192d80cdcb
Use the new KMEM_CACHE() macro instead of direct kmem_cache_create to simplify the creation of SLAB caches. And change cache name from 'nfsd_drc' to 'nfsd_cacherep'. Signed-off-by: Kunwu Chan <chentao@kylinos.cn> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
680 lines
19 KiB
C
680 lines
19 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Request reply cache. This is currently a global cache, but this may
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* change in the future and be a per-client cache.
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*
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* This code is heavily inspired by the 44BSD implementation, although
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* it does things a bit differently.
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*
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* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
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*/
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#include <linux/sunrpc/svc_xprt.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <linux/sunrpc/addr.h>
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#include <linux/highmem.h>
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#include <linux/log2.h>
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#include <linux/hash.h>
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#include <net/checksum.h>
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#include "nfsd.h"
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#include "cache.h"
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#include "trace.h"
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/*
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* We use this value to determine the number of hash buckets from the max
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* cache size, the idea being that when the cache is at its maximum number
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* of entries, then this should be the average number of entries per bucket.
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*/
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#define TARGET_BUCKET_SIZE 64
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struct nfsd_drc_bucket {
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struct rb_root rb_head;
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struct list_head lru_head;
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spinlock_t cache_lock;
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};
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static struct kmem_cache *drc_slab;
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static int nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *vec);
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static unsigned long nfsd_reply_cache_count(struct shrinker *shrink,
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struct shrink_control *sc);
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static unsigned long nfsd_reply_cache_scan(struct shrinker *shrink,
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struct shrink_control *sc);
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/*
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* Put a cap on the size of the DRC based on the amount of available
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* low memory in the machine.
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*
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* 64MB: 8192
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* 128MB: 11585
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* 256MB: 16384
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* 512MB: 23170
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* 1GB: 32768
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* 2GB: 46340
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* 4GB: 65536
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* 8GB: 92681
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* 16GB: 131072
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*
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* ...with a hard cap of 256k entries. In the worst case, each entry will be
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* ~1k, so the above numbers should give a rough max of the amount of memory
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* used in k.
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*
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* XXX: these limits are per-container, so memory used will increase
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* linearly with number of containers. Maybe that's OK.
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*/
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static unsigned int
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nfsd_cache_size_limit(void)
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{
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unsigned int limit;
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unsigned long low_pages = totalram_pages() - totalhigh_pages();
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limit = (16 * int_sqrt(low_pages)) << (PAGE_SHIFT-10);
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return min_t(unsigned int, limit, 256*1024);
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}
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/*
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* Compute the number of hash buckets we need. Divide the max cachesize by
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* the "target" max bucket size, and round up to next power of two.
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*/
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static unsigned int
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nfsd_hashsize(unsigned int limit)
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{
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return roundup_pow_of_two(limit / TARGET_BUCKET_SIZE);
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}
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static struct nfsd_cacherep *
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nfsd_cacherep_alloc(struct svc_rqst *rqstp, __wsum csum,
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struct nfsd_net *nn)
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{
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struct nfsd_cacherep *rp;
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rp = kmem_cache_alloc(drc_slab, GFP_KERNEL);
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if (rp) {
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rp->c_state = RC_UNUSED;
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rp->c_type = RC_NOCACHE;
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RB_CLEAR_NODE(&rp->c_node);
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INIT_LIST_HEAD(&rp->c_lru);
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memset(&rp->c_key, 0, sizeof(rp->c_key));
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rp->c_key.k_xid = rqstp->rq_xid;
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rp->c_key.k_proc = rqstp->rq_proc;
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rpc_copy_addr((struct sockaddr *)&rp->c_key.k_addr, svc_addr(rqstp));
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rpc_set_port((struct sockaddr *)&rp->c_key.k_addr, rpc_get_port(svc_addr(rqstp)));
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rp->c_key.k_prot = rqstp->rq_prot;
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rp->c_key.k_vers = rqstp->rq_vers;
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rp->c_key.k_len = rqstp->rq_arg.len;
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rp->c_key.k_csum = csum;
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}
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return rp;
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}
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static void nfsd_cacherep_free(struct nfsd_cacherep *rp)
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{
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if (rp->c_type == RC_REPLBUFF)
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kfree(rp->c_replvec.iov_base);
