Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [PATCH 02/16] f2fs: add on-disk layout | Date | Fri, 12 Oct 2012 21:05:08 +0000 |
| |
On Friday 05 October 2012 20:56:44 김재극 wrote: > +struct f2fs_nat_entry { > + __u8 version; > + __le32 ino; > + __le32 block_addr; > +} __packed; > + > +struct f2fs_nat_block { > + struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK]; > +} __packed;
Using "__packed" on structure is rather inefficient on CPU architectures that cannot do aligned accesses. I would suggest you remove this attribute everywhere you can. The f2fs_nat_entry is particularly suboptimal because it is 9 bytes long, and I'm not sure if this can be reasonably changed to a multiple of four.
In all other cases, you should try to lay out the structures so that each member is naturally aligned and you don't need any __packed attributes, in particular for those that are accessed a lot.
Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |