| Message ID | 1536057487-17267-3-git-send-email-hans.ml.holmberg@owltronix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [V2] lightnvm: pblk: stop recreating global caches | expand |
On 09/04/2018 12:38 PM, Hans Holmberg wrote: > From: Hans Holmberg <hans.holmberg@cnexlabs.com> > > Pblk should not create a set of global caches every time > a pblk instance is created. The global caches should be > made available only when there is one or more pblk instances. > > This patch bundles the global caches together with a kref > keeping track of whether the caches should be available or not. > > Also, turn the global pblk lock into a mutex that explicitly > protects the caches (as this was the only purpose of the lock). > > Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com> > --- > > Changes in V2: > * Turned the pblk global lock into a mutex protecting the > caches struct. > * Renamed the global caches to pblk_caches > * Refactored pblk_get_global_caches to handle only refcounting > and locking. > > drivers/lightnvm/pblk-init.c | 132 ++++++++++++++++++++++++++++--------------- > 1 file changed, 86 insertions(+), 46 deletions(-) > > diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c > index 9aebdee8e4c9..fb66bc84d5ca 100644 > --- a/drivers/lightnvm/pblk-init.c > +++ b/drivers/lightnvm/pblk-init.c > @@ -26,9 +26,24 @@ static unsigned int write_buffer_size; > module_param(write_buffer_size, uint, 0644); > MODULE_PARM_DESC(write_buffer_size, "number of entries in a write buffer"); > > -static struct kmem_cache *pblk_ws_cache, *pblk_rec_cache, *pblk_g_rq_cache, > - *pblk_w_rq_cache; > -static DECLARE_RWSEM(pblk_lock); > +struct pblk_global_caches { > + struct kmem_cache *ws; > + struct kmem_cache *rec; > + struct kmem_cache *g_rq; > + struct kmem_cache *w_rq; > + > + struct kref kref; > + > + struct mutex mutex; /* Ensures consistency between > + * caches and kref > + */ > +}; > + > +static struct pblk_global_caches pblk_caches = { > + .mutex = __MUTEX_INITIALIZER(pblk_caches.mutex), > + .kref = KREF_INIT(0), > +}; > + > struct bio_set pblk_bio_set; > > static int pblk_rw_io(struct request_queue *q, struct pblk *pblk, > @@ -307,53 +322,80 @@ static int pblk_set_addrf(struct pblk *pblk) > return 0; > } > > -static int pblk_init_global_caches(struct pblk *pblk) > +static int pblk_create_global_caches(void) > { > - down_write(&pblk_lock); > - pblk_ws_cache = kmem_cache_create("pblk_blk_ws", > + > + pblk_caches.ws = kmem_cache_create("pblk_blk_ws", > sizeof(struct pblk_line_ws), 0, 0, NULL); > - if (!pblk_ws_cache) { > - up_write(&pblk_lock); > + if (!pblk_caches.ws) > return -ENOMEM; > - } > > - pblk_rec_cache = kmem_cache_create("pblk_rec", > + pblk_caches.rec = kmem_cache_create("pblk_rec", > sizeof(struct pblk_rec_ctx), 0, 0, NULL); > - if (!pblk_rec_cache) { > - kmem_cache_destroy(pblk_ws_cache); > - up_write(&pblk_lock); > - return -ENOMEM; > - } > + if (!pblk_caches.rec) > + goto fail_destroy_ws; > > - pblk_g_rq_cache = kmem_cache_create("pblk_g_rq", pblk_g_rq_size, > + pblk_caches.g_rq = kmem_cache_create("pblk_g_rq", pblk_g_rq_size, > 0, 0, NULL); > - if (!pblk_g_rq_cache) { > - kmem_cache_destroy(pblk_ws_cache); > - kmem_cache_destroy(pblk_rec_cache); > - up_write(&pblk_lock); > - return -ENOMEM; > - } > + if (!pblk_caches.g_rq) > + goto fail_destroy_rec; > > - pblk_w_rq_cache = kmem_cache_create("pblk_w_rq", pblk_w_rq_size, > + pblk_caches.w_rq = kmem_cache_create("pblk_w_rq", pblk_w_rq_size, > 0, 0, NULL); > - if (!pblk_w_rq_cache) { > - kmem_cache_destroy(pblk_ws_cache); > - kmem_cache_destroy(pblk_rec_cache); > - kmem_cache_destroy(pblk_g_rq_cache); > - up_write(&pblk_lock); > - return -ENOMEM; > - } > - up_write(&pblk_lock); > + if (!pblk_caches.w_rq) > + goto fail_destroy_g_rq; > > return 0; > + > +fail_destroy_g_rq: > + kmem_cache_destroy(pblk_caches.g_rq); > +fail_destroy_rec: > + kmem_cache_destroy(pblk_caches.rec); > +fail_destroy_ws: > + kmem_cache_destroy(pblk_caches.ws); > + > + return -ENOMEM; > +} > + > +static int pblk_get_global_caches(void) > +{ > + int ret; > + > + mutex_lock(&pblk_caches.mutex); > + > + if (kref_read(&pblk_caches.kref) > 0) { > + kref_get(&pblk_caches.kref); > + mutex_unlock(&pblk_caches.mutex); > + return 0; > + } > + > + ret = pblk_create_global_caches(); > + > + if (!ret) > + kref_get(&pblk_caches.kref); > + > + mutex_unlock(&pblk_caches.mutex); > + > + return ret; > +} > + > +static void pblk_destroy_global_caches(struct kref *ref) > +{ > + struct pblk_global_caches *c; > + > + c = container_of(ref, struct pblk_global_caches, kref); > + > + kmem_cache_destroy(c->ws); > + kmem_cache_destroy(c->rec); > + kmem_cache_destroy(c->g_rq); > + kmem_cache_destroy(c->w_rq); > } > > -static void pblk_free_global_caches(struct pblk *pblk) > +static void pblk_put_global_caches(void) > { > - kmem_cache_destroy(pblk_ws_cache); > - kmem_cache_destroy(pblk_rec_cache); > - kmem_cache_destroy(pblk_g_rq_cache); > - kmem_cache_destroy(pblk_w_rq_cache); > + mutex_lock(&pblk_caches.mutex); > + kref_put(&pblk_caches.kref, pblk_destroy_global_caches); > + mutex_unlock(&pblk_caches.mutex); > } > > static int pblk_core_init(struct pblk *pblk) > @@ -382,7 +424,7 @@ static int pblk_core_init(struct pblk *pblk) > if (!pblk->pad_dist) > return -ENOMEM; > > - if (pblk_init_global_caches(pblk)) > + if (pblk_get_global_caches()) > goto fail_free_pad_dist; > > /* Internal bios can be at most the sectors signaled by the device. */ > @@ -391,27 +433,27 @@ static int pblk_core_init(struct pblk *pblk) > goto free_global_caches; > > ret = mempool_init_slab_pool(&pblk->gen_ws_pool, PBLK_GEN_WS_POOL_SIZE, > - pblk_ws_cache); > + pblk_caches.ws); > if (ret) > goto free_page_bio_pool; > > ret = mempool_init_slab_pool(&pblk->rec_pool, geo->all_luns, > - pblk_rec_cache); > + pblk_caches.rec); > if (ret) > goto free_gen_ws_pool; > > ret = mempool_init_slab_pool(&pblk->r_rq_pool, geo->all_luns, > - pblk_g_rq_cache); > + pblk_caches.g_rq); > if (ret) > goto free_rec_pool; > > ret = mempool_init_slab_pool(&pblk->e_rq_pool, geo->all_luns, > - pblk_g_rq_cache); > + pblk_caches.g_rq); > if (ret) > goto free_r_rq_pool; > > ret = mempool_init_slab_pool(&pblk->w_rq_pool, geo->all_luns, > - pblk_w_rq_cache); > + pblk_caches.w_rq); > if (ret) > goto free_e_rq_pool; > > @@ -457,7 +499,7 @@ static int pblk_core_init(struct pblk *pblk) > free_page_bio_pool: > mempool_exit(&pblk->page_bio_pool); > free_global_caches: > - pblk_free_global_caches(pblk); > + pblk_put_global_caches(); > fail_free_pad_dist: > kfree(pblk->pad_dist); > return -ENOMEM; > @@ -481,7 +523,7 @@ static void pblk_core_free(struct pblk *pblk) > mempool_exit(&pblk->e_rq_pool); > mempool_exit(&pblk->w_rq_pool); > > - pblk_free_global_caches(pblk); > + pblk_put_global_caches(); > kfree(pblk->pad_dist); > } > > @@ -1074,7 +1116,6 @@ static void pblk_exit(void *private, bool graceful) > { > struct pblk *pblk = private; > > - down_write(&pblk_lock); > pblk_gc_exit(pblk, graceful); > pblk_tear_down(pblk, graceful); > > @@ -1083,7 +1124,6 @@ static void pblk_exit(void *private, bool graceful) > #endif > > pblk_free(pblk); > - up_write(&pblk_lock); > } > > static sector_t pblk_capacity(void *private) > Thanks. Applied for 4.20.
diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c index 9aebdee8e4c9..fb66bc84d5ca 100644 --- a/drivers/lightnvm/pblk-init.c +++ b/drivers/lightnvm/pblk-init.c @@ -26,9 +26,24 @@ static unsigned int write_buffer_size; module_param(write_buffer_size, uint, 0644); MODULE_PARM_DESC(write_buffer_size, "number of entries in a write buffer"); -static struct kmem_cache *pblk_ws_cache, *pblk_rec_cache, *pblk_g_rq_cache, - *pblk_w_rq_cache; -static DECLARE_RWSEM(pblk_lock); +struct pblk_global_caches { + struct kmem_cache *ws; + struct kmem_cache *rec; + struct kmem_cache *g_rq; + struct kmem_cache *w_rq; + + struct kref kref; + + struct mutex mutex; /* Ensures consistency between + * caches and kref + */ +}; + +static struct pblk_global_caches pblk_caches = { + .mutex = __MUTEX_INITIALIZER(pblk_caches.mutex), + .kref = KREF_INIT(0), +}; + struct bio_set pblk_bio_set; static int pblk_rw_io(struct request_queue *q, struct pblk *pblk, @@ -307,53 +322,80 @@ static int pblk_set_addrf(struct pblk *pblk) return 0; } -static int pblk_init_global_caches(struct pblk *pblk) +static int pblk_create_global_caches(void) { - down_write(&pblk_lock); - pblk_ws_cache = kmem_cache_create("pblk_blk_ws", + + pblk_caches.ws = kmem_cache_create("pblk_blk_ws", sizeof(struct pblk_line_ws), 0, 0, NULL); - if (!pblk_ws_cache) { - up_write(&pblk_lock); + if (!pblk_caches.ws) return -ENOMEM; - } - pblk_rec_cache = kmem_cache_create("pblk_rec", + pblk_caches.rec = kmem_cache_create("pblk_rec", sizeof(struct pblk_rec_ctx), 0, 0, NULL); - if (!pblk_rec_cache) { - kmem_cache_destroy(pblk_ws_cache); - up_write(&pblk_lock); - return -ENOMEM; - } + if (!pblk_caches.rec) + goto fail_destroy_ws; - pblk_g_rq_cache = kmem_cache_create("pblk_g_rq", pblk_g_rq_size, + pblk_caches.g_rq = kmem_cache_create("pblk_g_rq", pblk_g_rq_size, 0, 0, NULL); - if (!pblk_g_rq_cache) { - kmem_cache_destroy(pblk_ws_cache); - kmem_cache_destroy(pblk_rec_cache); - up_write(&pblk_lock); - return -ENOMEM; - } + if (!pblk_caches.g_rq) + goto fail_destroy_rec; - pblk_w_rq_cache = kmem_cache_create("pblk_w_rq", pblk_w_rq_size, + pblk_caches.w_rq = kmem_cache_create("pblk_w_rq", pblk_w_rq_size, 0, 0, NULL); - if (!pblk_w_rq_cache) { - kmem_cache_destroy(pblk_ws_cache); - kmem_cache_destroy(pblk_rec_cache); - kmem_cache_destroy(pblk_g_rq_cache); - up_write(&pblk_lock); - return -ENOMEM; - } - up_write(&pblk_lock); + if (!pblk_caches.w_rq) + goto fail_destroy_g_rq; return 0; + +fail_destroy_g_rq: + kmem_cache_destroy(pblk_caches.g_rq); +fail_destroy_rec: + kmem_cache_destroy(pblk_caches.rec); +fail_destroy_ws: + kmem_cache_destroy(pblk_caches.ws); + + return -ENOMEM; +} + +static int pblk_get_global_caches(void) +{ + int ret; + + mutex_lock(&pblk_caches.mutex); + + if (kref_read(&pblk_caches.kref) > 0) { + kref_get(&pblk_caches.kref); + mutex_unlock(&pblk_caches.mutex); + return 0; + } + + ret = pblk_create_global_caches(); + + if (!ret) + kref_get(&pblk_caches.kref); + + mutex_unlock(&pblk_caches.mutex); + + return ret; +} + +static void pblk_destroy_global_caches(struct kref *ref) +{ + struct pblk_global_caches *c; + + c = container_of(ref, struct pblk_global_caches, kref); + + kmem_cache_destroy(c->ws); + kmem_cache_destroy(c->rec); + kmem_cache_destroy(c->g_rq); + kmem_cache_destroy(c->w_rq); } -static void pblk_free_global_caches(struct pblk *pblk) +static void pblk_put_global_caches(void) { - kmem_cache_destroy(pblk_ws_cache); - kmem_cache_destroy(pblk_rec_cache); - kmem_cache_destroy(pblk_g_rq_cache); - kmem_cache_destroy(pblk_w_rq_cache); + mutex_lock(&pblk_caches.mutex); + kref_put(&pblk_caches.kref, pblk_destroy_global_caches); + mutex_unlock(&pblk_caches.mutex); } static int pblk_core_init(struct pblk *pblk) @@ -382,7 +424,7 @@ static int pblk_core_init(struct pblk *pblk) if (!pblk->pad_dist) return -ENOMEM; - if (pblk_init_global_caches(pblk)) + if (pblk_get_global_caches()) goto fail_free_pad_dist; /* Internal bios can be at most the sectors signaled by the device. */ @@ -391,27 +433,27 @@ static int pblk_core_init(struct pblk *pblk) goto free_global_caches; ret = mempool_init_slab_pool(&pblk->gen_ws_pool, PBLK_GEN_WS_POOL_SIZE, - pblk_ws_cache); + pblk_caches.ws); if (ret) goto free_page_bio_pool; ret = mempool_init_slab_pool(&pblk->rec_pool, geo->all_luns, - pblk_rec_cache); + pblk_caches.rec); if (ret) goto free_gen_ws_pool; ret = mempool_init_slab_pool(&pblk->r_rq_pool, geo->all_luns, - pblk_g_rq_cache); + pblk_caches.g_rq); if (ret) goto free_rec_pool; ret = mempool_init_slab_pool(&pblk->e_rq_pool, geo->all_luns, - pblk_g_rq_cache); + pblk_caches.g_rq); if (ret) goto free_r_rq_pool; ret = mempool_init_slab_pool(&pblk->w_rq_pool, geo->all_luns, - pblk_w_rq_cache); + pblk_caches.w_rq); if (ret) goto free_e_rq_pool; @@ -457,7 +499,7 @@ static int pblk_core_init(struct pblk *pblk) free_page_bio_pool: mempool_exit(&pblk->page_bio_pool); free_global_caches: - pblk_free_global_caches(pblk); + pblk_put_global_caches(); fail_free_pad_dist: kfree(pblk->pad_dist); return -ENOMEM; @@ -481,7 +523,7 @@ static void pblk_core_free(struct pblk *pblk) mempool_exit(&pblk->e_rq_pool); mempool_exit(&pblk->w_rq_pool); - pblk_free_global_caches(pblk); + pblk_put_global_caches(); kfree(pblk->pad_dist); } @@ -1074,7 +1116,6 @@ static void pblk_exit(void *private, bool graceful) { struct pblk *pblk = private; - down_write(&pblk_lock); pblk_gc_exit(pblk, graceful); pblk_tear_down(pblk, graceful); @@ -1083,7 +1124,6 @@ static void pblk_exit(void *private, bool graceful) #endif pblk_free(pblk); - up_write(&pblk_lock); } static sector_t pblk_capacity(void *private)