[PATCH 05/41] staging: lustre: clio: Revise read ahead implementation

From: James Simmons
Date: Sun Oct 02 2016 - 22:29:08 EST

From: Jinshan Xiong <jinshan.xiong@xxxxxxxxx>

In this implementation, read ahead will hold the underlying DLM lock
to add read ahead pages. A new cl_io operation cio_read_ahead() is
added for this purpose. It takes parameter cl_read_ahead{} so that
each layer can adjust it by their own requirements. For example, at
OSC layer, it will make sure the read ahead region is covered by a
LDLM lock; at the LOV layer, it will make sure that the region won't
cross stripe boundary.

Legacy callback cpo_is_under_lock() is removed.

Signed-off-by: Jinshan Xiong <jinshan.xiong@xxxxxxxxx>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3259
Reviewed-on: http://review.whamcloud.com/10859
Reviewed-by: John L. Hammond <john.hammond@xxxxxxxxx>
Reviewed-by: Bobi Jam <bobijam@xxxxxxxxxxx>
Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx>
Signed-off-by: James Simmons <jsimmons@xxxxxxxxxxxxx>
---
drivers/staging/lustre/lustre/include/cl_object.h | 63 +++---
.../staging/lustre/lustre/llite/llite_internal.h | 7 +-
drivers/staging/lustre/lustre/llite/rw.c | 218 ++++++++++++--------
drivers/staging/lustre/lustre/llite/vvp_io.c | 47 ++---
drivers/staging/lustre/lustre/llite/vvp_page.c | 16 --
drivers/staging/lustre/lustre/lov/lov_io.c | 58 +++++
drivers/staging/lustre/lustre/lov/lov_page.c | 46 ----
drivers/staging/lustre/lustre/obdclass/cl_io.c | 57 +----
drivers/staging/lustre/lustre/obdclass/cl_page.c | 47 -----
drivers/staging/lustre/lustre/osc/osc_cache.c | 3 +-
drivers/staging/lustre/lustre/osc/osc_internal.h | 17 ++-
drivers/staging/lustre/lustre/osc/osc_io.c | 41 ++++-
drivers/staging/lustre/lustre/osc/osc_lock.c | 12 +-
drivers/staging/lustre/lustre/osc/osc_page.c | 20 --
14 files changed, 312 insertions(+), 340 deletions(-)

diff --git a/drivers/staging/lustre/lustre/include/cl_object.h b/drivers/staging/lustre/lustre/include/cl_object.h
index 89292c9..bf93c1e 100644
--- a/drivers/staging/lustre/lustre/include/cl_object.h
+++ b/drivers/staging/lustre/lustre/include/cl_object.h
@@ -884,26 +884,6 @@ struct cl_page_operations {
/** Destructor. Frees resources and slice itself. */
void (*cpo_fini)(const struct lu_env *env,
struct cl_page_slice *slice);
-
- /**
- * Checks whether the page is protected by a cl_lock. This is a
- * per-layer method, because certain layers have ways to check for the
- * lock much more efficiently than through the generic locks scan, or
- * implement locking mechanisms separate from cl_lock, e.g.,
- * LL_FILE_GROUP_LOCKED in vvp. If \a pending is true, check for locks
- * being canceled, or scheduled for cancellation as soon as the last
- * user goes away, too.
- *
- * \retval -EBUSY: page is protected by a lock of a given mode;
- * \retval -ENODATA: page is not protected by a lock;
- * \retval 0: this layer cannot decide.
- *
- * \see cl_page_is_under_lock()
- */
- int (*cpo_is_under_lock)(const struct lu_env *env,
- const struct cl_page_slice *slice,
- struct cl_io *io, pgoff_t *max);
-
/**
* Optional debugging helper. Prints given page slice.
*
@@ -1365,7 +1345,6 @@ struct cl_2queue {
* (3) sort all locks to avoid dead-locks, and acquire them
*
* (4) process the chunk: call per-page methods
- * (cl_io_operations::cio_read_page() for read,
* cl_io_operations::cio_prepare_write(),
* cl_io_operations::cio_commit_write() for write)
*
@@ -1467,6 +1446,31 @@ struct cl_io_slice {

