On Fri, 8 Jun 2007 12:48:48 +1000 Neil Brown <[EMAIL PROTECTED]> wrote:
> The following patch will remove the extra seqlock except when we > actually need it and remove the extra arithmetic - but I haven't > tested it or reviewed it properly. I can do that if you think it is > the right direction. Yes, the optimisation is valid and looks useful. > ./mm/filemap.c | 34 ++++++++++++++++++++++++++++------ It didn't apply - your tree seems different from mine. > + * > + * NOTE: This access of inode->i_size is not protected > + * and if there is a concurrent update on a 32bit machine, > + * it could return the wrong value. This could only be a > problem > + * if i_size has actually changed to a smaller value before the > + * page became uptodate, and at this point it still has a > smaller > + * value, but due to a race while reading, it appears > unchanged. > + * The chances of this happening are so small and the > consequence > + * sufficiently minor, that the cost of the seqlock seems > + * not to be justified. please consider incorporating scripts/checkpatch.pl into your patch preparation toolchain. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/