xfs: kill XBF_DONTBLOCK

Just about all callers of xfs_buf_read() and xfs_buf_get() use XBF_DONTBLOCK.
This is used to make memory allocation use GFP_NOFS rather than GFP_KERNEL to
avoid recursion through memory reclaim back into the filesystem.

All the blocking get calls in growfs occur inside a transaction, even though
they are no part of the transaction, so all allocation will be GFP_NOFS due to
the task flag PF_TRANS being set. The blocking read calls occur during log
recovery, so they will probably be unaffected by converting to GFP_NOFS
allocations.

Hence make XBF_DONTBLOCK behaviour always occur for buffers and kill the flag.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
This commit is contained in:
Dave Chinner
2012-04-23 15:58:56 +10:00
committed by Ben Myers
parent 7ca790a507
commit aa5c158ec9
5 changed files with 14 additions and 38 deletions

View File

@@ -53,7 +53,6 @@ typedef enum {
/* flags used only as arguments to access routines */
#define XBF_TRYLOCK (1 << 16)/* lock requested, but do not wait */
#define XBF_DONT_BLOCK (1 << 17)/* do not block in current thread */
/* flags used only internally */
#define _XBF_PAGES (1 << 20)/* backed by refcounted pages */
@@ -74,7 +73,6 @@ typedef unsigned int xfs_buf_flags_t;
{ XBF_FUA, "FUA" }, \
{ XBF_FLUSH, "FLUSH" }, \
{ XBF_TRYLOCK, "TRYLOCK" }, /* should never be set */\
{ XBF_DONT_BLOCK, "DONT_BLOCK" }, /* ditto */\
{ _XBF_PAGES, "PAGES" }, \
{ _XBF_KMEM, "KMEM" }, \
{ _XBF_DELWRI_Q, "DELWRI_Q" }