inet6_dev *idev, struct in6_addr *pmca)
@@ -804,7 +804,7 @@ static void mld_del_delrec(struct inet6_dev *idev, struct in6_addr *pmca)
         struct ifmcaddr6 *pmc, *pmc_prev;
         struct ip6_sf_list *psf, *psf_next;
 
-        write_lock_bh(&idev->mc_lock);
+        spin_lock_bh(&idev->mc_lock);
         pmc_prev = NULL;
         for (pmc=idev->mc_tomb; pmc; pmc=pmc->next) {
                 if (ipv6_addr_equal(&pmc->mca_addr, pmca))
@@ -817,7 +817,8 @@ static void mld_del_delrec(struct inet6_dev *idev, struct in6_addr *pmca)
                 else
                         idev->mc_tomb = pmc->next;
         }
-        write_unlock_bh(&idev->mc_lock);
+        spin_unlock_bh(&idev->mc_lock);
+
         if (pmc) {
                 for (psf=pmc->mca_tomb; psf; psf=psf_next) {
                         psf_next = psf->sf_next;
@@ -832,10 +833,10 @@ static void mld_clear_delrec(struct inet6_dev *idev)
 {
         struct ifmcaddr6 *pmc, *nextpmc;
 
-        write_lock_bh(&idev->mc_lock);
+        spin_lock_bh(&idev->mc_lock);
         pmc = idev->mc_tomb;
         idev->mc_tomb = NULL;
-        write_unlock_bh(&idev->mc_lock);
+        spin_unlock_bh(&idev->mc_lock);
 
         for (; pmc; pmc = nextpmc) {
                 nextpmc = pmc->next;
@@ -1696,7 +1697,7 @@ static void mld_send_cr(struct inet6_dev *idev)
         int type, dtype;
 
         read_lock_bh(&idev->lock);
-        write_lock_bh(&idev->mc_lock);
+        spin_lock(&idev->mc_lock);
 
         /* deleted MCA's */
         pmc_prev = NULL;
@@ -1730,7 +1731,7 @@ static void mld_send_cr(struct inet6_dev *idev)
                 } else
                         pmc_prev = pmc;
         }
-        write_unlock_bh(&idev->mc_lock);
+        spin_unlock(&idev->mc_lock);
 
         /* change recs */
         for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
@@ -2311,7 +2312,7 @@ void ipv6_mc_up(struct inet6_dev *idev)
 void ipv6_mc_init_dev(struct inet6_dev *idev)
 {
         write_lock_bh(&idev->lock);
-        rwlock_init(&idev->mc_lock);
+        spin_lock_init(&idev->mc_lock);
         idev->mc_gq_running = 0;
         setup_timer(&idev->mc_gq_timer, mld_gq_timer_expire,
                         (unsigned long)idev);