sched: allocate PUSCH only in cell grid allocator at the slot give in PUSCH grant

herlesupreeth · codebot · commit 8651df530a8b · 2024-08-30T12:16:41.000Z
diff --git a/lib/scheduler/ue_scheduling/ue_cell_grid_allocator.cpp b/lib/scheduler/ue_scheduling/ue_cell_grid_allocator.cpp
@@ -554,9 +554,11 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
     return {alloc_status::invalid_params};
   }
 
+  slot_point pusch_slot = grant.pusch_slot;
+
   // Create PUSCH param candidate search object.
   ue_pusch_alloc_param_candidate_searcher candidates{
-      u, grant.cell_index, h_ul, pdcch_alloc.slot, slots_with_no_pusch_space};
+      u, grant.cell_index, h_ul, pdcch_alloc.slot, slots_with_no_pusch_space, pusch_slot};
   if (candidates.is_empty()) {
     // The conditions for a new PUSCH allocation for this UE were not met (e.g. lack of available SearchSpaces).
     return {alloc_status::skip_ue};
@@ -582,17 +584,15 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
     // transmission starting in symbol j by a PDCCH ending in symbol i, the UE is not expected to be scheduled to
     // transmit a PUSCH starting earlier than the end of the first PUSCH by a PDCCH that ends later than symbol i".
     if (ue_cc->last_pusch_allocated_slot.valid() and pusch_alloc.slot <= ue_cc->last_pusch_allocated_slot) {
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_ue};
     }
 
     // Check if there is space in PUSCH resource grid.
     const bool is_pusch_full =
         std::find(slots_with_no_pusch_space.begin(), slots_with_no_pusch_space.end(), pusch_alloc.slot) !=
         slots_with_no_pusch_space.end();
     if (is_pusch_full) {
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_slot};
     }
 
     if (not cell_cfg.is_ul_enabled(pusch_alloc.slot)) {
@@ -602,8 +602,7 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
           u.crnti,
           pusch_alloc.slot,
           final_k2);
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_slot};
     }
 
     // When checking the number of remaining grants for PUSCH, take into account that the PUCCH grants for this UE will
@@ -625,8 +624,7 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
                     pusch_alloc.slot,
                     expert_cfg.max_puschs_per_slot);
       }
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_slot};
     }
 
     // [Implementation-defined] We skip allocation of PUSCH if there is already a PUCCH grant scheduled using common
@@ -637,8 +635,7 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
                    u.ue_index,
                    u.crnti,
                    pusch_alloc.slot);
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_ue};
     }
 
     const unsigned start_ul_symbols =
@@ -664,16 +661,14 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
                    pusch_alloc.slot,
                    start_rb,
                    end_rb);
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_slot};
     }
 
     const crb_interval ul_crb_lims = {start_rb, end_rb};
     const prb_bitmap   used_crbs   = pusch_alloc.ul_res_grid.used_crbs(scs, ul_crb_lims, pusch_td_cfg.symbols);
     if (used_crbs.all()) {
       slots_with_no_pusch_space.push_back(pusch_alloc.slot);
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_slot};
     }
 
     // Compute the MCS and the number of PRBs, depending on the pending bytes to transmit.
@@ -733,8 +728,7 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
                    u.ue_index,
                    u.crnti,
                    pusch_alloc.slot);
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_slot};
     }
 
     // In case of Retx, the #CRBs need to stay the same.
@@ -745,8 +739,7 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
           u.crnti,
           pusch_alloc.slot,
           h_ul.id);
-      // Try next candidate.
-      continue;
+      return {alloc_status::skip_ue};
     }
 
     // Verify there is no RB collision.
@@ -758,8 +751,7 @@ alloc_result ue_cell_grid_allocator::allocate_ul_grant(const ue_pusch_grant& gra
                      pusch_alloc.slot,
                      crbs.start(),
                      crbs.stop());
-      // Try next candidate.
-      continue;
+      return {alloc_status::invalid_params};
     }
 
     const aggregation_level aggr_lvl =
diff --git a/lib/scheduler/ue_scheduling/ue_pusch_alloc_param_candidate_searcher.h b/lib/scheduler/ue_scheduling/ue_pusch_alloc_param_candidate_searcher.h
@@ -157,13 +157,15 @@ class ue_pusch_alloc_param_candidate_searcher
                                           du_cell_index_t        cell_index,
                                           ul_harq_process&       ul_harq_,
                                           slot_point             pdcch_slot_,
-                                          span<const slot_point> slots_with_no_pusch_space_) :
+                                          span<const slot_point> slots_with_no_pusch_space_,
+                                          slot_point             pusch_slot_) :
     ue_ref(ue_ref_),
     ue_cc(ue_ref.find_cell(cell_index)),
     slots_with_no_pusch_space(slots_with_no_pusch_space_),
     ul_harq(ul_harq_),
     is_retx(not ul_harq.empty()),
-    pdcch_slot(pdcch_slot_)
+    pdcch_slot(pdcch_slot_),
+    pusch_slot(pusch_slot_)
   {
     // Cell is not part of UE configured cells.
     if (ue_cc == nullptr) {
@@ -233,12 +235,11 @@ class ue_pusch_alloc_param_candidate_searcher
     }
 
