[PATCH 3/5] staging: zcache: replace xvmalloc with zsmalloc

From: Seth Jennings
Date: Mon Jan 09 2012 - 17:52:47 EST


Replaces xvmalloc with zsmalloc as the persistent memory allocator
for zcache

Signed-off-by: Seth Jennings <sjenning@xxxxxxxxxxxxxxxxxx>
---
drivers/staging/zcache/Kconfig | 2 +-
drivers/staging/zcache/zcache-main.c | 83 +++++++++++++++++----------------
2 files changed, 44 insertions(+), 41 deletions(-)

diff --git a/drivers/staging/zcache/Kconfig b/drivers/staging/zcache/Kconfig
index 1b7bba7..94e48aa 100644
--- a/drivers/staging/zcache/Kconfig
+++ b/drivers/staging/zcache/Kconfig
@@ -1,7 +1,7 @@
config ZCACHE
tristate "Dynamic compression of swap pages and clean pagecache pages"
depends on (CLEANCACHE || FRONTSWAP) && CRYPTO
- select XVMALLOC
+ select ZSMALLOC
select CRYPTO_LZO
default n
help
diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c
index 2faa9a7..bcc8440 100644
--- a/drivers/staging/zcache/zcache-main.c
+++ b/drivers/staging/zcache/zcache-main.c
@@ -9,7 +9,7 @@
* page-accessible memory [1] interfaces, both utilizing the crypto compression
* API:
* 1) "compression buddies" ("zbud") is used for ephemeral pages
- * 2) xvmalloc is used for persistent pages.
+ * 2) zsmalloc is used for persistent pages.
* Xvmalloc (based on the TLSF allocator) has very low fragmentation
* so maximizes space efficiency, while zbud allows pairs (and potentially,
* in the future, more than a pair of) compressed pages to be closely linked
@@ -33,7 +33,7 @@
#include <linux/string.h>
#include "tmem.h"

-#include "../zram/xvmalloc.h" /* if built in drivers/staging */
+#include "../zsmalloc/zsmalloc.h"

#if (!defined(CONFIG_CLEANCACHE) && !defined(CONFIG_FRONTSWAP))
#error "zcache is useless without CONFIG_CLEANCACHE or CONFIG_FRONTSWAP"
@@ -62,7 +62,7 @@ MODULE_LICENSE("GPL");

struct zcache_client {
struct tmem_pool *tmem_pools[MAX_POOLS_PER_CLIENT];
- struct xv_pool *xvpool;
+ struct zs_pool *zspool;
bool allocated;
atomic_t refcount;
};
@@ -658,7 +658,7 @@ static int zbud_show_cumul_chunk_counts(char *buf)
#endif

/**********
- * This "zv" PAM implementation combines the TLSF-based xvMalloc
+ * This "zv" PAM implementation combines the slab-based zsmalloc
* with the crypto compression API to maximize the amount of data that can
* be packed into a physical page.
*
@@ -672,6 +672,7 @@ struct zv_hdr {
uint32_t pool_id;
struct tmem_oid oid;
uint32_t index;
+ size_t size;
DECL_SENTINEL
};

@@ -693,71 +694,73 @@ static unsigned int zv_max_mean_zsize = (PAGE_SIZE / 8) * 5;
static atomic_t zv_curr_dist_counts[NCHUNKS];
static atomic_t zv_cumul_dist_counts[NCHUNKS];

-static struct zv_hdr *zv_create(struct xv_pool *xvpool, uint32_t pool_id,
+static struct zv_hdr *zv_create(struct zs_pool *pool, uint32_t pool_id,
struct tmem_oid *oid, uint32_t index,
void *cdata, unsigned clen)
{
- struct page *page;
- struct zv_hdr *zv = NULL;
- uint32_t offset;
- int alloc_size = clen + sizeof(struct zv_hdr);
- int chunks = (alloc_size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT;
- int ret;
+ struct zv_hdr *zv;
+ u32 size = clen + sizeof(struct zv_hdr);
+ int chunks = (size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT;
+ void *handle = NULL;
+ char *buf;

BUG_ON(!irqs_disabled());
BUG_ON(chunks >= NCHUNKS);
- ret = xv_malloc(xvpool, alloc_size,
- &page, &offset, ZCACHE_GFP_MASK);
- if (unlikely(ret))
+ handle = zs_malloc(pool, size);
+ if (!handle)
goto out;
atomic_inc(&zv_curr_dist_counts[chunks]);
atomic_inc(&zv_cumul_dist_counts[chunks]);
- zv = kmap_atomic(page, KM_USER0) + offset;
+ zv = (struct zv_hdr *)((char *)cdata - sizeof(*zv));
zv->index = index;
zv->oid = *oid;
zv->pool_id = pool_id;
+ zv->size = clen;
SET_SENTINEL(zv, ZVH);
- memcpy((char *)zv + sizeof(struct zv_hdr), cdata, clen);
- kunmap_atomic(zv, KM_USER0);
+ buf = zs_map_object(pool, handle);
+ memcpy(buf, zv, clen + sizeof(*zv));
+ zs_unmap_object(pool, handle);
out:
- return zv;
+ return handle;
}

