qty is the maximum number of discard that _do_ fit in the timeout, not the first amount that does _not_ fit anymore. This seemingly harmless error has a very severe performance impact when the timeout value is enough for only 1 erase group. Signed-off-by: David Jander <david@xxxxxxxxxxx> --- drivers/mmc/core/core.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 92e7671..1f9573b 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -2234,16 +2234,13 @@ static unsigned int mmc_do_calc_max_discard(struct mmc_card *card, if (!qty) return 0; - if (qty == 1) - return 1; - /* Convert qty to sectors */ if (card->erase_shift) - max_discard = --qty << card->erase_shift; + max_discard = qty << card->erase_shift; else if (mmc_card_sd(card)) max_discard = qty; else - max_discard = --qty * card->erase_size; + max_discard = qty * card->erase_size; return max_discard; } -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
