[PATCH 2/5] mm: add context argument to shrinker callback

Dave Chinner
2010-05-14T07:25:23Z

From: Dave Chinner <dchinner@redhat.com>

The current shrinker implementation requires the registered callback
to have global state to work from. This makes it difficult to shrink
caches that are not global (e.g. per-filesystem caches). Pass the shrinker
structure to the callback so that users can embed the shrinker structure
in the context the shrinker needs to operate on and get back to it in the
callback via container_of().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
arch/x86/kvm/mmu.c | 2 +-
drivers/gpu/drm/i915/i915_gem.c | 2 +-
fs/dcache.c | 2 +-
fs/gfs2/glock.c | 2 +-
fs/gfs2/quota.c | 2 +-
fs/gfs2/quota.h | 2 +-
fs/inode.c | 2 +-
fs/mbcache.c | 5 +++--
fs/nfs/dir.c | 2 +-
fs/nfs/internal.h | 3 ++-
fs/quota/dquot.c | 2 +-
fs/ubifs/shrinker.c | 2 +-
fs/ubifs/ubifs.h | 2 +-
fs/xfs/linux-2.6/xfs_buf.c | 5 +++--
fs/xfs/linux-2.6/xfs_sync.c | 1 +
fs/xfs/quota/xfs_qm.c | 7 +++++--
include/linux/mm.h | 2 +-
mm/vmscan.c | 8 +++++---
18 files changed, 31 insertions(+), 22 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 19a8906..03e689d 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2918,7 +2918,7 @@ static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm *kvm)
kvm_mmu_zap_page(kvm, page);
}

-static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask)
+static int mmu_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
{
struct kvm *kvm;
struct kvm *kvm_freed = NULL;
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index ef3d91d..cc436ba 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -5185,7 +5185,7 @@ void i915_gem_release(struct drm_device * dev, struct drm_file *file_priv)
}

static int
-i915_gem_shrink(int nr_to_scan, gfp_t gfp_mask)
+i915_gem_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
{
drm_i915_private_t *dev_priv, *next_dev;
struct drm_i915_gem_object *obj_priv, *next_obj;
diff --git a/fs/dcache.c b/fs/dcache.c
index f1358e5..41c35c1 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -897,7 +897,7 @@ EXPORT_SYMBOL(shrink_dcache_parent);
*
* In this case we return -1 to tell the caller that we baled.
*/
-static int shrink_dcache_memory(int nr, gfp_t gfp_mask)
+static int shrink_dcache_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
{
if (nr) {
if (!(gfp_mask & __GFP_FS))
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 454d4b4..e947661 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1345,7 +1345,7 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
}

-static int gfs2_shrink_glock_memory(int nr, gfp_t gfp_mask)
+static int gfs2_shrink_glock_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
{
struct gfs2_glock *gl;
int may_demote;
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 6dbcbad..3f2cf67 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -77,7 +77,7 @@ static LIST_HEAD(qd_lru_list);
static atomic_t qd_lru_count = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(qd_lru_lock);

-int gfs2_shrink_qd_memory(int nr, gfp_t gfp_mask)
+int gfs2_shrink_qd_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
{
struct gfs2_quota_data *qd;
struct gfs2_sbd *sdp;
diff --git a/fs/gfs2/quota.h b/fs/gfs2/quota.h
index 195f60c..e7d236c 100644
--- a/fs/gfs2/quota.h
+++ b/fs/gfs2/quota.h
@@ -51,7 +51,7 @@ static inline int gfs2_quota_lock_check(struct gfs2_inode *ip)
return ret;
}

-extern int gfs2_shrink_qd_memory(int nr, gfp_t gfp_mask);
+extern int gfs2_shrink_qd_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask);
extern const struct quotactl_ops gfs2_quotactl_ops;

