For presenting statistics relating to duplicate reply cache.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
 void   nfsd_reply_cache_shutdown(void);
 int    nfsd_cache_lookup(struct svc_rqst *);
 void   nfsd_cache_update(struct svc_rqst *, int, __be32 *);
+int    nfsd_reply_cache_stats_open(struct inode *, struct file *);
 
 #ifdef CONFIG_NFSD_V4
 void   nfsd4_set_statp(struct svc_rqst *rqstp, __be32 *statp);
 
        vec->iov_len += data->iov_len;
        return 1;
 }
+
+/*
+ * Note that fields may be added, removed or reordered in the future. Programs
+ * scraping this file for info should test the labels to ensure they're
+ * getting the correct field.
+ */
+static int nfsd_reply_cache_stats_show(struct seq_file *m, void *v)
+{
+       spin_lock(&cache_lock);
+       seq_printf(m, "max entries:           %u\n", max_drc_entries);
+       seq_printf(m, "num entries:           %u\n", num_drc_entries);
+       seq_printf(m, "hash buckets:          %u\n", HASHSIZE);
+       seq_printf(m, "mem usage:             %u\n", drc_mem_usage);
+       seq_printf(m, "cache hits:            %u\n", nfsdstats.rchits);
+       seq_printf(m, "cache misses:          %u\n", nfsdstats.rcmisses);
+       seq_printf(m, "not cached:            %u\n", nfsdstats.rcnocache);
+       seq_printf(m, "payload misses:        %u\n", payload_misses);
+       spin_unlock(&cache_lock);
+       return 0;
+}
+
+int nfsd_reply_cache_stats_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, nfsd_reply_cache_stats_show, NULL);
+}
 
        NFSD_Threads,
        NFSD_Pool_Threads,
        NFSD_Pool_Stats,
+       NFSD_Reply_Cache_Stats,
        NFSD_Versions,
        NFSD_Ports,
        NFSD_MaxBlkSize,
        .owner          = THIS_MODULE,
 };
 
+static struct file_operations reply_cache_stats_operations = {
+       .open           = nfsd_reply_cache_stats_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
 /*----------------------------------------------------------------------------*/
 /*
  * payload - write methods
                [NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
                [NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
                [NFSD_Pool_Stats] = {"pool_stats", &pool_stats_operations, S_IRUGO},
+               [NFSD_Reply_Cache_Stats] = {"reply_cache_stats", &reply_cache_stats_operations, S_IRUGO},
                [NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
                [NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
                [NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},