     // Check whether PUSCH Time Domain resource index is valid.
-    if (current.time_res >= (*current.ss_it)->pusch_time_domain_list.size()) {
+    if ((current.time_res >= (*current.ss_it)->pusch_time_domain_list.size()) or
+        (pdcch_slot + current.pusch_td_res().k2 != pusch_slot)) {
       return false;
     }
 
-    const slot_point pusch_slot = pdcch_slot + current.pusch_td_res().k2;
-
     // Check whether PUSCH slot is UL enabled.
     if (not ue_cc->cfg().cell_cfg_common.is_ul_enabled(pusch_slot)) {
       return false;
@@ -310,8 +311,10 @@ class ue_pusch_alloc_param_candidate_searcher
   // RNTI type used to generate ss_candidate_list.
   std::optional<dci_ul_rnti_config_type> preferred_rnti_type;
 
-  // PDCCH slot point used to verify if the PUSCH fits a UL slot.
+  // Slot at which UL PDCCH is scheduled if valid PUSCH allocation candidate is found.
   slot_point pdcch_slot;
+  // Slot at which PUSCH needs to be scheduled.
+  slot_point pusch_slot;
 };
 
 } // namespace srsran
diff --git a/tests/unittests/scheduler/ue_scheduling/ue_grid_allocator_test.cpp b/tests/unittests/scheduler/ue_scheduling/ue_grid_allocator_test.cpp
@@ -56,6 +56,15 @@ class ue_grid_allocator_tester : public ::testing::TestWithParam<duplex_mode>
     alloc.add_cell(to_du_cell_index(0), pdcch_alloc, uci_alloc, res_grid);
   }
 
+  slot_point get_next_ul_slot(const slot_point starting_slot) const
+  {
+    slot_point next_slot = starting_slot + cfg_builder_params.min_k2;
+    while (not cell_cfg.is_fully_ul_enabled(next_slot)) {
+      ++next_slot;
+    }
+    return next_slot;
+  }
+
   void run_slot()
   {
     ++current_slot;
@@ -232,6 +241,7 @@ TEST_P(ue_grid_allocator_tester, allocates_pusch_restricted_to_recommended_max_n
   const ue_pusch_grant grant1{.user                  = &slice_ues[u1.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = get_next_ul_slot(current_slot),
                               .recommended_nof_bytes = recommended_nof_bytes_to_schedule,
                               .max_nof_rbs           = max_nof_rbs_to_schedule};
 
@@ -255,6 +265,7 @@ TEST_P(ue_grid_allocator_tester, does_not_allocate_pusch_with_all_remaining_rbs_
   const ue_pusch_grant grant1{.user                  = &slice_ues[u1.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = get_next_ul_slot(current_slot),
                               .recommended_nof_bytes = u1.pending_ul_newtx_bytes()};
 
   const crb_interval cell_crbs = {cell_cfg.ul_cfg_common.init_ul_bwp.generic_params.crbs.start(),
@@ -307,16 +318,20 @@ TEST_P(ue_grid_allocator_tester, no_two_puschs_are_allocated_in_same_slot_for_a_
 
   const ue& u = add_ue(ue_creation_req);
 
+  slot_point pusch_slot = get_next_ul_slot(current_slot);
+
   // First PUSCH grant for the UE.
   const ue_pusch_grant grant1{.user                  = &slice_ues[u.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = pusch_slot,
                               .recommended_nof_bytes = nof_bytes_to_schedule};
 
   // Second PUSCH grant for the UE.
   const ue_pusch_grant grant2{.user                  = &slice_ues[u.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(1),
+                              .pusch_slot            = pusch_slot,
                               .recommended_nof_bytes = nof_bytes_to_schedule};
 
   ASSERT_TRUE(run_until([&]() {
@@ -338,29 +353,30 @@ TEST_P(ue_grid_allocator_tester, consecutive_puschs_for_a_ue_are_allocated_in_in
 
   const ue& u = add_ue(ue_creation_req);
 
