From f36057d7edbe4e43f1768aed8aae719264667bc8 Mon Sep 17 00:00:00 2001
From: Simon Bjurek <simbj106@student.liu.se>
Date: Thu, 30 Jan 2025 11:00:26 +0100
Subject: [PATCH] there is a bug that can occur when an op is scheduled before
predecessors
---
b_asic/scheduler.py | 34 +++++++++++++++++++++++++---------
1 file changed, 25 insertions(+), 9 deletions(-)
diff --git a/b_asic/scheduler.py b/b_asic/scheduler.py
index a7d1b85a..b17b4842 100644
--- a/b_asic/scheduler.py
+++ b/b_asic/scheduler.py
@@ -181,7 +181,7 @@ class EarliestDeadlineScheduler(Scheduler):
Schedule to apply the scheduling algorithm on.
"""
- # TODO: Take the execution time into consideration!
+ # TODO: Solve bug where operation (ADD) is scheduled before proceeding (MUL) -> pipelining
ALAPScheduler().apply_scheduling(schedule)
@@ -190,9 +190,15 @@ class EarliestDeadlineScheduler(Scheduler):
input_op = cast(Input, input_op)
schedule.move_operation_asap(input_op.graph_id)
+ # construct the set of remaining operations, excluding inputs
remaining_ops = set(schedule.start_times.keys())
remaining_ops = {elem for elem in remaining_ops if not elem.startswith("in")}
+ # construct a dictionarry for storing how many times until a resource is available again
+ used_resources_ready_times = {}
+
+ # iterate through all remaining operations and schedule them
+ # while not exceeding the available resources
remaining_resources = self._max_resources.copy()
current_time = 0
while remaining_ops:
@@ -202,13 +208,23 @@ class EarliestDeadlineScheduler(Scheduler):
if not best_candidate:
current_time += 1
- remaining_resources = self._max_resources.copy()
+
+ # update available operators
+ for operation, ready_time in used_resources_ready_times.items():
+ print(ready_time, current_time)
+ if ready_time == current_time:
+ remaining_resources[operation.type_name()] += 1
+ # remaining_resources = self._max_resources.copy()
continue
- # update remaining resources
+ # if the resource is constrained, update remaining resources
if best_candidate.type_name() in remaining_resources:
remaining_resources[best_candidate.type_name()] -= 1
+ used_resources_ready_times[best_candidate] = (
+ current_time + best_candidate.execution_time
+ )
+ # schedule the best candidate to the current time
remaining_ops.remove(best_candidate.graph_id)
schedule.start_times[best_candidate.graph_id] = current_time
@@ -222,11 +238,16 @@ class EarliestDeadlineScheduler(Scheduler):
def _find_best_candidate(
schedule, remaining_ops, remaining_resources, current_time
):
- # precompute source end times for faster checks
sfg = schedule.sfg
source_end_times = defaultdict(float)
+
+ # find the best candidate
+ best_candidate = None
+ best_deadline = float('inf')
for op_id in remaining_ops:
operation = sfg.find_by_id(op_id)
+
+ # compute maximum end times of preceding operations
for op_input in operation.inputs:
source_op = op_input.signals[0].source.operation
if not isinstance(source_op, Delay):
@@ -235,11 +256,6 @@ class EarliestDeadlineScheduler(Scheduler):
schedule.start_times[source_op.graph_id] + source_op.latency,
)
- best_candidate = None
- best_deadline = float('inf')
- for op_id in remaining_ops:
- operation = sfg.find_by_id(op_id)
-
# check resource constraints
if operation.type_name() in remaining_resources:
if remaining_resources[operation.type_name()] == 0:
--
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