-/* -*- 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.
/*
* Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
-#include <linux/smp_lock.h>
#include <linux/unistd.h>
-#include <linux/version.h>
-#include <asm/system.h>
+#include <linux/writeback.h>
#include <asm/uaccess.h>
#include <linux/fs.h>
#include <asm/uaccess.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
-#include <linux/smp_lock.h>
/* current_is_kswapd() */
#include <linux/swap.h>
#include "llite_internal.h"
#include <linux/lustre_compat25.h>
-/* 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)
-{
- ENTRY;
-
- CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p) to %llu\n", inode->i_ino,
- inode->i_generation, inode, i_size_read(inode));
-
- ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_TRUNC, 1);
-
- EXIT;
- return;
-} /* ll_truncate */
-
/**
* Finalizes cl-data before exiting typical address_space operation. Dual to
* ll_cl_init().
cio = ccc_env_io(env);
io = cio->cui_cl.cis_io;
if (io == NULL && create) {
- loff_t pos;
+ struct inode *inode = vmpage->mapping->host;
+ loff_t pos;
+
+ if (mutex_trylock(&inode->i_mutex)) {
+ mutex_unlock(&(inode)->i_mutex);
+
+ /* this is too bad. Someone is trying to write the
+ * page w/o holding inode mutex. This means we can
+ * add dirty pages into cache during truncate */
+ CERROR("Proc %s is dirting page w/o inode lock, this"
+ "will break truncate.\n", cfs_current()->comm);
+ libcfs_debug_dumpstack(NULL);
+ LBUG();
+ return ERR_PTR(-EIO);
+ }
/*
* Loop-back driver calls ->prepare_write() and ->sendfile()
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);
+
+ result = cl_io_prepare_write(env, io, page, from, to);
if (result == 0) {
/*
* Add a reference, so that page is not evicted from
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, struct ra_io_arg *ria,
- 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)
{
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.
- */
- if (ra->ra_max_pages < atomic_read(&ra->ra_cur_pages))
+ * performance a lot. */
+ ret = min(ra->ra_max_pages - cfs_atomic_read(&ra->ra_cur_pages), pages);
+ if (ret < 0 || ret < min_t(long, PTLRPC_MAX_BRW_PAGES, pages))
GOTO(out, ret = 0);
- 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))
- GOTO(out, ret = 0);
-
- if (ria->ria_pages == 0)
- /* it needs 1M align again after trimed by ra_max_pages*/
- if (ret >= ((ria->ria_start + ret) % PTLRPC_MAX_BRW_PAGES))
- ret -= (ria->ria_start + ret) % PTLRPC_MAX_BRW_PAGES;
+ /* If the non-strided (ria_pages == 0) readahead window
+ * (ria_start + ret) has grown across an RPC boundary, then trim
+ * readahead size by the amount beyond the RPC so it ends on an
+ * RPC boundary. If the readahead window is already ending on
+ * an RPC boundary (beyond_rpc == 0), or smaller than a full
+ * RPC (beyond_rpc < ret) the readahead size is unchanged.
+ * The (beyond_rpc != 0) check is skipped since the conditional
+ * branch is more expensive than subtracting zero from the result.
