diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c
old mode 100644
new mode 100755
index acd9264..69af326
--- a/lustre/llite/rw.c
+++ b/lustre/llite/rw.c
@@ -1115,6 +1115,25 @@ out:
static void ll_ra_stats_inc_sbi(struct ll_sb_info *sbi, enum ra_stat which);
+/* ra_io_arg will be filled in the beginning of ll_readahead with
+ * ras_lock, then the following ll_read_ahead_pages will read RA
+ * pages according to this arg, all the items in this structure are
+ * counted by page index.
+ */
+struct ra_io_arg {
+ unsigned long ria_start; /* start offset of read-ahead*/
+ unsigned long ria_end; /* end offset of read-ahead*/
+ /* If stride read pattern is detected, ria_stoff means where
+ * stride read is started. Note: for normal read-ahead, the
+ * value here is meaningless, and also it will not be accessed*/
+ pgoff_t ria_stoff;
+ /* ria_length and ria_pages are the length and pages length in the
+ * stride I/O mode. And they will also be used to check whether
+ * it is stride I/O read-ahead in the read-ahead pages*/
+ unsigned long ria_length;
+ unsigned long ria_pages;
+};
+
/* 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.
@@ -1125,25 +1144,40 @@ static void ll_ra_stats_inc_sbi(struct ll_sb_info *sbi, enum ra_stat which);
* 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)
+#define RA_WAIT_PAGES 0
+static unsigned long ll_ra_count_get(struct ll_sb_info *sbi, struct ra_io_arg *ria,
+ unsigned long len, obd_off read_end)
{
struct ll_ra_info *ra = &sbi->ll_ra_info;
unsigned long ret = 0;
ENTRY;
- /**
- * 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 - atomic_read(&ra->ra_cur_pages), len);
- if ((int)ret < min((unsigned long)PTLRPC_MAX_BRW_PAGES, len))
- GOTO(out, ret = 0);
+ if (ra->ra_max_pages > atomic_read(&ra->ra_cur_pages)) {
+ ret = min(ra->ra_max_pages - atomic_read(&ra->ra_cur_pages), len);
+ if ((int)ret < min((unsigned long)PTLRPC_MAX_BRW_PAGES, len))
+ GOTO(out, ret = 0);
+ }
+
+ if (ria->ria_pages == 0) {
+ if (ret >= ((ria->ria_start + ret) % PTLRPC_MAX_BRW_PAGES))
+ ret -= (ria->ria_start + ret) % PTLRPC_MAX_BRW_PAGES;
+ else
+ GOTO(out, ret = 0);
+ }
if (atomic_add_return(ret, &ra->ra_cur_pages) > ra->ra_max_pages) {
atomic_sub(ret, &ra->ra_cur_pages);
- ret = 0;
+ if (ria->ria_pages == 0) {
+ /* We should still read ahead until the end of syscall,
+ * otherwise the client will send single page RPC, which
+ * impact the performance even worse*/
+ atomic_add(read_end, &ra->ra_cur_pages);
+ ret = read_end;
+ } else {
+ ret = 0;
+ }
}
+
out:
RETURN(ret);
}
@@ -1420,7 +1454,7 @@ void ll_ra_read_ex(struct file *f, struct ll_ra_read *rar)
struct ll_readahead_state *ras;
ras = ll_ras_get(f);
-
+
spin_lock(&ras->ras_lock);
list_del_init(&rar->lrr_linkage);
spin_unlock(&ras->ras_lock);
@@ -1546,25 +1580,6 @@ unlock_page:
return rc;
}
-/* ra_io_arg will be filled in the beginning of ll_readahead with
- * ras_lock, then the following ll_read_ahead_pages will read RA
- * pages according to this arg, all the items in this structure are
- * counted by page index.
- */
-struct ra_io_arg {
- unsigned long ria_start; /* start offset of read-ahead*/
- unsigned long ria_end; /* end offset of read-ahead*/
- /* If stride read pattern is detected, ria_stoff means where
- * stride read is started. Note: for normal read-ahead, the
- * value here is meaningless, and also it will not be accessed*/
- pgoff_t ria_stoff;
- /* ria_length and ria_pages are the length and pages length in the
- * stride I/O mode. And they will also be used to check whether
- * it is stride I/O read-ahead in the read-ahead pages*/
- unsigned long ria_length;
- unsigned long ria_pages;
-};
-
#define RIA_DEBUG(ria) \
CDEBUG(D_READA, "rs %lu re %lu ro %lu rl %lu rp %lu\n", \
ria->ria_start, ria->ria_end, ria->ria_stoff, ria->ria_length,\
@@ -1773,6 +1788,7 @@ static int ll_readahead(struct ll_readahead_state *ras,
struct ll_ra_read *bead;
struct ost_lvb lvb;
struct ra_io_arg ria = { 0 };
+ obd_off read_end = 0;
int ret = 0;
__u64 kms;
ENTRY;
@@ -1832,7 +1848,7 @@ static int ll_readahead(struct ll_readahead_state *ras,
if (len == 0)
RETURN(0);
- reserved = ll_ra_count_get(ll_i2sbi(inode), len);
+ reserved = ll_ra_count_get(ll_i2sbi(inode), &ria, len, read_end);
if (reserved < len)
ll_ra_stats_inc(mapping, RA_STAT_MAX_IN_FLIGHT);
@@ -2033,7 +2049,7 @@ static void ras_increase_window(struct ll_readahead_state *ras,
else
ras->ras_window_len = min(ras->ras_window_len +
(unsigned long)step,
- ra->ra_max_pages);
+ ra->ra_max_pages_per_file);
}
static void ras_update(struct ll_sb_info *sbi, struct inode *inode,
@@ -2316,7 +2332,8 @@ int ll_readpage(struct file *filp, struct page *page)
GOTO(out, rc = PTR_ERR(llap));
}
- if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages_per_file)
+ if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages_per_file &&
+ ll_i2sbi(inode)->ll_ra_info.ra_max_pages)
ras_update(ll_i2sbi(inode), inode, &fd->fd_ras, page->index,
llap->llap_defer_uptodate);
@@ -2324,8 +2341,10 @@ int ll_readpage(struct file *filp, struct page *page)
if (llap->llap_defer_uptodate) {
/* This is the callpath if we got the page from a readahead */
llap->llap_ra_used = 1;
- rc = ll_readahead(&fd->fd_ras, exp, page->mapping, oig,
- fd->fd_flags);
+ if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages_per_file &&
+ ll_i2sbi(inode)->ll_ra_info.ra_max_pages)
+ rc = ll_readahead(&fd->fd_ras, exp, page->mapping, oig,
+ fd->fd_flags);
if (rc > 0)
obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd,
NULL, oig);
@@ -2342,12 +2361,12 @@ int ll_readpage(struct file *filp, struct page *page)
LL_CDEBUG_PAGE(D_PAGE, page, "queued readpage\n");
/* We have just requested the actual page we want, see if we can tack
* on some readahead to that page's RPC before it is sent. */
- if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages_per_file)
+ if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages_per_file &&
+ ll_i2sbi(inode)->ll_ra_info.ra_max_pages)
ll_readahead(&fd->fd_ras, exp, page->mapping, oig,
fd->fd_flags);
-
+
rc = obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd, NULL, oig);
-
out:
if (rc)
unlock_page(page);