From: "Vishwanathapura, Niranjana" <niranjana.vishwanathapura@intel.com>
Date: Wed, 14 Jun 2017 12:34:42 -0700
Subject: IB/opa_vnic: Use spinlock instead of mutex for stats_lock
Patch-mainline: v4.13-rc1
Git-commit: a379d69f00f28063a7a1c3de235e2996c2c5a6f5
References: bsc#1046306 FATE#322942
Stats can be read from atomic context, hence make stats_lock as
a spinlock.
Fix the following trace with debug kernel.
BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:238
in_atomic(): 1, irqs_disabled(): 0, pid: 6487, name: sadc
Call Trace:
dump_stack+0x63/0x90
___might_sleep+0xda/0x130
__might_sleep+0x4a/0x90
mutex_lock+0x20/0x50
opa_vnic_get_stats64+0x56/0x140 [opa_vnic]
dev_get_stats+0x74/0x130
dev_seq_printf_stats+0x37/0x120
dev_seq_show+0x14/0x30
seq_read+0x26d/0x3d0
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/infiniband/ulp/opa_vnic/opa_vnic_ethtool.c | 4 ++--
drivers/infiniband/ulp/opa_vnic/opa_vnic_internal.h | 2 +-
drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c | 8 +++-----
drivers/infiniband/ulp/opa_vnic/opa_vnic_vema_iface.c | 8 ++++----
4 files changed, 10 insertions(+), 12 deletions(-)
--- a/drivers/infiniband/ulp/opa_vnic/opa_vnic_ethtool.c
+++ b/drivers/infiniband/ulp/opa_vnic/opa_vnic_ethtool.c
@@ -146,15 +146,15 @@ static void vnic_get_ethtool_stats(struc
int i;
memset(&vstats, 0, sizeof(vstats));
- mutex_lock(&adapter->stats_lock);
+ spin_lock(&adapter->stats_lock);
adapter->rn_ops->ndo_get_stats64(netdev, &vstats.netstats);
+ spin_unlock(&adapter->stats_lock);
for (i = 0; i < VNIC_STATS_LEN; i++) {
char *p = (char *)&vstats + vnic_gstrings_stats[i].stat_offset;
data[i] = (vnic_gstrings_stats[i].sizeof_stat ==
sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
}
- mutex_unlock(&adapter->stats_lock);
}
/* vnic_get_strings - get strings */
--- a/drivers/infiniband/ulp/opa_vnic/opa_vnic_internal.h
+++ b/drivers/infiniband/ulp/opa_vnic/opa_vnic_internal.h
@@ -214,7 +214,7 @@ struct opa_vnic_adapter {
struct mutex mactbl_lock;
/* Lock used to protect access to vnic counters */
- struct mutex stats_lock;
+ spinlock_t stats_lock;
u8 flow_tbl[OPA_VNIC_FLOW_TBL_SIZE];
--- a/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c
+++ b/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c
@@ -69,9 +69,9 @@ static void opa_vnic_get_stats64(struct
struct opa_vnic_stats vstats;
memset(&vstats, 0, sizeof(vstats));
- mutex_lock(&adapter->stats_lock);
+ spin_lock(&adapter->stats_lock);
adapter->rn_ops->ndo_get_stats64(netdev, &vstats.netstats);
- mutex_unlock(&adapter->stats_lock);
+ spin_unlock(&adapter->stats_lock);
memcpy(stats, &vstats.netstats, sizeof(*stats));
}
@@ -344,7 +344,7 @@ struct opa_vnic_adapter *opa_vnic_add_ne
netdev->hard_header_len += OPA_VNIC_SKB_HEADROOM;
mutex_init(&adapter->lock);
mutex_init(&adapter->mactbl_lock);
- mutex_init(&adapter->stats_lock);
+ spin_lock_init(&adapter->stats_lock);
SET_NETDEV_DEV(netdev, ibdev->dev.parent);
@@ -364,7 +364,6 @@ struct opa_vnic_adapter *opa_vnic_add_ne
netdev_err:
mutex_destroy(&adapter->lock);
mutex_destroy(&adapter->mactbl_lock);
- mutex_destroy(&adapter->stats_lock);
kfree(adapter);
adapter_err:
ibdev->free_rdma_netdev(netdev);
@@ -383,7 +382,6 @@ void opa_vnic_rem_netdev(struct opa_vnic
opa_vnic_release_mac_tbl(adapter);
mutex_destroy(&adapter->lock);
mutex_destroy(&adapter->mactbl_lock);
- mutex_destroy(&adapter->stats_lock);
kfree(adapter);
ibdev->free_rdma_netdev(netdev);
}
--- a/drivers/infiniband/ulp/opa_vnic/opa_vnic_vema_iface.c
+++ b/drivers/infiniband/ulp/opa_vnic/opa_vnic_vema_iface.c
@@ -89,9 +89,9 @@ void opa_vnic_get_summary_counters(struc
u64 *src;
memset(&vstats, 0, sizeof(vstats));
- mutex_lock(&adapter->stats_lock);
+ spin_lock(&adapter->stats_lock);
adapter->rn_ops->ndo_get_stats64(adapter->netdev, &vstats.netstats);
- mutex_unlock(&adapter->stats_lock);
+ spin_unlock(&adapter->stats_lock);
cntrs->vp_instance = cpu_to_be16(adapter->vport_num);
cntrs->vesw_id = cpu_to_be16(adapter->info.vesw.vesw_id);
@@ -128,9 +128,9 @@ void opa_vnic_get_error_counters(struct
struct opa_vnic_stats vstats;
memset(&vstats, 0, sizeof(vstats));
- mutex_lock(&adapter->stats_lock);
+ spin_lock(&adapter->stats_lock);
adapter->rn_ops->ndo_get_stats64(adapter->netdev, &vstats.netstats);
- mutex_unlock(&adapter->stats_lock);
+ spin_unlock(&adapter->stats_lock);
cntrs->vp_instance = cpu_to_be16(adapter->vport_num);
cntrs->vesw_id = cpu_to_be16(adapter->info.vesw.vesw_id);