Speedup walking the free-list (microsoft#4036)

* Speedup walking the free-list Signed-off-by: Alan Jowett <[email protected]> * Switch to higher level abstraction for prefetch Signed-off-by: Alan Jowett <[email protected]> --------- Signed-off-by: Alan Jowett <[email protected]> Co-authored-by: Alan Jowett <[email protected]>
Alan-Jowett · Nov 23, 2024 · 5f5c451 · 5f5c451
1 parent 726a856
commit 5f5c451
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Showing 2 changed files with 2 additions and 4 deletions.
diff --git a/libs/runtime/ebpf_epoch.c b/libs/runtime/ebpf_epoch.c
@@ -613,6 +613,7 @@ _ebpf_epoch_release_free_list(_Inout_ ebpf_epoch_cpu_entry_t* cpu_entry, int64_t
         header = CONTAINING_RECORD(entry, ebpf_epoch_allocation_header_t, list_entry);
         if (header->freed_epoch <= released_epoch) {
             ebpf_list_remove_entry(entry);
+            PrefetchForWrite(entry->Flink->Flink);
             switch (header->entry_type) {
             case EBPF_EPOCH_ALLOCATION_MEMORY:
                 ebpf_free(header);

diff --git a/libs/runtime/ebpf_hash_table.c b/libs/runtime/ebpf_hash_table.c
@@ -828,10 +828,7 @@ ebpf_hash_table_find(_In_ const ebpf_hash_table_t* hash_table, _In_ const uint8_
         goto Done;
     }
 
-#if defined(_M_X64)
-    // Prefetch the data on the assumption that it will be used by the caller soon.
-    _mm_prefetch((const char*)data, _MM_HINT_T0);
-#endif
+    PrefetchForWrite(data);
 
     *value = data;
     if (hash_table->notification_callback) {