LU-13970 llite: add option to disable Lustre inode cache

A tunable option is added to disable Lustre inode cache:
"llite.*.inode_cache=0" (default =1)

When it's turned off, ll_drop_inode() always returns 1, then
the last iput() will release inode.

Add sanity test_433.

Signed-off-by: Lai Siyao <lai.siyao@whamcloud.com>
Change-Id: I0642bdc694dc365a05395c3fae98131e1e7723c6
Reviewed-on: https://review.whamcloud.com/39973
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Olaf Faaland-LLNL <faaland1@llnl.gov>

diff --git a/lustre/llite/llite_internal.h b/lustre/llite/llite_internal.h
index 1318639..796a4a8 100644 (file)
--- a/lustre/llite/llite_internal.h
+++ b/lustre/llite/llite_internal.h
@@ -691,7 +691,8 @@ struct ll_sb_info {
        unsigned int             ll_xattr_cache_enabled:1,
                                 ll_xattr_cache_set:1, /* already set to 0/1 */
                                 ll_client_common_fill_super_succeeded:1,
-                                ll_checksum_set:1;
+                                ll_checksum_set:1,
+                                ll_inode_cache_enabled:1;
 
        struct lustre_client_ocd ll_lco;
 

diff --git a/lustre/llite/llite_lib.c b/lustre/llite/llite_lib.c
index 2456745..ff70403 100644 (file)
--- a/lustre/llite/llite_lib.c
+++ b/lustre/llite/llite_lib.c
@@ -452,6 +452,7 @@ static int client_common_fill_super(struct super_block *sb, char *md, char *dt)
        sb->s_blocksize_bits = log2(osfs->os_bsize);
        sb->s_magic = LL_SUPER_MAGIC;
        sb->s_maxbytes = MAX_LFS_FILESIZE;
+       sbi->ll_inode_cache_enabled = 1;
        sbi->ll_namelen = osfs->os_namelen;
        sbi->ll_mnt.mnt = current->fs->root.mnt;
        sbi->ll_mnt_ns = current->nsproxy->mnt_ns;

diff --git a/lustre/llite/lproc_llite.c b/lustre/llite/lproc_llite.c
index 8e972c7..abe3b93 100644 (file)
--- a/lustre/llite/lproc_llite.c
+++ b/lustre/llite/lproc_llite.c
@@ -1472,6 +1472,36 @@ static ssize_t opencache_max_ms_store(struct kobject *kobj,
 }
 LUSTRE_RW_ATTR(opencache_max_ms);
 
+static ssize_t inode_cache_show(struct kobject *kobj,
+                               struct attribute *attr,
+                               char *buf)
+{
+       struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
+                                             ll_kset.kobj);
+
+       return snprintf(buf, PAGE_SIZE, "%u\n", sbi->ll_inode_cache_enabled);
+}
+
+static ssize_t inode_cache_store(struct kobject *kobj,
+                                struct attribute *attr,
+                                const char *buffer,
+                                size_t count)
+{
+       struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
+                                             ll_kset.kobj);
+       bool val;
+       int rc;
+
+       rc = kstrtobool(buffer, &val);
+       if (rc)
+               return rc;
+
+       sbi->ll_inode_cache_enabled = val;
+
+       return count;
+}
+LUSTRE_RW_ATTR(inode_cache);
+
 static int ll_unstable_stats_seq_show(struct seq_file *m, void *v)
 {
        struct super_block      *sb    = m->private;
@@ -1728,6 +1758,7 @@ static struct attribute *llite_attrs[] = {
        &lustre_attr_opencache_threshold_count.attr,
        &lustre_attr_opencache_threshold_ms.attr,
        &lustre_attr_opencache_max_ms.attr,
+       &lustre_attr_inode_cache.attr,
        NULL,
 };
 

diff --git a/lustre/llite/super25.c b/lustre/llite/super25.c
index bf4d3ea..1cd850e 100644 (file)
--- a/lustre/llite/super25.c
+++ b/lustre/llite/super25.c
@@ -73,8 +73,13 @@ static void ll_destroy_inode(struct inode *inode)
 
 static int ll_drop_inode(struct inode *inode)
 {
-       int drop = generic_drop_inode(inode);
+       struct ll_sb_info *sbi = ll_i2sbi(inode);
+       int drop;
 
+       if (!sbi->ll_inode_cache_enabled)
+               return 1;
+
+       drop = generic_drop_inode(inode);
        if (!drop)
                drop = llcrypt_drop_inode(inode);
 

diff --git a/lustre/tests/sanity.sh b/lustre/tests/sanity.sh
index 9a8de64..7130179 100755 (executable)
--- a/lustre/tests/sanity.sh
+++ b/lustre/tests/sanity.sh
@@ -26859,6 +26859,45 @@ test_432() {
 }
 run_test 432 "mv dir from outside Lustre"
 
+test_433() {
+       [ $PARALLEL == "yes" ] && skip "skip parallel run"
+
+       [[ -n "$($LCTL list_param llite.*.inode_cache 2>/dev/null)" ]] ||
+               skip "inode cache not supported"
+
+       $LCTL set_param llite.*.inode_cache=0
+       stack_trap "$LCTL set_param llite.*.inode_cache=1"
+
+       local count=256
+       local before
+       local after
+
+       cancel_lru_locks mdc
+       test_mkdir $DIR/$tdir || error "mkdir $tdir"
+       createmany -m $DIR/$tdir/f $count
+       createmany -d $DIR/$tdir/d $count
+       ls -l $DIR/$tdir > /dev/null
+       stack_trap "rm -rf $DIR/$tdir"
+
+       before=$(num_objects)
+       cancel_lru_locks mdc
+       after=$(num_objects)
+
+       # sometimes even @before is less than 2 * count
+       while (( before - after < count )); do
+               sleep 1
+               after=$(num_objects)
+               wait=$((wait + 1))
+               (( wait % 5 == 0 )) && echo "wait $wait seconds objects: $after"
+               if (( wait > 60 )); then
+                       error "inode slab grew from $before to $after"
+               fi
+       done
+
+       echo "lustre_inode_cache $before objs before lock cancel, $after after"
+}
+run_test 433 "ldlm lock cancel releases dentries and inodes"
+
 prep_801() {
        [[ $MDS1_VERSION -lt $(version_code 2.9.55) ]] ||
        [[ $OST1_VERSION -lt $(version_code 2.9.55) ]] &&