#endif /* __QUOTA_DOT_H__ */
diff --git a/fs/inode.c b/fs/inode.c
index 8b95b15..b292e41 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -581,7 +581,7 @@ restart:
* This function is passed the number of inodes to scan, and it returns the
* total number of remaining possibly-reclaimable inodes.
*/
-static int shrink_icache_memory(int nr, gfp_t gfp_mask)
+static int shrink_icache_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
{
if (nr) {
/*
diff --git a/fs/mbcache.c b/fs/mbcache.c
index ec88ff3..e28f21b 100644
--- a/fs/mbcache.c
+++ b/fs/mbcache.c
@@ -115,7 +115,7 @@ mb_cache_indexes(struct mb_cache *cache)
* What the mbcache registers as to get shrunk dynamically.
*/

-static int mb_cache_shrink_fn(int nr_to_scan, gfp_t gfp_mask);
+static int mb_cache_shrink_fn(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask);

static struct shrinker mb_cache_shrinker = {
.shrink = mb_cache_shrink_fn,
@@ -191,13 +191,14 @@ forget:
* This function is called by the kernel memory management when memory
* gets low.
*
+ * @shrink: (ignored)
* @nr_to_scan: Number of objects to scan
* @gfp_mask: (ignored)
*
* Returns the number of objects which are present in the cache.
*/
static int
-mb_cache_shrink_fn(int nr_to_scan, gfp_t gfp_mask)
+mb_cache_shrink_fn(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
{
LIST_HEAD(free_list);
struct list_head *l, *ltmp;
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index a7bb5c6..6a0a6f7 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1669,7 +1669,7 @@ static void nfs_access_free_entry(struct nfs_access_entry *entry)
smp_mb__after_atomic_dec();
}

-int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask)
+int nfs_access_cache_shrinker(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
{
LIST_HEAD(head);
struct nfs_inode *nfsi;
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 11f82f0..aa022eb 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -205,7 +205,8 @@ extern struct rpc_procinfo nfs4_procedures[];
void nfs_close_context(struct nfs_open_context *ctx, int is_sync);

/* dir.c */
-extern int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask);
+extern int nfs_access_cache_shrinker(struct shrinker *shrink,
+ int nr_to_scan, gfp_t gfp_mask);

/* inode.c */
extern struct workqueue_struct *nfsiod_workqueue;
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 788b580..187e3f2 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -668,7 +668,7 @@ static void prune_dqcache(int count)
* more memory
*/

-static int shrink_dqcache_memory(int nr, gfp_t gfp_mask)
+static int shrink_dqcache_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
{
if (nr) {
spin_lock(&dq_list_lock);
diff --git a/fs/ubifs/shrinker.c b/fs/ubifs/shrinker.c
index 02feb59..0b20111 100644
--- a/fs/ubifs/shrinker.c
+++ b/fs/ubifs/shrinker.c
@@ -277,7 +277,7 @@ static int kick_a_thread(void)
return 0;
}

-int ubifs_shrinker(int nr, gfp_t gfp_mask)
+int ubifs_shrinker(struct shrinker *shrink, int nr, gfp_t gfp_mask)
{
int freed, contention = 0;
long clean_zn_cnt = atomic_long_read(&ubifs_clean_zn_cnt);
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index bd2542d..5a92345 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1575,7 +1575,7 @@ int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot);
int ubifs_tnc_end_commit(struct ubifs_info *c);

/* shrinker.c */
-int ubifs_shrinker(int nr_to_scan, gfp_t gfp_mask);
+int ubifs_shrinker(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask);

/* commit.c */
int ubifs_bg_thread(void *info);
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 44c2b0e..d2cfc54 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -44,7 +44,7 @@

static kmem_zone_t *xfs_buf_zone;
STATIC int xfsbufd(void *);
-STATIC int xfsbufd_wakeup(int, gfp_t);
+STATIC int xfsbufd_wakeup(struct shrinker *, int, gfp_t);
STATIC void xfs_buf_delwri_queue(xfs_buf_t *, int);
static struct shrinker xfs_buf_shake = {
.shrink = xfsbufd_wakeup,
@@ -339,7 +339,7 @@ _xfs_buf_lookup_pages(
__func__, gfp_mask);

