GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

svcrdma: Improve allocation of struct svc_rdma_op_ctxt

Browse source 
When the maximum payload size of NFS READ and WRITE was increased
by commit cc9a903d91 ("svcrdma: Change maximum server payload back
to RPCSVC_MAXPAYLOAD"), the size of struct svc_rdma_op_ctxt
increased to over 6KB (on x86_64). That makes allocating one of
these from a kmem_cache more likely to fail in situations when
system memory is exhausted.

Since I'm about to add a caller where this allocation must always
work _and_ it cannot sleep, pre-allocate ctxts for each connection.

Another motivation for this change is that NFSv4.x servers are
required by specification not to drop NFS requests. Pre-allocating
memory resources reduces the likelihood of a drop.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Chuck Lever 2016-01-07 14:49:12 -05:00 • committed by Doug Ledford
parent ced4ac0c4f
commit cc886c9ff1
2 changed files with 94 additions and 14 deletions
Download patch file Download diff file Expand all files Collapse all files

6
include/linux/sunrpc/svc_rdma.h
View file

@ -69,6 +69,7 @@ extern atomic_t rdma_stat_sq_prod;
* completes.
*/
struct svc_rdma_op_ctxt {
struct list_head free;
struct svc_rdma_op_ctxt *read_hdr;
struct svc_rdma_fastreg_mr *frmr;
int hdr_count;
@ -141,7 +142,10 @@ struct svcxprt_rdma {
struct ib_pd *sc_pd;
atomic_t sc_dma_used;
atomic_t sc_ctxt_used;
spinlock_t sc_ctxt_lock;
struct list_head sc_ctxts;
int sc_ctxt_used;
struct list_head sc_rq_dto_q;
spinlock_t sc_rq_dto_lock;
struct ib_qp *sc_qp;