support linear chain function calling by using list to chain modules

runtime/include/module.h

@@ -78,6 +78,7 @@ struct module {
 
 	/* Entry Function to invoke serverless function */
 	mod_main_fn_t main;
+	struct module *next_module; /* the next module in the chain */
 };
 
 /*************************

runtime/include/module_manager.h

@@ -1,9 +0,0 @@
-#pragma once
-
-#include "module.h"
-#include "ck_ht.h" 
-
-extern ck_ht_t g_module_ht;
-extern void init_module_ht();
-extern void insert_module_to_ht(const uint32_t port, const struct module* module);
-extern struct module* get_module_from_ht(const uint32_t port);

runtime/include/workflow.h

@@ -1,4 +0,0 @@
-#pragma once
-
-extern unsigned short g_single_function_flow_table[];
-extern int g_chain_length;

runtime/src/current_sandbox.c

@@ -6,9 +6,7 @@
 #include "sandbox_set_as_returned.h"
 #include "sandbox_setup_arguments.h"
 #include "scheduler.h"
-#include "workflow.h"
 #include "module.h"
-#include "module_manager.h"
 #include "software_interrupt.h"
 
 __thread struct sandbox *worker_thread_current_sandbox = NULL;
@@ -105,10 +103,11 @@ current_sandbox_start(void)
 	sandbox->completion_timestamp = __getcycles();
 
 
-	if (sandbox->current_func_index + 1 < g_chain_length) {
+	struct module * next_module = sandbox->module->next_module;
-		uint32_t next_port = g_single_function_flow_table[sandbox->current_func_index + 1];
+	//if (sandbox->current_func_index + 1 < g_chain_length) {
-		struct module * next_module = get_module_from_ht(next_port);
+	if (next_module != NULL) {
-		assert(next_module != NULL); 
+		//uint32_t next_port = g_single_function_flow_table[sandbox->current_func_index + 1];
+		//struct module * next_module = get_module_from_ht(next_port);
 		//generate a new request, copy the current sandbox's output to the next request's buffer, and put it to the global queue
 		
 		ssize_t output_length = sandbox->request_response_data_length - sandbox->request_length;

runtime/src/module.c

@@ -12,7 +12,6 @@
 #include "likely.h"
 #include "listener_thread.h"
 #include "module.h"
-#include "module_manager.h"
 #include "module_database.h"
 #include "panic.h"
 #include "runtime.h"
@@ -375,6 +374,7 @@ module_new_from_json(char *file_name)
 	int   module_count    = 0;
 	char *request_headers = NULL;
 	char *reponse_headers = NULL;
+	struct module *tail_module = NULL;
 	for (int i = 0; i < total_tokens; i++) {
 		assert(tokens[i].type == JSMN_OBJECT);
 
@@ -556,12 +556,21 @@ module_new_from_json(char *file_name)
 			                                   relative_deadline_us, port, request_size, response_size,
 			                                   admissions_percentile, expected_execution_us);
 			if (module == NULL) goto module_new_err;
-
+			
 			assert(module);
+
+			if (tail_module == NULL) {
+				tail_module = module;
+				tail_module->next_module = NULL;
+			} else {
+				tail_module->next_module = module;
+				tail_module = module;
+				tail_module->next_module = NULL;
+			}
+			
 			module_set_http_info(module, request_count, request_headers, request_content_type,
 			                     response_count, reponse_headers, response_content_type);
 			module_count++;
-			insert_module_to_ht((uint32_t)port, module);
 		}
 
 		free(request_headers);

