X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fosc%2Fosc_page.c;h=eb054a9963eb688a45e9247b445779a7e57a8941;hp=32fb5f494ff8f959c7a1b300882273fc9929f234;hb=df497dc560062a0a0c7178498cba8853843d39f1;hpb=364c4cdb58ed75996017d35dcbbc7e7acc6d076e diff --git a/lustre/osc/osc_page.c b/lustre/osc/osc_page.c index 32fb5f4..eb054a9 100644 --- a/lustre/osc/osc_page.c +++ b/lustre/osc/osc_page.c @@ -27,7 +27,7 @@ * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. * - * Copyright (c) 2011, Whamcloud, Inc. + * Copyright (c) 2011, 2013, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ @@ -36,17 +36,23 @@ * Implementation of cl_page for OSC layer. * * Author: Nikita Danilov + * Author: Jinshan Xiong */ #define DEBUG_SUBSYSTEM S_OSC #include "osc_cl_internal.h" -/** \addtogroup osc - * @{ +static void osc_lru_del(struct client_obd *cli, struct osc_page *opg); +static void osc_lru_use(struct client_obd *cli, struct osc_page *opg); +static int osc_lru_reserve(const struct lu_env *env, struct osc_object *obj, + struct osc_page *opg); + +/** \addtogroup osc + * @{ */ -/* +/* * Comment out osc_page_protected because it may sleep inside the * the client_obd_list_lock. * client_obd_list_lock -> osc_ap_completion -> osc_completion -> @@ -58,33 +64,33 @@ static int osc_page_is_dlocked(const struct lu_env *env, const struct osc_page *opg, enum cl_lock_mode mode, int pending, int unref) { - struct cl_page *page; - struct osc_object *obj; - struct osc_thread_info *info; - struct ldlm_res_id *resname; - struct lustre_handle *lockh; - ldlm_policy_data_t *policy; - ldlm_mode_t dlmmode; - int flags; - - cfs_might_sleep(); - - info = osc_env_info(env); - resname = &info->oti_resname; - policy = &info->oti_policy; - lockh = &info->oti_handle; - page = opg->ops_cl.cpl_page; - obj = cl2osc(opg->ops_cl.cpl_obj); - - flags = LDLM_FL_TEST_LOCK | LDLM_FL_BLOCK_GRANTED; - if (pending) - flags |= LDLM_FL_CBPENDING; - - dlmmode = osc_cl_lock2ldlm(mode) | LCK_PW; - osc_lock_build_res(env, obj, resname); - osc_index2policy(policy, page->cp_obj, page->cp_index, page->cp_index); - return osc_match_base(osc_export(obj), resname, LDLM_EXTENT, policy, - dlmmode, &flags, NULL, lockh, unref); + struct cl_page *page; + struct osc_object *obj; + struct osc_thread_info *info; + struct ldlm_res_id *resname; + struct lustre_handle *lockh; + ldlm_policy_data_t *policy; + ldlm_mode_t dlmmode; + __u64 flags; + + might_sleep(); + + info = osc_env_info(env); + resname = &info->oti_resname; + policy = &info->oti_policy; + lockh = &info->oti_handle; + page = opg->ops_cl.cpl_page; + obj = cl2osc(opg->ops_cl.cpl_obj); + + flags = LDLM_FL_TEST_LOCK | LDLM_FL_BLOCK_GRANTED; + if (pending) + flags |= LDLM_FL_CBPENDING; + + dlmmode = osc_cl_lock2ldlm(mode) | LCK_PW; + osc_lock_build_res(env, obj, resname); + osc_index2policy(policy, page->cp_obj, osc_index(opg), osc_index(opg)); + return osc_match_base(osc_export(obj), resname, LDLM_EXTENT, policy, + dlmmode, &flags, NULL, lockh, unref); } /** @@ -119,10 +125,10 @@ static int osc_page_protected(const struct lu_env *env, hdr = cl_object_header(opg->ops_cl.cpl_obj); descr = &osc_env_info(env)->oti_descr; descr->cld_mode = mode; - descr->cld_start = page->cp_index; - descr->cld_end = page->cp_index; - cfs_spin_lock(&hdr->coh_lock_guard); - cfs_list_for_each_entry(scan, &hdr->coh_locks, cll_linkage) { + descr->cld_start = osc_index(opg); + descr->cld_end = osc_index(opg); + spin_lock(&hdr->coh_lock_guard); + list_for_each_entry(scan, &hdr->coh_locks, cll_linkage) { /* * Lock-less sub-lock has to be either in HELD state * (when io is actively going on), or in CACHED state, @@ -139,7 +145,7 @@ static int osc_page_protected(const struct lu_env *env, break; } } - cfs_spin_unlock(&hdr->coh_lock_guard); + spin_unlock(&hdr->coh_lock_guard); } return result; } @@ -157,35 +163,26 @@ static int osc_page_protected(const struct lu_env *env, * Page operations. * */ -static void osc_page_fini(const struct lu_env *env, - struct cl_page_slice *slice) -{ - struct osc_page *opg = cl2osc_page(slice); - CDEBUG(D_TRACE, "%p\n", opg); - LASSERT(opg->ops_lock == NULL); - OBD_SLAB_FREE_PTR(opg, osc_page_kmem); -} - static void osc_page_transfer_get(struct osc_page *opg, const char *label) { - struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page); + struct cl_page *page = opg->ops_cl.cpl_page; - LASSERT(!opg->ops_transfer_pinned); - cl_page_get(page); - lu_ref_add_atomic(&page->cp_reference, label, page); - opg->ops_transfer_pinned = 1; + LASSERT(!opg->ops_transfer_pinned); + cl_page_get(page); + lu_ref_add_atomic(&page->cp_reference, label, page); + opg->ops_transfer_pinned = 1; } static void osc_page_transfer_put(const struct lu_env *env, - struct osc_page *opg) + struct osc_page *opg) { - struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page); + struct cl_page *page = opg->ops_cl.cpl_page; - if (opg->ops_transfer_pinned) { - lu_ref_del(&page->cp_reference, "transfer", page); - opg->ops_transfer_pinned = 0; - cl_page_put(env, page); - } + if (opg->ops_transfer_pinned) { + opg->ops_transfer_pinned = 0; + lu_ref_del(&page->cp_reference, "transfer", page); + cl_page_put(env, page); + } } /** @@ -196,18 +193,20 @@ static void osc_page_transfer_put(const struct lu_env *env, static void osc_page_transfer_add(const struct lu_env *env, struct osc_page *opg, enum cl_req_type crt) { - struct osc_object *obj; + struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj); - obj = cl2osc(opg->ops_cl.cpl_obj); - cfs_spin_lock(&obj->oo_seatbelt); - cfs_list_add(&opg->ops_inflight, &obj->oo_inflight[crt]); - opg->ops_submitter = cfs_current(); - cfs_spin_unlock(&obj->oo_seatbelt); + /* ops_lru and ops_inflight share the same field, so take it from LRU + * first and then use it as inflight. */ + osc_lru_use(osc_cli(obj), opg); + + spin_lock(&obj->oo_seatbelt); + list_add(&opg->ops_inflight, &obj->oo_inflight[crt]); + opg->ops_submitter = current; + spin_unlock(&obj->oo_seatbelt); } -static int osc_page_cache_add(const struct lu_env *env, - const struct cl_page_slice *slice, - struct cl_io *unused) +int osc_page_cache_add(const struct lu_env *env, + const struct cl_page_slice *slice, struct cl_io *io) { struct osc_page *opg = cl2osc_page(slice); int result; @@ -216,11 +215,12 @@ static int osc_page_cache_add(const struct lu_env *env, LINVRNT(osc_page_protected(env, opg, CLM_WRITE, 0)); osc_page_transfer_get(opg, "transfer\0cache"); - result = osc_queue_async_io(env, opg); + result = osc_queue_async_io(env, io, opg); if (result != 0) osc_page_transfer_put(env, opg); else osc_page_transfer_add(env, opg, CRT_WRITE); + RETURN(result); } @@ -232,95 +232,29 @@ void osc_index2policy(ldlm_policy_data_t *policy, const struct cl_object *obj, policy->l_extent.end = cl_offset(obj, end + 1) - 1; } -static int osc_page_addref_lock(const struct lu_env *env, - struct osc_page *opg, - struct cl_lock *lock) -{ - struct osc_lock *olock; - int rc; - - LASSERT(opg->ops_lock == NULL); - - olock = osc_lock_at(lock); - if (cfs_atomic_inc_return(&olock->ols_pageref) <= 0) { - cfs_atomic_dec(&olock->ols_pageref); - cl_lock_put(env, lock); - rc = 1; - } else { - opg->ops_lock = lock; - rc = 0; - } - return rc; -} - -static void osc_page_putref_lock(const struct lu_env *env, - struct osc_page *opg) -{ - struct cl_lock *lock = opg->ops_lock; - struct osc_lock *olock; - - LASSERT(lock != NULL); - olock = osc_lock_at(lock); - - cfs_atomic_dec(&olock->ols_pageref); - opg->ops_lock = NULL; - - cl_lock_put(env, lock); -} - static int osc_page_is_under_lock(const struct lu_env *env, - const struct cl_page_slice *slice, - struct cl_io *unused) -{ - struct cl_lock *lock; - int result; - - ENTRY; - lock = cl_lock_at_page(env, slice->cpl_obj, slice->cpl_page, - NULL, 1, 0); - if (lock != NULL && - osc_page_addref_lock(env, cl2osc_page(slice), lock) == 0) - result = -EBUSY; - else - result = -ENODATA; - RETURN(result); -} - -static void osc_page_disown(const struct lu_env *env, - const struct cl_page_slice *slice, - struct cl_io *io) -{ - struct osc_page *opg = cl2osc_page(slice); - - if (unlikely(opg->ops_lock)) - osc_page_putref_lock(env, opg); -} - -static void osc_page_completion_read(const struct lu_env *env, - const struct cl_page_slice *slice, - int ioret) + const struct cl_page_slice *slice, + struct cl_io *unused, pgoff_t *max_index) { - struct osc_page *opg = cl2osc_page(slice); - - if (likely(opg->ops_lock)) - osc_page_putref_lock(env, opg); -} + struct osc_page *opg = cl2osc_page(slice); + struct cl_lock *lock; + int result = -ENODATA; + ENTRY; -static int osc_page_fail(const struct lu_env *env, - const struct cl_page_slice *slice, - struct cl_io *unused) -{ - /* - * Cached read? - */ - LBUG(); - return 0; + *max_index = 0; + lock = cl_lock_at_pgoff(env, slice->cpl_obj, osc_index(opg), + NULL, 1, 0); + if (lock != NULL) { + *max_index = lock->cll_descr.cld_end; + cl_lock_put(env, lock); + result = 0; + } + RETURN(result); } - -static const char *osc_list(cfs_list_t *head) +static const char *osc_list(struct list_head *head) { - return cfs_list_empty(head) ? "-" : "+"; + return list_empty(head) ? "-" : "+"; } static inline cfs_time_t osc_submit_duration(struct osc_page *opg) @@ -340,18 +274,17 @@ static int osc_page_print(const struct lu_env *env, struct osc_object *obj = cl2osc(slice->cpl_obj); struct client_obd *cli = &osc_export(obj)->exp_obd->u.cli; - return (*printer)(env, cookie, LUSTRE_OSC_NAME"-page@%p: " - "1< %#x %d %u %s %s %s > " + return (*printer)(env, cookie, LUSTRE_OSC_NAME"-page@%p %lu: " + "1< %#x %d %u %s %s > " "2< "LPU64" %u %u %#x %#x | %p %p %p > " - "3< %s %p %d %lu %d > " - "4< %d %d %d %lu %s | %s %s %s %s > " - "5< %s %s %s %s | %d %s %s | %d %s %s>\n", - opg, + "3< %s %p %d %lu %d > " + "4< %d %d %d %lu %s | %s %s %s %s > " + "5< %s %s %s %s | %d %s | %d %s %s>\n", + opg, osc_index(opg), /* 1 */ oap->oap_magic, oap->oap_cmd, oap->oap_interrupted, osc_list(&oap->oap_pending_item), - osc_list(&oap->oap_urgent_item), osc_list(&oap->oap_rpc_item), /* 2 */ oap->oap_obj_off, oap->oap_page_off, oap->oap_count, @@ -375,12 +308,11 @@ static int osc_page_print(const struct lu_env *env, osc_list(&obj->oo_hp_ready_item), osc_list(&obj->oo_write_item), osc_list(&obj->oo_read_item), - obj->oo_read_pages.oop_num_pending, - osc_list(&obj->oo_read_pages.oop_pending), - osc_list(&obj->oo_read_pages.oop_urgent), - obj->oo_write_pages.oop_num_pending, - osc_list(&obj->oo_write_pages.oop_pending), - osc_list(&obj->oo_write_pages.oop_urgent)); + atomic_read(&obj->oo_nr_reads), + osc_list(&obj->oo_reading_exts), + atomic_read(&obj->oo_nr_writes), + osc_list(&obj->oo_hp_exts), + osc_list(&obj->oo_urgent_exts)); } static void osc_page_delete(const struct lu_env *env, @@ -395,16 +327,36 @@ static void osc_page_delete(const struct lu_env *env, ENTRY; CDEBUG(D_TRACE, "%p\n", opg); osc_page_transfer_put(env, opg); - rc = osc_teardown_async_page(obj, opg); - if (rc) { - CL_PAGE_DEBUG(D_ERROR, env, cl_page_top(slice->cpl_page), - "Trying to teardown failed: %d\n", rc); - LASSERT(0); - } - cfs_spin_lock(&obj->oo_seatbelt); - cfs_list_del_init(&opg->ops_inflight); - cfs_spin_unlock(&obj->oo_seatbelt); - EXIT; + rc = osc_teardown_async_page(env, obj, opg); + if (rc) { + CL_PAGE_DEBUG(D_ERROR, env, slice->cpl_page, + "Trying to teardown failed: %d\n", rc); + LASSERT(0); + } + + spin_lock(&obj->oo_seatbelt); + if (opg->ops_submitter != NULL) { + LASSERT(!list_empty(&opg->ops_inflight)); + list_del_init(&opg->ops_inflight); + opg->ops_submitter = NULL; + } + spin_unlock(&obj->oo_seatbelt); + + osc_lru_del(osc_cli(obj), opg); + + if (slice->cpl_page->cp_type == CPT_CACHEABLE) { + void *value; + + spin_lock(&obj->oo_tree_lock); + value = radix_tree_delete(&obj->oo_tree, osc_index(opg)); + if (value != NULL) + --obj->oo_npages; + spin_unlock(&obj->oo_tree_lock); + + LASSERT(ergo(value != NULL, value == opg)); + } + + EXIT; } void osc_page_clip(const struct lu_env *env, const struct cl_page_slice *slice, @@ -417,101 +369,553 @@ void osc_page_clip(const struct lu_env *env, const struct cl_page_slice *slice, opg->ops_from = from; opg->ops_to = to; - cfs_spin_lock(&oap->oap_lock); - oap->oap_async_flags |= ASYNC_COUNT_STABLE; - cfs_spin_unlock(&oap->oap_lock); + spin_lock(&oap->oap_lock); + oap->oap_async_flags |= ASYNC_COUNT_STABLE; + spin_unlock(&oap->oap_lock); } static int osc_page_cancel(const struct lu_env *env, const struct cl_page_slice *slice) { - struct osc_page *opg = cl2osc_page(slice); - struct osc_async_page *oap = &opg->ops_oap; + struct osc_page *opg = cl2osc_page(slice); int rc = 0; LINVRNT(osc_page_protected(env, opg, CLM_READ, 0)); - client_obd_list_lock(&oap->oap_cli->cl_loi_list_lock); /* Check if the transferring against this page * is completed, or not even queued. */ if (opg->ops_transfer_pinned) /* FIXME: may not be interrupted.. */ rc = osc_cancel_async_page(env, opg); LASSERT(ergo(rc == 0, opg->ops_transfer_pinned == 0)); - client_obd_list_unlock(&oap->oap_cli->cl_loi_list_lock); return rc; } +static int osc_page_flush(const struct lu_env *env, + const struct cl_page_slice *slice, + struct cl_io *io) +{ + struct osc_page *opg = cl2osc_page(slice); + int rc = 0; + ENTRY; + rc = osc_flush_async_page(env, io, opg); + RETURN(rc); +} + static const struct cl_page_operations osc_page_ops = { - .cpo_fini = osc_page_fini, - .cpo_print = osc_page_print, - .cpo_delete = osc_page_delete, - .cpo_is_under_lock = osc_page_is_under_lock, - .cpo_disown = osc_page_disown, - .io = { - [CRT_READ] = { - .cpo_cache_add = osc_page_fail, - .cpo_completion = osc_page_completion_read - }, - [CRT_WRITE] = { - .cpo_cache_add = osc_page_cache_add - } - }, - .cpo_clip = osc_page_clip, - .cpo_cancel = osc_page_cancel + .cpo_print = osc_page_print, + .cpo_delete = osc_page_delete, + .cpo_is_under_lock = osc_page_is_under_lock, + .cpo_clip = osc_page_clip, + .cpo_cancel = osc_page_cancel, + .cpo_flush = osc_page_flush }; -struct cl_page *osc_page_init(const struct lu_env *env, - struct cl_object *obj, - struct cl_page *page, cfs_page_t *vmpage) +int osc_page_init(const struct lu_env *env, struct cl_object *obj, + struct cl_page *page, pgoff_t index) { - struct osc_object *osc = cl2osc(obj); - struct osc_page *opg; - int result; + struct osc_object *osc = cl2osc(obj); + struct osc_page *opg = cl_object_page_slice(obj, page); + int result; - OBD_SLAB_ALLOC_PTR_GFP(opg, osc_page_kmem, CFS_ALLOC_IO); - if (opg != NULL) { - opg->ops_from = 0; - opg->ops_to = CFS_PAGE_SIZE; - - result = osc_prep_async_page(osc, opg, vmpage, - cl_offset(obj, page->cp_index)); - if (result == 0) { - struct osc_io *oio = osc_env_io(env); - opg->ops_srvlock = osc_io_srvlock(oio); - cl_page_slice_add(page, &opg->ops_cl, obj, - &osc_page_ops); - } - /* - * Cannot assert osc_page_protected() here as read-ahead - * creates temporary pages outside of a lock. - */ -#ifdef INVARIANT_CHECK - opg->ops_temp = !osc_page_protected(env, opg, CLM_READ, 1); + opg->ops_from = 0; + opg->ops_to = PAGE_CACHE_SIZE; + + result = osc_prep_async_page(osc, opg, page->cp_vmpage, + cl_offset(obj, index)); + if (result == 0) { + struct osc_io *oio = osc_env_io(env); + opg->ops_srvlock = osc_io_srvlock(oio); + cl_page_slice_add(page, &opg->ops_cl, obj, index, + &osc_page_ops); + } + /* + * Cannot assert osc_page_protected() here as read-ahead + * creates temporary pages outside of a lock. + */ +#ifdef CONFIG_LUSTRE_DEBUG_EXPENSIVE_CHECK + opg->ops_temp = !osc_page_protected(env, opg, CLM_READ, 1); #endif - CFS_INIT_LIST_HEAD(&opg->ops_inflight); - } else - result = -ENOMEM; - return ERR_PTR(result); + /* ops_inflight and ops_lru are the same field, but it doesn't + * hurt to initialize it twice :-) */ + INIT_LIST_HEAD(&opg->ops_inflight); + INIT_LIST_HEAD(&opg->ops_lru); + + /* reserve an LRU space for this page */ + if (page->cp_type == CPT_CACHEABLE && result == 0) { + result = osc_lru_reserve(env, osc, opg); + if (result == 0) { + spin_lock(&osc->oo_tree_lock); + result = radix_tree_insert(&osc->oo_tree, index, opg); + if (result == 0) + ++osc->oo_npages; + spin_unlock(&osc->oo_tree_lock); + LASSERT(result == 0); + } + } + + return result; +} + +int osc_over_unstable_soft_limit(struct client_obd *cli) +{ + long obd_upages, obd_dpages, osc_upages; + + /* Can't check cli->cl_unstable_count, therefore, no soft limit */ + if (cli == NULL) + return 0; + + obd_upages = atomic_read(&obd_unstable_pages); + obd_dpages = atomic_read(&obd_dirty_pages); + + osc_upages = atomic_read(&cli->cl_unstable_count); + + /* obd_max_dirty_pages is the max number of (dirty + unstable) + * pages allowed at any given time. To simulate an unstable page + * only limit, we subtract the current number of dirty pages + * from this max. This difference is roughly the amount of pages + * currently available for unstable pages. Thus, the soft limit + * is half of that difference. Check osc_upages to ensure we don't + * set SOFT_SYNC for OSCs without any outstanding unstable pages. */ + return osc_upages != 0 && + obd_upages >= (obd_max_dirty_pages - obd_dpages) / 2; } /** * Helper function called by osc_io_submit() for every page in an immediate * transfer (i.e., transferred synchronously). */ -void osc_io_submit_page(const struct lu_env *env, - struct osc_io *oio, struct osc_page *opg, - enum cl_req_type crt) +void osc_page_submit(const struct lu_env *env, struct osc_page *opg, + enum cl_req_type crt, int brw_flags) { - LINVRNT(osc_page_protected(env, opg, - crt == CRT_WRITE ? CLM_WRITE : CLM_READ, 1)); + struct osc_async_page *oap = &opg->ops_oap; + struct osc_object *obj = oap->oap_obj; + + LINVRNT(osc_page_protected(env, opg, + crt == CRT_WRITE ? CLM_WRITE : CLM_READ, 1)); + + LASSERTF(oap->oap_magic == OAP_MAGIC, "Bad oap magic: oap %p, " + "magic 0x%x\n", oap, oap->oap_magic); + LASSERT(oap->oap_async_flags & ASYNC_READY); + LASSERT(oap->oap_async_flags & ASYNC_COUNT_STABLE); + + oap->oap_cmd = crt == CRT_WRITE ? OBD_BRW_WRITE : OBD_BRW_READ; + oap->oap_page_off = opg->ops_from; + oap->oap_count = opg->ops_to - opg->ops_from; + oap->oap_brw_flags = OBD_BRW_SYNC | brw_flags; + + if (osc_over_unstable_soft_limit(oap->oap_cli)) + oap->oap_brw_flags |= OBD_BRW_SOFT_SYNC; + + if (!client_is_remote(osc_export(obj)) && + cfs_capable(CFS_CAP_SYS_RESOURCE)) { + oap->oap_brw_flags |= OBD_BRW_NOQUOTA; + oap->oap_cmd |= OBD_BRW_NOQUOTA; + } + + opg->ops_submit_time = cfs_time_current(); + osc_page_transfer_get(opg, "transfer\0imm"); + osc_page_transfer_add(env, opg, crt); +} + +/* --------------- LRU page management ------------------ */ + +/* OSC is a natural place to manage LRU pages as applications are specialized + * to write OSC by OSC. Ideally, if one OSC is used more frequently it should + * occupy more LRU slots. On the other hand, we should avoid using up all LRU + * slots (client_obd::cl_lru_left) otherwise process has to be put into sleep + * for free LRU slots - this will be very bad so the algorithm requires each + * OSC to free slots voluntarily to maintain a reasonable number of free slots + * at any time. + */ + +static CFS_DECL_WAITQ(osc_lru_waitq); +/* LRU pages are freed in batch mode. OSC should at least free this + * number of pages to avoid running out of LRU budget, and.. */ +static const int lru_shrink_min = 2 << (20 - PAGE_CACHE_SHIFT); /* 2M */ +/* free this number at most otherwise it will take too long time to finsih. */ +static const int lru_shrink_max = 8 << (20 - PAGE_CACHE_SHIFT); /* 8M */ - osc_queue_sync_page(env, opg, - crt == CRT_WRITE ? OBD_BRW_WRITE : OBD_BRW_READ, - osc_io_srvlock(oio) ? OBD_BRW_SRVLOCK : 0); +/* Check if we can free LRU slots from this OSC. If there exists LRU waiters, + * we should free slots aggressively. In this way, slots are freed in a steady + * step to maintain fairness among OSCs. + * + * Return how many LRU pages should be freed. */ +static int osc_cache_too_much(struct client_obd *cli) +{ + struct cl_client_cache *cache = cli->cl_cache; + int pages = atomic_read(&cli->cl_lru_in_list); + unsigned long budget; + + budget = cache->ccc_lru_max / atomic_read(&cache->ccc_users); + + /* if it's going to run out LRU slots, we should free some, but not + * too much to maintain faireness among OSCs. */ + if (atomic_read(cli->cl_lru_left) < cache->ccc_lru_max >> 4) { + if (pages >= budget) + return lru_shrink_max; + else if (pages >= budget / 2) + return lru_shrink_min; + } else if (pages >= budget * 2) + return lru_shrink_min; + return 0; +} + +int lru_queue_work(const struct lu_env *env, void *data) +{ + struct client_obd *cli = data; + + CDEBUG(D_CACHE, "Run LRU work for client obd %p.\n", cli); + + if (osc_cache_too_much(cli)) + osc_lru_shrink(env, cli, lru_shrink_max, true); + + RETURN(0); +} + +void osc_lru_add_batch(struct client_obd *cli, struct list_head *plist) +{ + struct list_head lru = LIST_HEAD_INIT(lru); + struct osc_async_page *oap; + int npages = 0; + + list_for_each_entry(oap, plist, oap_pending_item) { + struct osc_page *opg = oap2osc_page(oap); + + if (!opg->ops_in_lru) + continue; + + ++npages; + LASSERT(list_empty(&opg->ops_lru)); + list_add(&opg->ops_lru, &lru); + } + + if (npages > 0) { + client_obd_list_lock(&cli->cl_lru_list_lock); + list_splice_tail(&lru, &cli->cl_lru_list); + atomic_sub(npages, &cli->cl_lru_busy); + atomic_add(npages, &cli->cl_lru_in_list); + client_obd_list_unlock(&cli->cl_lru_list_lock); + + /* XXX: May set force to be true for better performance */ + if (osc_cache_too_much(cli)) + (void)ptlrpcd_queue_work(cli->cl_lru_work); + } +} + +static void __osc_lru_del(struct client_obd *cli, struct osc_page *opg) +{ + LASSERT(atomic_read(&cli->cl_lru_in_list) > 0); + list_del_init(&opg->ops_lru); + atomic_dec(&cli->cl_lru_in_list); +} + +/** + * Page is being destroyed. The page may be not in LRU list, if the transfer + * has never finished(error occurred). + */ +static void osc_lru_del(struct