From: Fengguang Wu Move the tiny I/O size protection code from limit_rala() to state_based_readahead(). limit_rala() is also called by context based readahead, which has its own minimal readahead size. Signed-off-by: Fengguang Wu Signed-off-by: Andrew Morton --- mm/readahead.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff -puN mm/readahead.c~readahead-state-based-method-protect-against-tiny-size mm/readahead.c --- a/mm/readahead.c~readahead-state-based-method-protect-against-tiny-size +++ a/mm/readahead.c @@ -1034,13 +1034,6 @@ static void limit_rala(unsigned long ra_ unsigned long stream_shift; /* - * Protect against too small I/O sizes, - * by mapping [0, 4*min] to [min, 4*min]. - */ - if (*ra_size < 4 * MIN_RA_PAGES) - *ra_size = MIN_RA_PAGES + *ra_size * 3 / 4; - - /* * Apply basic upper limits. */ if (*ra_size > ra_max) @@ -1148,6 +1141,13 @@ state_based_readahead(struct address_spa if (!adjust_rala(&ra_size, &la_size)) goto cancel_lookahead; + /* + * Protect against too small I/O sizes, + * by mapping [0, 4*min] to [min, 4*min]. + */ + if (ra_size < 4 * MIN_RA_PAGES) + ra_size = MIN_RA_PAGES + ra_size * 3 / 4; + growth_limit = req_size; growth_limit += ra_max / 16; growth_limit += 2 * ra_old; _