Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1b02bde3 authored by Emoly Liu's avatar Emoly Liu Committed by Greg Kroah-Hartman
Browse files

staging/lustre/llite: allocate and free client cache asynchronously 



Since the inflight request holds import refcount as well as export,
sometimes obd_disconnect() in client_common_put_super() can't put
the last refcount of OSC import (e.g. due to network disconnection),
this will cause cl_cache being accessed after free.

To fix this issue, ccc_users is used as cl_cache refcount, and
lov/llite/osc all hold one cl_cache refcount respectively, to avoid
the race that a new OST is being added into the system when the client
is mounted.
The following cl_cache functions are added:
- cl_cache_init(): allocate and initialize cl_cache
- cl_cache_incref(): increase cl_cache refcount
- cl_cache_decref(): decrease cl_cache refcount and free the cache
  if refcount=0.

Signed-off-by: default avatarEmoly Liu <emoly.liu@intel.com>
Reviewed-on: http://review.whamcloud.com/13746
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6173


Reviewed-by: default avatarNiu Yawei <yawei.niu@intel.com>
Signed-off-by: default avatarOleg Drokin <green@linuxhacker.ru>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 341f1f0a

drivers/staging/lustre/lustre/include/cl_object.h

+9 −1
Original line number Diff line number Diff line
@@ -2322,7 +2322,8 @@ void cl_lock_descr_print(const struct lu_env *env, void *cookie, 
 */

struct cl_client_cache {

	/**

	 * # of users (OSCs)

	 * # of client cache refcount

	 * # of users (OSCs) + 2 (held by llite and lov)

	 */

	atomic_t		ccc_users;

	/**
@@ -2357,6 +2358,13 @@ struct cl_client_cache { 


};



/**

 * cl_cache functions

 */

struct cl_client_cache *cl_cache_init(unsigned long lru_page_max);

void cl_cache_incref(struct cl_client_cache *cache);

void cl_cache_decref(struct cl_client_cache *cache);



/** @} cl_page */



/** \defgroup cl_lock cl_lock

drivers/staging/lustre/lustre/include/obd.h

+1 −1
Original line number Diff line number Diff line
@@ -415,7 +415,7 @@ struct lov_obd { 
	enum lustre_sec_part    lov_sp_me;



	/* Cached LRU and unstable data from upper layer */

	void		       *lov_cache;

	struct cl_client_cache *lov_cache;



	struct rw_semaphore     lov_notify_lock;

drivers/staging/lustre/lustre/llite/llite_internal.h

+1 −1
Original line number Diff line number Diff line
@@ -452,7 +452,7 @@ struct ll_sb_info { 
	 * any page which is sent to a server as part of a bulk request,

	 * but is uncommitted to stable storage.

	 */

	struct cl_client_cache    ll_cache;

	struct cl_client_cache    *ll_cache;



	struct lprocfs_stats     *ll_ra_stats;

drivers/staging/lustre/lustre/llite/llite_lib.c

+15 −20
Original line number Diff line number Diff line
@@ -83,15 +83,11 @@ static struct ll_sb_info *ll_init_sbi(struct super_block *sb) 
	pages = si.totalram - si.totalhigh;

	lru_page_max = pages / 2;



	/* initialize ll_cache data */

	atomic_set(&sbi->ll_cache.ccc_users, 0);

	sbi->ll_cache.ccc_lru_max = lru_page_max;

	atomic_set(&sbi->ll_cache.ccc_lru_left, lru_page_max);

	spin_lock_init(&sbi->ll_cache.ccc_lru_lock);

	INIT_LIST_HEAD(&sbi->ll_cache.ccc_lru);



	atomic_set(&sbi->ll_cache.ccc_unstable_nr, 0);

	init_waitqueue_head(&sbi->ll_cache.ccc_unstable_waitq);

	sbi->ll_cache = cl_cache_init(lru_page_max);

	if (!sbi->ll_cache) {

		kfree(sbi);

		return NULL;

