[PATCH 3/5] staging/lustre/ptlrpc: convert to new shrinker API

From: Peng Tao
Date: Fri Jun 07 2013 - 08:56:48 EST


Convert sptlrpc encode pool shrinker to use scan/count API.

Cc: Dave Chinner <dchinner@xxxxxxxxxx>
Signed-off-by: Peng Tao <tao.peng@xxxxxxx>
Signed-off-by: Andreas Dilger <andreas.dilger@xxxxxxxxx>
---
drivers/staging/lustre/lustre/ptlrpc/sec_bulk.c | 76 +++++++++++++----------
1 file changed, 42 insertions(+), 34 deletions(-)

diff --git a/drivers/staging/lustre/lustre/ptlrpc/sec_bulk.c b/drivers/staging/lustre/lustre/ptlrpc/sec_bulk.c
index bf53f1b..87eea53 100644
--- a/drivers/staging/lustre/lustre/ptlrpc/sec_bulk.c
+++ b/drivers/staging/lustre/lustre/ptlrpc/sec_bulk.c
@@ -121,13 +121,6 @@ static struct ptlrpc_enc_page_pool {
} page_pools;

/*
- * memory shrinker
- */
-const int pools_shrinker_seeks = DEFAULT_SEEKS;
-static struct shrinker *pools_shrinker = NULL;
-
-
-/*
* /proc/fs/lustre/sptlrpc/encrypt_page_pools
*/
int sptlrpc_proc_enc_pool_seq_show(struct seq_file *m, void *v)
@@ -226,30 +219,46 @@ static void enc_pools_release_free_pages(long npages)
}

/*
- * could be called frequently for query (@nr_to_scan == 0).
* we try to keep at least PTLRPC_MAX_BRW_PAGES pages in the pool.
*/
-static int enc_pools_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask))
+static unsigned long enc_pools_shrink_count(struct shrinker *s,
+ struct shrink_control *sc)
{
- if (unlikely(shrink_param(sc, nr_to_scan) != 0)) {
+ /*
+ * if no pool access for a long time, we consider it's fully idle.
+ * a little race here is fine.
+ */
+ if (unlikely(cfs_time_current_sec() - page_pools.epp_last_access >
+ CACHE_QUIESCENT_PERIOD)) {
spin_lock(&page_pools.epp_lock);
- shrink_param(sc, nr_to_scan) = min_t(unsigned long,
- shrink_param(sc, nr_to_scan),
- page_pools.epp_free_pages -
- PTLRPC_MAX_BRW_PAGES);
- if (shrink_param(sc, nr_to_scan) > 0) {
- enc_pools_release_free_pages(shrink_param(sc,
- nr_to_scan));
- CDEBUG(D_SEC, "released %ld pages, %ld left\n",
- (long)shrink_param(sc, nr_to_scan),
- page_pools.epp_free_pages);
-
- page_pools.epp_st_shrinks++;
- page_pools.epp_last_shrink = cfs_time_current_sec();
- }
+ page_pools.epp_idle_idx = IDLE_IDX_MAX;
spin_unlock(&page_pools.epp_lock);
}

+ LASSERT(page_pools.epp_idle_idx <= IDLE_IDX_MAX);
+ return max((int)page_pools.epp_free_pages - PTLRPC_MAX_BRW_PAGES, 0) *
+ (IDLE_IDX_MAX - page_pools.epp_idle_idx) / IDLE_IDX_MAX;
+}
+
+/*
+ * we try to keep at least PTLRPC_MAX_BRW_PAGES pages in the pool.
+ */
+static unsigned long enc_pools_shrink_scan(struct shrinker *s,
+ struct shrink_control *sc)
+{
+ spin_lock(&page_pools.epp_lock);
+ sc->nr_to_scan = min_t(unsigned long, sc->nr_to_scan,
+ page_pools.epp_free_pages - PTLRPC_MAX_BRW_PAGES);
+ if (sc->nr_to_scan > 0) {
+ enc_pools_release_free_pages(sc->nr_to_scan);
+ CDEBUG(D_SEC, "released %ld pages, %ld left\n",
+ (long)sc->nr_to_scan, page_pools.epp_free_pages);
+
+ page_pools.epp_st_shrinks++;
+ page_pools.epp_last_shrink = cfs_time_current_sec();
+ }
+ spin_unlock(&page_pools.epp_lock);
+
/*
* if no pool access for a long time, we consider it's fully idle.
* a little race here is fine.
@@ -262,8 +271,7 @@ static int enc_pools_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask))
}

LASSERT(page_pools.epp_idle_idx <= IDLE_IDX_MAX);
- return max((int)page_pools.epp_free_pages - PTLRPC_MAX_BRW_PAGES, 0) *
- (IDLE_IDX_MAX - page_pools.epp_idle_idx) / IDLE_IDX_MAX;
+ return sc->nr_to_scan;
}

static inline
@@ -699,6 +707,12 @@ static inline void enc_pools_free(void)
sizeof(*page_pools.epp_pools));
}

+static struct shrinker pools_shrinker = {
+ .count_objects = enc_pools_shrink_count,
+ .scan_objects = enc_pools_shrink_scan,
+ .seeks = DEFAULT_SEEKS,
+};
+
int sptlrpc_enc_pool_init(void)
{
/*
@@ -736,12 +750,7 @@ int sptlrpc_enc_pool_init(void)
if (page_pools.epp_pools == NULL)
return -ENOMEM;

- pools_shrinker = set_shrinker(pools_shrinker_seeks,
- enc_pools_shrink);
- if (pools_shrinker == NULL) {
- enc_pools_free();
- return -ENOMEM;
- }
+ register_shrinker(&pools_shrinker);

return 0;
}
@@ -750,11 +759,10 @@ void sptlrpc_enc_pool_fini(void)
{
unsigned long cleaned, npools;

- LASSERT(pools_shrinker);
LASSERT(page_pools.epp_pools);
LASSERT(page_pools.epp_total_pages == page_pools.epp_free_pages);

- remove_shrinker(pools_shrinker);
+ unregister_shrinker(&pools_shrinker);

npools = npages_to_npools(page_pools.epp_total_pages);
cleaned = enc_pools_cleanup(page_pools.epp_pools, npools);
--
1.7.9.5

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