Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 604ea906 authored by Mike Snitzer's avatar Mike Snitzer
Browse files

dm thin: adjust max_sectors_kb based on thinp blocksize



Allows for filesystems to submit bios that are a factor of the thinp
blocksize, improving dm-thinp efficiency (particularly when the data
volume is RAID).

Also set io_min to max_sectors_kb if it is a factor of the thinp
blocksize.

Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent 7d327fe0
Loading
Loading
Loading
Loading
+31 −3
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@
#include <linux/device-mapper.h>
#include <linux/dm-io.h>
#include <linux/dm-kcopyd.h>
#include <linux/log2.h>
#include <linux/list.h>
#include <linux/rculist.h>
#include <linux/init.h>
@@ -3242,14 +3243,41 @@ static void pool_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
	struct pool_c *pt = ti->private;
	struct pool *pool = pt->pool;
	uint64_t io_opt_sectors = limits->io_opt >> SECTOR_SHIFT;
	sector_t io_opt_sectors = limits->io_opt >> SECTOR_SHIFT;

	/*
	 * Adjust max_sectors_kb to highest possible power-of-2
	 * factor of pool->sectors_per_block.
	 */
	if (limits->max_hw_sectors & (limits->max_hw_sectors - 1))
		limits->max_sectors = rounddown_pow_of_two(limits->max_hw_sectors);
	else
		limits->max_sectors = limits->max_hw_sectors;

	if (limits->max_sectors < pool->sectors_per_block) {
		while (!is_factor(pool->sectors_per_block, limits->max_sectors)) {
			if ((limits->max_sectors & (limits->max_sectors - 1)) == 0)
				limits->max_sectors--;
			limits->max_sectors = rounddown_pow_of_two(limits->max_sectors);
		}
	} else if (block_size_is_power_of_two(pool)) {
		/* max_sectors_kb is >= power-of-2 thinp blocksize */
		while (!is_factor(limits->max_sectors, pool->sectors_per_block)) {
			if ((limits->max_sectors & (limits->max_sectors - 1)) == 0)
				limits->max_sectors--;
			limits->max_sectors = rounddown_pow_of_two(limits->max_sectors);
		}
	}

	/*
	 * If the system-determined stacked limits are compatible with the
	 * pool's blocksize (io_opt is a factor) do not override them.
	 */
	if (io_opt_sectors < pool->sectors_per_block ||
	    do_div(io_opt_sectors, pool->sectors_per_block)) {
	    !is_factor(io_opt_sectors, pool->sectors_per_block)) {
		if (is_factor(pool->sectors_per_block, limits->max_sectors))
			blk_limits_io_min(limits, limits->max_sectors << SECTOR_SHIFT);
		else
			blk_limits_io_min(limits, pool->sectors_per_block << SECTOR_SHIFT);
		blk_limits_io_opt(limits, pool->sectors_per_block << SECTOR_SHIFT);
	}