+  slot_point pusch_slot = get_next_ul_slot(current_slot);
+
   // First PUSCH grant for the UE.
   const ue_pusch_grant grant1{.user                  = &slice_ues[u.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = pusch_slot,
                               .recommended_nof_bytes = nof_bytes_to_schedule};
 
   ASSERT_TRUE(
       run_until([&]() { return alloc.allocate_ul_grant(grant1, dummy_slice_id).status == alloc_status::success; }));
   ASSERT_TRUE(run_until([&]() { return find_ue_pusch(u.crnti, res_grid[0].result.ul) != nullptr; }));
-  slot_point last_pusch_alloc_slot = current_slot;
 
   run_slot();
 
-  // Second PUSCH grant for the UE.
+  // Second PUSCH grant for the UE trying to allocate PUSCH in a slot previous to grant1.
   const ue_pusch_grant grant2{.user                  = &slice_ues[u.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(1),
+                              .pusch_slot            = pusch_slot - 1,
                               .recommended_nof_bytes = nof_bytes_to_schedule};
 
-  ASSERT_TRUE(
+  ASSERT_FALSE(
       run_until([&]() { return alloc.allocate_ul_grant(grant2, dummy_slice_id).status == alloc_status::success; }));
-  ASSERT_TRUE(run_until([&]() { return find_ue_pusch(u.crnti, res_grid[0].result.ul) != nullptr; }));
-  ASSERT_GT(current_slot, last_pusch_alloc_slot);
 }
 
 TEST_P(ue_grid_allocator_tester, consecutive_pdschs_for_a_ue_are_allocated_in_increasing_order_of_time)
@@ -493,6 +509,7 @@ TEST_P(ue_grid_allocator_tester, successfully_allocated_pusch_even_with_large_ga
   const ue_pusch_grant grant1{.user                  = &slice_ues[u.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = get_next_ul_slot(current_slot),
                               .recommended_nof_bytes = nof_bytes_to_schedule};
 
   ASSERT_TRUE(
@@ -509,6 +526,7 @@ TEST_P(ue_grid_allocator_tester, successfully_allocated_pusch_even_with_large_ga
   const ue_pusch_grant grant2{.user                  = &slice_ues[u.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(1),
+                              .pusch_slot            = get_next_ul_slot(current_slot),
                               .recommended_nof_bytes = nof_bytes_to_schedule};
 
   ASSERT_TRUE(
@@ -588,15 +606,18 @@ TEST_P(ue_grid_allocator_remaining_rbs_alloc_tester, remaining_ul_rbs_are_alloca
 
   const unsigned recommended_nof_bytes_to_schedule = 200U;
 
-  const crb_interval   cell_crbs = {cell_cfg.ul_cfg_common.init_ul_bwp.generic_params.crbs.start(),
-                                    cell_cfg.ul_cfg_common.init_ul_bwp.generic_params.crbs.stop()};
+  const crb_interval   cell_crbs           = {cell_cfg.ul_cfg_common.init_ul_bwp.generic_params.crbs.start(),
+                                              cell_cfg.ul_cfg_common.init_ul_bwp.generic_params.crbs.stop()};
+  slot_point           pusch_to_alloc_slot = get_next_ul_slot(current_slot);
   const ue_pusch_grant grant1{.user                  = &slice_ues[u1.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = pusch_to_alloc_slot,
                               .recommended_nof_bytes = recommended_nof_bytes_to_schedule};
   const ue_pusch_grant grant2{.user                  = &slice_ues[u2.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = pusch_to_alloc_slot,
                               .recommended_nof_bytes = recommended_nof_bytes_to_schedule};
 
   ASSERT_TRUE(run_until([&]() {
@@ -700,6 +721,7 @@ TEST_P(ue_grid_allocator_expert_cfg_pxsch_nof_rbs_limits_tester,
   const ue_pusch_grant grant1{.user                  = &slice_ues[u1.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = get_next_ul_slot(current_slot),
                               .recommended_nof_bytes = recommended_nof_bytes_to_schedule,
                               .max_nof_rbs           = max_nof_rbs_to_schedule};
 
@@ -727,6 +749,7 @@ TEST_P(ue_grid_allocator_expert_cfg_pxsch_nof_rbs_limits_tester,
   const ue_pusch_grant grant1{.user                  = &slice_ues[u1.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = get_next_ul_slot(current_slot),
                               .recommended_nof_bytes = recommended_nof_bytes_to_schedule,
                               .max_nof_rbs           = max_nof_rbs_to_schedule};
 
