[RFC PATCH 12/16] DM: release unneeded buffer as soon as possible.

From: Ram Pai
Date: Mon Aug 15 2016 - 13:38:00 EST


Done to conserve as much free space as possible. Waiting to release till the
bio is done will unneccesarily hog up memory.

Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx>
---
drivers/md/dm-inplace-compress.c | 14 +++++++++++---
1 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/md/dm-inplace-compress.c b/drivers/md/dm-inplace-compress.c
index bc1cf70..b1c3e5f 100644
--- a/drivers/md/dm-inplace-compress.c
+++ b/drivers/md/dm-inplace-compress.c
@@ -977,7 +977,7 @@ static struct dm_icomp_io_range *dm_icomp_create_io_read_range(
io->comp_kmap = (segments == 1);
/* note down the requested length for decompress buffer.
* but dont allocate it yet.
- /
+ */
io->decomp_req_len = decomp_len;
return io;
}
@@ -1375,8 +1375,13 @@ static int dm_icomp_handle_write_modify(struct dm_icomp_io_range *io,
}

dm_icomp_get_req(req);
- if (ret == 1)
+
+ if (ret == 1) {
io->io_req.mem.ptr.addr = io->decomp_data + (offset << 9);
+ dm_icomp_release_comp_buffer(io);
+ } else
+ dm_icomp_release_decomp_buffer(io);
+
io->io_region.count = comp_len >> 9;
io->io_region.sector = start + req->info->data_start;

@@ -1443,8 +1448,11 @@ static void dm_icomp_handle_write_comp(struct dm_icomp_req *req)
io->io_region.sector = req->bio->bi_iter.bi_sector +
req->info->data_start;

- if (ret == 1)
+ if (ret == 1) {
io->io_req.mem.ptr.addr = io->decomp_data;
+ dm_icomp_release_comp_buffer(io);
+ } else
+ dm_icomp_release_decomp_buffer(io);

io->io_region.count = comp_len >> 9;
io->io_req.bi_rw = req->bio->bi_rw;
--
1.7.1