Commit 9594497f authored Nov 04, 2019 by Arnd Bergmann Committed by J. Bruce Fields Dec 19, 2019

nfsd: fix jiffies/time_t mixup in LRU list



The nfsd4_blocked_lock->nbl_time timestamp is recorded in jiffies,
but then compared to a CLOCK_REALTIME timestamp later on, which makes
no sense.

For consistency with the other timestamps, change this to use a time_t.

This is a change in behavior, which may cause regressions, but the
current code is not sensible. On a system with CONFIG_HZ=1000,
the 'time_after((unsigned long)nbl->nbl_time, (unsigned long)cutoff))'
check is false for roughly the first 18 days of uptime and then true
for the next 49 days.

Fixes: 7919d0a2 ("nfsd: add a LRU list for blocked locks")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

parent 2561c92b

fs/nfsd/nfs4state.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -6700,7 +6700,7 @@ nfsd4_lock(struct svc_rqst rqstp, struct nfsd4_compound_state cstate,
		}

		if (fl_flags & FL_SLEEP) {
		nbl->nbl_time = jiffies;
		nbl->nbl_time = get_seconds();
		spin_lock(&nn->blocked_locks_lock);
		list_add_tail(&nbl->nbl_list, &lock_sop->lo_blocked);
		list_add_tail(&nbl->nbl_lru, &nn->blocked_locks_lru);

fs/nfsd/state.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -626,7 +626,7 @@ static inline bool nfsd4_stateid_generation_after(stateid_t a, stateid_t b)
		struct nfsd4_blocked_lock {
		struct list_head nbl_list;
		struct list_head nbl_lru;
		unsigned long nbl_time;
		time_t nbl_time;
		struct file_lock nbl_lock;
		struct knfsd_fh nbl_fh;
		struct nfsd4_callback nbl_cb;

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