summaryrefslogtreecommitdiffstats
path: root/drivers/target
diff options
context:
space:
mode:
authorMike Christie <mchristi@redhat.com>2017-11-28 12:40:38 -0600
committerNicholas Bellinger <nab@linux-iscsi.org>2018-01-12 15:07:18 -0800
commitf890f5799a6628fe006ae524e625900186074cdb (patch)
tree92037aa47ad752385e0b66328e5911bbf3fb4ad0 /drivers/target
parent6fd0ce79724dabe2cd0bd8aed111cbe94755bf88 (diff)
downloadlinux-f890f5799a6628fe006ae524e625900186074cdb.tar.bz2
tcmu: simplify dbi thresh handling
We do not really save a lot by trying to increase thresh a multiple of the existing value. This just simplifies the code by increasing it to whatever is needed for the command being executed. Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target')
-rw-r--r--drivers/target/target_core_user.c22
1 files changed, 3 insertions, 19 deletions
diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index 68d1d7214eeb..2679e4dcd0f1 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -79,7 +79,6 @@
#define DATA_BLOCK_SIZE PAGE_SIZE
#define DATA_BLOCK_BITS (256 * 1024)
#define DATA_SIZE (DATA_BLOCK_BITS * DATA_BLOCK_SIZE)
-#define DATA_BLOCK_INIT_BITS 128
/* The total size of the ring is 8M + 256K * PAGE_SIZE */
#define TCMU_RING_SIZE (CMDR_SIZE + DATA_SIZE)
@@ -700,7 +699,6 @@ static bool is_ring_space_avail(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
if ((space * DATA_BLOCK_SIZE) < data_needed) {
unsigned long blocks_left = DATA_BLOCK_BITS - udev->dbi_thresh +
space;
- unsigned long grow;
if (blocks_left < blocks_needed) {
pr_debug("no data space: only %lu available, but ask for %zu\n",
@@ -709,23 +707,9 @@ static bool is_ring_space_avail(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
return false;
}
- /* Try to expand the thresh */
- if (!udev->dbi_thresh) {
- /* From idle state */
- uint32_t init_thresh = DATA_BLOCK_INIT_BITS;
-
- udev->dbi_thresh = max(blocks_needed, init_thresh);
- } else {
- /*
- * Grow the data area by max(blocks needed,
- * dbi_thresh / 2), but limited to the max
- * DATA_BLOCK_BITS size.
- */
- grow = max(blocks_needed, udev->dbi_thresh / 2);
- udev->dbi_thresh += grow;
- if (udev->dbi_thresh > DATA_BLOCK_BITS)
- udev->dbi_thresh = DATA_BLOCK_BITS;
- }
+ udev->dbi_thresh += blocks_needed;
+ if (udev->dbi_thresh > DATA_BLOCK_BITS)
+ udev->dbi_thresh = DATA_BLOCK_BITS;
}
return tcmu_get_empty_blocks(udev, cmd);