On Mon, Aug 26, 2019 at 01:48:32PM +0200, Johannes Thumshirn wrote: > Create a structure to encode the type and length for the known on-disk > checksums. > > This makes it easier to add new checksums later. > > Signed-off-by: Johannes Thumshirn <[email protected]> > > --- > Changes to v2: > - Really remove initializer macro *doh* > > Changes to v1: > - Remove initializer macro (David) > --- > fs/btrfs/ctree.h | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > index b161224b5a0b..139354d02dfa 100644 > --- a/fs/btrfs/ctree.h > +++ b/fs/btrfs/ctree.h > @@ -82,9 +82,12 @@ struct btrfs_ref; > */ > #define BTRFS_LINK_MAX 65535U > > -/* four bytes for CRC32 */ > -static const int btrfs_csum_sizes[] = { 4 }; > -static const char *btrfs_csum_names[] = { "crc32c" }; > +static const struct btrfs_csums { > + u16 size; > + const char *name; > +} btrfs_csums[] = { > + [BTRFS_CSUM_TYPE_CRC32] = { .size = 4, .name = "crc32c" }, > +};
In one of the previous iterations, I pointed out that the definition is in a header, thus each file that includes "ctree.h" (many of them) has a private copy of the table. With just crc32c it's just a few bytes that gets lost in the noise but now the table is going to be larger the impact will be noticeable.
