From 1447d25eb3a7bbe5bf5e4e7489f09be13e1ec73a Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Fri, 8 Feb 2008 13:03:37 +1100 Subject: [PATCH] knfsd: Remove NLM_HOST_MAX and associated logic. Lockd caches information about hosts that have recently held locks to expedite the taking of further locks. It periodically discards this information for hosts that have not been used for a few minutes. lockd currently has a value NLM_HOST_MAX, and changes the 'garbage collection' behaviour when the number of hosts exceeds this threshold. However its behaviour is strange, and likely not what was intended. When the number of hosts exceeds the max, it scans *less* often (every 2 minutes vs every minute) and allows unused host information to remain around longer (5 minutes instead of 2). Having this limit is of dubious value anyway, and we have not suffered from the code not getting the limit right, so remove the limit altogether. We go with the larger values (discard 5 minute old hosts every 2 minutes) as they are probably safer. Maybe the periodic garbage collection should be replace to with 'shrinker' handler so we just respond to memory pressure.... Acked-by: Jeff Layton Signed-off-by: Neil Brown Signed-off-by: J. Bruce Fields --- fs/lockd/host.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/fs/lockd/host.c b/fs/lockd/host.c index f1ef49fff118..c3f119426d83 100644 --- a/fs/lockd/host.c +++ b/fs/lockd/host.c @@ -19,12 +19,11 @@ #define NLMDBG_FACILITY NLMDBG_HOSTCACHE -#define NLM_HOST_MAX 64 #define NLM_HOST_NRHASH 32 #define NLM_ADDRHASH(addr) (ntohl(addr) & (NLM_HOST_NRHASH-1)) #define NLM_HOST_REBIND (60 * HZ) -#define NLM_HOST_EXPIRE ((nrhosts > NLM_HOST_MAX)? 300 * HZ : 120 * HZ) -#define NLM_HOST_COLLECT ((nrhosts > NLM_HOST_MAX)? 120 * HZ : 60 * HZ) +#define NLM_HOST_EXPIRE (300 * HZ) +#define NLM_HOST_COLLECT (120 * HZ) static struct hlist_head nlm_hosts[NLM_HOST_NRHASH]; static unsigned long next_gc; @@ -142,9 +141,7 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin, INIT_LIST_HEAD(&host->h_granted); INIT_LIST_HEAD(&host->h_reclaim); - if (++nrhosts > NLM_HOST_MAX) - next_gc = 0; - + nrhosts++; out: mutex_unlock(&nlm_host_mutex); return host; -- 2.25.1