XFS_STATS_INC(xb_page_retries);
- xfsbufd_wakeup(0, gfp_mask);
+ xfsbufd_wakeup(NULL, 0, gfp_mask);
congestion_wait(BLK_RW_ASYNC, HZ/50);
goto retry;
}
@@ -1756,6 +1756,7 @@ xfs_buf_runall_queues(

STATIC int
xfsbufd_wakeup(
+ struct shrinker *shrink,
int priority,
gfp_t mask)
{
diff --git a/fs/xfs/linux-2.6/xfs_sync.c b/fs/xfs/linux-2.6/xfs_sync.c
index a427c63..17ec4a6 100644
--- a/fs/xfs/linux-2.6/xfs_sync.c
+++ b/fs/xfs/linux-2.6/xfs_sync.c
@@ -879,6 +879,7 @@ static struct rw_semaphore xfs_mount_list_lock;

static int
xfs_reclaim_inode_shrink(
+ struct shrinker *shrink,
int nr_to_scan,
gfp_t gfp_mask)
{
diff --git a/fs/xfs/quota/xfs_qm.c b/fs/xfs/quota/xfs_qm.c
index 417e61e..49c8d84 100644
--- a/fs/xfs/quota/xfs_qm.c
+++ b/fs/xfs/quota/xfs_qm.c
@@ -72,7 +72,7 @@ STATIC void xfs_qm_freelist_destroy(xfs_frlist_t *);

STATIC int xfs_qm_init_quotainos(xfs_mount_t *);
STATIC int xfs_qm_init_quotainfo(xfs_mount_t *);
-STATIC int xfs_qm_shake(int, gfp_t);
+STATIC int xfs_qm_shake(struct shrinker *, int, gfp_t);

static struct shrinker xfs_qm_shaker = {
.shrink = xfs_qm_shake,
@@ -2088,7 +2088,10 @@ xfs_qm_shake_freelist(
*/
/* ARGSUSED */
STATIC int
-xfs_qm_shake(int nr_to_scan, gfp_t gfp_mask)
+xfs_qm_shake(
+ struct shrinker *shrink,
+ int nr_to_scan,
+ gfp_t gfp_mask)
{
int ndqused, nfree, n;

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 462acaf..ff4c44e 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -995,7 +995,7 @@ static inline void sync_mm_rss(struct task_struct *task, struct mm_struct *mm)
* querying the cache size, so a fastpath for that case is appropriate.
*/
struct shrinker {
- int (*shrink)(int nr_to_scan, gfp_t gfp_mask);
+ int (*shrink)(struct shrinker *, int nr_to_scan, gfp_t gfp_mask);
int seeks; /* seeks to recreate an obj */

/* These are for internal use */
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 3ff3311..9d56aaf 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -215,8 +215,9 @@ unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask,
list_for_each_entry(shrinker, &shrinker_list, list) {
unsigned long long delta;
unsigned long total_scan;
- unsigned long max_pass = (*shrinker->shrink)(0, gfp_mask);
+ unsigned long max_pass;

+ max_pass = (*shrinker->shrink)(shrinker, 0, gfp_mask);
delta = (4 * scanned) / shrinker->seeks;
delta *= max_pass;
do_div(delta, lru_pages + 1);
@@ -244,8 +245,9 @@ unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask,
int shrink_ret;
int nr_before;

- nr_before = (*shrinker->shrink)(0, gfp_mask);
- shrink_ret = (*shrinker->shrink)(this_scan, gfp_mask);
+ nr_before = (*shrinker->shrink)(shrinker, 0, gfp_mask);
+ shrink_ret = (*shrinker->shrink)(shrinker, this_scan,
+ gfp_mask);
if (shrink_ret == -1)
break;
if (shrink_ret < nr_before)
--
1.5.6.5