typedef void (*cl_commit_cbt)(const struct lu_env *, struct cl_io *,
struct cl_page *);
+
+struct cl_read_ahead {
+ /*
+ * Maximum page index the readahead window will end.
+ * This is determined DLM lock coverage, RPC and stripe boundary.
+ * cra_end is included.
+ */
+ pgoff_t cra_end;
+ /*
+ * Release routine. If readahead holds resources underneath, this
+ * function should be called to release it.
+ */
+ void (*cra_release)(const struct lu_env *env, void *cbdata);
+ /* Callback data for cra_release routine */
+ void *cra_cbdata;
+};
+
+static inline void cl_read_ahead_release(const struct lu_env *env,
+ struct cl_read_ahead *ra)
+{
+ if (ra->cra_release)
+ ra->cra_release(env, ra->cra_cbdata);
+ memset(ra, 0, sizeof(*ra));
+}
+
/**
* Per-layer io operations.
* \see vvp_io_ops, lov_io_ops, lovsub_io_ops, osc_io_ops
@@ -1573,16 +1577,13 @@ struct cl_io_operations {
struct cl_page_list *queue, int from, int to,
cl_commit_cbt cb);
/**
- * Read missing page.
- *
- * Called by a top-level cl_io_operations::op[CIT_READ]::cio_start()
- * method, when it hits not-up-to-date page in the range. Optional.
+ * Decide maximum read ahead extent
*
* \pre io->ci_type == CIT_READ
*/
- int (*cio_read_page)(const struct lu_env *env,
- const struct cl_io_slice *slice,
- const struct cl_page_slice *page);
+ int (*cio_read_ahead)(const struct lu_env *env,
+ const struct cl_io_slice *slice,
+ pgoff_t start, struct cl_read_ahead *ra);
/**
* Optional debugging helper. Print given io slice.
*/
@@ -2302,8 +2303,6 @@ void cl_page_discard(const struct lu_env *env, struct cl_io *io,
void cl_page_delete(const struct lu_env *env, struct cl_page *pg);
int cl_page_is_vmlocked(const struct lu_env *env, const struct cl_page *pg);
void cl_page_export(const struct lu_env *env, struct cl_page *pg, int uptodate);
-int cl_page_is_under_lock(const struct lu_env *env, struct cl_io *io,
- struct cl_page *page, pgoff_t *max_index);
loff_t cl_offset(const struct cl_object *obj, pgoff_t idx);
pgoff_t cl_index(const struct cl_object *obj, loff_t offset);
size_t cl_page_size(const struct cl_object *obj);
@@ -2414,8 +2413,6 @@ int cl_io_lock_add(const struct lu_env *env, struct cl_io *io,
struct cl_io_lock_link *link);
int cl_io_lock_alloc_add(const struct lu_env *env, struct cl_io *io,
struct cl_lock_descr *descr);
-int cl_io_read_page(const struct lu_env *env, struct cl_io *io,
- struct cl_page *page);
int cl_io_submit_rw(const struct lu_env *env, struct cl_io *io,
enum cl_req_type iot, struct cl_2queue *queue);
int cl_io_submit_sync(const struct lu_env *env, struct cl_io *io,
@@ -2424,6 +2421,8 @@ int cl_io_submit_sync(const struct lu_env *env, struct cl_io *io,
int cl_io_commit_async(const struct lu_env *env, struct cl_io *io,
struct cl_page_list *queue, int from, int to,
cl_commit_cbt cb);
+int cl_io_read_ahead(const struct lu_env *env, struct cl_io *io,
+ pgoff_t start, struct cl_read_ahead *ra);
int cl_io_is_going(const struct lu_env *env);

/**
diff --git a/drivers/staging/lustre/lustre/llite/llite_internal.h b/drivers/staging/lustre/lustre/llite/llite_internal.h
index cd89926..b06cd3c 100644
--- a/drivers/staging/lustre/lustre/llite/llite_internal.h
+++ b/drivers/staging/lustre/lustre/llite/llite_internal.h
@@ -722,9 +722,7 @@ int ll_writepage(struct page *page, struct writeback_control *wbc);
int ll_writepages(struct address_space *, struct writeback_control *wbc);
int ll_readpage(struct file *file, struct page *page);
void ll_readahead_init(struct inode *inode, struct ll_readahead_state *ras);
-int ll_readahead(const struct lu_env *env, struct cl_io *io,
- struct cl_page_list *queue, struct ll_readahead_state *ras,
- bool hit);
+int vvp_io_write_commit(const struct lu_env *env, struct cl_io *io);
struct ll_cl_context *ll_cl_find(struct file *file);
void ll_cl_add(struct file *file, const struct lu_env *env, struct cl_io *io);
void ll_cl_remove(struct file *file, const struct lu_env *env);
@@ -1020,9 +1018,6 @@ int cl_sb_init(struct super_block *sb);
int cl_sb_fini(struct super_block *sb);
void ll_io_init(struct cl_io *io, const struct file *file, int write);

-void ras_update(struct ll_sb_info *sbi, struct inode *inode,
- struct ll_readahead_state *ras, unsigned long index,
- unsigned hit);
void ll_ra_count_put(struct ll_sb_info *sbi, unsigned long len);
void ll_ra_stats_inc(struct inode *inode, enum ra_stat which);

diff --git a/drivers/staging/lustre/lustre/llite/rw.c b/drivers/staging/lustre/lustre/llite/rw.c
index 50c0152..80cb8e0 100644
--- a/drivers/staging/lustre/lustre/llite/rw.c
+++ b/drivers/staging/lustre/lustre/llite/rw.c
@@ -180,90 +180,73 @@ void ll_ras_enter(struct file *f)
spin_unlock(&ras->ras_lock);
}

-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 cl_object *clob, pgoff_t *max_index)
+/**
+ * Initiates read-ahead of a page with given index.
+ *
+ * \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, pgoff_t index)
{
- struct page *vmpage = page->cp_vmpage;
+ enum ra_stat which = _NR_RA_STAT; /* keep gcc happy */
+ struct cl_object *clob = io->ci_obj;
+ struct inode *inode = vvp_object_inode(clob);
+ const char *msg = NULL;
+ struct cl_page *page;
struct vvp_page *vpg;
- int rc;
+ struct page *vmpage;
+ int rc = 0;
+
+ vmpage = grab_cache_page_nowait(inode->i_mapping, index);
+ if (!vmpage) {
+ which = RA_STAT_FAILED_GRAB_PAGE;
+ msg = "g_c_p_n failed";
+ rc = -EBUSY;
+ goto out;
+ }
+
+ /* 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";
+ rc = -EBUSY;
+ goto out;
+ }
+
+ 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";
+ rc = PTR_ERR(page);
+ goto out;
+ }

