X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fobdclass%2Fcl_page.c;h=5c8973f9e17f7f05d7b8e3f3ba194c282012f5a5;hp=926035e5ace1c43d0392a0e0539087ca1f81d25f;hb=c5361360e51de22a59d4427327bddf9fd398f352;hpb=84a795f90412ee575703476728f1522c06de4a2c diff --git a/lustre/obdclass/cl_page.c b/lustre/obdclass/cl_page.c index 926035e..5c8973f 100644 --- a/lustre/obdclass/cl_page.c +++ b/lustre/obdclass/cl_page.c @@ -28,6 +28,9 @@ /* * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. + * + * Copyright (c) 2011 Whamcloud, Inc. + * */ /* * This file is part of Lustre, http://www.lustre.org/ @@ -184,11 +187,12 @@ EXPORT_SYMBOL(cl_page_lookup); * * Gang tree lookup (radix_tree_gang_lookup()) optimization is absolutely * crucial in the face of [offset, EOF] locks. + * + * Return at least one page in @queue unless there is no covered page. */ -void cl_page_gang_lookup(const struct lu_env *env, struct cl_object *obj, - struct cl_io *io, pgoff_t start, pgoff_t end, - struct cl_page_list *queue, int nonblock, - int *resched) +int cl_page_gang_lookup(const struct lu_env *env, struct cl_object *obj, + struct cl_io *io, pgoff_t start, pgoff_t end, + struct cl_page_list *queue) { struct cl_object_header *hdr; struct cl_page *page; @@ -199,15 +203,10 @@ void cl_page_gang_lookup(const struct lu_env *env, struct cl_object *obj, unsigned int nr; unsigned int i; unsigned int j; - int (*page_own)(const struct lu_env *env, - struct cl_io *io, - struct cl_page *pg); + int res = CLP_GANG_OKAY; + int tree_lock = 1; ENTRY; - if (resched != NULL) - *resched = 0; - page_own = nonblock ? cl_page_own_try : cl_page_own; - idx = start; hdr = cl_object_header(obj); pvec = cl_env_info(env)->clt_pvec; @@ -215,18 +214,19 @@ void cl_page_gang_lookup(const struct lu_env *env, struct cl_object *obj, cfs_spin_lock(&hdr->coh_page_guard); while ((nr = radix_tree_gang_lookup(&hdr->coh_tree, (void **)pvec, idx, CLT_PVEC_SIZE)) > 0) { + int end_of_region = 0; idx = pvec[nr - 1]->cp_index + 1; for (i = 0, j = 0; i < nr; ++i) { page = pvec[i]; pvec[i] = NULL; - if (page->cp_index > end) + + LASSERT(page->cp_type == CPT_CACHEABLE); + if (page->cp_index > end) { + end_of_region = 1; break; + } if (page->cp_state == CPS_FREEING) continue; - if (page->cp_type == CPT_TRANSIENT) { - /* God, we found a transient page!*/ - continue; - } slice = cl_page_at_trusted(page, dtype); /* @@ -258,24 +258,44 @@ void cl_page_gang_lookup(const struct lu_env *env, struct cl_object *obj, * error in the latter case). */ cfs_spin_unlock(&hdr->coh_page_guard); + tree_lock = 0; + for (i = 0; i < j; ++i) { page = pvec[i]; - if (page_own(env, io, page) == 0) - cl_page_list_add(queue, page); + if (res == CLP_GANG_OKAY) { + typeof(cl_page_own) *page_own; + + page_own = queue->pl_nr ? + cl_page_own_try : cl_page_own; + if (page_own(env, io, page) == 0) { + cl_page_list_add(queue, page); + } else if (page->cp_state != CPS_FREEING) { + /* cl_page_own() won't fail unless + * the page is being freed. */ + LASSERT(queue->pl_nr != 0); + res = CLP_GANG_AGAIN; + } + } lu_ref_del(&page->cp_reference, "page_list", cfs_current()); cl_page_put(env, page); } - cfs_spin_lock(&hdr->coh_page_guard); - if (nr < CLT_PVEC_SIZE) + if (nr < CLT_PVEC_SIZE || end_of_region) break; - if (resched != NULL && cfs_need_resched()) { - *resched = 1; + + /* if the number of pages is zero, this will mislead the caller + * that there is no page any more. */ + if (queue->pl_nr && cfs_need_resched()) + res = CLP_GANG_RESCHED; + if (res != CLP_GANG_OKAY) break; - } + + cfs_spin_lock(&hdr->coh_page_guard); + tree_lock = 1; } - cfs_spin_unlock(&hdr->coh_page_guard); - EXIT; + if (tree_lock) + cfs_spin_unlock(&hdr->coh_page_guard); + RETURN(res); } EXPORT_SYMBOL(cl_page_gang_lookup); @@ -357,8 +377,7 @@ static int cl_page_alloc(const struct lu_env *env, struct cl_object *o, err = o->co_ops->coo_page_init(env, o, page, vmpage); if (err != NULL) { - cl_page_state_set_trust(page, - CPS_FREEING); + cl_page_delete0(env, page, 0); cl_page_free(env, page); page = err; break; @@ -398,13 +417,13 @@ static struct cl_page *cl_page_find0(const struct lu_env *env, enum cl_page_type type, struct cl_page *parent) { - struct cl_page *page; + struct cl_page *page = NULL; struct cl_page *ghost = NULL; struct cl_object_header *hdr; struct cl_site *site = cl_object_site(o); int err; - LINVRNT(type == CPT_CACHEABLE || type == CPT_TRANSIENT); + LASSERT(type == CPT_CACHEABLE || type == CPT_TRANSIENT); cfs_might_sleep(); ENTRY; @@ -431,11 +450,8 @@ static struct cl_page *cl_page_find0(const struct lu_env *env, cl_page_vmpage(env, page) == vmpage && (void *)radix_tree_lookup(&hdr->coh_tree, idx) == page)); - } else { - cfs_spin_lock(&hdr->coh_page_guard); - page = cl_page_lookup(hdr, idx); - cfs_spin_unlock(&hdr->coh_page_guard); } + if (page != NULL) { cfs_atomic_inc(&site->cs_pages.cs_hit); RETURN(page); @@ -445,6 +461,16 @@ static struct cl_page *cl_page_find0(const struct lu_env *env, err = cl_page_alloc(env, o, idx, vmpage, type, &page); if (err != 0) RETURN(page); + + if (type == CPT_TRANSIENT) { + if (parent) { + LASSERT(page->cp_parent == NULL); + page->cp_parent = parent; + parent->cp_child = page; + } + RETURN(page); + } + /* * XXX optimization: use radix_tree_preload() here, and change tree * gfp mask to GFP_KERNEL in cl_object_header_init(). @@ -467,27 +493,8 @@ static struct cl_page *cl_page_find0(const struct lu_env *env, * which is very useful during diagnosing and debugging. */ page = ERR_PTR(err); - if (err == -EEXIST) { - /* - * XXX in case of a lookup for CPT_TRANSIENT page, - * nothing protects a CPT_CACHEABLE page from being - * concurrently moved into CPS_FREEING state. - */ - page = cl_page_lookup(hdr, idx); - PASSERT(env, page, page != NULL); - if (page->cp_type == CPT_TRANSIENT && - type == CPT_CACHEABLE) { - /* XXX: We should make sure that inode sem - * keeps being held in the lifetime of - * transient pages, so it is impossible to - * have conflicting transient pages. - */ - cfs_spin_unlock(&hdr->coh_page_guard); - cl_page_put(env, page); - cfs_spin_lock(&hdr->coh_page_guard); - page = ERR_PTR(-EBUSY); - } - } + CL_PAGE_DEBUG(D_ERROR, env, ghost, + "fail to insert into radix tree: %d\n", err); } else { if (parent) { LASSERT(page->cp_parent == NULL); @@ -553,7 +560,7 @@ static inline int cl_page_invariant(const struct cl_page *pg) * Either page is early in initialization (has neither child * nor parent yet), or it is in the object radix tree. */ - ergo(pg->cp_state < CPS_FREEING, + ergo(pg->cp_state < CPS_FREEING && pg->cp_type == CPT_CACHEABLE, (void *)radix_tree_lookup(&header->coh_tree, pg->cp_index) == pg || (child == NULL && parent == NULL)); @@ -630,7 +637,6 @@ static void cl_page_state_set0(const struct lu_env *env, static void cl_page_state_set(const struct lu_env *env, struct cl_page *page, enum cl_page_state state) { - PINVRNT(env, page, cl_page_invariant(page)); cl_page_state_set0(env, page, state); } @@ -975,7 +981,7 @@ static int cl_page_own0(const struct lu_env *env, struct cl_io *io, io = cl_io_top(io); if (pg->cp_state == CPS_FREEING) { - result = -EAGAIN; + result = -ENOENT; } else { result = CL_PAGE_INVOKE(env, pg, CL_PAGE_OP(cpo_own), (const struct lu_env *, @@ -992,7 +998,7 @@ static int cl_page_own0(const struct lu_env *env, struct cl_io *io, cl_page_state_set(env, pg, CPS_OWNED); } else { cl_page_disown0(env, io, pg); - result = -EAGAIN; + result = -ENOENT; } } } @@ -1037,7 +1043,6 @@ EXPORT_SYMBOL(cl_page_own_try); void cl_page_assume(const struct lu_env *env, struct cl_io *io, struct cl_page *pg) { - PASSERT(env, pg, pg->cp_state < CPS_OWNED); PASSERT(env, pg, pg->cp_owner == NULL); PINVRNT(env, pg, cl_object_same(pg->cp_obj, io->ci_obj)); PINVRNT(env, pg, cl_page_invariant(pg)); @@ -1159,23 +1164,25 @@ static void cl_page_delete0(const struct lu_env *env, struct cl_page *pg, cl_page_export(env, pg, 0); cl_page_state_set0(env, pg, CPS_FREEING); - if (!radix) - /* - * !radix means that @pg is not yet in the radix tree, skip - * removing it. - */ - tmp = pg->cp_child; - for (; tmp != NULL; tmp = tmp->cp_child) { - void *value; - struct cl_object_header *hdr; - - hdr = cl_object_header(tmp->cp_obj); - cfs_spin_lock(&hdr->coh_page_guard); - value = radix_tree_delete(&hdr->coh_tree, tmp->cp_index); - PASSERT(env, tmp, value == tmp); - PASSERT(env, tmp, hdr->coh_pages > 0); - hdr->coh_pages--; - cfs_spin_unlock(&hdr->coh_page_guard); + if (tmp->cp_type == CPT_CACHEABLE) { + if (!radix) + /* !radix means that @pg is not yet in the radix tree, + * skip removing it. + */ + tmp = pg->cp_child; + for (; tmp != NULL; tmp = tmp->cp_child) { + void *value; + struct cl_object_header *hdr; + + hdr = cl_object_header(tmp->cp_obj); + cfs_spin_lock(&hdr->coh_page_guard); + value = radix_tree_delete(&hdr->coh_tree, + tmp->cp_index); + PASSERT(env, tmp, value == tmp); + PASSERT(env, tmp, hdr->coh_pages > 0); + hdr->coh_pages--; + cfs_spin_unlock(&hdr->coh_page_guard); + } } CL_PAGE_INVOID(env, pg, CL_PAGE_OP(cpo_delete), @@ -1354,7 +1361,6 @@ void cl_page_completion(const struct lu_env *env, /* cl_page::cp_req already cleared by the caller (osc_completion()) */ PASSERT(env, pg, pg->cp_req == NULL); PASSERT(env, pg, pg->cp_state == cl_req_type_state(crt)); - PINVRNT(env, pg, cl_page_invariant(pg)); ENTRY; CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, ioret); @@ -1368,6 +1374,7 @@ void cl_page_completion(const struct lu_env *env, (const struct lu_env *, const struct cl_page_slice *, int), ioret); if (anchor) { + LASSERT(cl_page_is_vmlocked(env, pg)); LASSERT(pg->cp_sync_io == anchor); pg->cp_sync_io = NULL; cl_sync_io_note(anchor, ioret); @@ -1478,7 +1485,6 @@ int cl_pages_prune(const struct lu_env *env, struct cl_object *clobj) struct cl_object *obj = cl_object_top(clobj); struct cl_io *io; struct cl_page_list *plist; - int resched; int result; ENTRY; @@ -1499,8 +1505,8 @@ int cl_pages_prune(const struct lu_env *env, struct cl_object *clobj) do { cl_page_list_init(plist); - cl_page_gang_lookup(env, obj, io, 0, CL_PAGE_EOF, plist, 0, - &resched); + result = cl_page_gang_lookup(env, obj, io, 0, CL_PAGE_EOF, + plist); /* * Since we're purging the pages of an object, we don't care * the possible outcomes of the following functions. @@ -1510,9 +1516,9 @@ int cl_pages_prune(const struct lu_env *env, struct cl_object *clobj) cl_page_list_disown(env, io, plist); cl_page_list_fini(env, plist); - if (resched) + if (result == CLP_GANG_RESCHED) cfs_cond_resched(); - } while (resched); + } while (result != CLP_GANG_OKAY); cl_io_fini(env, io); RETURN(result);