X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fllite%2Frw.c;h=e359b60544241cef08850ba1067733b5c8ca7253;hp=df40ae6dd0e79fb834d6f55af5555accf90efd88;hb=c084c6215851d238d14b0d414374b6b55c91f525;hpb=7b778c9476a43a3e6c80414452e93bcb50c78013 diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c index df40ae6..e359b60 100644 --- a/lustre/llite/rw.c +++ b/lustre/llite/rw.c @@ -1,6 +1,4 @@ -/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- - * vim:expandtab:shiftwidth=8:tabstop=8: - * +/* * GPL HEADER START * * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. @@ -17,17 +15,15 @@ * * You should have received a copy of the GNU General Public License * version 2 along with this program; If not, see - * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf - * - * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, - * CA 95054 USA or visit www.sun.com if you need additional information or - * have any questions. + * http://www.gnu.org/licenses/gpl-2.0.html * * GPL HEADER END */ /* - * Copyright 2008 Sun Microsystems, Inc. All rights reserved + * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. + * + * Copyright (c) 2011, 2016, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ @@ -38,16 +34,13 @@ * Lustre Lite I/O page cache routines shared by different kernel revs */ -#include #include #include #include #include #include -#include #include -#include -#include +#include #include #include @@ -55,337 +48,95 @@ #include #include #include -#include /* current_is_kswapd() */ #include #define DEBUG_SUBSYSTEM S_LLITE -//#include -#include #include #include "llite_internal.h" -#include - -/* this isn't where truncate starts. roughly: - * sys_truncate->ll_setattr_raw->vmtruncate->ll_truncate. setattr_raw grabs - * DLM lock on [size, EOF], i_mutex, ->lli_size_sem, and WRITE_I_ALLOC_SEM to - * avoid races. - * - * must be called under ->lli_size_sem */ -void ll_truncate(struct inode *inode) -{ - struct ll_inode_info *lli = ll_i2info(inode); - ENTRY; - - CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p) to %Lu\n",inode->i_ino, - inode->i_generation, inode, i_size_read(inode)); - - ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_TRUNC, 1); - if (lli->lli_size_sem_owner == cfs_current()) { - LASSERT_SEM_LOCKED(&lli->lli_size_sem); - ll_inode_size_unlock(inode, 0); - } - - EXIT; - return; -} /* ll_truncate */ - -/** - * Finalizes cl-data before exiting typical address_space operation. Dual to - * ll_cl_init(). - */ -static void ll_cl_fini(struct ll_cl_context *lcc) -{ - struct lu_env *env = lcc->lcc_env; - struct cl_io *io = lcc->lcc_io; - struct cl_page *page = lcc->lcc_page; - - LASSERT(lcc->lcc_cookie == current); - LASSERT(env != NULL); - - if (page != NULL) { - lu_ref_del(&page->cp_reference, "cl_io", io); - cl_page_put(env, page); - } - - if (io && lcc->lcc_created) { - cl_io_end(env, io); - cl_io_unlock(env, io); - cl_io_iter_fini(env, io); - cl_io_fini(env, io); - } - cl_env_put(env, &lcc->lcc_refcheck); -} - -/** - * Initializes common cl-data at the typical address_space operation entry - * point. - */ -static struct ll_cl_context *ll_cl_init(struct file *file, - struct page *vmpage, int create) -{ - struct ll_cl_context *lcc; - struct lu_env *env; - struct cl_io *io; - struct cl_object *clob; - struct ccc_io *cio; - - int refcheck; - int result = 0; - - clob = ll_i2info(vmpage->mapping->host)->lli_clob; - LASSERT(clob != NULL); - - env = cl_env_get(&refcheck); - if (IS_ERR(env)) - return ERR_PTR(PTR_ERR(env)); - - lcc = &vvp_env_info(env)->vti_io_ctx; - memset(lcc, 0, sizeof(*lcc)); - lcc->lcc_env = env; - lcc->lcc_refcheck = refcheck; - lcc->lcc_cookie = current; - - cio = ccc_env_io(env); - io = cio->cui_cl.cis_io; - if (io == NULL && create) { - struct vvp_io *vio; - loff_t pos; - - /* - * Loop-back driver calls ->prepare_write() and ->sendfile() - * methods directly, bypassing file system ->write() operation, - * so cl_io has to be created here. - */ - - io = &ccc_env_info(env)->cti_io; - vio = vvp_env_io(env); - ll_io_init(io, file, 1); - - /* No lock at all for this kind of IO - we can't do it because - * we have held page lock, it would cause deadlock. - * XXX: This causes poor performance to loop device - One page - * per RPC. - * In order to get better performance, users should use - * lloop driver instead. - */ - io->ci_lockreq = CILR_NEVER; - - pos = (vmpage->index << CFS_PAGE_SHIFT); - - /* Create a temp IO to serve write. */ - result = cl_io_rw_init(env, io, CIT_WRITE, pos, CFS_PAGE_SIZE); - if (result == 0) { - cio->cui_fd = LUSTRE_FPRIVATE(file); - cio->cui_iov = NULL; - cio->cui_nrsegs = 0; - result = cl_io_iter_init(env, io); - if (result == 0) { - result = cl_io_lock(env, io); - if (result == 0) - result = cl_io_start(env, io); - } - } else - result = io->ci_result; - lcc->lcc_created = 1; - } - - lcc->lcc_io = io; - if (io == NULL) - result = -EIO; - if (result == 0) { - struct cl_page *page; - - LASSERT(io != NULL); - LASSERT(io->ci_state == CIS_IO_GOING); - LASSERT(cio->cui_fd == LUSTRE_FPRIVATE(file)); - page = cl_page_find(env, clob, vmpage->index, vmpage, - CPT_CACHEABLE); - if (!IS_ERR(page)) { - lcc->lcc_page = page; - lu_ref_add(&page->cp_reference, "cl_io", io); - result = 0; - } else - result = PTR_ERR(page); - } - if (result) { - ll_cl_fini(lcc); - lcc = ERR_PTR(result); - } - - CDEBUG(D_VFSTRACE, "%lu@"DFID" -> %i %p %p\n", - vmpage->index, PFID(lu_object_fid(&clob->co_lu)), result, - env, io); - return lcc; -} - -static struct ll_cl_context *ll_cl_get(void) -{ - struct ll_cl_context *lcc; - struct lu_env *env; - int refcheck; - - env = cl_env_get(&refcheck); - LASSERT(!IS_ERR(env)); - lcc = &vvp_env_info(env)->vti_io_ctx; - LASSERT(env == lcc->lcc_env); - LASSERT(current == lcc->lcc_cookie); - cl_env_put(env, &refcheck); - - /* env has got in ll_cl_init, so it is still usable. */ - return lcc; -} - -/** - * ->prepare_write() address space operation called by generic_file_write() - * for every page during write. - */ -int ll_prepare_write(struct file *file, struct page *vmpage, unsigned from, - unsigned to) -{ - struct ll_cl_context *lcc; - int result; - ENTRY; - - lcc = ll_cl_init(file, vmpage, 1); - if (!IS_ERR(lcc)) { - struct lu_env *env = lcc->lcc_env; - struct cl_io *io = lcc->lcc_io; - struct cl_page *page = lcc->lcc_page; - - cl_page_assume(env, io, page); - if (cl_io_is_append(io)) { - struct cl_object *obj = io->ci_obj; - struct inode *inode = ccc_object_inode(obj); - /** - * In VFS file->page write loop, for appending, the - * write offset might be reset according to the new - * file size before holding i_mutex. So crw_pos should - * be reset here. BUG:17711. - */ - io->u.ci_wr.wr.crw_pos = i_size_read(inode); - } - result = cl_io_prepare_write(env, io, page, from, to); - if (result == 0) { - /* - * Add a reference, so that page is not evicted from - * the cache until ->commit_write() is called. - */ - cl_page_get(page); - lu_ref_add(&page->cp_reference, "prepare_write", - cfs_current()); - } else { - cl_page_unassume(env, io, page); - ll_cl_fini(lcc); - } - /* returning 0 in prepare assumes commit must be called - * afterwards */ - } else { - result = PTR_ERR(lcc); - } - RETURN(result); -} - -int ll_commit_write(struct file *file, struct page *vmpage, unsigned from, - unsigned to) -{ - struct ll_cl_context *lcc; - struct lu_env *env; - struct cl_io *io; - struct cl_page *page; - int result; - ENTRY; - - lcc = ll_cl_get(); - env = lcc->lcc_env; - page = lcc->lcc_page; - io = lcc->lcc_io; - - LASSERT(cl_page_is_owned(page, io)); - result = cl_io_commit_write(env, io, page, from, to); - if (cl_page_is_owned(page, io)) - cl_page_unassume(env, io, page); - /* - * Release reference acquired by cl_io_prepare_write(). - */ - lu_ref_del(&page->cp_reference, "prepare_write", cfs_current()); - cl_page_put(env, page); - ll_cl_fini(lcc); - RETURN(result); -} - -struct obd_capa *cl_capa_lookup(struct inode *inode, enum cl_req_type crt) -{ - __u64 opc; - - opc = crt == CRT_WRITE ? CAPA_OPC_OSS_WRITE : CAPA_OPC_OSS_RW; - return ll_osscapa_get(inode, opc); -} +#include static void ll_ra_stats_inc_sbi(struct ll_sb_info *sbi, enum ra_stat which); -/* WARNING: This algorithm is used to reduce the contention on - * sbi->ll_lock. It should work well if the ra_max_pages is much - * greater than the single file's read-ahead window. +/** + * Get readahead pages from the filesystem readahead pool of the client for a + * thread. * - * TODO: There may exist a `global sync problem' in this implementation. - * Considering the global ra window is 100M, and each file's ra window is 10M, - * there are over 10 files trying to get its ra budget and reach - * ll_ra_count_get at the exactly same time. All of them will get a zero ra - * window, although the global window is 100M. -jay - */ -static unsigned long ll_ra_count_get(struct ll_sb_info *sbi, unsigned long len) + * /param sbi superblock for filesystem readahead state ll_ra_info + * /param ria per-thread readahead state + * /param pages number of pages requested for readahead for the thread. + * + * WARNING: This algorithm is used to reduce contention on sbi->ll_lock. + * It should work well if the ra_max_pages is much greater than the single + * file's read-ahead window, and not too many threads contending for + * these readahead pages. + * + * TODO: There may be a 'global sync problem' if many threads are trying + * to get an ra budget that is larger than the remaining readahead pages + * and reach here at exactly the same time. They will compute /a ret to + * consume the remaining pages, but will fail at atomic_add_return() and + * get a zero ra window, although there is still ra space remaining. - Jay */ + +static unsigned long ll_ra_count_get(struct ll_sb_info *sbi, + struct ra_io_arg *ria, + unsigned long pages, unsigned long min) { struct ll_ra_info *ra = &sbi->ll_ra_info; - unsigned long ret; + long ret; ENTRY; - /** - * If read-ahead pages left are less than 1M, do not do read-ahead, + /* If read-ahead pages left are less than 1M, do not do read-ahead, * otherwise it will form small read RPC(< 1M), which hurt server - * performance a lot. - */ - ret = min(ra->ra_max_pages - cfs_atomic_read(&ra->ra_cur_pages), len); - if ((int)ret < 0 || ret < min((unsigned long)PTLRPC_MAX_BRW_PAGES, len)) + * performance a lot. */ + ret = min(ra->ra_max_pages - atomic_read(&ra->ra_cur_pages), + pages); + if (ret < 0 || ret < min_t(long, PTLRPC_MAX_BRW_PAGES, pages)) GOTO(out, ret = 0); - if (cfs_atomic_add_return(ret, &ra->ra_cur_pages) > ra->ra_max_pages) { - cfs_atomic_sub(ret, &ra->ra_cur_pages); - ret = 0; - } + if (atomic_add_return(ret, &ra->ra_cur_pages) > ra->ra_max_pages) { + atomic_sub(ret, &ra->ra_cur_pages); + ret = 0; + } + out: - RETURN(ret); + if (ret < min) { + /* override ra limit for maximum performance */ + atomic_add(min - ret, &ra->ra_cur_pages); + ret = min; + } + RETURN(ret); } void ll_ra_count_put(struct ll_sb_info *sbi, unsigned long len) { - struct ll_ra_info *ra = &sbi->ll_ra_info; - cfs_atomic_sub(len, &ra->ra_cur_pages); + struct ll_ra_info *ra = &sbi->ll_ra_info; + atomic_sub(len, &ra->ra_cur_pages); } static void ll_ra_stats_inc_sbi(struct ll_sb_info *sbi, enum ra_stat which) { - LASSERTF(which >= 0 && which < _NR_RA_STAT, "which: %u\n", which); - lprocfs_counter_incr(sbi->ll_ra_stats, which); + LASSERTF(which < _NR_RA_STAT, "which: %u\n", which); + lprocfs_counter_incr(sbi->ll_ra_stats, which); } -void ll_ra_stats_inc(struct address_space *mapping, enum ra_stat which) +void ll_ra_stats_inc(struct inode *inode, enum ra_stat which) { - struct ll_sb_info *sbi = ll_i2sbi(mapping->host); - ll_ra_stats_inc_sbi(sbi, which); + struct ll_sb_info *sbi = ll_i2sbi(inode); + ll_ra_stats_inc_sbi(sbi, which); } #define RAS_CDEBUG(ras) \ - CDEBUG(D_READA, \ - "lrp %lu cr %lu cp %lu ws %lu wl %lu nra %lu r %lu ri %lu" \ - "csr %lu sf %lu sp %lu sl %lu \n", \ - ras->ras_last_readpage, ras->ras_consecutive_requests, \ - ras->ras_consecutive_pages, ras->ras_window_start, \ - ras->ras_window_len, ras->ras_next_readahead, \ - ras->ras_requests, ras->ras_request_index, \ - ras->ras_consecutive_stride_requests, ras->ras_stride_offset, \ - ras->ras_stride_pages, ras->ras_stride_length) + CDEBUG(D_READA, \ + "lrp %lu cr %lu cp %lu ws %lu wl %lu nra %lu rpc %lu " \ + "r %lu ri %lu csr %lu sf %lu sp %lu sl %lu\n", \ + ras->ras_last_readpage, ras->ras_consecutive_requests, \ + ras->ras_consecutive_pages, ras->ras_window_start, \ + ras->ras_window_len, ras->ras_next_readahead, \ + ras->ras_rpc_size, \ + ras->ras_requests, ras->ras_request_index, \ + ras->ras_consecutive_stride_requests, ras->ras_stride_offset, \ + ras->ras_stride_pages, ras->ras_stride_length) static int index_in_window(unsigned long index, unsigned long point, unsigned long before, unsigned long after) @@ -400,158 +151,91 @@ static int index_in_window(unsigned long index, unsigned long point, return start <= index && index <= end; } -static struct ll_readahead_state *ll_ras_get(struct file *f) -{ - struct ll_file_data *fd; - - fd = LUSTRE_FPRIVATE(f); - return &fd->fd_ras; -} - -void ll_ra_read_in(struct file *f, struct ll_ra_read *rar) -{ - struct ll_readahead_state *ras; - - ras = ll_ras_get(f); - - cfs_spin_lock(&ras->ras_lock); - ras->ras_requests++; - ras->ras_request_index = 0; - ras->ras_consecutive_requests++; - rar->lrr_reader = current; - - cfs_list_add(&rar->lrr_linkage, &ras->ras_read_beads); - cfs_spin_unlock(&ras->ras_lock); -} - -void ll_ra_read_ex(struct file *f, struct ll_ra_read *rar) -{ - struct ll_readahead_state *ras; - - ras = ll_ras_get(f); - - cfs_spin_lock(&ras->ras_lock); - cfs_list_del_init(&rar->lrr_linkage); - cfs_spin_unlock(&ras->ras_lock); -} - -static struct ll_ra_read *ll_ra_read_get_locked(struct ll_readahead_state *ras) -{ - struct ll_ra_read *scan; - - cfs_list_for_each_entry(scan, &ras->ras_read_beads, lrr_linkage) { - if (scan->lrr_reader == current) - return scan; - } - return NULL; -} - -struct ll_ra_read *ll_ra_read_get(struct file *f) -{ - struct ll_readahead_state *ras; - struct ll_ra_read *bead; - - ras = ll_ras_get(f); - - cfs_spin_lock(&ras->ras_lock); - bead = ll_ra_read_get_locked(ras); - cfs_spin_unlock(&ras->ras_lock); - return bead; -} - -static int cl_read_ahead_page(const struct lu_env *env, struct cl_io *io, - struct cl_page_list *queue, struct cl_page *page, - struct page *vmpage) +void ll_ras_enter(struct file *f) { - struct ccc_page *cp; - int rc; - - ENTRY; - - rc = 0; - cl_page_assume(env, io, page); - lu_ref_add(&page->cp_reference, "ra", cfs_current()); - cp = cl2ccc_page(cl_page_at(page, &vvp_device_type)); - if (!cp->cpg_defer_uptodate && !Page_Uptodate(vmpage)) { - rc = cl_page_is_under_lock(env, io, page); - if (rc == -EBUSY) { - cp->cpg_defer_uptodate = 1; - cp->cpg_ra_used = 0; - cl_page_list_add(queue, page); - rc = 1; - } else { - cl_page_delete(env, page); - rc = -ENOLCK; - } - } else - /* skip completed pages */ - cl_page_unassume(env, io, page); - lu_ref_del(&page->cp_reference, "ra", cfs_current()); - cl_page_put(env, page); - RETURN(rc); + struct ll_file_data *fd = LUSTRE_FPRIVATE(f); + struct ll_readahead_state *ras = &fd->fd_ras; + + spin_lock(&ras->ras_lock); + ras->ras_requests++; + ras->ras_request_index = 0; + ras->ras_consecutive_requests++; + spin_unlock(&ras->ras_lock); } /** * Initiates read-ahead of a page with given index. * - * \retval +ve: page was added to \a queue. - * - * \retval -ENOLCK: there is no extent lock for this part of a file, stop - * read-ahead. - * - * \retval -ve, 0: page wasn't added to \a queue for other reason. + * \retval +ve: page was already uptodate so it will be skipped + * from being added; + * \retval -ve: page wasn't added to \a queue for error; + * \retval 0: page was added into \a queue for read ahead. */ static int ll_read_ahead_page(const struct lu_env *env, struct cl_io *io, - struct cl_page_list *queue, - int index, struct address_space *mapping) + struct cl_page_list *queue, pgoff_t index) { - struct page *vmpage; - struct cl_object *clob = ll_i2info(mapping->host)->lli_clob; - struct cl_page *page; - enum ra_stat which = _NR_RA_STAT; /* keep gcc happy */ - unsigned int gfp_mask; - int rc = 0; - const char *msg = NULL; - - ENTRY; + struct cl_object *clob = io->ci_obj; + struct inode *inode = vvp_object_inode(clob); + struct page *vmpage; + struct cl_page *page; + struct vvp_page *vpg; + enum ra_stat which = _NR_RA_STAT; /* keep gcc happy */ + int rc = 0; + const char *msg = NULL; + ENTRY; + + vmpage = grab_cache_page_nowait(inode->i_mapping, index); + if (vmpage == NULL) { + which = RA_STAT_FAILED_GRAB_PAGE; + msg = "g_c_p_n failed"; + GOTO(out, rc = -EBUSY); + } + + /* Check if vmpage was truncated or reclaimed */ + if (vmpage->mapping != inode->i_mapping) { + which = RA_STAT_WRONG_GRAB_PAGE; + msg = "g_c_p_n returned invalid page"; + GOTO(out, rc = -EBUSY); + } + + page = cl_page_find(env, clob, vmpage->index, vmpage, CPT_CACHEABLE); + if (IS_ERR(page)) { + which = RA_STAT_FAILED_GRAB_PAGE; + msg = "cl_page_find failed"; + GOTO(out, rc = PTR_ERR(page)); + } + + lu_ref_add(&page->cp_reference, "ra", current); + cl_page_assume(env, io, page); + vpg = cl2vvp_page(cl_object_page_slice(clob, page)); + if (!vpg->vpg_defer_uptodate && !PageUptodate(vmpage)) { + vpg->vpg_defer_uptodate = 1; + vpg->vpg_ra_used = 0; + cl_page_list_add(queue, page); + } else { + /* skip completed pages */ + cl_page_unassume(env, io, page); + /* This page is already uptodate, returning a positive number + * to tell the callers about this */ + rc = 1; + } + + lu_ref_del(&page->cp_reference, "ra", current); + cl_page_put(env, page); - gfp_mask = GFP_HIGHUSER & ~__GFP_WAIT; -#ifdef __GFP_NOWARN - gfp_mask |= __GFP_NOWARN; -#endif - vmpage = grab_cache_page_nowait_gfp(mapping, index, gfp_mask); - if (vmpage != NULL) { - /* Check if vmpage was truncated or reclaimed */ - if (vmpage->mapping == mapping) { - page = cl_page_find(env, clob, vmpage->index, - vmpage, CPT_CACHEABLE); - if (!IS_ERR(page)) { - rc = cl_read_ahead_page(env, io, queue, - page, vmpage); - if (rc == -ENOLCK) { - which = RA_STAT_FAILED_MATCH; - msg = "lock match failed"; - } - } else { - which = RA_STAT_FAILED_GRAB_PAGE; - msg = "cl_page_find failed"; - } - } else { - which = RA_STAT_WRONG_GRAB_PAGE; - msg = "g_c_p_n returned invalid page"; - } - if (rc != 1) - unlock_page(vmpage); - page_cache_release(vmpage); - } else { - which = RA_STAT_FAILED_GRAB_PAGE; - msg = "g_c_p_n failed"; - } - if (msg != NULL) { - ll_ra_stats_inc(mapping, which); - CDEBUG(D_READA, "%s\n", msg); - } - RETURN(rc); +out: + if (vmpage != NULL) { + if (rc != 0) + unlock_page(vmpage); + put_page(vmpage); + } + if (msg != NULL) { + ll_ra_stats_inc(inode, which); + CDEBUG(D_READA, "%s\n", msg); + + } + + RETURN(rc); } #define RIA_DEBUG(ria) \ @@ -559,12 +243,11 @@ static int ll_read_ahead_page(const struct lu_env *env, struct cl_io *io, ria->ria_start, ria->ria_end, ria->ria_stoff, ria->ria_length,\ ria->ria_pages) -#define RAS_INCREASE_STEP PTLRPC_MAX_BRW_PAGES - static inline int stride_io_mode(struct ll_readahead_state *ras) { return ras->ras_consecutive_stride_requests > 1; } + /* The function calculates how much pages will be read in * [off, off + length], in such stride IO area, * stride_offset = st_off, stride_lengh = st_len, @@ -587,8 +270,8 @@ static unsigned long stride_pg_count(pgoff_t st_off, unsigned long st_len, unsigned long st_pgs, unsigned long off, unsigned long length) { - unsigned long start = off > st_off ? off - st_off : 0; - unsigned long end = off + length > st_off ? off + length - st_off : 0; + __u64 start = off > st_off ? off - st_off : 0; + __u64 end = off + length > st_off ? off + length - st_off : 0; unsigned long start_left = 0; unsigned long end_left = 0; unsigned long pg_count; @@ -606,7 +289,7 @@ stride_pg_count(pgoff_t st_off, unsigned long st_len, unsigned long st_pgs, if (end_left > st_pgs) end_left = st_pgs; - CDEBUG(D_READA, "start %lu, end %lu start_left %lu end_left %lu \n", + CDEBUG(D_READA, "start %llu, end %llu start_left %lu end_left %lu\n", start, end, start_left, end_left); if (start == end) @@ -630,6 +313,16 @@ static int ria_page_count(struct ra_io_arg *ria) length); } +static unsigned long ras_align(struct ll_readahead_state *ras, + unsigned long index, + unsigned long *remainder) +{ + unsigned long rem = index % ras->ras_rpc_size; + if (remainder != NULL) + *remainder = rem; + return index - rem; +} + /*Check whether the index is in the defined ra-window */ static int ras_inside_ra_window(unsigned long idx, struct ra_io_arg *ria) { @@ -638,34 +331,67 @@ static int ras_inside_ra_window(unsigned long idx, struct ra_io_arg *ria) * For stride I/O mode, just check whether the idx is inside * the ria_pages. */ return ria->ria_length == 0 || ria->ria_length == ria->ria_pages || - (idx - ria->ria_stoff) % ria->ria_length < ria->ria_pages; + (idx >= ria->ria_stoff && (idx - ria->ria_stoff) % + ria->ria_length < ria->ria_pages); } -static int ll_read_ahead_pages(const struct lu_env *env, - struct cl_io *io, struct