- rc = 0;
- cl_page_assume(env, io, 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)) {
- CDEBUG(D_READA, "page index %lu, max_index: %lu\n",
- vvp_index(vpg), *max_index);
- if (*max_index == 0 || vvp_index(vpg) > *max_index)
- rc = cl_page_is_under_lock(env, io, page, max_index);
- if (rc == 0) {
- vpg->vpg_defer_uptodate = 1;
- vpg->vpg_ra_used = 0;
- cl_page_list_add(queue, page);
- rc = 1;
- } else {
- cl_page_discard(env, io, page);
- rc = -ENOLCK;
- }
+ 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);
- return rc;
-}
-
-/**
- * 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.
- */
-static int ll_read_ahead_page(const struct lu_env *env, struct cl_io *io,
- struct cl_page_list *queue,
- pgoff_t index, pgoff_t *max_index)
-{
- struct cl_object *clob = io->ci_obj;
- struct inode *inode = vvp_object_inode(clob);
- struct page *vmpage;
- struct cl_page *page;
- enum ra_stat which = _NR_RA_STAT; /* keep gcc happy */
- int rc = 0;
- const char *msg = NULL;
-
- vmpage = grab_cache_page_nowait(inode->i_mapping, index);
+out:
if (vmpage) {
- /* Check if vmpage was truncated or reclaimed */
- if (vmpage->mapping == inode->i_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, clob, max_index);
- 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)
+ if (rc)
unlock_page(vmpage);
put_page(vmpage);
- } else {
- which = RA_STAT_FAILED_GRAB_PAGE;
- msg = "g_c_p_n failed";
}
if (msg) {
ll_ra_stats_inc(inode, which);
@@ -378,12 +361,12 @@ 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,
- unsigned long *ra_end)
+ pgoff_t *ra_end)
{
+ struct cl_read_ahead ra = { 0 };
int rc, count = 0;
bool stride_ria;
pgoff_t page_idx;
- pgoff_t max_index = 0;

LASSERT(ria);
RIA_DEBUG(ria);
@@ -392,14 +375,23 @@ static int ll_read_ahead_pages(const struct lu_env *env,
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 (!ra.cra_end || ra.cra_end < page_idx) {
+ cl_read_ahead_release(env, &ra);
+
+ rc = cl_io_read_ahead(env, io, page_idx, &ra);
+ if (rc < 0)
+ break;
+
+ LASSERTF(ra.cra_end >= page_idx,
+ "object: %p, indcies %lu / %lu\n",
+ io->ci_obj, ra.cra_end, page_idx);
+ }
+
/* If the page is inside the read-ahead window*/
- rc = ll_read_ahead_page(env, io, queue,
- page_idx, &max_index);
- if (rc == 1) {
+ rc = ll_read_ahead_page(env, io, queue, page_idx);
+ if (!rc) {
(*reserved_pages)--;
count++;
- } else if (rc == -ENOLCK) {
- break;
}
} else if (stride_ria) {
/* If it is not in the read-ahead window, and it is
@@ -425,19 +417,21 @@ static int ll_read_ahead_pages(const struct lu_env *env,
}
}
}
+ cl_read_ahead_release(env, &ra);
+
*ra_end = page_idx;
return count;
}

-int ll_readahead(const struct lu_env *env, struct cl_io *io,
- struct cl_page_list *queue, struct ll_readahead_state *ras,
- bool hit)
+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 start = 0, end = 0, reserved;
- unsigned long ra_end, len, mlen = 0;
+ unsigned long len, mlen = 0, reserved;
+ pgoff_t ra_end, start = 0, end = 0;
struct inode *inode;
struct ra_io_arg *ria = &lti->lti_ria;
struct cl_object *clob;
@@ -575,8 +569,8 @@ int ll_readahead(const struct lu_env *env, struct cl_io *io,
* 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);
+ CDEBUG(D_READA, "ra_end = %lu end = %lu stride end = %lu pages = %d\n",
+ ra_end, end, ria->ria_end, ret);

