[PATCH 5.15 197/731] nvmet: only allocate a single slab for bvecs

Greg Kroah-Hartman
2022-12-28T14:54:44Z

From: Christoph Hellwig <hch@lst.de>

[ Upstream commit fa8f9ac42350edd3ce82d0d148a60f0fa088f995 ]

There is no need to have a separate slab cache for each namespace,
and having separate ones creates duplicate debugs file names as well.

Fixes: d5eff33ee6f8 ("nvmet: add simple file backed ns support")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/nvme/target/core.c | 22 ++++++++++++++--------
drivers/nvme/target/io-cmd-file.c | 16 +++-------------
drivers/nvme/target/nvmet.h | 3 ++-
3 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 87a347248c38..cfd038551156 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -15,6 +15,7 @@

#include "nvmet.h"

+struct kmem_cache *nvmet_bvec_cache;
struct workqueue_struct *buffered_io_wq;
struct workqueue_struct *zbd_wq;
static const struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX];
@@ -1607,26 +1608,28 @@ void nvmet_subsys_put(struct nvmet_subsys *subsys)

static int __init nvmet_init(void)
{
- int error;
+ int error = -ENOMEM;

nvmet_ana_group_enabled[NVMET_DEFAULT_ANA_GRPID] = 1;

+ nvmet_bvec_cache = kmem_cache_create("nvmet-bvec",
+ NVMET_MAX_MPOOL_BVEC * sizeof(struct bio_vec), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!nvmet_bvec_cache)
+ return -ENOMEM;
+
zbd_wq = alloc_workqueue("nvmet-zbd-wq", WQ_MEM_RECLAIM, 0);
if (!zbd_wq)
- return -ENOMEM;
+ goto out_destroy_bvec_cache;

buffered_io_wq = alloc_workqueue("nvmet-buffered-io-wq",
WQ_MEM_RECLAIM, 0);
- if (!buffered_io_wq) {
- error = -ENOMEM;
+ if (!buffered_io_wq)
goto out_free_zbd_work_queue;
- }

nvmet_wq = alloc_workqueue("nvmet-wq", WQ_MEM_RECLAIM, 0);
- if (!nvmet_wq) {
- error = -ENOMEM;
+ if (!nvmet_wq)
goto out_free_buffered_work_queue;
- }

error = nvmet_init_discovery();
if (error)
@@ -1645,6 +1648,8 @@ static int __init nvmet_init(void)
destroy_workqueue(buffered_io_wq);
out_free_zbd_work_queue:
destroy_workqueue(zbd_wq);
+out_destroy_bvec_cache:
+ kmem_cache_destroy(nvmet_bvec_cache);
return error;
}

@@ -1656,6 +1661,7 @@ static void __exit nvmet_exit(void)
destroy_workqueue(nvmet_wq);
destroy_workqueue(buffered_io_wq);
destroy_workqueue(zbd_wq);
+ kmem_cache_destroy(nvmet_bvec_cache);

BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_entry) != 1024);
BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_hdr) != 1024);
diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index 228871d48106..eadba13b276d 100644
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -11,7 +11,6 @@
#include <linux/fs.h>
#include "nvmet.h"

-#define NVMET_MAX_MPOOL_BVEC 16
#define NVMET_MIN_MPOOL_OBJ 16

int nvmet_file_ns_revalidate(struct nvmet_ns *ns)
@@ -33,8 +32,6 @@ void nvmet_file_ns_disable(struct nvmet_ns *ns)
flush_workqueue(buffered_io_wq);
mempool_destroy(ns->bvec_pool);
ns->bvec_pool = NULL;
- kmem_cache_destroy(ns->bvec_cache);
- ns->bvec_cache = NULL;
fput(ns->file);
ns->file = NULL;
}
@@ -68,16 +65,8 @@ int nvmet_file_ns_enable(struct nvmet_ns *ns)
ns->blksize_shift = min_t(u8,
file_inode(ns->file)->i_blkbits, 12);

- ns->bvec_cache = kmem_cache_create("nvmet-bvec",
- NVMET_MAX_MPOOL_BVEC * sizeof(struct bio_vec),
- 0, SLAB_HWCACHE_ALIGN, NULL);
- if (!ns->bvec_cache) {
- ret = -ENOMEM;
- goto err;
- }
-
ns->bvec_pool = mempool_create(NVMET_MIN_MPOOL_OBJ, mempool_alloc_slab,
- mempool_free_slab, ns->bvec_cache);
+ mempool_free_slab, nvmet_bvec_cache);

if (!ns->bvec_pool) {
ret = -ENOMEM;
@@ -86,9 +75,10 @@ int nvmet_file_ns_enable(struct nvmet_ns *ns)

return ret;
err:
+ fput(ns->file);
+ ns->file = NULL;
ns->size = 0;
ns->blksize_shift = 0;
- nvmet_file_ns_disable(ns);
return ret;
}

diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index dbeb0b8c1194..fdb06a9d430d 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -77,7 +77,6 @@ struct nvmet_ns {

struct completion disable_done;
mempool_t *bvec_pool;
- struct kmem_cache *bvec_cache;

int use_p2pmem;
struct pci_dev *p2p_dev;
@@ -363,6 +362,8 @@ struct nvmet_req {
u64 error_slba;
};

+#define NVMET_MAX_MPOOL_BVEC 16
+extern struct kmem_cache *nvmet_bvec_cache;
extern struct workqueue_struct *buffered_io_wq;
extern struct workqueue_struct *zbd_wq;
extern struct workqueue_struct *nvmet_wq;
--
2.35.1