client_obd *cli, struct osc_page *opg) +{ + if (opg->ops_in_lru) { + client_obd_list_lock(&cli->cl_lru_list_lock); + if (!list_empty(&opg->ops_lru)) { + __osc_lru_del(cli, opg); + } else { + LASSERT(atomic_read(&cli->cl_lru_busy) > 0); + atomic_dec(&cli->cl_lru_busy); + } + client_obd_list_unlock(&cli->cl_lru_list_lock); + + atomic_inc(cli->cl_lru_left); + /* this is a great place to release more LRU pages if + * this osc occupies too many LRU pages and kernel is + * stealing one of them. */ + if (!memory_pressure_get()) + (void)ptlrpcd_queue_work(cli->cl_lru_work); + wake_up(&osc_lru_waitq); + } else { + LASSERT(list_empty(&opg->ops_lru)); + } +} + +/** + * Delete page from LRUlist for redirty. + */ +static void osc_lru_use(struct client_obd *cli, struct osc_page *opg) +{ + /* If page is being transfered for the first time, + * ops_lru should be empty */ + if (opg->ops_in_lru && !list_empty(&opg->ops_lru)) { + client_obd_list_lock(&cli->cl_lru_list_lock); + __osc_lru_del(cli, opg); + client_obd_list_unlock(&cli->cl_lru_list_lock); + atomic_inc(&cli->cl_lru_busy); + } +} + +static void discard_pagevec(const struct lu_env *env, struct cl_io *io, + struct cl_page **pvec, int max_index) +{ + int i; + + for (i = 0; i < max_index; i++) { + struct cl_page *page = pvec[i]; + + LASSERT(cl_page_is_owned(page, io)); + cl_page_discard(env, io, page); + cl_page_disown(env, io, page); + cl_page_put(env, page); + + pvec[i] = NULL; + } +} + +/** + * Drop @target of pages from LRU at most. + */ +int osc_lru_shrink(const struct lu_env *env, struct client_obd *cli, + int target, bool force) +{ + struct cl_io *io; + struct cl_object *clobj = NULL; + struct cl_page **pvec; + struct osc_page *opg; + int maxscan = 0; + int count = 0; + int index = 0; + int rc = 0; + ENTRY; + + LASSERT(atomic_read(&cli->cl_lru_in_list) >= 0); + if (atomic_read(&cli->cl_lru_in_list) == 0 || target <= 0) + RETURN(0); + + if (!force) { + if (atomic_read(&cli->cl_lru_shrinkers) > 0) + RETURN(-EBUSY); + + if (atomic_inc_return(&cli->cl_lru_shrinkers) > 1) { + atomic_dec(&cli->cl_lru_shrinkers); + RETURN(-EBUSY); + } + } else { + atomic_inc(&cli->cl_lru_shrinkers); + } + + pvec = (struct cl_page **)osc_env_info(env)->oti_pvec; + io = &osc_env_info(env)->oti_io; + + client_obd_list_lock(&cli->cl_lru_list_lock); + maxscan = min(target << 1, atomic_read(&cli->cl_lru_in_list)); + while (!list_empty(&cli->cl_lru_list)) { + struct cl_page *page; + bool will_free = false; + + if (--maxscan < 0) + break; + + opg = list_entry(cli->cl_lru_list.next, struct osc_page, + ops_lru); + page = opg->ops_cl.cpl_page; + if (cl_page_in_use_noref(page)) { + list_move_tail(&opg->ops_lru, &cli->cl_lru_list); + continue; + } + + LASSERT(page->cp_obj != NULL); + if (clobj != page->cp_obj) { + struct cl_object *tmp = page->cp_obj; + + cl_object_get(tmp); + client_obd_list_unlock(&cli->cl_lru_list_lock); + + if (clobj != NULL) { + discard_pagevec(env, io, pvec, index); + index = 0; + + cl_io_fini(env, io); + cl_object_put(env, clobj); + clobj = NULL; + } + + clobj = tmp; + io->ci_obj = clobj; + io->ci_ignore_layout = 1; + rc = cl_io_init(env, io, CIT_MISC, clobj); + + client_obd_list_lock(&cli->cl_lru_list_lock); + + if (rc != 0) + break; + + ++maxscan; + continue; + } + + if (cl_page_own_try(env, io, page) == 0) { + if (!cl_page_in_use_noref(page)) { + /* remove it from lru list earlier to avoid + * lock contention */ + __osc_lru_del(cli, opg); + opg->ops_in_lru = 0; /* will be discarded */ + + cl_page_get(page); + will_free = true; + } else { + cl_page_disown(env, io, page); + } + } + + if (!will_free) { + list_move_tail(&opg->ops_lru, &cli->cl_lru_list); + continue; + } + + /* Don't