if (ra_end != end + 1) {
ll_ra_stats_inc(inode, RA_STAT_FAILED_REACH_END);
@@ -737,9 +731,9 @@ static void ras_increase_window(struct inode *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)
+static void ras_update(struct ll_sb_info *sbi, struct inode *inode,
+ struct ll_readahead_state *ras, unsigned long index,
+ unsigned int hit)
{
struct ll_ra_info *ra = &sbi->ll_ra_info;
int zero = 0, stride_detect = 0, ra_miss = 0;
@@ -1087,6 +1081,56 @@ void ll_cl_remove(struct file *file, const struct lu_env *env)
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 inode *inode = vvp_object_inode(page->cp_obj);
+ struct ll_file_data *fd = vvp_env_io(env)->vui_fd;
+ struct ll_readahead_state *ras = &fd->fd_ras;
+ struct cl_2queue *queue = &io->ci_queue;
+ struct ll_sb_info *sbi = ll_i2sbi(inode);
+ struct vvp_page *vpg;
+ int rc = 0;
+
+ vpg = cl2vvp_page(cl_object_page_slice(page->cp_obj, page));
+ if (sbi->ll_ra_info.ra_max_pages_per_file > 0 &&
+ sbi->ll_ra_info.ra_max_pages > 0)
+ ras_update(sbi, inode, ras, vvp_index(vpg),
+ vpg->vpg_defer_uptodate);
+
+ if (vpg->vpg_defer_uptodate) {
+ vpg->vpg_ra_used = 1;
+ cl_page_export(env, page, 1);
+ }
+
+ cl_2queue_init(queue);
+ /*
+ * Add page into the queue even when it is marked uptodate above.
+ * this will unlock it automatically as part of cl_page_list_disown().
+ */
+ cl_page_list_add(&queue->c2_qin, 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,
+ vpg->vpg_defer_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 cl_object *clob = ll_i2info(file_inode(file))->lli_clob;
@@ -1110,7 +1154,7 @@ int ll_readpage(struct file *file, struct page *vmpage)
LASSERT(page->cp_type == CPT_CACHEABLE);
if (likely(!PageUptodate(vmpage))) {
cl_page_assume(env, io, page);
- result = cl_io_read_page(env, io, page);
+ result = ll_io_read_page(env, io, page);
} else {
/* Page from a non-object file. */
unlock_page(vmpage);
diff --git a/drivers/staging/lustre/lustre/llite/vvp_io.c b/drivers/staging/lustre/lustre/llite/vvp_io.c
index dbc4c26..8187fa3 100644
--- a/drivers/staging/lustre/lustre/llite/vvp_io.c
+++ b/drivers/staging/lustre/lustre/llite/vvp_io.c
@@ -1228,40 +1228,23 @@ static int vvp_io_fsync_start(const struct lu_env *env,
return 0;
}

-static int vvp_io_read_page(const struct lu_env *env,
- const struct cl_io_slice *ios,
- const struct cl_page_slice *slice)
+static int vvp_io_read_ahead(const struct lu_env *env,
+ const struct cl_io_slice *ios,
+ pgoff_t start, struct cl_read_ahead *ra)
{
- struct cl_io *io = ios->cis_io;
- struct vvp_page *vpg = cl2vvp_page(slice);
- struct cl_page *page = slice->cpl_page;
- struct inode *inode = vvp_object_inode(slice->cpl_obj);
- struct ll_sb_info *sbi = ll_i2sbi(inode);
- struct ll_file_data *fd = cl2vvp_io(env, ios)->vui_fd;
- struct ll_readahead_state *ras = &fd->fd_ras;
- struct cl_2queue *queue = &io->ci_queue;
-
- if (sbi->ll_ra_info.ra_max_pages_per_file &&
- sbi->ll_ra_info.ra_max_pages)
- ras_update(sbi, inode, ras, vvp_index(vpg),
- vpg->vpg_defer_uptodate);
-
- if (vpg->vpg_defer_uptodate) {
- vpg->vpg_ra_used = 1;
- cl_page_export(env, page, 1);
- }
- /*
- * Add page into the queue even when it is marked uptodate above.
- * this will unlock it automatically as part of cl_page_list_disown().
- */
+ int result = 0;

- cl_page_list_add(&queue->c2_qin, page);
- if (sbi->ll_ra_info.ra_max_pages_per_file &&
- sbi->ll_ra_info.ra_max_pages)
- ll_readahead(env, io, &queue->c2_qin, ras,
- vpg->vpg_defer_uptodate);
+ if (ios->cis_io->ci_type == CIT_READ ||
+ ios->cis_io->ci_type == CIT_FAULT) {
+ struct vvp_io *vio = cl2vvp_io(env, ios);

- return 0;
+ if (unlikely(vio->vui_fd->fd_flags & LL_FILE_GROUP_LOCKED)) {
+ ra->cra_end = CL_PAGE_EOF;
+ result = 1; /* no need to call down */
+ }
+ }
+
+ return result;
}

static void vvp_io_end(const struct lu_env *env, const struct cl_io_slice *ios)
@@ -1308,7 +1291,7 @@ static const struct cl_io_operations vvp_io_ops = {
.cio_fini = vvp_io_fini
}
},
- .cio_read_page = vvp_io_read_page,
+ .cio_read_ahead = vvp_io_read_ahead,
};

int vvp_io_init(const struct lu_env *env, struct cl_object *obj,
diff --git a/drivers/staging/lustre/lustre/llite/vvp_page.c b/drivers/staging/lustre/lustre/llite/vvp_page.c
index 68f8990..75cec23 100644
--- a/drivers/staging/lustre/lustre/llite/vvp_page.c
+++ b/drivers/staging/lustre/lustre/llite/vvp_page.c
@@ -342,20 +342,6 @@ static int vvp_page_make_ready(const struct lu_env *env,
return result;
}

