[PATCH] make the page allocator aware of filesystem transactions

[Christoph Hellwig <hch@lst.de>]

In XFS we have large pieces of code that might be called either from
inside a filesystem transaction or not.  Currently we have added a
PF_FSTRANS process flag and fall back to GFP_NOFS when it's set.

I think it might be useful to generalize this at the page allocator
level and always clear __GFP_FS if the process flag is set.

Comments?


You can import this changeset into BK by piping this whole message to:
'| bk receive [path to repository]' or apply the patch as usual.

===================================================================


ChangeSet@1.509, 2002-08-23 22:01:27+02:00, hch@sb.bsdonline.org
  VM: make the page allocator aware of filesystem transactions


 include/linux/sched.h |    1 +
 mm/vmscan.c           |    3 +++
 2 files changed, 4 insertions


diff -Nru a/include/linux/sched.h b/include/linux/sched.h
--- a/include/linux/sched.h	Fri Aug 23 22:01:58 2002
+++ b/include/linux/sched.h	Fri Aug 23 22:01:58 2002
@@ -400,6 +400,7 @@
 #define PF_FREEZE	0x00010000	/* this task should be frozen for suspend */
 #define PF_IOTHREAD	0x00020000	/* this thread is needed for doing I/O to swap */
 #define PF_FROZEN	0x00040000	/* frozen for system suspend */
+#define PF_FSTRANS	0x00080000	/* inside a filesystem transaction */
 
 /*
  * Ptrace flags
diff -Nru a/mm/vmscan.c b/mm/vmscan.c
--- a/mm/vmscan.c	Fri Aug 23 22:01:58 2002
+++ b/mm/vmscan.c	Fri Aug 23 22:01:58 2002
@@ -458,6 +458,9 @@
 	int max_scan;
 	static atomic_t nr_to_refill = ATOMIC_INIT(0);
 
+	if (current->flags & PF_FSTRANS)
+		gfp_mask &= ~__GFP_FS;
+
 	if (kmem_cache_reap(gfp_mask) >= nr_pages)
   		return 0;
 

===================================================================


This BitKeeper patch contains the following changesets:
1.509
## Wrapped with gzip_uu ##


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