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kmem_cache_free(drc_slab, rp);
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}
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static unsigned long
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nfsd_cacherep_dispose(struct list_head *dispose)
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{
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struct nfsd_cacherep *rp;
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unsigned long freed = 0;
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while (!list_empty(dispose)) {
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rp = list_first_entry(dispose, struct nfsd_cacherep, c_lru);
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list_del(&rp->c_lru);
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nfsd_cacherep_free(rp);
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freed++;
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}
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return freed;
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}
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static void
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nfsd_cacherep_unlink_locked(struct nfsd_net *nn, struct nfsd_drc_bucket *b,
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struct nfsd_cacherep *rp)
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{
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if (rp->c_type == RC_REPLBUFF && rp->c_replvec.iov_base)
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nfsd_stats_drc_mem_usage_sub(nn, rp->c_replvec.iov_len);
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if (rp->c_state != RC_UNUSED) {
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rb_erase(&rp->c_node, &b->rb_head);
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list_del(&rp->c_lru);
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atomic_dec(&nn->num_drc_entries);
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nfsd_stats_drc_mem_usage_sub(nn, sizeof(*rp));
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}
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}
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static void
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nfsd_reply_cache_free_locked(struct nfsd_drc_bucket *b, struct nfsd_cacherep *rp,
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struct nfsd_net *nn)
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{
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nfsd_cacherep_unlink_locked(nn, b, rp);
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nfsd_cacherep_free(rp);
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}
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static void
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nfsd_reply_cache_free(struct nfsd_drc_bucket *b, struct nfsd_cacherep *rp,
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struct nfsd_net *nn)
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{
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spin_lock(&b->cache_lock);
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nfsd_cacherep_unlink_locked(nn, b, rp);
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spin_unlock(&b->cache_lock);
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nfsd_cacherep_free(rp);
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}
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int nfsd_drc_slab_create(void)
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{
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drc_slab = KMEM_CACHE(nfsd_cacherep, 0);
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return drc_slab ? 0: -ENOMEM;
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}
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void nfsd_drc_slab_free(void)
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{
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kmem_cache_destroy(drc_slab);
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}
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int nfsd_reply_cache_init(struct nfsd_net *nn)
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{
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unsigned int hashsize;
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unsigned int i;
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nn->max_drc_entries = nfsd_cache_size_limit();
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atomic_set(&nn->num_drc_entries, 0);
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hashsize = nfsd_hashsize(nn->max_drc_entries);
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nn->maskbits = ilog2(hashsize);
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nn->drc_hashtbl = kvzalloc(array_size(hashsize,
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sizeof(*nn->drc_hashtbl)), GFP_KERNEL);
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if (!nn->drc_hashtbl)
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return -ENOMEM;
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nn->nfsd_reply_cache_shrinker = shrinker_alloc(0, "nfsd-reply:%s",
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nn->nfsd_name);
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if (!nn->nfsd_reply_cache_shrinker)
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goto out_shrinker;
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nn->nfsd_reply_cache_shrinker->scan_objects = nfsd_reply_cache_scan;
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nn->nfsd_reply_cache_shrinker->count_objects = nfsd_reply_cache_count;
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nn->nfsd_reply_cache_shrinker->seeks = 1;
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nn->nfsd_reply_cache_shrinker->private_data = nn;
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shrinker_register(nn->nfsd_reply_cache_shrinker);
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for (i = 0; i < hashsize; i++) {
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INIT_LIST_HEAD(&nn->drc_hashtbl[i].lru_head);
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spin_lock_init(&nn->drc_hashtbl[i].cache_lock);
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}
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nn->drc_hashsize = hashsize;
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return 0;
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out_shrinker:
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kvfree(nn->drc_hashtbl);
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printk(KERN_ERR "nfsd: failed to allocate reply cache\n");
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return -ENOMEM;
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}
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void nfsd_reply_cache_shutdown(struct nfsd_net *nn)
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{
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struct nfsd_cacherep *rp;
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unsigned int i;
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shrinker_free(nn->nfsd_reply_cache_shrinker);
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for (i = 0; i < nn->drc_hashsize; i++) {
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struct list_head *head = &nn->drc_hashtbl[i].lru_head;
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while (!list_empty(head)) {
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rp = list_first_entry(head, struct nfsd_cacherep, c_lru);
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nfsd_reply_cache_free_locked(&nn->drc_hashtbl[i],
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rp, nn);
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}
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}
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kvfree(nn->drc_hashtbl);
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nn->drc_hashtbl = NULL;
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nn->drc_hashsize = 0;
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}
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/*
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* Move cache entry to end of LRU list, and queue the cleaner to run if it's
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* not already scheduled.