-static int vvp_page_is_under_lock(const struct lu_env *env,
- const struct cl_page_slice *slice,
- struct cl_io *io, pgoff_t *max_index)
-{
- if (io->ci_type == CIT_READ || io->ci_type == CIT_WRITE ||
- io->ci_type == CIT_FAULT) {
- struct vvp_io *vio = vvp_env_io(env);
-
- if (unlikely(vio->vui_fd->fd_flags & LL_FILE_GROUP_LOCKED))
- *max_index = CL_PAGE_EOF;
- }
- return 0;
-}
-
static int vvp_page_print(const struct lu_env *env,
const struct cl_page_slice *slice,
void *cookie, lu_printer_t printer)
@@ -400,7 +386,6 @@ static const struct cl_page_operations vvp_page_ops = {
.cpo_is_vmlocked = vvp_page_is_vmlocked,
.cpo_fini = vvp_page_fini,
.cpo_print = vvp_page_print,
- .cpo_is_under_lock = vvp_page_is_under_lock,
.io = {
[CRT_READ] = {
.cpo_prep = vvp_page_prep_read,
@@ -499,7 +484,6 @@ static const struct cl_page_operations vvp_transient_page_ops = {
.cpo_fini = vvp_transient_page_fini,
.cpo_is_vmlocked = vvp_transient_page_is_vmlocked,
.cpo_print = vvp_page_print,
- .cpo_is_under_lock = vvp_page_is_under_lock,
.io = {
[CRT_READ] = {
.cpo_prep = vvp_transient_page_prep,
diff --git a/drivers/staging/lustre/lustre/lov/lov_io.c b/drivers/staging/lustre/lustre/lov/lov_io.c
index d101579..e75e5d2 100644
--- a/drivers/staging/lustre/lustre/lov/lov_io.c
+++ b/drivers/staging/lustre/lustre/lov/lov_io.c
@@ -555,6 +555,63 @@ static void lov_io_unlock(const struct lu_env *env,
LASSERT(rc == 0);
}

+static int lov_io_read_ahead(const struct lu_env *env,
+ const struct cl_io_slice *ios,
+ pgoff_t start, struct cl_read_ahead *ra)
+{
+ struct lov_io *lio = cl2lov_io(env, ios);
+ struct lov_object *loo = lio->lis_object;
+ struct cl_object *obj = lov2cl(loo);
+ struct lov_layout_raid0 *r0 = lov_r0(loo);
+ unsigned int pps; /* pages per stripe */
+ struct lov_io_sub *sub;
+ pgoff_t ra_end;
+ loff_t suboff;
+ int stripe;
+ int rc;
+
+ stripe = lov_stripe_number(loo->lo_lsm, cl_offset(obj, start));
+ if (unlikely(!r0->lo_sub[stripe]))
+ return -EIO;
+
+ sub = lov_sub_get(env, lio, stripe);
+
+ lov_stripe_offset(loo->lo_lsm, cl_offset(obj, start), stripe, &suboff);
+ rc = cl_io_read_ahead(sub->sub_env, sub->sub_io,
+ cl_index(lovsub2cl(r0->lo_sub[stripe]), suboff),
+ ra);
+ lov_sub_put(sub);
+
+ CDEBUG(D_READA, DFID " cra_end = %lu, stripes = %d, rc = %d\n",
+ PFID(lu_object_fid(lov2lu(loo))), ra->cra_end, r0->lo_nr, rc);
+ if (rc)
+ return rc;
+
+ /**
+ * Adjust the stripe index by layout of raid0. ra->cra_end is
+ * the maximum page index covered by an underlying DLM lock.
+ * This function converts cra_end from stripe level to file
+ * level, and make sure it's not beyond stripe boundary.
+ */
+ if (r0->lo_nr == 1) /* single stripe file */
+ return 0;
+
+ /* cra_end is stripe level, convert it into file level */
+ ra_end = ra->cra_end;
+ if (ra_end != CL_PAGE_EOF)
+ ra_end = lov_stripe_pgoff(loo->lo_lsm, ra_end, stripe);
+
+ pps = loo->lo_lsm->lsm_stripe_size >> PAGE_SHIFT;
+
+ CDEBUG(D_READA, DFID " max_index = %lu, pps = %u, stripe_size = %u, stripe no = %u, start index = %lu\n",
+ PFID(lu_object_fid(lov2lu(loo))), ra_end, pps,
+ loo->lo_lsm->lsm_stripe_size, stripe, start);
+
+ /* never exceed the end of the stripe */
+ ra->cra_end = min_t(pgoff_t, ra_end, start + pps - start % pps - 1);
+ return 0;
+}
+
/**
* lov implementation of cl_operations::cio_submit() method. It takes a list
* of pages in \a queue, splits it into per-stripe sub-lists, invokes
@@ -801,6 +858,7 @@ static const struct cl_io_operations lov_io_ops = {
.cio_fini = lov_io_fini
}
},
+ .cio_read_ahead = lov_io_read_ahead,
.cio_submit = lov_io_submit,
.cio_commit_async = lov_io_commit_async,
};
diff --git a/drivers/staging/lustre/lustre/lov/lov_page.c b/drivers/staging/lustre/lustre/lov/lov_page.c
index 00bfaba..62ceb6d 100644
--- a/drivers/staging/lustre/lustre/lov/lov_page.c
+++ b/drivers/staging/lustre/lustre/lov/lov_page.c
@@ -49,51 +49,6 @@
*
*/