discard and free the page with cl_lru_list held */ + pvec[index++] = page; + if (unlikely(index == OTI_PVEC_SIZE)) { + client_obd_list_unlock(&cli->cl_lru_list_lock); + discard_pagevec(env, io, pvec, index); + index = 0; + + client_obd_list_lock(&cli->cl_lru_list_lock); + } + + if (++count >= target) + break; + } + client_obd_list_unlock(&cli->cl_lru_list_lock); + + if (clobj != NULL) { + discard_pagevec(env, io, pvec, index); + + cl_io_fini(env, io); + cl_object_put(env, clobj); + } + + atomic_dec(&cli->cl_lru_shrinkers); + if (count > 0) { + atomic_add(count, cli->cl_lru_left); + wake_up_all(&osc_lru_waitq); + } + RETURN(count > 0 ? count : rc); +} + +static inline int max_to_shrink(struct client_obd *cli) +{ + return min(atomic_read(&cli->cl_lru_in_list) >> 1, lru_shrink_max); +} + +int osc_lru_reclaim(struct client_obd *cli) +{ + struct cl_env_nest nest; + struct lu_env *env; + struct cl_client_cache *cache = cli->cl_cache; + int max_scans; + int rc = 0; + ENTRY; + + LASSERT(cache != NULL); + LASSERT(!list_empty(&cache->ccc_lru)); + + env = cl_env_nested_get(&nest); + if (IS_ERR(env)) + RETURN(rc); + + rc = osc_lru_shrink(env, cli, osc_cache_too_much(cli), false); + if (rc != 0) { + if (rc == -EBUSY) + rc = 0; + + CDEBUG(D_CACHE, "%s: Free %d pages from own LRU: %p.\n", + cli->cl_import->imp_obd->obd_name, rc, cli); + GOTO(out, rc); + } + + CDEBUG(D_CACHE, "%s: cli %p no free slots, pages: %d, busy: %d.\n", + cli->cl_import->imp_obd->obd_name, cli, + atomic_read(&cli->cl_lru_in_list), + atomic_read(&cli->cl_lru_busy)); + + /* Reclaim LRU slots from other client_obd as it can't free enough + * from its own. This should rarely happen. */ + spin_lock(&cache->ccc_lru_lock); + cache->ccc_lru_shrinkers++; + list_move_tail(&cli->cl_lru_osc, &cache->ccc_lru); + + max_scans = atomic_read(&cache->ccc_users); + while (--max_scans > 0 && !list_empty(&cache->ccc_lru)) { + cli = list_entry(cache->ccc_lru.next, struct client_obd, + cl_lru_osc); + + CDEBUG(D_CACHE, "%s: cli %p LRU pages: %d, busy: %d.\n", + cli->cl_import->imp_obd->obd_name, cli, + atomic_read(&cli->cl_lru_in_list), + atomic_read(&cli->cl_lru_busy)); + + list_move_tail(&cli->cl_lru_osc, &cache->ccc_lru); + if (osc_cache_too_much(cli) > 0) { + spin_unlock(&cache->ccc_lru_lock); + + rc = osc_lru_shrink(env, cli, osc_cache_too_much(cli), + true); + spin_lock(&cache->ccc_lru_lock); + if (rc != 0) + break; + } + } + spin_unlock(&cache->ccc_lru_lock); + +out: + cl_env_nested_put(&nest, env); + CDEBUG(D_CACHE, "%s: cli %p freed %d pages.\n", + cli->cl_import->imp_obd->obd_name, cli, rc); + return rc; +} + +static int osc_lru_reserve(const struct lu_env *env, struct osc_object *obj, + struct osc_page *opg) +{ + struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL); + struct osc_io *oio = osc_env_io(env); + struct client_obd *cli = osc_cli(obj); + int rc = 0; + ENTRY; - osc_page_transfer_get(opg, "transfer\0imm"); - osc_page_transfer_add(env, opg, crt); + if (cli->cl_cache == NULL) /* shall not be in LRU */ + RETURN(0); + + if (oio->oi_lru_reserved > 0) { + --oio->oi_lru_reserved; + goto out; + } + + LASSERT(atomic_read(cli->cl_lru_left) >= 0); + while (!atomic_add_unless(cli->cl_lru_left, -1, 0)) { + + /* run out of LRU spaces, try to drop some by itself */ + rc = osc_lru_reclaim(cli); + if (rc < 0) + break; + if (rc > 0) + continue; + + cond_resched(); + rc = l_wait_event(osc_lru_waitq, + atomic_read(cli->cl_lru_left) > 0, + &lwi); + if (rc < 0) + break; + } + +out: + if (rc >= 0) { + atomic_inc(&cli->cl_lru_busy); + opg->ops_in_lru = 1; + rc = 0; + } + + RETURN(rc); } /** @} osc */