	}



	sbi->ll_ra_info.ra_max_pages_per_file = min(pages / 32,

					   SBI_DEFAULT_READAHEAD_MAX);
@@ -131,6 +127,11 @@ static void ll_free_sbi(struct super_block *sb) 
{

	struct ll_sb_info *sbi = ll_s2sbi(sb);



	if (sbi->ll_cache) {

		cl_cache_decref(sbi->ll_cache);

		sbi->ll_cache = NULL;

	}



	kfree(sbi);

}
@@ -488,8 +489,8 @@ static int client_common_fill_super(struct super_block *sb, char *md, char *dt, 
	cl_sb_init(sb);



	err = obd_set_info_async(NULL, sbi->ll_dt_exp, sizeof(KEY_CACHE_SET),

				 KEY_CACHE_SET, sizeof(sbi->ll_cache),

				 &sbi->ll_cache, NULL);

				 KEY_CACHE_SET, sizeof(*sbi->ll_cache),

				 sbi->ll_cache, NULL);



	sb->s_root = d_make_root(root);

	if (!sb->s_root) {
@@ -534,8 +535,6 @@ static int client_common_fill_super(struct super_block *sb, char *md, char *dt, 
out_dt:

	obd_disconnect(sbi->ll_dt_exp);

	sbi->ll_dt_exp = NULL;

	/* Make sure all OScs are gone, since cl_cache is accessing sbi. */

	obd_zombie_barrier();

out_md_fid:

	obd_fid_fini(sbi->ll_md_exp->exp_obd);

out_md:
@@ -585,10 +584,6 @@ static void client_common_put_super(struct super_block *sb) 
	obd_fid_fini(sbi->ll_dt_exp->exp_obd);

	obd_disconnect(sbi->ll_dt_exp);

	sbi->ll_dt_exp = NULL;

	/* wait till all OSCs are gone, since cl_cache is accessing sbi.

	 * see LU-2543.

	 */

	obd_zombie_barrier();



	ldebugfs_unregister_mountpoint(sbi);
@@ -921,12 +916,12 @@ void ll_put_super(struct super_block *sb) 
	if (!force) {

		struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);



		rc = l_wait_event(sbi->ll_cache.ccc_unstable_waitq,

				  !atomic_read(&sbi->ll_cache.ccc_unstable_nr),

		rc = l_wait_event(sbi->ll_cache->ccc_unstable_waitq,

				  !atomic_read(&sbi->ll_cache->ccc_unstable_nr),

				  &lwi);

	}



	ccc_count = atomic_read(&sbi->ll_cache.ccc_unstable_nr);

	ccc_count = atomic_read(&sbi->ll_cache->ccc_unstable_nr);

	if (!force && rc != -EINTR)

		LASSERTF(!ccc_count, "count: %i\n", ccc_count);

drivers/staging/lustre/lustre/llite/lproc_llite.c

+3 −3
Original line number Diff line number Diff line
@@ -356,7 +356,7 @@ static int ll_max_cached_mb_seq_show(struct seq_file *m, void *v) 
{

	struct super_block     *sb    = m->private;

	struct ll_sb_info      *sbi   = ll_s2sbi(sb);

	struct cl_client_cache *cache = &sbi->ll_cache;

	struct cl_client_cache *cache = sbi->ll_cache;

	int shift = 20 - PAGE_SHIFT;

	int max_cached_mb;

	int unused_mb;
@@ -383,7 +383,7 @@ static ssize_t ll_max_cached_mb_seq_write(struct file *file, 
{

	struct super_block *sb = ((struct seq_file *)file->private_data)->private;

	struct ll_sb_info *sbi = ll_s2sbi(sb);

	struct cl_client_cache *cache = &sbi->ll_cache;

	struct cl_client_cache *cache = sbi->ll_cache;

	struct lu_env *env;

	int refcheck;

	int mult, rc, pages_number;
@@ -822,7 +822,7 @@ static ssize_t unstable_stats_show(struct kobject *kobj, 
{

	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,

					      ll_kobj);

	struct cl_client_cache *cache = &sbi->ll_cache;

	struct cl_client_cache *cache = sbi->ll_cache;

	int pages, mb;



	pages = atomic_read(&cache->ccc_unstable_nr);