fix: completion queue alignment

runtime/include/local_completion_queue.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "ps_list.h"
 #include "sandbox_types.h"
 
 void local_completion_queue_add(struct sandbox *sandbox);

runtime/include/module.h

@@ -26,7 +26,7 @@ INIT_POOL(wasm_stack, wasm_stack_free)
 struct module_pool {
 	struct wasm_memory_pool memory;
 	struct wasm_stack_pool  stack;
-} __attribute__((aligned(CACHE_PAD)));
+} CACHE_PAD_ALIGNED;
 
 struct module {
 	char    *path;
@@ -39,7 +39,7 @@ struct module {
 	struct sledge_abi__wasm_table *indirect_table;
 
 	struct module_pool *pools;
-} __attribute__((aligned(CACHE_PAD)));
+} CACHE_PAD_ALIGNED;
 
 /********************************
  * Public Methods from module.c *

runtime/include/sandbox_set_as_allocated.h

@@ -6,7 +6,6 @@
 
 #include "arch/context.h"
 #include "current_sandbox.h"
-#include "ps_list.h"
 #include "sandbox_state_history.h"
 #include "sandbox_state_transition.h"
 #include "sandbox_types.h"

runtime/include/sandbox_set_as_initialized.h

@@ -6,7 +6,6 @@
 
 #include "arch/context.h"
 #include "current_sandbox.h"
-#include "ps_list.h"
 #include "sandbox_state_history.h"
 #include "sandbox_state_transition.h"
 #include "sandbox_types.h"

runtime/include/sandbox_types.h

@@ -32,11 +32,14 @@ struct sandbox_timestamps {
 };
 
 struct sandbox {
+	/* used by ps_list's default name-based MACROS for the scheduling runqueue */
+	/* Keep as first member of sandbox struct to ensure ps_list maintains alignment */
+	struct ps_list list;
+
 	uint64_t                     id;
 	sandbox_state_t              state;
 	struct sandbox_state_history state_history;
 
-	struct ps_list list; /* used by ps_list's default name-based MACROS for the scheduling runqueue */
 
 	/* Accounting Info */
 	struct route  *route;

runtime/include/types.h

@@ -21,11 +21,13 @@
 #define round_to_cache_pad(x)    round_to_pow2((unsigned long)(x), CACHE_PAD)
 #define round_up_to_cache_pad(x) round_up_to_pow2((unsigned long)(x), CACHE_PAD)
 
-#define EXPORT       __attribute__((visibility("default")))
-#define IMPORT       __attribute__((visibility("default")))
-#define INLINE       __attribute__((always_inline))
-#define PAGE_ALIGNED __attribute__((aligned(PAGE_SIZE)))
-#define WEAK         __attribute__((weak))
+#define PAGE_ALIGNED      __attribute__((aligned(PAGE_SIZE)))
+#define CACHE_PAD_ALIGNED __attribute__((aligned(CACHE_PAD)))
+
+#define EXPORT            __attribute__((visibility("default")))
+#define IMPORT            __attribute__((visibility("default")))
+#define INLINE            __attribute__((always_inline))
+#define WEAK              __attribute__((weak))
 
 
 #ifndef unlikely

runtime/include/wasm_memory.h

@@ -56,7 +56,12 @@ static INLINE void    wasm_memory_set_f64(struct wasm_memory *wasm_memory, uint3
 static INLINE struct wasm_memory *
 wasm_memory_alloc(uint64_t initial, uint64_t max)
 {
-	struct wasm_memory *wasm_memory = aligned_alloc(4096, round_up_to_page(sizeof(struct wasm_memory)));
+	size_t alignment     = (size_t)PAGE_SIZE;
+	size_t size_to_alloc = (size_t)round_up_to_page(sizeof(struct wasm_memory));
+
+	assert(size_to_alloc % alignment == 0);
+
+	struct wasm_memory *wasm_memory = aligned_alloc(alignment, size_to_alloc);
 	if (wasm_memory == NULL) return wasm_memory;
 
 	int rc = wasm_memory_init(wasm_memory, initial, max);

runtime/include/wasm_stack.h

@@ -5,6 +5,7 @@
 #include <sys/mman.h>
 #include <string.h>
 
+#include "ps_list.h"
 #include "types.h"
 
 /**

runtime/src/local_completion_queue.c

@@ -3,7 +3,8 @@
 #include "local_completion_queue.h"
 #include "sandbox_functions.h"
 
-thread_local static struct ps_list_head local_completion_queue __attribute__((aligned(16)));
+/* Must be the same alignment as sandbox structs because of how the ps_list macros work */
+thread_local static struct ps_list_head local_completion_queue PAGE_ALIGNED;
 
 
 void
@@ -39,8 +40,6 @@ local_completion_queue_add(struct sandbox *sandbox)
 void
 local_completion_queue_free()
 {
-	if (local_completion_queue_is_empty()) return;
-
 	struct sandbox *sandbox_iterator = NULL;
 	struct sandbox *buffer           = NULL;
 

runtime/src/module.c

@@ -111,6 +111,8 @@ module_alloc(char *path)
 	size_t alignment     = (size_t)CACHE_PAD;
 	size_t size_to_alloc = (size_t)round_to_cache_pad(sizeof(struct module));
 
+	assert(size_to_alloc % alignment == 0);
+
 	struct module *module = aligned_alloc(alignment, size_to_alloc);
 	if (!module) {
 		fprintf(stderr, "Failed to allocate module: %s\n", strerror(errno));

runtime/src/sandbox.c

@@ -180,11 +180,16 @@ struct sandbox *
 sandbox_alloc(struct module *module, struct http_session *session, struct route *route, struct tenant *tenant,
               uint64_t admissions_estimate)
 {
-	struct sandbox *sandbox                   = NULL;
-	size_t          page_aligned_sandbox_size = round_up_to_page(sizeof(struct sandbox));
-	sandbox                                   = aligned_alloc(PAGE_SIZE, page_aligned_sandbox_size);
-	memset(sandbox, 0, page_aligned_sandbox_size);
+	size_t alignment     = (size_t)PAGE_SIZE;
+	size_t size_to_alloc = (size_t)round_up_to_page(sizeof(struct module));
+
+	assert(size_to_alloc % alignment == 0);
+
+	struct sandbox *sandbox = NULL;
+	sandbox                 = aligned_alloc(alignment, size_to_alloc);
+
 	if (unlikely(sandbox == NULL)) return NULL;
+	memset(sandbox, 0, size_to_alloc);
 
 	sandbox_set_as_allocated(sandbox);
 	sandbox_init(sandbox, module, session, route, tenant, admissions_estimate);