+ *
+ * Strided read is left unaligned to avoid small fragments beyond
+ * the RPC boundary from needing an extra read RPC. */
+ if (ria->ria_pages == 0) {
+ long beyond_rpc = (ria->ria_start + ret) % PTLRPC_MAX_BRW_PAGES;
+ if (/* beyond_rpc != 0 && */ beyond_rpc < ret)
+ ret -= beyond_rpc;
+ }
if (cfs_atomic_add_return(ret, &ra->ra_cur_pages) > ra->ra_max_pages) {
cfs_atomic_sub(ret, &ra->ra_cur_pages);
void ll_ra_read_in(struct file *f, struct ll_ra_read *rar)
{
- struct ll_readahead_state *ras;
+ struct ll_readahead_state *ras;
- ras = ll_ras_get(f);
+ 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;
+ 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);
+ cfs_list_add(&rar->lrr_linkage, &ras->ras_read_beads);
+ spin_unlock(&ras->ras_lock);
}
void ll_ra_read_ex(struct file *f, struct ll_ra_read *rar)
{
- struct ll_readahead_state *ras;
+ struct ll_readahead_state *ras;
- ras = ll_ras_get(f);
+ ras = ll_ras_get(f);
- cfs_spin_lock(&ras->ras_lock);
- cfs_list_del_init(&rar->lrr_linkage);
- cfs_spin_unlock(&ras->ras_lock);
+ spin_lock(&ras->ras_lock);
+ cfs_list_del_init(&rar->lrr_linkage);
+ spin_unlock(&ras->ras_lock);
}
static struct ll_ra_read *ll_ra_read_get_locked(struct ll_readahead_state *ras)
struct ll_ra_read *ll_ra_read_get(struct file *f)
{
- struct ll_readahead_state *ras;
- struct ll_ra_read *bead;
+ struct ll_readahead_state *ras;
+ struct ll_ra_read *bead;
- ras = ll_ras_get(f);
+ 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;
+ spin_lock(&ras->ras_lock);
+ bead = ll_ra_read_get_locked(ras);
+ spin_unlock(&ras->ras_lock);
+ return bead;
}
static int cl_read_ahead_page(const struct lu_env *env, struct cl_io *io,
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);
+ lu_ref_add(&page->cp_reference, "ra", cfs_current());
+ cp = cl2ccc_page(cl_page_at(page, &vvp_device_type));
+ if (!cp->cpg_defer_uptodate && !PageUptodate(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_delete(env, page);
rc = -ENOLCK;
}
- } else
- /* skip completed pages */
- cl_page_unassume(env, io, page);
+ } 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);
#ifdef __GFP_NOWARN
gfp_mask |= __GFP_NOWARN;
#endif
- vmpage = grab_cache_page_nowait_gfp(mapping, index, gfp_mask);
+ vmpage = grab_cache_page_nowait(mapping, index);
if (vmpage != NULL) {
/* Check if vmpage was truncated or reclaimed */
if (vmpage->mapping == mapping) {
ria->ria_start, ria->ria_end, ria->ria_stoff, ria->ria_length,\
ria->ria_pages)
-#define RAS_INCREASE_STEP PTLRPC_MAX_BRW_PAGES
+/* Limit this to the blocksize instead of PTLRPC_BRW_MAX_SIZE, since we don't
+ * know what the actual RPC size is. If this needs to change, it makes more
+ * sense to tune the i_blkbits value for the file based on the OSTs it is
+ * striped over, rather than having a constant value for all files here. */
+
+/* RAS_INCREASE_STEP should be (1UL << (inode->i_blkbits - CFS_PAGE_SHIFT)).
+ * Temprarily set RAS_INCREASE_STEP to 1MB. After 4MB RPC is enabled
+ * by default, this should be adjusted corresponding with max_read_ahead_mb
+ * and max_read_ahead_per_file_mb otherwise the readahead budget can be used
+ * up quickly which will affect read performance siginificantly. See LU-2816 */
+#define RAS_INCREASE_STEP(inode) (ONE_MB_BRW_SIZE >> CFS_PAGE_SHIFT)
static inline int stride_io_mode(struct ll_readahead_state *ras)
{
RETURN(0);
}
- cfs_spin_lock(&ras->ras_lock);
+ spin_lock(&ras->ras_lock);
if (vio->cui_ra_window_set)
bead = &vio->cui_bead;
else
end = ras->ras_window_start + ras->ras_window_len - 1;
}
if (end != 0) {
- unsigned long tmp_end;
+ unsigned long rpc_boundary;
/*
* Align RA window to an optimal boundary.
*
* be aligned to the RAID stripe size in the future and that
* is more important than the RPC size.
