| Message ID | 20220907033604.4637-1-zeming@nfschina.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | rdma/rdmavt_qp: Remove unnecessary 'NULL' values from qp | expand |
On Wed, Sep 07, 2022 at 11:36:04AM +0800, Li zeming wrote: > The pointer qp is assigned before it is used, it does not need to be > initialized and assigned. > > Signed-off-by: Li zeming <zeming@nfschina.com> > --- > include/rdma/rdmavt_qp.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/rdma/rdmavt_qp.h b/include/rdma/rdmavt_qp.h > index 2e58d5e6ac0e..2afc3300d618 100644 > --- a/include/rdma/rdmavt_qp.h > +++ b/include/rdma/rdmavt_qp.h > @@ -699,7 +699,7 @@ static inline struct rvt_qp *rvt_lookup_qpn(struct rvt_dev_info *rdi, > struct rvt_ibport *rvp, > u32 qpn) __must_hold(RCU) > { > - struct rvt_qp *qp = NULL; > + struct rvt_qp *qp; > > if (unlikely(qpn <= 1)) { > qp = rcu_dereference(rvp->qp[qpn]); This function is completely wrong, most likely it never returns NULL otherwise, we would crash in "if (qp->ibqp.qp_num == qpn)" line. The proper change will be something like this: diff --git a/include/rdma/rdmavt_qp.h b/include/rdma/rdmavt_qp.h index 2e58d5e6ac0e..883c328e06b6 100644 --- a/include/rdma/rdmavt_qp.h +++ b/include/rdma/rdmavt_qp.h @@ -699,19 +699,19 @@ static inline struct rvt_qp *rvt_lookup_qpn(struct rvt_dev_info *rdi, struct rvt_ibport *rvp, u32 qpn) __must_hold(RCU) { - struct rvt_qp *qp = NULL; + struct rvt_qp *qp; + u32 n; - if (unlikely(qpn <= 1)) { - qp = rcu_dereference(rvp->qp[qpn]); - } else { - u32 n = hash_32(qpn, rdi->qp_dev->qp_table_bits); + if (unlikely(qpn <= 1)) + return rcu_dereference(rvp->qp[qpn]); - for (qp = rcu_dereference(rdi->qp_dev->qp_table[n]); qp; - qp = rcu_dereference(qp->next)) - if (qp->ibqp.qp_num == qpn) - break; - } - return qp; + n = hash_32(qpn, rdi->qp_dev->qp_table_bits); + + for (qp = rcu_dereference(rdi->qp_dev->qp_table[n]); qp; + qp = rcu_dereference(qp->next)) + if (qp->ibqp.qp_num == qpn) + return qp; + return NULL; } /** > -- > 2.18.2 >
diff --git a/include/rdma/rdmavt_qp.h b/include/rdma/rdmavt_qp.h index 2e58d5e6ac0e..2afc3300d618 100644 --- a/include/rdma/rdmavt_qp.h +++ b/include/rdma/rdmavt_qp.h @@ -699,7 +699,7 @@ static inline struct rvt_qp *rvt_lookup_qpn(struct rvt_dev_info *rdi, struct rvt_ibport *rvp, u32 qpn) __must_hold(RCU) { - struct rvt_qp *qp = NULL; + struct rvt_qp *qp; if (unlikely(qpn <= 1)) { qp = rcu_dereference(rvp->qp[qpn]);
The pointer qp is assigned before it is used, it does not need to be initialized and assigned. Signed-off-by: Li zeming <zeming@nfschina.com> --- include/rdma/rdmavt_qp.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)