The purpose of mc_lock is to protect inet6_dev->mc_tomb. But mc_tomb is already protected by RTNL and all functions, which manipulate mc_tomb are called under RTNL. So, mc_lock is not needed. Furthermore, it is spinlock so the critical section is atomic. In order to reduce atomic context, it should be removed.
Suggested-by: Cong Wang xiyou.wangcong@gmail.com Signed-off-by: Taehee Yoo ap420073@gmail.com --- v2 -> v3: - No change v1 -> v2: - Separated from previous big one patch.
include/net/if_inet6.h | 1 - net/ipv6/mcast.c | 9 --------- 2 files changed, 10 deletions(-)
diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h index af5244c9ca5c..1080d2248304 100644 --- a/include/net/if_inet6.h +++ b/include/net/if_inet6.h @@ -167,7 +167,6 @@ struct inet6_dev {
struct ifmcaddr6 *mc_list; struct ifmcaddr6 *mc_tomb; - spinlock_t mc_lock;
unsigned char mc_qrv; /* Query Robustness Variable */ unsigned char mc_gq_running; diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index 692a6dec8959..35962aa3cc22 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -752,10 +752,8 @@ static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im) } spin_unlock_bh(&im->mca_lock);
- spin_lock_bh(&idev->mc_lock); pmc->next = idev->mc_tomb; idev->mc_tomb = pmc; - spin_unlock_bh(&idev->mc_lock); }
static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im) @@ -764,7 +762,6 @@ static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im) struct ip6_sf_list *psf; struct in6_addr *pmca = &im->mca_addr;
- 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)) @@ -777,7 +774,6 @@ static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im) else idev->mc_tomb = pmc->next; } - spin_unlock_bh(&idev->mc_lock);
spin_lock_bh(&im->mca_lock); if (pmc) { @@ -801,10 +797,8 @@ static void mld_clear_delrec(struct inet6_dev *idev) { struct ifmcaddr6 *pmc, *nextpmc;
- spin_lock_bh(&idev->mc_lock); pmc = idev->mc_tomb; idev->mc_tomb = NULL; - spin_unlock_bh(&idev->mc_lock);
for (; pmc; pmc = nextpmc) { nextpmc = pmc->next; @@ -1907,7 +1901,6 @@ static void mld_send_cr(struct inet6_dev *idev) int type, dtype;
read_lock_bh(&idev->lock); - spin_lock(&idev->mc_lock);
/* deleted MCA's */ pmc_prev = NULL; @@ -1941,7 +1934,6 @@ static void mld_send_cr(struct inet6_dev *idev) } else pmc_prev = pmc; } - spin_unlock(&idev->mc_lock);
/* change recs */ for (pmc = idev->mc_list; pmc; pmc = pmc->next) { @@ -2582,7 +2574,6 @@ void ipv6_mc_up(struct inet6_dev *idev) void ipv6_mc_init_dev(struct inet6_dev *idev) { write_lock_bh(&idev->lock); - spin_lock_init(&idev->mc_lock); idev->mc_gq_running = 0; INIT_DELAYED_WORK(&idev->mc_gq_work, mld_gq_work); idev->mc_tomb = NULL;