diff options
| -rw-r--r-- | fs/nfsd/nfs4state.c | 66 | ||||
| -rw-r--r-- | include/linux/nfsd/state.h | 8 |
2 files changed, 54 insertions, 20 deletions
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index b44a2cf..02b3ddd 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -414,34 +414,64 @@ gen_sessionid(struct nfsd4_session *ses) } /* - * Give the client the number of slots it requests bound by - * NFSD_MAX_SLOTS_PER_SESSION and by nfsd_drc_max_mem. + * The protocol defines ca_maxresponssize_cached to include the size of + * the rpc header, but all we need to cache is the data starting after + * the end of the initial SEQUENCE operation--the rest we regenerate + * each time. Therefore we can advertise a ca_maxresponssize_cached + * value that is the number of bytes in our cache plus a few additional + * bytes. In order to stay on the safe side, and not promise more than + * we can cache, those additional bytes must be the minimum possible: 24 + * bytes of rpc header (xid through accept state, with AUTH_NULL + * verifier), 12 for the compound header (with zero-length tag), and 44 + * for the SEQUENCE op response: + */ +#define NFSD_MIN_HDR_SEQ_SZ (24 + 12 + 44) + +/* + * Give the client the number of ca_maxresponsesize_cached slots it + * requests, of size bounded by NFSD_SLOT_CACHE_SIZE, + * NFSD_MAX_MEM_PER_SESSION, and nfsd_drc_max_mem. Do not allow more + * than NFSD_MAX_SLOTS_PER_SESSION. * - * If we run out of reserved DRC memory we should (up to a point) re-negotiate - * active sessions and reduce their slot usage to make rooom for new - * connections. For now we just fail the create session. + * If we run out of reserved DRC memory we should (up to a point) + * re-negotiate active sessions and reduce their slot usage to make + * rooom for new connections. For now we just fail the create session. */ -static int set_forechannel_maxreqs(struct nfsd4_channel_attrs *fchan) +static int set_forechannel_drc_size(struct nfsd4_channel_attrs *fchan) { - int mem; + int mem, size = fchan->maxresp_cached; if (fchan->maxreqs < 1) return nfserr_inval; - else if (fchan->maxreqs > NFSD_MAX_SLOTS_PER_SESSION) - fchan->maxreqs = NFSD_MAX_SLOTS_PER_SESSION; - mem = fchan->maxreqs * NFSD_SLOT_CACHE_SIZE; + if (size < NFSD_MIN_HDR_SEQ_SZ) + size = NFSD_MIN_HDR_SEQ_SZ; + size -= NFSD_MIN_HDR_SEQ_SZ; + if (size > NFSD_SLOT_CACHE_SIZE) + size = NFSD_SLOT_CACHE_SIZE; + + /* bound the maxreqs by NFSD_MAX_MEM_PER_SESSION */ + mem = fchan->maxreqs * size; + if (mem > NFSD_MAX_MEM_PER_SESSION) { + fchan->maxreqs = NFSD_MAX_MEM_PER_SESSION / size; + if (fchan->maxreqs > NFSD_MAX_SLOTS_PER_SESSION) + fchan->maxreqs = NFSD_MAX_SLOTS_PER_SESSION; + mem = fchan->maxreqs * size; + } spin_lock(&nfsd_drc_lock); - if (mem + nfsd_drc_mem_used > nfsd_drc_max_mem) - mem = ((nfsd_drc_max_mem - nfsd_drc_mem_used) / - NFSD_SLOT_CACHE_SIZE) * NFSD_SLOT_CACHE_SIZE; + /* bound the total session drc memory ussage */ + if (mem + nfsd_drc_mem_used > nfsd_drc_max_mem) { + fchan->maxreqs = (nfsd_drc_max_mem - nfsd_drc_mem_used) / size; + mem = fchan->maxreqs * size; + } nfsd_drc_mem_used += mem; spin_unlock(&nfsd_drc_lock); - fchan->maxreqs = mem / NFSD_SLOT_CACHE_SIZE; if (fchan->maxreqs == 0) return nfserr_resource; + + fchan->maxresp_cached = size + NFSD_MIN_HDR_SEQ_SZ; return 0; } @@ -466,9 +496,6 @@ static int init_forechannel_attrs(struct svc_rqst *rqstp, fchan->maxresp_sz = maxcount; session_fchan->maxresp_sz = fchan->maxresp_sz; - session_fchan->maxresp_cached = NFSD_SLOT_CACHE_SIZE; - fchan->maxresp_cached = session_fchan->maxresp_cached; - /* Use the client's maxops if possible */ if (fchan->maxops > NFSD_MAX_OPS_PER_COMPOUND) fchan->maxops = NFSD_MAX_OPS_PER_COMPOUND; @@ -478,9 +505,12 @@ static int init_forechannel_attrs(struct svc_rqst *rqstp, * recover pages from existing sessions. For now fail session * creation. */ - status = set_forechannel_maxreqs(fchan); + status = set_forechannel_drc_size(fchan); + session_fchan->maxresp_cached = fchan->maxresp_cached; session_fchan->maxreqs = fchan->maxreqs; + + dprintk("%s status %d\n", __func__, status); return status; } diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h index fb0c404..ff0b771 100644 --- a/include/linux/nfsd/state.h +++ b/include/linux/nfsd/state.h @@ -92,13 +92,17 @@ struct nfs4_cb_conn { struct rpc_cred * cb_cred; }; -/* Maximum number of slots per session. 128 is useful for long haul TCP */ -#define NFSD_MAX_SLOTS_PER_SESSION 128 +/* Maximum number of slots per session. 160 is useful for long haul TCP */ +#define NFSD_MAX_SLOTS_PER_SESSION 160 /* Maximum number of pages per slot cache entry */ #define NFSD_PAGES_PER_SLOT 1 #define NFSD_SLOT_CACHE_SIZE PAGE_SIZE /* Maximum number of operations per session compound */ #define NFSD_MAX_OPS_PER_COMPOUND 16 +/* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */ +#define NFSD_CACHE_SIZE_SLOTS_PER_SESSION 32 +#define NFSD_MAX_MEM_PER_SESSION \ + (NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE) struct nfsd4_cache_entry { __be32 ce_status; |