[ Upstream commit de766e570413bd0484af0b580299b495ada625c3 ] Instead of granting client's full requests until we hit our DRC size limit and then failing CREATE_SESSIONs (and hence mounts) completely, start granting clients smaller slot tables as we approach the limit. The factor chosen here is pretty much arbitrary. Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/nfsd/nfs4state.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 3656f87d11e3..0aacd1c850c3 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -1507,6 +1507,11 @@ static u32 nfsd4_get_drc_mem(struct nfsd4_channel_attrs *ca) spin_lock(&nfsd_drc_lock); avail = min((unsigned long)NFSD_MAX_MEM_PER_SESSION, nfsd_drc_max_mem - nfsd_drc_mem_used); + /* + * Never use more than a third of the remaining memory, + * unless it's the only way to give this client a slot: + */ + avail = clamp_t(int, avail, slotsize, avail/3); num = min_t(int, num, avail / slotsize); nfsd_drc_mem_used += num * slotsize; spin_unlock(&nfsd_drc_lock); -- 2.20.1