cl_page_list *queue, - struct ra_io_arg *ria, - unsigned long *reserved_pages, - struct address_space *mapping, - unsigned long *ra_end) +static unsigned long +ll_read_ahead_pages(const struct lu_env *env, struct cl_io *io, + struct cl_page_list *queue, struct ll_readahead_state *ras, + struct ra_io_arg *ria) { - int rc, count = 0, stride_ria; - unsigned long page_idx; - - LASSERT(ria != NULL); - RIA_DEBUG(ria); - - stride_ria = ria->ria_length > ria->ria_pages && ria->ria_pages > 0; - for (page_idx = ria->ria_start; page_idx <= ria->ria_end && - *reserved_pages > 0; page_idx++) { - if (ras_inside_ra_window(page_idx, ria)) { - /* If the page is inside the read-ahead window*/ - rc = ll_read_ahead_page(env, io, queue, - page_idx, mapping); - if (rc == 1) { - (*reserved_pages)--; - count ++; - } else if (rc == -ENOLCK) - break; + struct cl_read_ahead ra = { 0 }; + int rc = 0; + bool stride_ria; + unsigned long ra_end = 0; + pgoff_t page_idx; + + LASSERT(ria != NULL); + RIA_DEBUG(ria); + + stride_ria = ria->ria_length > ria->ria_pages && ria->ria_pages > 0; + for (page_idx = ria->ria_start; + page_idx <= ria->ria_end && ria->ria_reserved > 0; page_idx++) { + if (ras_inside_ra_window(page_idx, ria)) { + if (ra.cra_end == 0 || ra.cra_end < page_idx) { + unsigned long end; + + cl_read_ahead_release(env, &ra); + + rc = cl_io_read_ahead(env, io, page_idx, &ra); + if (rc < 0) + break; + + CDEBUG(D_READA, "idx: %lu, ra: %lu, rpc: %lu\n", + page_idx, ra.cra_end, ra.cra_rpc_size); + LASSERTF(ra.cra_end >= page_idx, + "object: %p, indcies %lu / %lu\n", + io->ci_obj, ra.cra_end, page_idx); + /* update read ahead RPC size. + * NB: it's racy but doesn't matter */ + if (ras->ras_rpc_size > ra.cra_rpc_size && + ra.cra_rpc_size > 0) + ras->ras_rpc_size = ra.cra_rpc_size; + /* trim it to align with optimal RPC size */ + end = ras_align(ras, ria->ria_end + 1, NULL); + if (end > 0 && !ria->ria_eof) + ria->ria_end = end - 1; + if (ria->ria_end < ria->ria_end_min) + ria->ria_end = ria->ria_end_min; + if (ria->ria_end > ra.cra_end) + ria->ria_end = ra.cra_end; + } + if (page_idx > ria->ria_end) + break; + + /* If the page is inside the read-ahead window */ + rc = ll_read_ahead_page(env, io, queue, page_idx); + if (rc < 0) + break; + + ra_end = page_idx; + if (rc == 0) + ria->ria_reserved--; } else if (stride_ria) { /* If it is not in the read-ahead window, and it is * read-ahead mode, then check whether it should skip @@ -674,10 +400,11 @@ static int ll_read_ahead_pages(const struct lu_env *env, /* FIXME: This assertion only is valid when it is for * forward read-ahead, it will be fixed when backward * read-ahead is implemented */ - LASSERTF(page_idx > ria->ria_stoff, "Invalid page_idx %lu" - "rs %lu re %lu ro %lu rl %lu rp %lu\n", page_idx, - ria->ria_start, ria->ria_end, ria->ria_stoff, - ria->ria_length, ria->ria_pages); + LASSERTF(page_idx >= ria->ria_stoff, + "Invalid page_idx %lu rs %lu re %lu ro %lu " + "rl %lu rp %lu\n", page_idx, + ria->ria_start, ria->ria_end, ria->ria_stoff, + ria->ria_length, ria->ria_pages); offset = page_idx - ria->ria_stoff; offset = offset % (ria->ria_length); if (offset > ria->ria_pages) { @@ -688,75 +415,79 @@ static int ll_read_ahead_pages(const struct lu_env *env, } } } - *ra_end = page_idx; - return count; -} -int ll_readahead(const struct lu_env *env, struct cl_io *io, - struct ll_readahead_state *ras, struct address_space *mapping, - struct cl_page_list *queue, int flags) -{ - struct vvp_io *vio = vvp_env_io(env); - struct vvp_thread_info *vti = vvp_env_info(env); - struct cl_attr *attr = ccc_env_thread_attr(env); - unsigned long start = 0, end = 0, reserved; - unsigned long ra_end, len; - struct inode *inode; - struct ll_ra_read *bead; - struct ra_io_arg *ria = &vti->vti_ria; - struct ll_inode_info *lli; - struct cl_object *clob; - int ret = 0; - __u64 kms; - ENTRY; + cl_read_ahead_release(env, &ra); - inode = mapping->host; - lli = ll_i2info(inode); - clob = lli->lli_clob; - - memset(ria, 0, sizeof *ria); - - cl_object_attr_lock(clob); - ret = cl_object_attr_get(env, clob, attr); - cl_object_attr_unlock(clob); - - if (ret != 0) - RETURN(ret); - kms = attr->cat_kms; - if (kms == 0) { - ll_ra_stats_inc(mapping, RA_STAT_ZERO_LEN); - RETURN(0); - } + return ra_end; +} - cfs_spin_lock(&ras->ras_lock); - if (vio->cui_ra_window_set) - bead = &vio->cui_bead; - else - bead = NULL; +static int ll_readahead(const struct lu_env *env, struct cl_io *io, + struct cl_page_list *queue, + struct ll_readahead_state *ras, bool hit) +{ + struct vvp_io *vio = vvp_env_io(env); + struct ll_thread_info *lti = ll_env_info(env); + struct cl_attr *attr = vvp_env_thread_attr(env); + unsigned long len, mlen = 0; + pgoff_t ra_end, start = 0, end = 0; + struct inode *inode; + struct ra_io_arg *ria = <i->lti_ria; + struct cl_object *clob; + int ret = 0; + __u64 kms; + ENTRY; + + clob = io->ci_obj; + inode = vvp_object_inode(clob); + + memset(ria, 0, sizeof *ria); + + cl_object_attr_lock(clob); + ret = cl_object_attr_get(env, clob, attr); + cl_object_attr_unlock(clob); + + if (ret != 0) + RETURN(ret); + kms = attr->cat_kms; + if (kms == 0) { + ll_ra_stats_inc(inode, RA_STAT_ZERO_LEN); + RETURN(0); + } + + spin_lock(&ras->ras_lock); + + /** + * Note: other thread might rollback the ras_next_readahead, + * if it can not get the full size of prepared pages, see the + * end of this function. For stride read ahead, it needs to + * make sure the offset is no less than ras_stride_offset, + * so that stride read ahead can work correctly. + */ + if (stride_io_mode(ras)) + start = max(ras->ras_next_readahead, ras->ras_stride_offset); + else + start = ras->ras_next_readahead; + + if (ras->ras_window_len > 0) + end = ras->ras_window_start + ras->ras_window_len - 1; + + /* Enlarge the RA window to encompass the full read */ + if (vio->vui_ra_valid && + end < vio->vui_ra_start + vio->vui_ra_count - 1) + end = vio->vui_ra_start + vio->vui_ra_count - 1; - /* Enlarge the RA window to encompass the full read */ - if (bead != NULL && ras->ras_window_start + ras->ras_window_len < - bead->lrr_start + bead->lrr_count) { - ras->ras_window_len = bead->lrr_start + bead->lrr_count - - ras->ras_window_start; - } - /* Reserve a part of the read-ahead window that we'll be issuing */ - if (ras->ras_window_len) { - start = ras->ras_next_readahead; - end = ras->ras_window_start + ras->ras_window_len - 1; - } if (end != 0) { - unsigned long tmp_end; - /* Align RA window to optimal RPC boundary */ - tmp_end = ((end + 1) & (~(PTLRPC_MAX_BRW_PAGES - 1))) - 1; - if (tmp_end > start) - end = tmp_end; + unsigned long end_index; - /* Truncate RA window to end of file */ - end = min(end, (unsigned long)((kms - 1) >> CFS_PAGE_SHIFT)); + /* Truncate RA window to end of file */ + end_index = (unsigned long)((kms - 1) >> PAGE_SHIFT); + if (end_index <= end) { + end = end_index; + ria->ria_eof = true; + } - ras->ras_next_readahead = max(end, end + 1); - RAS_CDEBUG(ras); + ras->ras_next_readahead = max(end, end + 1); + RAS_CDEBUG(ras); } ria->ria_start = start; ria->ria_end = end; @@ -766,71 +497,96 @@ int ll_readahead(const struct lu_env *env, struct cl_io *io, ria->ria_length = ras->ras_stride_length; ria->ria_pages = ras->ras_stride_pages; } - cfs_spin_unlock(&ras->ras_lock); - - if (end == 0) { - ll_ra_stats_inc(mapping, RA_STAT_ZERO_WINDOW); - RETURN(0); - } - len = ria_page_count(ria); - if (len == 0) - RETURN(0); - - reserved = ll_ra_count_get(ll_i2sbi(inode), len); - - if (reserved < len) - ll_ra_stats_inc(mapping, RA_STAT_MAX_IN_FLIGHT); - - CDEBUG(D_READA, "reserved page %lu \n", reserved); - - ret = ll_read_ahead_pages(env, io, queue, - ria, &reserved, mapping, &ra_end); - - LASSERTF(reserved >= 0, "reserved %lu\n", reserved); - if (reserved != 0) - ll_ra_count_put(ll_i2sbi(inode), reserved); - - if (ra_end == end + 1 && ra_end == (kms >> CFS_PAGE_SHIFT)) - ll_ra_stats_inc(mapping, RA_STAT_EOF); - - /* if we didn't get to the end of the region we reserved from - * the ras we need to go back and update the ras so that the - * next read-ahead tries from where we left off. we only do so - * if the region we failed to issue read-ahead on is still ahead - * of the app and behind the next index to start read-ahead from */ - CDEBUG(D_READA, "ra_end %lu end %lu stride end %lu \n", - ra_end, end, ria->ria_end); - - if (ra_end != end + 1) { - cfs_spin_lock(&ras->ras_lock); - if (ra_end < ras->ras_next_readahead && - index_in_window(ra_end, ras->ras_window_start, 0, - ras->ras_window_len)) { - ras->ras_next_readahead = ra_end; - RAS_CDEBUG(ras); - } - cfs_spin_unlock(&ras->ras_lock); - } - - RETURN(ret); + spin_unlock(&ras->ras_lock); + + if (end == 0) { + ll_ra_stats_inc(inode, RA_STAT_ZERO_WINDOW); + RETURN(0); + } + len = ria_page_count(ria); + if (len == 0) { + ll_ra_stats_inc(inode, RA_STAT_ZERO_WINDOW); + RETURN(0); + } + + CDEBUG(D_READA, DFID": ria: %lu/%lu, bead: %lu/%lu, hit: %d\n", + PFID(lu_object_fid(&clob->co_lu)), + ria->ria_start, ria->ria_end, + vio->vui_ra_valid ? vio->vui_ra_start : 0, + vio->vui_ra_valid ? vio->vui_ra_count : 0, + hit); + + /* at least to extend the readahead window to cover current read */ + if (!hit && vio->vui_ra_valid && + vio->vui_ra_start + vio->vui_ra_count > ria->ria_start) { + unsigned long remainder; + + /* to the end of current read window. */ + mlen = vio->vui_ra_start + vio->vui_ra_count - ria->ria_start; + /* trim to RPC boundary */ + ras_align(ras, ria->ria_start, &remainder); + mlen = min(mlen, ras->ras_rpc_size - remainder); + ria->ria_end_min = ria->ria_start + mlen; + } + + ria->ria_reserved = ll_ra_count_get(ll_i2sbi(inode), ria, len, mlen); + if (ria->ria_reserved < len) + ll_ra_stats_inc(inode, RA_STAT_MAX_IN_FLIGHT); + + CDEBUG(D_READA, "reserved pages: %lu/%lu/%lu, ra_cur %d, ra_max %lu\n", + ria->ria_reserved, len, mlen, + atomic_read(&ll_i2sbi(inode)->ll_ra_info.ra_cur_pages), + ll_i2sbi(inode)->ll_ra_info.ra_max_pages); + + ra_end = ll_read_ahead_pages(env, io, queue, ras, ria); + + if (ria->ria_reserved != 0) + ll_ra_count_put(ll_i2sbi(inode), ria->ria_reserved); + + if (ra_end == end && ra_end == (kms >> PAGE_SHIFT)) + ll_ra_stats_inc(inode, RA_STAT_EOF); + + /* if we didn't get to the end of the region we reserved from + * the ras we need to go back and update the ras so that the + * next read-ahead tries from where we left off. we only do so + * if the region we failed to issue read-ahead on is still ahead + * of the app and behind the next index to start read-ahead from */ + CDEBUG(D_READA, "ra_end = %lu end = %lu stride end = %lu pages = %d\n", + ra_end, end, ria->ria_end, ret); + + if (ra_end > 0 && ra_end != end) { + ll_ra_stats_inc(inode, RA_STAT_FAILED_REACH_END); + spin_lock(&ras->ras_lock); + if (ra_end <= ras->ras_next_readahead && + index_in_window(ra_end, ras->ras_window_start, 0, + ras->ras_window_len)) { + ras->ras_next_readahead = ra_end + 1; + RAS_CDEBUG(ras); + } + spin_unlock(&ras->ras_lock); + } + + RETURN(ret); } -static void ras_set_start(struct ll_readahead_state *ras, unsigned long index) +static void ras_set_start(struct inode *inode, struct ll_readahead_state *ras, + unsigned long index) { - ras->ras_window_start = index & (~(RAS_INCREASE_STEP - 1)); + ras->ras_window_start = ras_align(ras, index, NULL); } /* called with the ras_lock held or from places where it doesn't matter */ -static void ras_reset(struct ll_readahead_state *ras, unsigned long index) +static void ras_reset(struct inode *inode, struct ll_readahead_state *ras, + unsigned long index) { - ras->ras_last_readpage = index; - ras->ras_consecutive_requests = 0; - ras->ras_consecutive_pages = 0; - ras->ras_window_len = 0; - ras_set_start(ras, index); - ras->ras_next_readahead = max(ras->ras_window_start, index); - - RAS_CDEBUG(ras); + ras->ras_last_readpage = index; + ras->ras_consecutive_requests = 0; + ras->ras_consecutive_pages = 0; + ras->ras_window_len = 0; + ras_set_start(inode, ras, index); + ras->ras_next_readahead = max(ras->ras_window_start, index + 1); + + RAS_CDEBUG(ras); } /* called with the ras_lock held or from places where it doesn't matter */ @@ -844,33 +600,34 @@ static void ras_stride_reset(struct ll_readahead_state *ras) void ll_readahead_init(struct inode *inode, struct ll_readahead_state *ras) { - cfs_spin_lock_init(&ras->ras_lock); - ras_reset(ras, 0); - ras->ras_requests = 0; - CFS_INIT_LIST_HEAD(&ras->ras_read_beads); + spin_lock_init(&ras->ras_lock); + ras->ras_rpc_size = PTLRPC_MAX_BRW_PAGES; + ras_reset(inode, ras, 0); + ras->ras_requests = 0; } /* * Check whether the read request is in the stride window. * If it is in the stride window, return 1, otherwise return 0. */ -static int index_in_stride_window(unsigned long index, - struct ll_readahead_state *ras, - struct inode *inode) +static int index_in_stride_window(struct ll_readahead_state *ras, + unsigned long index) { - unsigned long stride_gap = index - ras->ras_last_readpage - 1; + unsigned long stride_gap; + + if (ras->ras_stride_length == 0 || ras->ras_stride_pages == 0 || + ras->ras_stride_pages == ras->ras_stride_length) + return 0; - if (ras->ras_stride_length == 0 || ras->ras_stride_pages == 0 || - ras->ras_stride_pages == ras->ras_stride_length) - return 0; + stride_gap = index - ras->ras_last_readpage - 1; - /* If it is contiguous read */ - if (stride_gap == 0) - return ras->ras_consecutive_pages + 1 <= ras->ras_stride_pages; + /* If it is contiguous read */ + if (stride_gap == 0) + return ras->ras_consecutive_pages + 1 <= ras->ras_stride_pages; - /*Otherwise check the stride by itself */ - return (ras->ras_stride_length - ras->ras_stride_pages) == stride_gap && - ras->ras_consecutive_pages == ras->ras_stride_pages; + /* Otherwise check the stride by itself */ + return (ras->ras_stride_length - ras->ras_stride_pages) == stride_gap && + ras->ras_consecutive_pages == ras->ras_stride_pages; } static void ras_update_stride_detector(struct ll_readahead_state *ras, @@ -946,32 +703,39 @@ static void ras_stride_increase_window(struct ll_readahead_state *ras, RAS_CDEBUG(ras); } -static void