From patchwork Wed Dec 12 08:32:15 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: block2mtd: throttle writes by calling balance_dirty_pages_ratelimited. From: Neil Brown X-Patchwork-Id: 205455 Message-Id: <20121212193215.645da577@notabene.brown> To: Joern Engel , David Woodhouse Cc: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Date: Wed, 12 Dec 2012 19:32:15 +1100 If you create a block2mtd device that is larger than main memory, and write to all of it, then lots of pages will be dirtied but they will never be flushed out as nothing calls any variant of balance_dirty_pages. It would be nice to call set_page_dirty_balance(), but that isn't exported, so just call balance_dirty_pages_ratelimited() directly. Signed-off-by: NeilBrown diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c index 681e2ee..2c3e8e7 100644 --- a/drivers/mtd/devices/block2mtd.c +++ b/drivers/mtd/devices/block2mtd.c @@ -62,6 +62,7 @@ static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len) memset(page_address(page), 0xff, PAGE_SIZE); set_page_dirty(page); unlock_page(page); + balance_dirty_pages_ratelimited(mapping); break; } @@ -152,6 +153,7 @@ static int _block2mtd_write(struct block2mtd_dev *dev, const u_char *buf, memcpy(page_address(page) + offset, buf, cpylen); set_page_dirty(page); unlock_page(page); + balance_dirty_pages_ratelimited(mapping); } page_cache_release(page);