-/**
- * Adjust the stripe index by layout of raid0. @max_index is the maximum
- * page index covered by an underlying DLM lock.
- * This function converts max_index from stripe level to file level, and make
- * sure it's not beyond one stripe.
- */
-static int lov_raid0_page_is_under_lock(const struct lu_env *env,
- const struct cl_page_slice *slice,
- struct cl_io *unused,
- pgoff_t *max_index)
-{
- struct lov_object *loo = cl2lov(slice->cpl_obj);
- struct lov_layout_raid0 *r0 = lov_r0(loo);
- pgoff_t index = *max_index;
- unsigned int pps; /* pages per stripe */
-
- CDEBUG(D_READA, DFID "*max_index = %lu, nr = %d\n",
- PFID(lu_object_fid(lov2lu(loo))), index, r0->lo_nr);
-
- if (index == 0) /* the page is not covered by any lock */
- return 0;
-
- if (r0->lo_nr == 1) /* single stripe file */
- return 0;
-
- /* max_index is stripe level, convert it into file level */
- if (index != CL_PAGE_EOF) {
- int stripeno = lov_page_stripe(slice->cpl_page);
- *max_index = lov_stripe_pgoff(loo->lo_lsm, index, stripeno);
- }
-
- /* calculate the end of current stripe */
- pps = loo->lo_lsm->lsm_stripe_size >> PAGE_SHIFT;
- index = slice->cpl_index + pps - slice->cpl_index % pps - 1;
-
- CDEBUG(D_READA, DFID "*max_index = %lu, index = %lu, pps = %u, stripe_size = %u, stripe no = %u, page index = %lu\n",
- PFID(lu_object_fid(lov2lu(loo))), *max_index, index, pps,
- loo->lo_lsm->lsm_stripe_size, lov_page_stripe(slice->cpl_page),
- slice->cpl_index);
-
- /* never exceed the end of the stripe */
- *max_index = min_t(pgoff_t, *max_index, index);
- return 0;
-}
-
static int lov_raid0_page_print(const struct lu_env *env,
const struct cl_page_slice *slice,
void *cookie, lu_printer_t printer)
@@ -104,7 +59,6 @@ static int lov_raid0_page_print(const struct lu_env *env,
}

static const struct cl_page_operations lov_raid0_page_ops = {
- .cpo_is_under_lock = lov_raid0_page_is_under_lock,
.cpo_print = lov_raid0_page_print
};

diff --git a/drivers/staging/lustre/lustre/obdclass/cl_io.c b/drivers/staging/lustre/lustre/obdclass/cl_io.c
index bc4b7b6..577f76e 100644
--- a/drivers/staging/lustre/lustre/obdclass/cl_io.c
+++ b/drivers/staging/lustre/lustre/obdclass/cl_io.c
@@ -586,67 +586,32 @@ void cl_io_end(const struct lu_env *env, struct cl_io *io)
}
EXPORT_SYMBOL(cl_io_end);

-static const struct cl_page_slice *
-cl_io_slice_page(const struct cl_io_slice *ios, struct cl_page *page)
-{
- const struct cl_page_slice *slice;
-
- slice = cl_page_at(page, ios->cis_obj->co_lu.lo_dev->ld_type);
- LINVRNT(slice);
- return slice;
-}
-
/**
- * Called by read io, when page has to be read from the server.
+ * Called by read io, to decide the readahead extent
*
- * \see cl_io_operations::cio_read_page()
+ * \see cl_io_operations::cio_read_ahead()
*/
-int cl_io_read_page(const struct lu_env *env, struct cl_io *io,
- struct cl_page *page)
+int cl_io_read_ahead(const struct lu_env *env, struct cl_io *io,
+ pgoff_t start, struct cl_read_ahead *ra)
{
const struct cl_io_slice *scan;
- struct cl_2queue *queue;
int result = 0;

LINVRNT(io->ci_type == CIT_READ || io->ci_type == CIT_FAULT);
- LINVRNT(cl_page_is_owned(page, io));
LINVRNT(io->ci_state == CIS_IO_GOING || io->ci_state == CIS_LOCKED);
LINVRNT(cl_io_invariant(io));

- queue = &io->ci_queue;
-
- cl_2queue_init(queue);
- /*
- * ->cio_read_page() methods called in the loop below are supposed to
- * never block waiting for network (the only subtle point is the
- * creation of new pages for read-ahead that might result in cache
- * shrinking, but currently only clean pages are shrunk and this
- * requires no network io).
- *
- * Should this ever starts blocking, retry loop would be needed for
- * "parallel io" (see CLO_REPEAT loops in cl_lock.c).
- */
cl_io_for_each(scan, io) {
- if (scan->cis_iop->cio_read_page) {
- const struct cl_page_slice *slice;
+ if (!scan->cis_iop->cio_read_ahead)
+ continue;

- slice = cl_io_slice_page(scan, page);
- LINVRNT(slice);
- result = scan->cis_iop->cio_read_page(env, scan, slice);
- if (result != 0)
- break;
- }
+ result = scan->cis_iop->cio_read_ahead(env, scan, start, ra);
+ if (result)
+ break;
}
- if (result == 0 && queue->c2_qin.pl_nr > 0)
- result = 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 result;
+ return result > 0 ? 0 : result;
}
-EXPORT_SYMBOL(cl_io_read_page);
+EXPORT_SYMBOL(cl_io_read_ahead);

/**
* Commit a list of contiguous pages into writeback cache.
diff --git a/drivers/staging/lustre/lustre/obdclass/cl_page.c b/drivers/staging/lustre/lustre/obdclass/cl_page.c
index 63973ba..40b7bee 100644
--- a/drivers/staging/lustre/lustre/obdclass/cl_page.c
+++ b/drivers/staging/lustre/lustre/obdclass/cl_page.c
@@ -390,30 +390,6 @@ EXPORT_SYMBOL(cl_page_at);
__result; \
})

