Re: [PATCH 04/33] readahead: page flag PG_readahead

[Andrew Morton]

Wu Fengguang <wfg@xxxxxxxxxxxxxxxx> wrote:
>
> An new page flag PG_readahead is introduced as a look-ahead mark, which
> reminds the caller to give the adaptive read-ahead logic a chance to do
> read-ahead ahead of time for I/O pipelining.
> 
> It roughly corresponds to `ahead_start' of the stock read-ahead logic.
> 

This isn't a very revealing description of what this flag does.

> +#define __SetPageReadahead(page) __set_bit(PG_readahead, &(page)->flags)

uh-oh.  This is extremly risky.  Needs extensive justification, please.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/