*/
- tmp_end = ((end + 1) & (~(PTLRPC_MAX_BRW_PAGES - 1))) - 1;
- if (tmp_end > start)
- end = tmp_end;
+ /* Note: we only trim the RPC, instead of extending the RPC
+ * to the boundary, so to avoid reading too much pages during
+ * random reading. */
+ rpc_boundary = ((end + 1) & (~(PTLRPC_MAX_BRW_PAGES - 1)));
+ if (rpc_boundary > 0)
+ rpc_boundary--;
+
+ if (rpc_boundary > start)
+ end = rpc_boundary;
/* Truncate RA window to end of file */
end = min(end, (unsigned long)((kms - 1) >> CFS_PAGE_SHIFT));
ria->ria_length = ras->ras_stride_length;
ria->ria_pages = ras->ras_stride_pages;
}
- cfs_spin_unlock(&ras->ras_lock);
+ spin_unlock(&ras->ras_lock);
if (end == 0) {
ll_ra_stats_inc(mapping, RA_STAT_ZERO_WINDOW);
if (reserved < len)
ll_ra_stats_inc(mapping, RA_STAT_MAX_IN_FLIGHT);
- CDEBUG(D_READA, "reserved page %lu \n", reserved);
+ CDEBUG(D_READA, "reserved page %lu ra_cur %d ra_max %lu\n", reserved,
+ cfs_atomic_read(&ll_i2sbi(inode)->ll_ra_info.ra_cur_pages),
+ ll_i2sbi(inode)->ll_ra_info.ra_max_pages);
ret = ll_read_ahead_pages(env, io, queue,
ria, &reserved, mapping, &ra_end);
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);
+ if (ra_end != end + 1) {
+ 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);
+ }
+ 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 = index & (~(RAS_INCREASE_STEP(inode) - 1));
}
/* 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);
+
+ RAS_CDEBUG(ras);
}
/* called with the ras_lock held or from places where it doesn't matter */
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_reset(inode, ras, 0);
+ ras->ras_requests = 0;
+ CFS_INIT_LIST_HEAD(&ras->ras_read_beads);
}
/*
* 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,
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_INCREASE_STEP(inode));
+ else
+ ras->ras_window_len = min(ras->ras_window_len +
+ RAS_INCREASE_STEP(inode),
+ ra->ra_max_pages_per_file);
}
void ras_update(struct ll_sb_info *sbi, struct inode *inode,
- struct ll_readahead_state *ras, unsigned long index,
- unsigned hit)
+ struct ll_readahead_state *ras, unsigned long index,
+ unsigned hit)
{
- 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;
+ int zero = 0, stride_detect = 0, ra_miss = 0;
+ ENTRY;
- cfs_spin_lock(&ras->ras_lock);
+ spin_lock(&ras->ras_lock);
ll_ra_stats_inc_sbi(sbi, hit ? RA_STAT_HIT : RA_STAT_MISS);
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 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(inode, ras, index);
+ 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);
+ 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(inode);
+ 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(inode);
+ }
+
+ /* 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);
- return;
+ RAS_CDEBUG(ras);
+ ras->ras_request_index++;
+ spin_unlock(&ras->ras_lock);
+ return;
}
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;
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_nested_get(&nest);
+ if (IS_ERR(env))
+ GOTO(out, result = PTR_ERR(env));
- queue = &vvp_env_info(env)->vti_queue;
clob = ll_i2info(inode)->lli_clob;
LASSERT(clob != NULL);
io = ccc_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,
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);
- 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;
- }
- }
- cl_page_list_disown(env, io, &queue->c2_qin);
- LASSERT(!cl_page_is_owned(page, io));
+ 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", cfs_current());
cl_page_put(env, page);
- cl_2queue_fini(env, queue);
- }
+ } else {
+ result = PTR_ERR(page);
+ }
}
cl_io_fini(env, io);
+
+ 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 + CFS_PAGE_SIZE - 1,
+ CL_FSYNC_LOCAL);
+ 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_nested_put(&nest, env);
- RETURN(result);
+ 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_writepages(struct address_space *mapping, struct writeback_control *wbc)
+{
+ 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 << CFS_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;
+
+ result = cl_sync_file_range(inode, start, end, mode);
+ 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)
+ end = i_size_read(inode);
+ mapping->writeback_index = (end >> CFS_PAGE_SHIFT) + 1;
+ }
+ RETURN(result);
}
int ll_readpage(struct file *file, struct page *vmpage)
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;
}
git://git.whamcloud.com / fs / lustre-release.git / blobdiff