X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fllite%2Frw.c;h=23093e12b4d97f18a81ce0661342c47231db7ac0;hp=9b2ecdd78446e257ced06a56f3477b034fd6e9d0;hb=9e4c5bdaaec5ef347260f0fd2f916143224f3cc4;hpb=01286ba81ce93e05e5e61c8346c80c74deb29d32

diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c
index 9b2ecdd..23093e12 100644
--- a/lustre/llite/rw.c
+++ b/lustre/llite/rw.c
@@ -1485,6 +1485,34 @@ static int kickoff_async_readahead(struct file *file, unsigned long pages)
 	return 2;
 }
 
+/*
+ * 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.
+ */
+static bool ll_use_fast_io(struct file *file,
+			   struct ll_readahead_state *ras, pgoff_t index)
+{
+	unsigned long fast_read_pages =
+		max(RA_REMAIN_WINDOW_MIN, ras->ras_rpc_pages);
+	loff_t skip_pages;
+
+	if (stride_io_mode(ras)) {
+		skip_pages = (ras->ras_stride_length +
+			ras->ras_stride_bytes - 1) / ras->ras_stride_bytes;
+		skip_pages *= fast_read_pages;
+	} else {
+		skip_pages = fast_read_pages;
+	}
+
+	if (ras->ras_window_start_idx + ras->ras_window_pages <
+	    ras->ras_next_readahead_idx + skip_pages ||
+	    kickoff_async_readahead(file, fast_read_pages) > 0)
+		return true;
+
+	return false;
+}
+
 int ll_readpage(struct file *file, struct page *vmpage)
 {
 	struct inode *inode = file_inode(file);
@@ -1508,8 +1536,6 @@ int ll_readpage(struct file *file, struct page *vmpage)
 		struct ll_file_data *fd = LUSTRE_FPRIVATE(file);
 		struct ll_readahead_state *ras = &fd->fd_ras;
 		struct lu_env  *local_env = NULL;
-		unsigned long fast_read_pages =
-			max(RA_REMAIN_WINDOW_MIN, ras->ras_rpc_pages);
 		struct vvp_page *vpg;
 
 		result = -ENODATA;
@@ -1537,12 +1563,7 @@ int ll_readpage(struct file *file, struct page *vmpage)
 			/* 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_idx + ras->ras_window_pages <
-			    ras->ras_next_readahead_idx + fast_read_pages ||
-			    kickoff_async_readahead(file, fast_read_pages) > 0)
+			if (ll_use_fast_io(file, ras, vvp_index(vpg)))
 				result = 0;
 		}