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*/
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static void
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lru_put_end(struct nfsd_drc_bucket *b, struct nfsd_cacherep *rp)
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{
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rp->c_timestamp = jiffies;
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list_move_tail(&rp->c_lru, &b->lru_head);
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}
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static noinline struct nfsd_drc_bucket *
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nfsd_cache_bucket_find(__be32 xid, struct nfsd_net *nn)
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{
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unsigned int hash = hash_32((__force u32)xid, nn->maskbits);
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return &nn->drc_hashtbl[hash];
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}
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/*
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* Remove and return no more than @max expired entries in bucket @b.
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* If @max is zero, do not limit the number of removed entries.
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*/
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static void
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nfsd_prune_bucket_locked(struct nfsd_net *nn, struct nfsd_drc_bucket *b,
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unsigned int max, struct list_head *dispose)
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{
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unsigned long expiry = jiffies - RC_EXPIRE;
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struct nfsd_cacherep *rp, *tmp;
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unsigned int freed = 0;
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lockdep_assert_held(&b->cache_lock);
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/* The bucket LRU is ordered oldest-first. */
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list_for_each_entry_safe(rp, tmp, &b->lru_head, c_lru) {
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/*
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* Don't free entries attached to calls that are still
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* in-progress, but do keep scanning the list.
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*/
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if (rp->c_state == RC_INPROG)
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continue;
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if (atomic_read(&nn->num_drc_entries) <= nn->max_drc_entries &&
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time_before(expiry, rp->c_timestamp))
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break;
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nfsd_cacherep_unlink_locked(nn, b, rp);
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list_add(&rp->c_lru, dispose);
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if (max && ++freed > max)
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break;
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}
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}
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/**
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* nfsd_reply_cache_count - count_objects method for the DRC shrinker
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* @shrink: our registered shrinker context
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* @sc: garbage collection parameters
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*
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* Returns the total number of entries in the duplicate reply cache. To
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* keep things simple and quick, this is not the number of expired entries
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* in the cache (ie, the number that would be removed by a call to
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* nfsd_reply_cache_scan).
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*/
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static unsigned long
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nfsd_reply_cache_count(struct shrinker *shrink, struct shrink_control *sc)
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{
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struct nfsd_net *nn = shrink->private_data;
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return atomic_read(&nn->num_drc_entries);
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}
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/**
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* nfsd_reply_cache_scan - scan_objects method for the DRC shrinker
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* @shrink: our registered shrinker context
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* @sc: garbage collection parameters
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*
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* Free expired entries on each bucket's LRU list until we've released
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* nr_to_scan freed objects. Nothing will be released if the cache
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* has not exceeded it's max_drc_entries limit.
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*
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* Returns the number of entries released by this call.
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*/
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static unsigned long
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nfsd_reply_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
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{
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struct nfsd_net *nn = shrink->private_data;
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unsigned long freed = 0;
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LIST_HEAD(dispose);
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unsigned int i;
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for (i = 0; i < nn->drc_hashsize; i++) {
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struct nfsd_drc_bucket *b = &nn->drc_hashtbl[i];
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if (list_empty(&b->lru_head))
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continue;
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spin_lock(&b->cache_lock);
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nfsd_prune_bucket_locked(nn, b, 0, &dispose);
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spin_unlock(&b->cache_lock);
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freed += nfsd_cacherep_dispose(&dispose);
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if (freed > sc->nr_to_scan)
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break;
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}
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return freed;
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}
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/**
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* nfsd_cache_csum - Checksum incoming NFS Call arguments
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* @buf: buffer containing a whole RPC Call message
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* @start: starting byte of the NFS Call header
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* @remaining: size of the NFS Call header, in bytes
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*
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* Compute a weak checksum of the leading bytes of an NFS procedure
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* call header to help verify that a retransmitted Call matches an
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* entry in the duplicate reply cache.
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*
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* To avoid assumptions about how the RPC message is laid out in
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* @buf and what else it might contain (eg, a GSS MIC suffix), the
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* caller passes us the exact location and length of the NFS Call
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* header.
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*
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* Returns a 32-bit checksum value, as defined in RFC 793.
