1 files changed, 22 insertions, 27 deletions

diff --git a/block.c b/block.c
index 0ae2e93..602d8a4 100644
--- a/block.c
+++ b/block.c
@@ -140,8 +140,6 @@ void bdrv_io_limits_disable(BlockDriverState *bs)
 
     bs->slice_start = 0;
     bs->slice_end   = 0;
-    bs->slice_time  = 0;
-    memset(&bs->io_base, 0, sizeof(bs->io_base));
 }
 
 static void bdrv_block_timer(void *opaque)
@@ -1433,11 +1431,10 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
     bs_dest->enable_write_cache = bs_src->enable_write_cache;
 
     /* i/o timing parameters */
-    bs_dest->slice_time         = bs_src->slice_time;
     bs_dest->slice_start        = bs_src->slice_start;
     bs_dest->slice_end          = bs_src->slice_end;
+    bs_dest->slice_submitted    = bs_src->slice_submitted;
     bs_dest->io_limits          = bs_src->io_limits;
-    bs_dest->io_base            = bs_src->io_base;
     bs_dest->throttled_reqs     = bs_src->throttled_reqs;
     bs_dest->block_timer        = bs_src->block_timer;
     bs_dest->io_limits_enabled  = bs_src->io_limits_enabled;
@@ -3750,6 +3747,7 @@ static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors,
                  bool is_write, double elapsed_time, uint64_t *wait)
 {
     uint64_t bps_limit = 0;
+    uint64_t extension;
     double   bytes_limit, bytes_base, bytes_res;
     double   slice_time, wait_time;
 
@@ -3768,9 +3766,9 @@ static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors,
     slice_time = bs->slice_end - bs->slice_start;
     slice_time /= (NANOSECONDS_PER_SECOND);
     bytes_limit = bps_limit * slice_time;
-    bytes_base  = bs->nr_bytes[is_write] - bs->io_base.bytes[is_write];
+    bytes_base  = bs->slice_submitted.bytes[is_write];
     if (bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]) {
-        bytes_base += bs->nr_bytes[!is_write] - bs->io_base.bytes[!is_write];
+        bytes_base += bs->slice_submitted.bytes[!is_write];
     }
 
     /* bytes_base: the bytes of data which have been read/written; and
@@ -3797,10 +3795,12 @@ static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors,
      * info can be kept until the timer fire, so it is increased and tuned
      * based on the result of experiment.
      */
-    bs->slice_time = wait_time * BLOCK_IO_SLICE_TIME * 10;
-    bs->slice_end += bs->slice_time - 3 * BLOCK_IO_SLICE_TIME;
+    extension = wait_time * NANOSECONDS_PER_SECOND;
+    extension = DIV_ROUND_UP(extension, BLOCK_IO_SLICE_TIME) *
+                BLOCK_IO_SLICE_TIME;
+    bs->slice_end += extension;
     if (wait) {
-        *wait = wait_time * BLOCK_IO_SLICE_TIME * 10;
+        *wait = wait_time * NANOSECONDS_PER_SECOND;
     }
 
     return true;
@@ -3828,9 +3828,9 @@ static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write,
     slice_time = bs->slice_end - bs->slice_start;
     slice_time /= (NANOSECONDS_PER_SECOND);
     ios_limit  = iops_limit * slice_time;
-    ios_base   = bs->nr_ops[is_write] - bs->io_base.ios[is_write];
+    ios_base   = bs->slice_submitted.ios[is_write];
     if (bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]) {
-        ios_base += bs->nr_ops[!is_write] - bs->io_base.ios[!is_write];
+        ios_base += bs->slice_submitted.ios[!is_write];
     }
 
     if (ios_base + 1 <= ios_limit) {
@@ -3841,7 +3841,7 @@ static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write,
         return false;
     }
 
-    /* Calc approx time to dispatch */
+    /* Calc approx time to dispatch, in seconds */
     wait_time = (ios_base + 1) / iops_limit;
     if (wait_time > elapsed_time) {
         wait_time = wait_time - elapsed_time;
@@ -3849,10 +3849,10 @@ static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write,
         wait_time = 0;
     }
 
-    bs->slice_time = wait_time * BLOCK_IO_SLICE_TIME * 10;
-    bs->slice_end += bs->slice_time - 3 * BLOCK_IO_SLICE_TIME;
+    /* Exceeded current slice, extend it by another slice time */
+    bs->slice_end += BLOCK_IO_SLICE_TIME;
     if (wait) {
-        *wait = wait_time * BLOCK_IO_SLICE_TIME * 10;
+        *wait = wait_time * NANOSECONDS_PER_SECOND;
     }
 
     return true;
@@ -3867,19 +3867,10 @@ static bool bdrv_exceed_io_limits(BlockDriverState *bs, int nb_sectors,
     int      bps_ret, iops_ret;
 
     now = qemu_get_clock_ns(vm_clock);
-    if ((bs->slice_start < now)
-        && (bs->slice_end > now)) {
-        bs->slice_end = now + bs->slice_time;
-    } else {
-        bs->slice_time  =  5 * BLOCK_IO_SLICE_TIME;
+    if (now > bs->slice_end) {
         bs->slice_start = now;
-        bs->slice_end   = now + bs->slice_time;
-
-        bs->io_base.bytes[is_write]  = bs->nr_bytes[is_write];
-        bs->io_base.bytes[!is_write] = bs->nr_bytes[!is_write];
-
-        bs->io_base.ios[is_write]    = bs->nr_ops[is_write];
-        bs->io_base.ios[!is_write]   = bs->nr_ops[!is_write];
+        bs->slice_end   = now + BLOCK_IO_SLICE_TIME;
+        memset(&bs->slice_submitted, 0, sizeof(bs->slice_submitted));
     }
 
     elapsed_time  = now - bs->slice_start;
@@ -3907,6 +3898,10 @@ static bool bdrv_exceed_io_limits(BlockDriverState *bs, int nb_sectors,
         *wait = 0;
     }
 
+    bs->slice_submitted.bytes[is_write] += (int64_t)nb_sectors *
+                                           BDRV_SECTOR_SIZE;
+    bs->slice_submitted.ios[is_write]++;
+
     return false;
 }