nfsd41: replace page based DRC with buffer based DRC
Use NFSD_SLOT_CACHE_SIZE size buffers for sessions DRC instead of holding nfsd
pages in cache.
Connectathon testing has shown that 1024 bytes for encoded compound operation
responses past the sequence operation is sufficient, 512 bytes is a little too
small. Set NFSD_SLOT_CACHE_SIZE to 1024.
Allocate memory for the session DRC in the CREATE_SESSION operation
to guarantee that the memory resource is available for caching responses.
Allocate each slot individually in preparation for slot table size negotiation.
Remove struct nfsd4_cache_entry and helper functions for the old page-based
DRC.
The iov_len calculation in nfs4svc_encode_compoundres is now always
correct. Replay is now done in nfsd4_sequence under the state lock, so
the session ref count is only bumped on non-replay. Clean up the
nfs4svc_encode_compoundres session logic.
The nfsd4_compound_state statp pointer is also not used.
Remove nfsd4_set_statp().
Move useful nfsd4_cache_entry fields into nfsd4_slot.
Signed-off-by: Andy Adamson <andros@netapp.com
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h
index ff0b771..70ef5f4 100644
--- a/include/linux/nfsd/state.h
+++ b/include/linux/nfsd/state.h
@@ -94,30 +94,23 @@
/* 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 session per slot cache size */
+#define NFSD_SLOT_CACHE_SIZE 1024
/* 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;
- struct kvec ce_datav; /* encoded NFSv4.1 data in rq_res.head[0] */
- struct page *ce_respages[NFSD_PAGES_PER_SLOT + 1];
- int ce_cachethis;
- short ce_resused;
- int ce_opcnt;
- int ce_rpchdrlen;
-};
-
struct nfsd4_slot {
- bool sl_inuse;
- u32 sl_seqid;
- struct nfsd4_cache_entry sl_cache_entry;
+ bool sl_inuse;
+ bool sl_cachethis;
+ u16 sl_opcnt;
+ u32 sl_seqid;
+ __be32 sl_status;
+ u32 sl_datalen;
+ char sl_data[];
};
struct nfsd4_channel_attrs {
@@ -159,7 +152,7 @@
struct nfs4_sessionid se_sessionid;
struct nfsd4_channel_attrs se_fchannel;
struct nfsd4_channel_attrs se_bchannel;
- struct nfsd4_slot se_slots[]; /* forward channel slots */
+ struct nfsd4_slot *se_slots[]; /* forward channel slots */
};
static inline void