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*/
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static __wsum nfsd_cache_csum(struct xdr_buf *buf, unsigned int start,
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unsigned int remaining)
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{
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unsigned int base, len;
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struct xdr_buf subbuf;
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__wsum csum = 0;
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void *p;
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int idx;
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if (remaining > RC_CSUMLEN)
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remaining = RC_CSUMLEN;
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if (xdr_buf_subsegment(buf, &subbuf, start, remaining))
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return csum;
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/* rq_arg.head first */
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if (subbuf.head[0].iov_len) {
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len = min_t(unsigned int, subbuf.head[0].iov_len, remaining);
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csum = csum_partial(subbuf.head[0].iov_base, len, csum);
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remaining -= len;
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}
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/* Continue into page array */
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idx = subbuf.page_base / PAGE_SIZE;
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base = subbuf.page_base & ~PAGE_MASK;
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while (remaining) {
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p = page_address(subbuf.pages[idx]) + base;
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len = min_t(unsigned int, PAGE_SIZE - base, remaining);
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csum = csum_partial(p, len, csum);
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remaining -= len;
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base = 0;
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++idx;
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}
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return csum;
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}
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static int
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nfsd_cache_key_cmp(const struct nfsd_cacherep *key,
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const struct nfsd_cacherep *rp, struct nfsd_net *nn)
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{
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if (key->c_key.k_xid == rp->c_key.k_xid &&
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key->c_key.k_csum != rp->c_key.k_csum) {
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nfsd_stats_payload_misses_inc(nn);
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trace_nfsd_drc_mismatch(nn, key, rp);
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}
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return memcmp(&key->c_key, &rp->c_key, sizeof(key->c_key));
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}
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/*
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* Search the request hash for an entry that matches the given rqstp.
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* Must be called with cache_lock held. Returns the found entry or
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* inserts an empty key on failure.
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*/
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static struct nfsd_cacherep *
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nfsd_cache_insert(struct nfsd_drc_bucket *b, struct nfsd_cacherep *key,
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struct nfsd_net *nn)
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{
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struct nfsd_cacherep *rp, *ret = key;
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struct rb_node **p = &b->rb_head.rb_node,
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*parent = NULL;
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unsigned int entries = 0;
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int cmp;
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while (*p != NULL) {
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++entries;
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parent = *p;
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rp = rb_entry(parent, struct nfsd_cacherep, c_node);
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cmp = nfsd_cache_key_cmp(key, rp, nn);
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if (cmp < 0)
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p = &parent->rb_left;
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else if (cmp > 0)
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p = &parent->rb_right;
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else {
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ret = rp;
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goto out;
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}
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}
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rb_link_node(&key->c_node, parent, p);
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rb_insert_color(&key->c_node, &b->rb_head);
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out:
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/* tally hash chain length stats */
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if (entries > nn->longest_chain) {
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nn->longest_chain = entries;
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nn->longest_chain_cachesize = atomic_read(&nn->num_drc_entries);
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} else if (entries == nn->longest_chain) {
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/* prefer to keep the smallest cachesize possible here */
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nn->longest_chain_cachesize = min_t(unsigned int,
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nn->longest_chain_cachesize,
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atomic_read(&nn->num_drc_entries));
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}
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lru_put_end(b, ret);
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return ret;
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}
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/**
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* nfsd_cache_lookup - Find an entry in the duplicate reply cache
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* @rqstp: Incoming Call to find
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* @start: starting byte in @rqstp->rq_arg of the NFS Call header
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* @len: size of the NFS Call header, in bytes
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* @cacherep: OUT: DRC entry for this request
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*
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* Try to find an entry matching the current call in the cache. When none
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* is found, we try to grab the oldest expired entry off the LRU list. If
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* a suitable one isn't there, then drop the cache_lock and allocate a
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* new one, then search again in case one got inserted while this thread
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* didn't hold the lock.
