From 2bea90d43a050bbc4021d44e59beb34f384438db Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 29 Mar 2007 16:47:53 -0400 Subject: SUNRPC: RPC buffer size estimates are too large The RPC buffer size estimation logic in net/sunrpc/clnt.c always significantly overestimates the requirements for the buffer size. A little instrumentation demonstrated that in fact rpc_malloc was never allocating the buffer from the mempool, but almost always called kmalloc. To compute the size of the RPC buffer more precisely, split p_bufsiz into two fields; one for the argument size, and one for the result size. Then, compute the sum of the exact call and reply header sizes, and split the RPC buffer precisely between the two. That should keep almost all RPC buffers within the 2KiB buffer mempool limit. And, we can finally be rid of RPC_SLACK_SPACE! Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/nfs2xdr.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'fs/nfs/nfs2xdr.c') diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c index 3be4e72a0227..abd9f8b48943 100644 --- a/fs/nfs/nfs2xdr.c +++ b/fs/nfs/nfs2xdr.c @@ -687,16 +687,13 @@ nfs_stat_to_errno(int stat) return nfs_errtbl[i].errno; } -#ifndef MAX -# define MAX(a, b) (((a) > (b))? (a) : (b)) -#endif - #define PROC(proc, argtype, restype, timer) \ [NFSPROC_##proc] = { \ .p_proc = NFSPROC_##proc, \ .p_encode = (kxdrproc_t) nfs_xdr_##argtype, \ .p_decode = (kxdrproc_t) nfs_xdr_##restype, \ - .p_bufsiz = MAX(NFS_##argtype##_sz,NFS_##restype##_sz) << 2, \ + .p_arglen = NFS_##argtype##_sz, \ + .p_replen = NFS_##restype##_sz, \ .p_timer = timer, \ .p_statidx = NFSPROC_##proc, \ .p_name = #proc, \ -- cgit v1.2.2