@@ -787,7 +810,7 @@ TEST_P(ue_grid_allocator_expert_cfg_pxsch_crb_limits_tester, allocates_pdsch_wit
   ASSERT_EQ(find_ue_pdsch(u1.crnti, res_grid[0].result.dl.ue_grants)->pdsch_cfg.rbs.type1(), pdsch_vrb_limits);
 }
 
-TEST_P(ue_grid_allocator_expert_cfg_pxsch_crb_limits_tester, allocates_pdsch_within_expert_cfg_pusch_rb_limits)
+TEST_P(ue_grid_allocator_expert_cfg_pxsch_crb_limits_tester, allocates_pusch_within_expert_cfg_pusch_rb_limits)
 {
   sched_ue_creation_request_message ue_creation_req =
       test_helpers::create_default_sched_ue_creation_request(this->cfg_builder_params);
@@ -802,6 +825,7 @@ TEST_P(ue_grid_allocator_expert_cfg_pxsch_crb_limits_tester, allocates_pdsch_wit
   const ue_pusch_grant grant1{.user                  = &slice_ues[u1.ue_index],
                               .cell_index            = to_du_cell_index(0),
                               .h_id                  = to_harq_id(0),
+                              .pusch_slot            = get_next_ul_slot(current_slot),
                               .recommended_nof_bytes = recommended_nof_bytes_to_schedule,
                               .max_nof_rbs           = max_nof_rbs_to_schedule};
 
diff --git a/tests/unittests/scheduler/ue_scheduling/ue_pxsch_alloc_param_candidate_searcher_test.cpp b/tests/unittests/scheduler/ue_scheduling/ue_pxsch_alloc_param_candidate_searcher_test.cpp
@@ -44,6 +44,15 @@ class ue_pxsch_alloc_param_candidate_searcher_test : public ::testing::Test
     ue_cc = &ue_ptr->get_cell(to_ue_cell_index(0));
   }
 
+  slot_point get_next_ul_slot(slot_point start_slot)
+  {
+    slot_point next_ul_slot = start_slot + sched_cfg.ue.min_k1;
+    while (not cell_cfg.is_fully_ul_enabled(next_ul_slot)) {
+      ++next_ul_slot;
+    }
+    return next_ul_slot;
+  }
+
   void run_slot() { next_slot++; }
 
   const scheduler_expert_config        sched_cfg = config_helpers::make_default_scheduler_expert_config();
@@ -63,11 +72,12 @@ class ue_pxsch_alloc_param_candidate_searcher_test : public ::testing::Test
 
 TEST_F(ue_pxsch_alloc_param_candidate_searcher_test, only_searchspaces_in_ue_dedicated_cfg_is_considered)
 {
-  const harq_id_t                        h_id    = to_harq_id(0);
+  const harq_id_t                        h_id = to_harq_id(0);
+  const slot_point                       pdcch_slot{0, 0};
   span<const search_space_configuration> ss_list = ue_cc->cfg().cfg_dedicated().init_dl_bwp.pdcch_cfg->search_spaces;
 
   ue_pdsch_alloc_param_candidate_searcher dl_searcher(
-      *ue_ptr, to_du_cell_index(0), ue_cc->harqs.dl_harq(h_id), slot_point{0, 0}, {});
+      *ue_ptr, to_du_cell_index(0), ue_cc->harqs.dl_harq(h_id), pdcch_slot, {});
   ASSERT_TRUE(not dl_searcher.is_empty());
   for (const auto& candidate : dl_searcher) {
     bool ss_present_in_ue_ded_cfg =
@@ -77,8 +87,8 @@ TEST_F(ue_pxsch_alloc_param_candidate_searcher_test, only_searchspaces_in_ue_ded
     ASSERT_TRUE(ss_present_in_ue_ded_cfg);
   }
   ue_pusch_alloc_param_candidate_searcher ul_searcher(
-      *ue_ptr, to_du_cell_index(0), ue_cc->harqs.ul_harq(h_id), slot_point{0, 0}, {});
-  ASSERT_TRUE(not dl_searcher.is_empty());
+      *ue_ptr, to_du_cell_index(0), ue_cc->harqs.ul_harq(h_id), pdcch_slot, {}, get_next_ul_slot(pdcch_slot));
+  ASSERT_TRUE(not ul_searcher.is_empty());
   for (const auto& candidate : ul_searcher) {
     bool ss_present_in_ue_ded_cfg =
         std::find_if(ss_list.begin(), ss_list.end(), [&candidate](const search_space_configuration& ss_cfg) {