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*
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* Return values:
|
|
* %RC_DOIT: Process the request normally
|
|
* %RC_REPLY: Reply from cache
|
|
* %RC_DROPIT: Do not process the request further
|
|
*/
|
|
int nfsd_cache_lookup(struct svc_rqst *rqstp, unsigned int start,
|
|
unsigned int len, struct nfsd_cacherep **cacherep)
|
|
{
|
|
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
|
|
struct nfsd_cacherep *rp, *found;
|
|
__wsum csum;
|
|
struct nfsd_drc_bucket *b;
|
|
int type = rqstp->rq_cachetype;
|
|
LIST_HEAD(dispose);
|
|
int rtn = RC_DOIT;
|
|
|
|
if (type == RC_NOCACHE) {
|
|
nfsd_stats_rc_nocache_inc(nn);
|
|
goto out;
|
|
}
|
|
|
|
csum = nfsd_cache_csum(&rqstp->rq_arg, start, len);
|
|
|
|
/*
|
|
* Since the common case is a cache miss followed by an insert,
|
|
* preallocate an entry.
|
|
*/
|
|
rp = nfsd_cacherep_alloc(rqstp, csum, nn);
|
|
if (!rp)
|
|
goto out;
|
|
|
|
b = nfsd_cache_bucket_find(rqstp->rq_xid, nn);
|
|
spin_lock(&b->cache_lock);
|
|
found = nfsd_cache_insert(b, rp, nn);
|
|
if (found != rp)
|
|
goto found_entry;
|
|
*cacherep = rp;
|
|
rp->c_state = RC_INPROG;
|
|
nfsd_prune_bucket_locked(nn, b, 3, &dispose);
|
|
spin_unlock(&b->cache_lock);
|
|
|
|
nfsd_cacherep_dispose(&dispose);
|
|
|
|
nfsd_stats_rc_misses_inc(nn);
|
|
atomic_inc(&nn->num_drc_entries);
|
|
nfsd_stats_drc_mem_usage_add(nn, sizeof(*rp));
|
|
goto out;
|
|
|
|
found_entry:
|
|
/* We found a matching entry which is either in progress or done. */
|
|
nfsd_reply_cache_free_locked(NULL, rp, nn);
|
|
nfsd_stats_rc_hits_inc(nn);
|
|
rtn = RC_DROPIT;
|
|
rp = found;
|
|
|
|
/* Request being processed */
|
|
if (rp->c_state == RC_INPROG)
|
|
goto out_trace;
|
|
|
|
/* From the hall of fame of impractical attacks:
|
|
* Is this a user who tries to snoop on the cache? */
|
|
rtn = RC_DOIT;
|
|
if (!test_bit(RQ_SECURE, &rqstp->rq_flags) && rp->c_secure)
|
|
goto out_trace;
|
|
|
|
/* Compose RPC reply header */
|
|
switch (rp->c_type) {
|
|
case RC_NOCACHE:
|
|
break;
|
|
case RC_REPLSTAT:
|
|
xdr_stream_encode_be32(&rqstp->rq_res_stream, rp->c_replstat);
|
|
rtn = RC_REPLY;
|
|
break;
|
|
case RC_REPLBUFF:
|
|
if (!nfsd_cache_append(rqstp, &rp->c_replvec))
|
|
goto out_unlock; /* should not happen */
|
|
rtn = RC_REPLY;
|
|
break;
|
|
default:
|
|
WARN_ONCE(1, "nfsd: bad repcache type %d\n", rp->c_type);
|
|
}
|
|
|
|
out_trace:
|
|
trace_nfsd_drc_found(nn, rqstp, rtn);
|
|
out_unlock:
|
|
spin_unlock(&b->cache_lock);
|
|
out:
|
|
return rtn;
|
|
}
|
|
|
|
/**
|
|
* nfsd_cache_update - Update an entry in the duplicate reply cache.
|
|
* @rqstp: svc_rqst with a finished Reply
|
|
* @rp: IN: DRC entry for this request
|
|
* @cachetype: which cache to update
|
|
* @statp: pointer to Reply's NFS status code, or NULL
|
|
*
|
|
* This is called from nfsd_dispatch when the procedure has been
|
|
* executed and the complete reply is in rqstp->rq_res.
|
|
*
|
|
* We're copying around data here rather than swapping buffers because
|
|
* the toplevel loop requires max-sized buffers, which would be a waste
|
|
* of memory for a cache with a max reply size of 100 bytes (diropokres).
|
|
*
|
|
* If we should start to use different types of cache entries tailored
|
|
* specifically for attrstat and fh's, we may save even more space.
|
|
*
|
|
* Also note that a cachetype of RC_NOCACHE can legally be passed when
|
|
* nfsd failed to encode a reply that otherwise would have been cached.
|
|
* In this case, nfsd_cache_update is called with statp == NULL.
