Re: [RFC] mballoc patches

[Eric Sandeen <sandeen@redhat.com>]

Aneesh Kumar K.V wrote:
> 
> 
> I am attaching below the PATCH 2/4 in .gz format. The uncompressed one
> got dropped by the list.
> 
> -aneesh

hmm makes it hard to comment in-line though :)  So basing this on the
patch currently in the git repo.

+/*
+ * default stripe size = 1MB
+ */
+#define MB_DEFAULT_STRIPE              256

Units?  Doesn't seem to matter anyway as it's never referenced.

+       /* tunables */
+       unsigned long s_mb_factor;
+       unsigned long s_stripe;
+       unsigned long s_mb_small_req;
+       unsigned long s_mb_large_req;
+       unsigned long s_mb_max_to_scan;
+       unsigned long s_mb_min_to_scan;

could we get some comments here as to what these are, and what units?

Same is true many places... for example

+static int mb_find_extent(struct ext4_buddy *e3b, int order, int block,
+                               int needed, struct ext4_free_extent *ex)

how many "what" are needed?

And perhaps an addition of the new mount options to
Documentation/fs/ext4.txt would be good.

+#define EXT4_MB_BITMAP(e3b)    ((e3b)->bd_bitmap)
+#define EXT4_MB_BUDDY(e3b)     ((e3b)->bd_buddy)

For the sake of consistency should these (and others) be e4b?

Also there are a *lot* of BUGs and BUG_ONs added in this patch... are
none of these recoverable?

Thanks,

-Eric