-static void zv_free(struct xv_pool *xvpool, struct zv_hdr *zv)
+static void zv_free(struct zs_pool *pool, void *handle)
{
unsigned long flags;
- struct page *page;
- uint32_t offset;
- uint16_t size = xv_get_object_size(zv);
- int chunks = (size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT;
+ struct zv_hdr *zv;
+ uint16_t size;
+ int chunks;

+ zv = zs_map_object(pool, handle);
ASSERT_SENTINEL(zv, ZVH);
+ size = zv->size + sizeof(struct zv_hdr);
+ INVERT_SENTINEL(zv, ZVH);
+ zs_unmap_object(pool, handle);
+
+ chunks = (size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT;
BUG_ON(chunks >= NCHUNKS);
atomic_dec(&zv_curr_dist_counts[chunks]);
- size -= sizeof(*zv);
- BUG_ON(size == 0);
- INVERT_SENTINEL(zv, ZVH);
- page = virt_to_page(zv);
- offset = (unsigned long)zv & ~PAGE_MASK;
+
local_irq_save(flags);
- xv_free(xvpool, page, offset);
+ zs_free(pool, handle);
local_irq_restore(flags);
}

-static void zv_decompress(struct page *page, struct zv_hdr *zv)
+static void zv_decompress(struct page *page, void *handle)
{
unsigned int clen = PAGE_SIZE;
char *to_va;
- unsigned size;
int ret;
+ struct zv_hdr *zv;

+ zv = zs_map_object(zcache_host.zspool, handle);
+ BUG_ON(zv->size == 0);
ASSERT_SENTINEL(zv, ZVH);
- size = xv_get_object_size(zv) - sizeof(*zv);
- BUG_ON(size == 0);
to_va = kmap_atomic(page, KM_USER0);
ret = zcache_comp_op(ZCACHE_COMPOP_DECOMPRESS, (char *)zv + sizeof(*zv),
- size, to_va, &clen);
+ zv->size, to_va, &clen);
kunmap_atomic(to_va, KM_USER0);
+ zs_unmap_object(zcache_host.zspool, handle);
BUG_ON(ret);
BUG_ON(clen != PAGE_SIZE);
}
@@ -984,8 +987,8 @@ int zcache_new_client(uint16_t cli_id)
goto out;
cli->allocated = 1;
#ifdef CONFIG_FRONTSWAP
- cli->xvpool = xv_create_pool();
- if (cli->xvpool == NULL)
+ cli->zspool = zs_create_pool("zcache", ZCACHE_GFP_MASK);
+ if (cli->zspool == NULL)
goto out;
#endif
ret = 0;
@@ -1216,7 +1219,7 @@ static void *zcache_pampd_create(char *data, size_t size, bool raw, int eph,
}
/* reject if mean compression is too poor */
if ((clen > zv_max_mean_zsize) && (curr_pers_pampd_count > 0)) {
- total_zsize = xv_get_total_size_bytes(cli->xvpool);
+ total_zsize = zs_get_total_size_bytes(cli->zspool);
zv_mean_zsize = div_u64(total_zsize,
curr_pers_pampd_count);
if (zv_mean_zsize > zv_max_mean_zsize) {
@@ -1224,7 +1227,7 @@ static void *zcache_pampd_create(char *data, size_t size, bool raw, int eph,
goto out;
}
}
- pampd = (void *)zv_create(cli->xvpool, pool->pool_id,
+ pampd = (void *)zv_create(cli->zspool, pool->pool_id,
oid, index, cdata, clen);
if (pampd == NULL)
goto out;
@@ -1282,7 +1285,7 @@ static void zcache_pampd_free(void *pampd, struct tmem_pool *pool,
atomic_dec(&zcache_curr_eph_pampd_count);
BUG_ON(atomic_read(&zcache_curr_eph_pampd_count) < 0);
} else {
- zv_free(cli->xvpool, (struct zv_hdr *)pampd);
+ zv_free(cli->zspool, pampd);
atomic_dec(&zcache_curr_pers_pampd_count);
BUG_ON(atomic_read(&zcache_curr_pers_pampd_count) < 0);
}
@@ -2072,7 +2075,7 @@ static int __init zcache_init(void)

old_ops = zcache_frontswap_register_ops();
pr_info("zcache: frontswap enabled using kernel "
- "transcendent memory and xvmalloc\n");
+ "transcendent memory and zsmalloc\n");
if (old_ops.init != NULL)
pr_warning("zcache: frontswap_ops overridden");
}
--
1.7.5.4

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