ras_increase_window(struct ll_readahead_state *ras, - struct ll_ra_info *ra, struct inode *inode) +static void ras_increase_window(struct inode *inode, + struct ll_readahead_state *ras, + struct ll_ra_info *ra) { - /* The stretch of ra-window should be aligned with max rpc_size - * but current clio architecture does not support retrieve such - * information from lower layer. FIXME later - */ - if (stride_io_mode(ras)) - ras_stride_increase_window(ras, ra, RAS_INCREASE_STEP); - else - ras->ras_window_len = min(ras->ras_window_len + - RAS_INCREASE_STEP, - ra->ra_max_pages_per_file); + /* The stretch of ra-window should be aligned with max rpc_size + * but current clio architecture does not support retrieve such + * information from lower layer. FIXME later + */ + if (stride_io_mode(ras)) { + ras_stride_increase_window(ras, ra, ras->ras_rpc_size); + } else { + unsigned long wlen; + + wlen = min(ras->ras_window_len + ras->ras_rpc_size, + ra->ra_max_pages_per_file); + ras->ras_window_len = ras_align(ras, wlen, NULL); + } } -void ras_update(struct ll_sb_info *sbi, struct inode *inode, - struct ll_readahead_state *ras, unsigned long index, - unsigned hit) +static void ras_update(struct ll_sb_info *sbi, struct inode *inode, + struct ll_readahead_state *ras, unsigned long index, + enum ras_update_flags flags) { - struct ll_ra_info *ra = &sbi->ll_ra_info; - int zero = 0, stride_detect = 0, ra_miss = 0; - ENTRY; + struct ll_ra_info *ra = &sbi->ll_ra_info; + bool hit = flags & LL_RAS_HIT; + int zero = 0, stride_detect = 0, ra_miss = 0; + ENTRY; - cfs_spin_lock(&sbi->ll_lock); - cfs_spin_lock(&ras->ras_lock); + spin_lock(&ras->ras_lock); + if (!hit) + CDEBUG(D_READA, DFID " pages at %lu miss.\n", + PFID(ll_inode2fid(inode)), index); ll_ra_stats_inc_sbi(sbi, hit ? RA_STAT_HIT : RA_STAT_MISS); /* reset the read-ahead window in two cases. First when the app seeks @@ -996,224 +760,501 @@ void ras_update(struct ll_sb_info *sbi, struct inode *inode, * and only occurs once per open file. Normal RA behavior is reverted * to for subsequent IO. The mmap case does not increment * ras_requests and thus can never trigger this behavior. */ - if (ras->ras_requests == 2 && !ras->ras_request_index) { - __u64 kms_pages; + if (ras->ras_requests >= 2 && !ras->ras_request_index) { + __u64 kms_pages; - kms_pages = (i_size_read(inode) + CFS_PAGE_SIZE - 1) >> - CFS_PAGE_SHIFT; + kms_pages = (i_size_read(inode) + PAGE_SIZE - 1) >> + PAGE_SHIFT; - CDEBUG(D_READA, "kmsp "LPU64" mwp %lu mp %lu\n", kms_pages, + CDEBUG(D_READA, "kmsp %llu mwp %lu mp %lu\n", kms_pages, ra->ra_max_read_ahead_whole_pages, ra->ra_max_pages_per_file); if (kms_pages && kms_pages <= ra->ra_max_read_ahead_whole_pages) { ras->ras_window_start = 0; - ras->ras_last_readpage = 0; - ras->ras_next_readahead = 0; + ras->ras_next_readahead = index + 1; ras->ras_window_len = min(ra->ra_max_pages_per_file, ra->ra_max_read_ahead_whole_pages); GOTO(out_unlock, 0); } } - if (zero) { - /* check whether it is in stride I/O mode*/ - if (!index_in_stride_window(index, ras, inode)) { - if (ras->ras_consecutive_stride_requests == 0 && - ras->ras_request_index == 0) { - ras_update_stride_detector(ras, index); - ras->ras_consecutive_stride_requests ++; - } else { - ras_stride_reset(ras); - } - ras_reset(ras, index); - ras->ras_consecutive_pages++; - GOTO(out_unlock, 0); - } else { - ras->ras_consecutive_pages = 0; - ras->ras_consecutive_requests = 0; - if (++ras->ras_consecutive_stride_requests > 1) - stride_detect = 1; - RAS_CDEBUG(ras); - } - } else { - if (ra_miss) { - if (index_in_stride_window(index, ras, inode) && - stride_io_mode(ras)) { - /*If stride-RA hit cache miss, the stride dector - *will not be reset to avoid the overhead of - *redetecting read-ahead mode */ - if (index != ras->ras_last_readpage + 1) - ras->ras_consecutive_pages = 0; - ras_reset(ras, index); - RAS_CDEBUG(ras); - } else { - /* Reset both stride window and normal RA - * window */ - ras_reset(ras, index); - ras->ras_consecutive_pages++; - ras_stride_reset(ras); - GOTO(out_unlock, 0); - } - } else if (stride_io_mode(ras)) { - /* If this is contiguous read but in stride I/O mode - * currently, check whether stride step still is valid, - * if invalid, it will reset the stride ra window*/ - if (!index_in_stride_window(index, ras, inode)) { - /* Shrink stride read-ahead window to be zero */ - ras_stride_reset(ras); - ras->ras_window_len = 0; - ras->ras_next_readahead = index; - } - } - } - ras->ras_consecutive_pages++; - ras->ras_last_readpage = index; - ras_set_start(ras, index); - - if (stride_io_mode(ras)) - /* Since stride readahead is sentivite to the offset - * of read-ahead, so we use original offset here, - * instead of ras_window_start, which is 1M aligned*/ - ras->ras_next_readahead = max(index, - ras->ras_next_readahead); - else - ras->ras_next_readahead = max(ras->ras_window_start, - ras->ras_next_readahead); - RAS_CDEBUG(ras); - - /* Trigger RA in the mmap case where ras_consecutive_requests - * is not incremented and thus can't be used to trigger RA */ - if (!ras->ras_window_len && ras->ras_consecutive_pages == 4) { - ras->ras_window_len = RAS_INCREASE_STEP; - GOTO(out_unlock, 0); - } - - /* Initially reset the stride window offset to next_readahead*/ - if (ras->ras_consecutive_stride_requests == 2 && stride_detect) { - /** - * Once stride IO mode is detected, next_readahead should be - * reset to make sure next_readahead > stride offset - */ - ras->ras_next_readahead = max(index, ras->ras_next_readahead); - ras->ras_stride_offset = index; - ras->ras_window_len = RAS_INCREASE_STEP; - } - - /* The initial ras_window_len is set to the request size. To avoid - * uselessly reading and discarding pages for random IO the window is - * only increased once per consecutive request received. */ - if ((ras->ras_consecutive_requests > 1 || stride_detect) && - !ras->ras_request_index) - ras_increase_window(ras, ra, inode); - EXIT; + if (zero) { + /* check whether it is in stride I/O mode*/ + if (!index_in_stride_window(ras, index)) { + if (ras->ras_consecutive_stride_requests == 0 && + ras->ras_request_index == 0) { + ras_update_stride_detector(ras, index); + ras->ras_consecutive_stride_requests++; + } else { + ras_stride_reset(ras); + } + ras_reset(inode, ras, index); + ras->ras_consecutive_pages++; + GOTO(out_unlock, 0); + } else { + ras->ras_consecutive_pages = 0; + ras->ras_consecutive_requests = 0; + if (++ras->ras_consecutive_stride_requests > 1) + stride_detect = 1; + RAS_CDEBUG(ras); + } + } else { + if (ra_miss) { + if (index_in_stride_window(ras, index) && + stride_io_mode(ras)) { + if (index != ras->ras_last_readpage + 1) + ras->ras_consecutive_pages = 0; + ras_reset(inode, ras, index); + + /* If stride-RA hit cache miss, the stride + * detector will not be reset to avoid the + * overhead of redetecting read-ahead mode, + * but on the condition that the stride window + * is still intersect with normal sequential + * read-ahead window. */ + if (ras->ras_window_start < + ras->ras_stride_offset) + ras_stride_reset(ras); + RAS_CDEBUG(ras); + } else { + /* Reset both stride window and normal RA + * window */ + ras_reset(inode, ras, index); + ras->ras_consecutive_pages++; + ras_stride_reset(ras); + GOTO(out_unlock, 0); + } + } else if (stride_io_mode(ras)) { + /* If this is contiguous read but in stride I/O mode + * currently, check whether stride step still is valid, + * if invalid, it will reset the stride ra window*/ + if (!index_in_stride_window(ras, index)) { + /* Shrink stride read-ahead window to be zero */ + ras_stride_reset(ras); + ras->ras_window_len = 0; + ras->ras_next_readahead = index; + } + } + } + ras->ras_consecutive_pages++; + ras->ras_last_readpage = index; + ras_set_start(inode, ras, index); + + if (stride_io_mode(ras)) { + /* Since stride readahead is sentivite to the offset + * of read-ahead, so we use original offset here, + * instead of ras_window_start, which is RPC aligned */ + ras->ras_next_readahead = max(index, ras->ras_next_readahead); + ras->ras_window_start = max(ras->ras_stride_offset, + ras->ras_window_start); + } else { + if (ras->ras_next_readahead < ras->ras_window_start) + ras->ras_next_readahead = ras->ras_window_start; + if (!hit) + ras->ras_next_readahead = index + 1; + } + RAS_CDEBUG(ras); + + /* Trigger RA in the mmap case where ras_consecutive_requests + * is not incremented and thus can't be used to trigger RA */ + if (ras->ras_consecutive_pages >= 4 && flags & LL_RAS_MMAP) { + ras_increase_window(inode, ras, ra); + /* reset consecutive pages so that the readahead window can + * grow gradually. */ + ras->ras_consecutive_pages = 0; + GOTO(out_unlock, 0); + } + + /* Initially reset the stride window offset to next_readahead*/ + if (ras->ras_consecutive_stride_requests == 2 && stride_detect) { + /** + * Once stride IO mode is detected, next_readahead should be + * reset to make sure next_readahead > stride offset + */ + ras->ras_next_readahead = max(index, ras->ras_next_readahead); + ras->ras_stride_offset = index; + ras->ras_window_start = max(index, ras->ras_window_start); + } + + /* The initial ras_window_len is set to the request size. To avoid + * uselessly reading and discarding pages for random IO the window is + * only increased once per consecutive request received. */ + if ((ras->ras_consecutive_requests > 1 || stride_detect) && + !ras->ras_request_index) + ras_increase_window(inode, ras, ra); + EXIT; out_unlock: - RAS_CDEBUG(ras); - ras->ras_request_index++; - cfs_spin_unlock(&ras->ras_lock); - cfs_spin_unlock(&sbi->ll_lock); - return; + RAS_CDEBUG(ras); + ras->ras_request_index++; + spin_unlock(&ras->ras_lock); + return; } -int ll_writepage(struct page *vmpage, struct writeback_control *unused) +int ll_writepage(struct page *vmpage, struct writeback_control *wbc) { - struct inode *inode = vmpage->mapping->host; + struct inode *inode = vmpage->mapping->host; + struct ll_inode_info *lli = ll_i2info(inode); struct lu_env *env; struct cl_io *io; struct cl_page *page; struct cl_object *clob; - struct cl_2queue *queue; - struct cl_env_nest nest; + bool redirtied = false; + bool unlocked = false; int result; + __u16 refcheck; ENTRY; LASSERT(PageLocked(vmpage)); LASSERT(!PageWriteback(vmpage)); - if (ll_i2dtexp(inode) == NULL) - RETURN(-EINVAL); + LASSERT(ll_i2dtexp(inode) != NULL); - env = cl_env_nested_get(&nest); - if (IS_ERR(env)) - RETURN(PTR_ERR(env)); + env = cl_env_get(&refcheck); + if (IS_ERR(env)) + GOTO(out, result = PTR_ERR(env)); - io = &ccc_env_info(env)->cti_io; - queue = &vvp_env_info(env)->vti_queue; clob = ll_i2info(inode)->lli_clob; LASSERT(clob != NULL); + io = vvp_env_thread_io(env); io->ci_obj = clob; + io->ci_ignore_layout = 1; result = cl_io_init(env, io, CIT_MISC, clob); if (result == 0) { page = cl_page_find(env, clob, vmpage->index, vmpage, CPT_CACHEABLE); - if (!IS_ERR(page)) { - lu_ref_add(&page->cp_reference, "writepage", - cfs_current()); - cl_page_assume(env, io, page); - /* - * Mark page dirty, because this is what - * ->vio_submit()->cpo_prep_write() assumes. - * - * XXX better solution is to detect this from within - * cl_io_submit_rw() somehow. - */ - set_page_dirty(vmpage); - cl_2queue_init_page(queue, page); - result = cl_io_submit_rw(env, io, CRT_WRITE, - queue, CRP_NORMAL); - cl_page_list_disown(env, io, &queue->c2_qin); - if (result != 0) { - /* - * There is no need to clear PG_writeback, as - * cl_io_submit_rw() calls completion callback - * on failure. - */ - /* - * Re-dirty page on error so it retries write, - * but not in case when IO has actually - * occurred and completed with an error. - */ - if (!PageError(vmpage)) - set_page_dirty(vmpage); - } - LASSERT(!cl_page_is_owned(page, io)); - lu_ref_del(&page->cp_reference, - "writepage", cfs_current()); - cl_page_put(env, page); - cl_2queue_fini(env, queue); - } + if (!IS_ERR(page)) { + lu_ref_add(&page->cp_reference, "writepage", + current); + cl_page_assume(env, io, page); + result = cl_page_flush(env, io, page); + if (result != 0) { + /* + * Re-dirty page on error so it retries write, + * but not in case when IO has actually + * occurred and completed with an error. + */ + if (!PageError(vmpage)) { + redirty_page_for_writepage(wbc, vmpage); + result = 0; + redirtied = true; + } + } + cl_page_disown(env, io, page); + unlocked = true; + lu_ref_del(&page->cp_reference, + "writepage", current); + cl_page_put(env, page); + } else { + result = PTR_ERR(page); + } } cl_io_fini(env, io); - cl_env_nested_put(&nest, env); - RETURN(result); + + if (redirtied && wbc->sync_mode == WB_SYNC_ALL) { + loff_t offset = cl_offset(clob, vmpage->index); + + /* Flush page failed because the extent is being written out. + * Wait for the write of extent to be finished to avoid + * breaking kernel which assumes ->writepage should mark + * PageWriteback or clean the page. */ + result = cl_sync_file_range(inode, offset, + offset + PAGE_SIZE - 1, + CL_FSYNC_LOCAL, 1); + if (result > 0) { + /* actually we may have written more than one page. + * decreasing this page because the caller will count + * it. */ + wbc->nr_to_write -= result - 1; + result = 0; + } + } + + cl_env_put(env, &refcheck); + GOTO(out, result); + +out: + if (result < 0) { + if (!lli->lli_async_rc) + lli->lli_async_rc = result; + SetPageError(vmpage); + if (!unlocked) + unlock_page(vmpage); + } + return result; } -int ll_readpage(struct file *file, struct page *vmpage) +int ll_writepages(struct address_space *mapping, struct writeback_control *wbc) { - struct ll_cl_context *lcc; - int result; - ENTRY; + struct inode *inode = mapping->host; + loff_t start; + loff_t end; + enum cl_fsync_mode mode; + int range_whole = 0; + int result; + ENTRY; + + if (wbc->range_cyclic) { + start = mapping->writeback_index << PAGE_SHIFT; + end = OBD_OBJECT_EOF; + } else { + start = wbc->range_start; + end = wbc->range_end; + if (end == LLONG_MAX) { + end = OBD_OBJECT_EOF; + range_whole = start == 0; + } + } + + mode = CL_FSYNC_NONE; + if (wbc->sync_mode == WB_SYNC_ALL) + mode = CL_FSYNC_LOCAL; + + if (ll_i2info(inode)->lli_clob == NULL) + RETURN(0); + + /* for directio, it would call writepages() to evict cached pages + * inside the IO context of write, which will cause deadlock at + * layout_conf since it waits for active IOs to complete. */ + result = cl_sync_file_range(inode, start, end, mode, 1); + if (result > 0) { + wbc->nr_to_write -= result; + result = 0; + } + + if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) { + if (end == OBD_OBJECT_EOF) + mapping->writeback_index = 0; + else + mapping->writeback_index = (end >> PAGE_SHIFT) + 1; + } + RETURN(result); +} - lcc = ll_cl_init(file, vmpage, 0); - if (!IS_ERR(lcc)) { - struct lu_env *env = lcc->lcc_env; - struct cl_io *io = lcc->lcc_io; - struct cl_page *page = lcc->lcc_page; - - LASSERT(page->cp_type == CPT_CACHEABLE); - if (likely(!PageUptodate(vmpage))) { - cl_page_assume(env, io, page); - result = cl_io_read_page(env, io, page); - } else { - /* Page from a non-object file. */ - LASSERT(!ll_i2info(vmpage->mapping->host)->lli_smd); - unlock_page(vmpage); - result = 0; - } - ll_cl_fini(lcc); - } else { - result = PTR_ERR(lcc); +struct ll_cl_context *ll_cl_find(struct file *file) +{ + struct ll_file_data *fd = LUSTRE_FPRIVATE(file); + struct ll_cl_context *lcc; + struct ll_cl_context *found = NULL; + + read_lock(&fd->fd_lock); + list_for_each_entry(lcc, &fd->fd_lccs, lcc_list) { + if (lcc->lcc_cookie == current) { + found = lcc; + break; + } + } + read_unlock(&fd->fd_lock); + + return found; +} + +void ll_cl_add(struct file *file, const struct lu_env *env, struct cl_io *io, + enum lcc_type type) +{ + struct ll_file_data *fd = LUSTRE_FPRIVATE(file); + struct ll_cl_context *lcc = &ll_env_info(env)->lti_io_ctx; + + memset(lcc, 0, sizeof(*lcc)); + INIT_LIST_HEAD(&lcc->lcc_list); + lcc->lcc_cookie = current; + lcc->lcc_env = env; + lcc->lcc_io = io; + lcc->lcc_type = type; + + write_lock(&fd->fd_lock); + list_add(&lcc->lcc_list, &fd->fd_lccs); + write_unlock(&fd->fd_lock); +} + +void ll_cl_remove(struct file *file, const struct lu_env *env) +{ + struct ll_file_data *fd = LUSTRE_FPRIVATE(file); + struct ll_cl_context *lcc = &ll_env_info(env)->lti_io_ctx; + + write_lock(&fd->fd_lock); + list_del_init(&lcc->lcc_list); + write_unlock(&fd->fd_lock); +} + +static int ll_io_read_page(const struct lu_env *env, struct cl_io *io, + struct cl_page *page, struct file *file) +{ + struct inode *inode = vvp_object_inode(page->cp_obj); + struct ll_sb_info *sbi = ll_i2sbi(inode); + struct ll_file_data *fd = LUSTRE_FPRIVATE(file); + struct ll_readahead_state *ras = &fd->fd_ras; + struct cl_2queue *queue = &io->ci_queue; + struct vvp_page *vpg; + int rc = 0; + bool uptodate; + ENTRY; + + vpg = cl2vvp_page(cl_object_page_slice(page->cp_obj, page)); + uptodate = vpg->vpg_defer_uptodate; + + if (sbi->ll_ra_info.ra_max_pages_per_file > 0 && + sbi->ll_ra_info.ra_max_pages > 0 && + !vpg->vpg_ra_updated) { + struct vvp_io *vio = vvp_env_io(env); + enum ras_update_flags flags = 0; + + if (uptodate) + flags |= LL_RAS_HIT; + if (!vio->vui_ra_valid) + flags |= LL_RAS_MMAP; + ras_update(sbi, inode, ras, vvp_index(vpg), flags); + } + + cl_2queue_init(queue); + if (uptodate) { + vpg->vpg_ra_used = 1; + cl_page_export(env, page, 1); + cl_page_disown(env, io, page); + } else { + cl_2queue_add(queue, page); + } + + if (sbi->ll_ra_info.ra_max_pages_per_file > 0 && + sbi->ll_ra_info.ra_max_pages > 0) { + int rc2; + + rc2 = ll_readahead(env, io, &queue->c2_qin, ras, + uptodate); + CDEBUG(D_READA, DFID "%d pages read ahead at %lu\n", + PFID(ll_inode2fid(inode)), rc2, vvp_index(vpg)); + } + + if (queue->c2_qin.pl_nr > 0) + rc = cl_io_submit_rw(env, io, CRT_READ, queue); + + /* + * Unlock unsent pages in case of error. + */ + cl_page_list_disown(env, io, &queue->c2_qin); + cl_2queue_fini(env, queue); + + RETURN(rc); +} + +int ll_readpage(struct file *file, struct page *vmpage) +{ + struct inode *inode = file_inode(file); + struct cl_object *clob = ll_i2info(inode)->lli_clob; + struct ll_cl_context *lcc; + const struct lu_env *env = NULL; + struct cl_io *io = NULL; + struct cl_page *page; + int result; + ENTRY; + + lcc = ll_cl_find(file); + if (lcc != NULL) { + env = lcc->lcc_env; + io = lcc->lcc_io; + } + + if (io == NULL) { /* fast read */ + struct inode *inode = file_inode(file); + struct ll_file_data *fd = LUSTRE_FPRIVATE(file); + struct ll_readahead_state *ras = &fd->fd_ras; + struct lu_env *local_env = NULL; + struct vvp_page *vpg; + + result = -ENODATA; + + /* TODO: need to verify the layout version to make sure + * the page is not invalid due to layout change. */ + page = cl_vmpage_page(vmpage, clob); + if (page == NULL) { + unlock_page(vmpage); + RETURN(result); + } + + if (!env) { + local_env = cl_env_percpu_get(); + env = local_env; + } + + vpg = cl2vvp_page(cl_object_page_slice(page->cp_obj, page)); + if (vpg->vpg_defer_uptodate) { + enum ras_update_flags flags = LL_RAS_HIT; + + if (lcc && lcc->lcc_type == LCC_MMAP) + flags |= LL_RAS_MMAP; + + /* For fast read, it updates read ahead state only + * if the page is hit in cache because non cache page + * case will be handled by slow read later. */ + ras_update(ll_i2sbi(inode), inode, ras, vvp_index(vpg), + flags); + /* avoid duplicate ras_update() call */ + vpg->vpg_ra_updated = 1; + + /* Check if we can issue a readahead RPC, if that is + * the case, we can't do fast IO because we will need + * a cl_io to issue the RPC. */ + if (ras->ras_window_start + ras->ras_window_len < + ras->ras_next_readahead + PTLRPC_MAX_BRW_PAGES) { + /* export the page and skip io stack */ + vpg->vpg_ra_used = 1; + cl_page_export(env, page, 1); + result = 0; + } + } + + /* release page refcount before unlocking the page to ensure + * the object won't be destroyed in the calling path of + * cl_page_put(). Please see comment in ll_releasepage(). */ + cl_page_put(env, page); + unlock_page(vmpage); + if (local_env) + cl_env_percpu_put(local_env); + + RETURN(result); + } + + LASSERT(io->ci_state == CIS_IO_GOING); + page = cl_page_find(env, clob, vmpage->index, vmpage, CPT_CACHEABLE); + if (!IS_ERR(page)) { + LASSERT(page->cp_type == CPT_CACHEABLE); + if (likely(!PageUptodate(vmpage))) { + cl_page_assume(env, io, page); + result = ll_io_read_page(env, io, page, file); + } else { + /* Page from a non-object file. */ + unlock_page(vmpage); + result = 0; + } + cl_page_put(env, page); + } else { + unlock_page(vmpage); + result = PTR_ERR(page); } - RETURN(result); + RETURN(result); } +int ll_page_sync_io(const struct lu_env *env, struct cl_io *io, + struct cl_page *page, enum cl_req_type crt) +{ + struct cl_2queue *queue; + int result; + + LASSERT(io->ci_type == CIT_READ || io->ci_type == CIT_WRITE); + + queue = &io->ci_queue; + cl_2queue_init_page(queue, page); + + result = cl_io_submit_sync(env, io, crt, queue, 0); + LASSERT(cl_page_is_owned(page, io)); + + if (crt == CRT_READ) + /* + * in CRT_WRITE case page is left locked even in case of + * error. + */ + cl_page_list_disown(env, io, &queue->c2_qin); + cl_2queue_fini(env, queue); + + return result; +}