On Fri, 2025-05-09 at 15:03 -0400, cel@xxxxxxxxxx wrote: > From: Chuck Lever <chuck.lever@xxxxxxxxxx> > > In order to make RPCSVC_MAXPAYLOAD larger (or variable in size), we > need to do something clever with the payload arrays embedded in > struct svc_rqst and elsewhere. > > My preference is to keep these arrays allocated all the time because > allocating them on demand increases the risk of a memory allocation > failure during a large I/O. This is a quick-and-dirty approach that > might be replaced once NFSD is converted to use large folios. > > The downside of this design choice is that it pins a few pages per > NFSD thread (and that's the current situation already). But note > that because RPCSVC_MAXPAGES is 259, each array is just over a page > in size, making the allocation waste quite a bit of memory beyond > the end of the array due to power-of-2 allocator round up. This gets > worse as the MAXPAGES value is doubled or quadrupled. > > This series also addresses similar issues in the socket and RDMA > transports. > > Changes since v4: > * Replace the use of rq_vec instead of allocating it dynamically > > Changes since v3: > * Improved the rdma_rw context count estimate > * Dropped "NFSD: Remove NFSSVC_MAXBLKSIZE from .pc_xdrressize" > * Cleaned up the max size macros a bit > * Completed the implementation of adjustable max_block_size > > Changes since v2: > * Address Jeff's review comments > * Address Neil's review comments > * Start removing a few uses of NFSSVC_MAXBLKSIZE > > Chuck Lever (19): > svcrdma: Reduce the number of rdma_rw contexts per-QP > sunrpc: Add a helper to derive maxpages from sv_max_mesg > sunrpc: Remove backchannel check in svc_init_buffer() > sunrpc: Replace the rq_pages array with dynamically-allocated memory > sunrpc: Replace the rq_bvec array with dynamically-allocated memory > NFSD: Use rqstp->rq_bvec in nfsd_iter_read() > NFSD: De-duplicate the svc_fill_write_vector() call sites > SUNRPC: Export xdr_buf_to_bvec() > NFSD: Use rqstp->rq_bvec in nfsd_iter_write() > SUNRPC: Remove svc_fill_write_vector() > SUNRPC: Remove svc_rqst :: rq_vec > sunrpc: Adjust size of socket's receive page array dynamically > svcrdma: Adjust the number of entries in svc_rdma_recv_ctxt::rc_pages > svcrdma: Adjust the number of entries in svc_rdma_send_ctxt::sc_pages > sunrpc: Remove the RPCSVC_MAXPAGES macro > NFSD: Remove NFSD_BUFSIZE > NFSD: Remove NFSSVC_MAXBLKSIZE_V2 macro > NFSD: Add a "default" block size > SUNRPC: Bump the maximum payload size for the server > > fs/nfsd/nfs3proc.c | 5 +- > fs/nfsd/nfs4proc.c | 10 +-- > fs/nfsd/nfs4state.c | 2 +- > fs/nfsd/nfs4xdr.c | 2 +- > fs/nfsd/nfsd.h | 24 +++---- > fs/nfsd/nfsproc.c | 13 ++-- > fs/nfsd/nfssvc.c | 2 +- > fs/nfsd/nfsxdr.c | 4 +- > fs/nfsd/vfs.c | 67 ++++++++++++++------ > fs/nfsd/vfs.h | 10 +-- > include/linux/sunrpc/svc.h | 46 ++++++++------ > include/linux/sunrpc/svc_rdma.h | 6 +- > include/linux/sunrpc/svcsock.h | 4 +- > net/sunrpc/svc.c | 80 +++++++----------------- > net/sunrpc/svc_xprt.c | 10 +-- > net/sunrpc/svcsock.c | 15 +++-- > net/sunrpc/xdr.c | 1 + > net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 8 ++- > net/sunrpc/xprtrdma/svc_rdma_rw.c | 2 +- > net/sunrpc/xprtrdma/svc_rdma_sendto.c | 16 ++++- > net/sunrpc/xprtrdma/svc_rdma_transport.c | 14 +++-- > 21 files changed, 170 insertions(+), 171 deletions(-) This all looks good to me. You can add this to 8-10 and 18: Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
