While testing NFSD for-next, I noticed svc_generic_init_request() was an unexpected hot spot on NFSv4 workloads. Drilling into the perf report, it shows that the hot path in there is: 1208 memset(rqstp->rq_argp, 0, procp->pc_argsize); 1209 memset(rqstp->rq_resp, 0, procp->pc_ressize); For an NFSv4 COMPOUND, procp->pc_argsize = sizeof(nfsd4_compoundargs), struct nfsd4_compoundargs on my system is more than 17KB! This is due to the size of the iops field: struct nfsd4_op iops[8]; Each struct nfsd4_op contains a union of the arguments for each NFSv4 operation. Each argument is typically less than 128 bytes except that struct nfsd4_copy and struct nfsd4_copy_notify are both larger than 2KB each. Changes since v1: - Fix a compile-time bug spotted by the kernel 0-day robot - Fix a crasher reported by Dai, then by Olga - Add two more clean-up patches --- Chuck Lever (13): NFSD: Fix strncpy() fortify warning NFSD: nfserrno(-ENOMEM) is nfserr_jukebox NFSD: Shrink size of struct nfsd4_copy_notify NFSD: Shrink size of struct nfsd4_copy NFSD: Reorder the fields in struct nfsd4_op NFSD: Make nfs4_put_copy() static NFSD: Make boolean fields in struct nfsd4_copy into atomic bit flags NFSD: Refactor nfsd4_cleanup_inter_ssc() (1/2) NFSD: Refactor nfsd4_cleanup_inter_ssc() (2/2) NFSD: Refactor nfsd4_do_copy() NFSD: Remove kmalloc from nfsd4_do_async_copy() NFSD: Add nfsd4_send_cb_offload() NFSD: Move copy offload callback arguments into a separate structure fs/nfsd/nfs4callback.c | 37 +++++---- fs/nfsd/nfs4proc.c | 169 ++++++++++++++++++++-------------------- fs/nfsd/nfs4xdr.c | 33 +++++--- fs/nfsd/state.h | 1 - fs/nfsd/xdr4.h | 54 +++++++++---- include/linux/nfs_ssc.h | 2 +- 6 files changed, 167 insertions(+), 129 deletions(-) -- Chuck Lever