-#define CL_PAGE_INVOKE_REVERSE(_env, _page, _op, _proto, ...) \
-({ \
- const struct lu_env *__env = (_env); \
- struct cl_page *__page = (_page); \
- const struct cl_page_slice *__scan; \
- int __result; \
- ptrdiff_t __op = (_op); \
- int (*__method)_proto; \
- \
- __result = 0; \
- list_for_each_entry_reverse(__scan, &__page->cp_layers, \
- cpl_linkage) { \
- __method = *(void **)((char *)__scan->cpl_ops + __op); \
- if (__method) { \
- __result = (*__method)(__env, __scan, ## __VA_ARGS__); \
- if (__result != 0) \
- break; \
- } \
- } \
- if (__result > 0) \
- __result = 0; \
- __result; \
-})
-
#define CL_PAGE_INVOID(_env, _page, _op, _proto, ...) \
do { \
const struct lu_env *__env = (_env); \
@@ -927,29 +903,6 @@ int cl_page_flush(const struct lu_env *env, struct cl_io *io,
EXPORT_SYMBOL(cl_page_flush);

/**
- * Checks whether page is protected by any extent lock is at least required
- * mode.
- *
- * \return the same as in cl_page_operations::cpo_is_under_lock() method.
- * \see cl_page_operations::cpo_is_under_lock()
- */
-int cl_page_is_under_lock(const struct lu_env *env, struct cl_io *io,
- struct cl_page *page, pgoff_t *max_index)
-{
- int rc;
-
- PINVRNT(env, page, cl_page_invariant(page));
-
- rc = CL_PAGE_INVOKE_REVERSE(env, page, CL_PAGE_OP(cpo_is_under_lock),
- (const struct lu_env *,
- const struct cl_page_slice *,
- struct cl_io *, pgoff_t *),
- io, max_index);
- return rc;
-}
-EXPORT_SYMBOL(cl_page_is_under_lock);
-
-/**
* Tells transfer engine that only part of a page is to be transmitted.
*
* \see cl_page_operations::cpo_clip()
diff --git a/drivers/staging/lustre/lustre/osc/osc_cache.c b/drivers/staging/lustre/lustre/osc/osc_cache.c
index 4bbe219..b645957 100644
--- a/drivers/staging/lustre/lustre/osc/osc_cache.c
+++ b/drivers/staging/lustre/lustre/osc/osc_cache.c
@@ -3158,7 +3158,8 @@ static int check_and_discard_cb(const struct lu_env *env, struct cl_io *io,
struct cl_page *page = ops->ops_cl.cpl_page;

/* refresh non-overlapped index */
- tmp = osc_dlmlock_at_pgoff(env, osc, index, 0, 0);
+ tmp = osc_dlmlock_at_pgoff(env, osc, index,
+ OSC_DAP_FL_TEST_LOCK);
if (tmp) {
__u64 end = tmp->l_policy_data.l_extent.end;
/* Cache the first-non-overlapped index so as to skip
diff --git a/drivers/staging/lustre/lustre/osc/osc_internal.h b/drivers/staging/lustre/lustre/osc/osc_internal.h
index 67fe0a2..9a61c9b 100644
--- a/drivers/staging/lustre/lustre/osc/osc_internal.h
+++ b/drivers/staging/lustre/lustre/osc/osc_internal.h
@@ -199,8 +199,23 @@ void osc_inc_unstable_pages(struct ptlrpc_request *req);
void osc_dec_unstable_pages(struct ptlrpc_request *req);
bool osc_over_unstable_soft_limit(struct client_obd *cli);

+/**
+ * Bit flags for osc_dlm_lock_at_pageoff().
+ */
+enum osc_dap_flags {
+ /**
+ * Just check if the desired lock exists, it won't hold reference
+ * count on lock.
+ */
+ OSC_DAP_FL_TEST_LOCK = BIT(0),
+ /**
+ * Return the lock even if it is being canceled.
+ */
+ OSC_DAP_FL_CANCELING = BIT(1),
+};
+
struct ldlm_lock *osc_dlmlock_at_pgoff(const struct lu_env *env,
struct osc_object *obj, pgoff_t index,
- int pending, int canceling);
+ enum osc_dap_flags flags);

#endif /* OSC_INTERNAL_H */
diff --git a/drivers/staging/lustre/lustre/osc/osc_io.c b/drivers/staging/lustre/lustre/osc/osc_io.c
index 8a559cb..47c6371 100644
--- a/drivers/staging/lustre/lustre/osc/osc_io.c
+++ b/drivers/staging/lustre/lustre/osc/osc_io.c
@@ -88,6 +88,44 @@ static void osc_io_fini(const struct lu_env *env, const struct cl_io_slice *io)
{
}