runtime/src/module_manager.c

@@ -1,104 +0,0 @@
-#include "module_manager.h"
-
-ck_ht_t g_module_ht;
-
-static void *
-ht_malloc(size_t r)
-{
-
-        return malloc(r);
-}
-
-static void
-ht_free(void *p, size_t b, bool r)
-{
-
-        (void)b;
-        (void)r;
-        free(p);
-        return;
-}
-
-static void
-ht_hash_wrapper(struct ck_ht_hash *h,
-        const void *key,
-        size_t length,
-        uint64_t seed)
-{
-        //h->value = (unsigned long)MurmurHash64A(key, length, seed);
-        return;
-}
-
-static struct ck_malloc my_allocator = {
-        .malloc = ht_malloc,
-        .free = ht_free
-};
-
-/**
- * Module Manager Hashtable initilization Function
- * Initilize the glaoble hashtable g_module_ht
- * Returns true if initlization success, false otherwise
- */
-
-void 
-init_module_ht()
-{
-	if (ck_ht_init(&g_module_ht, CK_HT_MODE_DIRECT, NULL, &my_allocator, 2, 6602834) == false) {
-                perror("ck_ht_init");
-                exit(EXIT_FAILURE);
-        }
-
-}
-/**
- * Module Manager Insert Function
- * Insert a module with a key into a hashtable, the key is the port number.
- * The value is the module object pointer
- *
- * @param port - the TCP port number that the module will listen to
- * @param module - the module object pointer that will be inserted into the hashtable
- */
-
-void 
-insert_module_to_ht(const uint32_t port, const struct module* module) 
-{
-	assert(module != NULL);
-	ck_ht_entry_t entry;
-	ck_ht_hash_t h;
-        ck_ht_hash_direct(&h, &g_module_ht, (uintptr_t)port);	
-	ck_ht_entry_set_direct(&entry, h, (uintptr_t)port, (uintptr_t)module);
-	ck_ht_put_spmc(&g_module_ht, h, &entry);
-	printf("insert port %u, module=%p\n", port, module);
-}
-
-/**
- * Module Manager Get Function
- * Get a module from the hashtable with a key, the key is the port number.
- * Returns the module object pointer 
- *
- */
-
-struct module* 
-get_module_from_ht(const uint32_t port)
-{
-	printf("try to get module with port %u\n", port);
-	ck_ht_entry_t entry;
-        ck_ht_hash_t h;
-	ck_ht_hash_direct(&h, &g_module_ht, (uintptr_t)port);
-	ck_ht_entry_key_set_direct(&entry, (uintptr_t)port);
-	if (ck_ht_get_spmc(&g_module_ht, h, &entry) == false) { //
-                printf("ERROR: Found non-existing entry with port %u.\n", port);
-		return NULL;
-        }
-	uintptr_t k, v;
-
-        k = ck_ht_entry_key_direct(&entry);// get key from entry
-        v = ck_ht_entry_value_direct(&entry);//get value from entry
-	if (unlikely(k != port)) {
-		printf("ERROR: key doesnt match with port %u.\n", port);
-		return NULL;
-	} else {
-		printf("module found, address is =%p\n", v);
-		return (struct module*) v;	
-	}
-}
-

runtime/src/runtime.c

@@ -19,7 +19,6 @@
 #include "http_parser_settings.h"
 #include "listener_thread.h"
 #include "module.h"
-#include "module_manager.h"
 #include "runtime.h"
 #include "sandbox_request.h"
 #include "scheduler.h"
@@ -99,8 +98,6 @@ runtime_initialize(void)
 	/* Setup Scheduler */
 	scheduler_initialize(); //set function pointers to global_request_scheduler, both EDF and FIFO have a set of functions
 
-	/* Init global module hash table */
-	init_module_ht();
 	/* Configure Signals */
 	signal(SIGPIPE, SIG_IGN); // ignore SIGPIPE
 	signal(SIGTERM, runtime_cleanup); // call runtime_cleanup when get SIGTERM signal

runtime/src/workflow.c

@@ -1,6 +0,0 @@
-#include "workflow.h"
-
-unsigned short g_single_function_flow_table[] = {10000, 10001};
-int g_chain_length = 2;
-int g_execution_index = 0;
-