|
|
*/
|
|
void nfsd_cache_update(struct svc_rqst *rqstp, struct nfsd_cacherep *rp,
|
|
int cachetype, __be32 *statp)
|
|
{
|
|
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
|
|
struct kvec *resv = &rqstp->rq_res.head[0], *cachv;
|
|
struct nfsd_drc_bucket *b;
|
|
int len;
|
|
size_t bufsize = 0;
|
|
|
|
if (!rp)
|
|
return;
|
|
|
|
b = nfsd_cache_bucket_find(rp->c_key.k_xid, nn);
|
|
|
|
len = resv->iov_len - ((char*)statp - (char*)resv->iov_base);
|
|
len >>= 2;
|
|
|
|
/* Don't cache excessive amounts of data and XDR failures */
|
|
if (!statp || len > (256 >> 2)) {
|
|
nfsd_reply_cache_free(b, rp, nn);
|
|
return;
|
|
}
|
|
|
|
switch (cachetype) {
|
|
case RC_REPLSTAT:
|
|
if (len != 1)
|
|
printk("nfsd: RC_REPLSTAT/reply len %d!\n",len);
|
|
rp->c_replstat = *statp;
|
|
break;
|
|
case RC_REPLBUFF:
|
|
cachv = &rp->c_replvec;
|
|
bufsize = len << 2;
|
|
cachv->iov_base = kmalloc(bufsize, GFP_KERNEL);
|
|
if (!cachv->iov_base) {
|
|
nfsd_reply_cache_free(b, rp, nn);
|
|
return;
|
|
}
|
|
cachv->iov_len = bufsize;
|
|
memcpy(cachv->iov_base, statp, bufsize);
|
|
break;
|
|
case RC_NOCACHE:
|
|
nfsd_reply_cache_free(b, rp, nn);
|
|
return;
|
|
}
|
|
spin_lock(&b->cache_lock);
|
|
nfsd_stats_drc_mem_usage_add(nn, bufsize);
|
|
lru_put_end(b, rp);
|
|
rp->c_secure = test_bit(RQ_SECURE, &rqstp->rq_flags);
|
|
rp->c_type = cachetype;
|
|
rp->c_state = RC_DONE;
|
|
spin_unlock(&b->cache_lock);
|
|
return;
|
|
}
|
|
|
|
static int
|
|
nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *data)
|
|
{
|
|
__be32 *p;
|
|
|
|
p = xdr_reserve_space(&rqstp->rq_res_stream, data->iov_len);
|
|
if (unlikely(!p))
|
|
return false;
|
|
memcpy(p, data->iov_base, data->iov_len);
|
|
xdr_commit_encode(&rqstp->rq_res_stream);
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
int nfsd_reply_cache_stats_show(struct seq_file *m, void *v)
|
|
{
|
|
struct nfsd_net *nn = net_generic(file_inode(m->file)->i_sb->s_fs_info,
|
|
nfsd_net_id);
|
|
|
|
seq_printf(m, "max entries: %u\n", nn->max_drc_entries);
|
|
seq_printf(m, "num entries: %u\n",
|
|
atomic_read(&nn->num_drc_entries));
|
|
seq_printf(m, "hash buckets: %u\n", 1 << nn->maskbits);
|
|
seq_printf(m, "mem usage: %lld\n",
|
|
percpu_counter_sum_positive(&nn->counter[NFSD_STATS_DRC_MEM_USAGE]));
|
|
seq_printf(m, "cache hits: %lld\n",
|
|
percpu_counter_sum_positive(&nn->counter[NFSD_STATS_RC_HITS]));
|
|
seq_printf(m, "cache misses: %lld\n",
|
|
percpu_counter_sum_positive(&nn->counter[NFSD_STATS_RC_MISSES]));
|
|
seq_printf(m, "not cached: %lld\n",
|
|
percpu_counter_sum_positive(&nn->counter[NFSD_STATS_RC_NOCACHE]));
|
|
seq_printf(m, "payload misses: %lld\n",
|
|
percpu_counter_sum_positive(&nn->counter[NFSD_STATS_PAYLOAD_MISSES]));
|
|
seq_printf(m, "longest chain len: %u\n", nn->longest_chain);
|
|
seq_printf(m, "cachesize at longest: %u\n", nn->longest_chain_cachesize);
|
|
return 0;
|
|
}
|