+static void osc_read_ahead_release(const struct lu_env *env, void *cbdata)
+{
+ struct ldlm_lock *dlmlock = cbdata;
+ struct lustre_handle lockh;
+
+ ldlm_lock2handle(dlmlock, &lockh);
+ ldlm_lock_decref(&lockh, LCK_PR);
+ LDLM_LOCK_PUT(dlmlock);
+}
+
+static int osc_io_read_ahead(const struct lu_env *env,
+ const struct cl_io_slice *ios,
+ pgoff_t start, struct cl_read_ahead *ra)
+{
+ struct osc_object *osc = cl2osc(ios->cis_obj);
+ struct ldlm_lock *dlmlock;
+ int result = -ENODATA;
+
+ dlmlock = osc_dlmlock_at_pgoff(env, osc, start, 0);
+ if (dlmlock) {
+ if (dlmlock->l_req_mode != LCK_PR) {
+ struct lustre_handle lockh;
+
+ ldlm_lock2handle(dlmlock, &lockh);
+ ldlm_lock_addref(&lockh, LCK_PR);
+ ldlm_lock_decref(&lockh, dlmlock->l_req_mode);
+ }
+
+ ra->cra_end = cl_index(osc2cl(osc),
+ dlmlock->l_policy_data.l_extent.end);
+ ra->cra_release = osc_read_ahead_release;
+ ra->cra_cbdata = dlmlock;
+ result = 0;
+ }
+
+ return result;
+}
+
/**
* An implementation of cl_io_operations::cio_io_submit() method for osc
* layer. Iterates over pages in the in-queue, prepares each for io by calling
@@ -724,6 +762,7 @@ static const struct cl_io_operations osc_io_ops = {
.cio_fini = osc_io_fini
}
},
+ .cio_read_ahead = osc_io_read_ahead,
.cio_submit = osc_io_submit,
.cio_commit_async = osc_io_commit_async
};
@@ -798,7 +837,7 @@ static void osc_req_attr_set(const struct lu_env *env,
struct cl_page, cp_flight);
opg = osc_cl_page_osc(apage, NULL);
lock = osc_dlmlock_at_pgoff(env, cl2osc(obj), osc_index(opg),
- 1, 1);
+ OSC_DAP_FL_TEST_LOCK | OSC_DAP_FL_CANCELING);
if (!lock && !opg->ops_srvlock) {
struct ldlm_resource *res;
struct ldlm_res_id *resname;
diff --git a/drivers/staging/lustre/lustre/osc/osc_lock.c b/drivers/staging/lustre/lustre/osc/osc_lock.c
index 39a8a58..a42cb98 100644
--- a/drivers/staging/lustre/lustre/osc/osc_lock.c
+++ b/drivers/staging/lustre/lustre/osc/osc_lock.c
@@ -1180,7 +1180,7 @@ int osc_lock_init(const struct lu_env *env,
*/
struct ldlm_lock *osc_dlmlock_at_pgoff(const struct lu_env *env,
struct osc_object *obj, pgoff_t index,
- int pending, int canceling)
+ enum osc_dap_flags dap_flags)
{
struct osc_thread_info *info = osc_env_info(env);
struct ldlm_res_id *resname = &info->oti_resname;
@@ -1194,9 +1194,10 @@ struct ldlm_lock *osc_dlmlock_at_pgoff(const struct lu_env *env,
osc_index2policy(policy, osc2cl(obj), index, index);
policy->l_extent.gid = LDLM_GID_ANY;

- flags = LDLM_FL_BLOCK_GRANTED | LDLM_FL_TEST_LOCK;
- if (pending)
- flags |= LDLM_FL_CBPENDING;
+ flags = LDLM_FL_BLOCK_GRANTED | LDLM_FL_CBPENDING;
+ if (dap_flags & OSC_DAP_FL_TEST_LOCK)
+ flags |= LDLM_FL_TEST_LOCK;
+
/*
* It is fine to match any group lock since there could be only one
* with a uniq gid and it conflicts with all other lock modes too
@@ -1204,7 +1205,8 @@ struct ldlm_lock *osc_dlmlock_at_pgoff(const struct lu_env *env,
again:
mode = ldlm_lock_match(osc_export(obj)->exp_obd->obd_namespace,
flags, resname, LDLM_EXTENT, policy,
- LCK_PR | LCK_PW | LCK_GROUP, &lockh, canceling);
+ LCK_PR | LCK_PW | LCK_GROUP, &lockh,
+ dap_flags & OSC_DAP_FL_CANCELING);
if (mode != 0) {
lock = ldlm_handle2lock(&lockh);
/* RACE: the lock is cancelled so let's try again */
diff --git a/drivers/staging/lustre/lustre/osc/osc_page.c b/drivers/staging/lustre/lustre/osc/osc_page.c
index 2a7a70a..399d36b 100644
--- a/drivers/staging/lustre/lustre/osc/osc_page.c
+++ b/drivers/staging/lustre/lustre/osc/osc_page.c
@@ -117,25 +117,6 @@ void osc_index2policy(ldlm_policy_data_t *policy, const struct cl_object *obj,
policy->l_extent.end = cl_offset(obj, end + 1) - 1;
}

-static int osc_page_is_under_lock(const struct lu_env *env,
- const struct cl_page_slice *slice,
- struct cl_io *unused, pgoff_t *max_index)
-{
- struct osc_page *opg = cl2osc_page(slice);
- struct ldlm_lock *dlmlock;
- int result = -ENODATA;
-
- dlmlock = osc_dlmlock_at_pgoff(env, cl2osc(slice->cpl_obj),
- osc_index(opg), 1, 0);
- if (dlmlock) {
- *max_index = cl_index(slice->cpl_obj,
- dlmlock->l_policy_data.l_extent.end);
- LDLM_LOCK_PUT(dlmlock);
- result = 0;
- }
- return result;
-}
-
static const char *osc_list(struct list_head *head)
{
return list_empty(head) ? "-" : "+";
@@ -276,7 +257,6 @@ static int osc_page_flush(const struct lu_env *env,
static const struct cl_page_operations osc_page_ops = {
.cpo_print = osc_page_print,
.cpo_delete = osc_page_delete,
- .cpo_is_under_lock = osc_page_is_under_lock,
.cpo_clip = osc_page_clip,
.cpo_cancel = osc_page_cancel,
.cpo_flush = osc_page_flush
--
1.7.1