Branch HEAD

Add description of the patch.

diff --git a/lustre/kernel_patches/patches/dev_read_only-2.6.22-vanilla.patch b/lustre/kernel_patches/patches/dev_read_only-2.6.22-vanilla.patch
index a6e7351..e7e40ac 100644 (file)
--- a/lustre/kernel_patches/patches/dev_read_only-2.6.22-vanilla.patch
+++ b/lustre/kernel_patches/patches/dev_read_only-2.6.22-vanilla.patch
@@ -1,3 +1,11 @@
+Set the underlying block device "read only" and silently discard writes
+to the device at the block layer.  This allows the block device queue
+to drain quickly for controlled failback of the device.
+
+At one time it was required to avoid crashes in the JBD layer during
+failover, but it may also be possible to just allow the inflight IO to
+complete and have Lustre handle this more gracefully.
+
 diff -urp linux-2.6.18.1.orig/block/ll_rw_blk.c linux-2.6.18.1/block/ll_rw_blk.c
 --- linux-2.6.18.1.orig/block/ll_rw_blk.c      2006-10-14 06:34:03.000000000 +0300
 +++ linux-2.6.18.1/block/ll_rw_blk.c   2007-05-29 14:50:46.000000000 +0300

diff --git a/lustre/kernel_patches/patches/export-2.6.18-vanilla.patch b/lustre/kernel_patches/patches/export-2.6.18-vanilla.patch
index a6813e6..9727ea4 100644 (file)
--- a/lustre/kernel_patches/patches/export-2.6.18-vanilla.patch
+++ b/lustre/kernel_patches/patches/export-2.6.18-vanilla.patch
@@ -1,15 +1,8 @@
-Index: linux-2.6/fs/open.c
-===================================================================
---- linux-2.6.orig/fs/open.c   2006-07-15 16:10:37.000000000 +0800
-+++ linux-2.6/fs/open.c        2006-07-15 16:22:04.000000000 +0800
-@@ -808,7 +808,6 @@ asmlinkage long sys_lchown(const char __
-       return error;
- }
- 
--
- asmlinkage long sys_fchown(unsigned int fd, uid_t user, gid_t group)
- {
-       struct file * file;
+Allow starting the commit of a journal transaction, without waiting for
+it to complete.  This is a performance enhancement for OST IO so that
+the journal commit can run concurrently with the file IO.  It isn't
+necessary if the client can handle bulk IO recovery (bug 16919).
+
 Index: linux-2.6/fs/jbd/journal.c
 ===================================================================
 --- linux-2.6.orig/fs/jbd/journal.c    2006-07-15 16:13:50.000000000 +0800

diff --git a/lustre/kernel_patches/patches/export-show_task-2.6.18-vanilla.patch b/lustre/kernel_patches/patches/export-show_task-2.6.18-vanilla.patch
index 834c886..a01aaaf 100644 (file)
--- a/lustre/kernel_patches/patches/export-show_task-2.6.18-vanilla.patch
+++ b/lustre/kernel_patches/patches/export-show_task-2.6.18-vanilla.patch
@@ -1,3 +1,8 @@
+Export the show_task() function in order to get better process stacks.
+It will also print the current process stack, which is useful.
+
+This is a nice-to-have but not required for Lustre to work.
+
 Index: linux-2.6/kernel/sched.c
 ===================================================================
 --- linux-2.6.orig/kernel/sched.c      2006-07-15 11:51:46.000000000 +0800