Fix scheduling issue where time didn't advance if a host was always ready

build_coverage.sh

@@ -9,7 +9,7 @@ echo "=== Step 1: Building simulation with coverage instrumentation ==="
 gcc src/sha256.c src/basic.c src/file_system.c src/byte_queue.c src/file_tree.c \
     src/message.c src/tcp.c src/wal.c src/hash_set.c src/client.c \
     src/metadata_server.c src/chunk_server.c src/random_client.c src/main.c \
-    quakey/src/lfs.c quakey/src/lfs_util.c quakey/src/quakey.c \
+    quakey/src/mockfs.c quakey/src/quakey.c \
     -o "$SIMULATION_BINARY" \
     -Iquakey/include -Iinclude \
     -Wall -Wextra -ggdb -O0 \

quakey/include/quakey.h

@@ -40,6 +40,10 @@ typedef enum {
 
 typedef struct {
 
+    // Label associated to the process for debugging
+    // The string must have global lifetime
+    char *name;
+
     // Size of the opaque state struct
     int state_size;
 

quakey/src/quakey.c

@@ -235,6 +235,8 @@ struct Host {
     // Pointer to the parent simulation object
     Sim *sim;
 
+    char *name;
+
     // Platform used by this host
     QuakeyPlatform platform;
 
@@ -275,6 +277,7 @@ struct Host {
     int           poll_timeout;
 
     b32 timedout;
+    b32 blocked;
 
     // Current error number set by system call mocks
     int errno_;
@@ -886,6 +889,7 @@ static int split_args(char *arg, char **argv, int max_argc)
 static void host_init(Host *host, Sim *sim, QuakeySpawn config, char *arg)
 {
     host->sim = sim;
+    host->name = config.name;
     host->platform = config.platform;
     host->next_ephemeral_port = FIRST_EPHEMERAL_PORT;
 
@@ -943,6 +947,7 @@ static void host_init(Host *host, Sim *sim, QuakeySpawn config, char *arg)
     }
 
     host->timedout = false;
+    host->blocked = false;
     host->poll_count = 0;
     host->poll_timeout = -1;
 
@@ -1019,6 +1024,9 @@ static bool is_desc_idx_valid(Host *host, int desc_idx);
 
 static bool host_ready(Host *host)
 {
+    if (host->blocked)
+        return false;
+
     if (host->timedout)
         return true;
 
@@ -2170,15 +2178,20 @@ static b32 sim_update(Sim *sim)
         if (host_idx > -1)
             break;
 
-        if (sim->num_events == 0)
+        for (int i = 0; i < sim->num_hosts; i++)
-            __builtin_trap(); // TODO: remove me
+            sim->hosts[i]->blocked = false;
 
         advance_time_to_next_event(sim);
         process_events_at_current_time(sim);
     }
 
     move_host_to_last(sim, host_idx);
-    host_update(sim->hosts[sim->num_hosts-1]);
+
+    Host *host = sim->hosts[sim->num_hosts-1];
+    host_update(host);
+    if (host_ready(host))
+        host->blocked = true;
+
     return true;
 }
 

src/client.c

@@ -36,7 +36,8 @@ typedef pthread_mutex_t Mutex;
 
 #define PARALLEL_LIMIT 5
 
-#define CLIENT_TRACE(fmt, ...) fprintf(stderr, "CLIENT: " fmt "\n", ##__VA_ARGS__);
+#define CLIENT_TRACE(fmt, ...) {}
+//#define CLIENT_TRACE(fmt, ...) fprintf(stderr, "CLIENT: " fmt "\n", ##__VA_ARGS__);
 
 typedef struct {
     SHA256   hash;

src/main.c

@@ -131,6 +131,7 @@ int main(void)
     // Client
     {
         QuakeySpawn config = {
+            .name       = "client",
             .state_size = sizeof(RandomClient),
             .init_func  = random_client_init,
             .tick_func  = random_client_tick,
@@ -146,6 +147,7 @@ int main(void)
     // Metadata Server
     {
         QuakeySpawn config = {
+            .name       = "ms",
             .state_size = sizeof(MetadataServer),
             .init_func  = metadata_server_init,
             .tick_func  = metadata_server_tick,
@@ -161,6 +163,7 @@ int main(void)
     // Chunk Server
     {
         QuakeySpawn config = {
+            .name       = "cs",
             .state_size = sizeof(ChunkServer),
             .init_func  = chunk_server_init,
             .tick_func  = chunk_server_tick,

src/metadata_server.c

@@ -9,7 +9,8 @@
 #include "message.h"
 #include "metadata_server.h"
 
-#define MS_TRACE(fmt, ...) fprintf(stderr, "MS: " fmt "\n", ##__VA_ARGS__);
+#define MS_TRACE(fmt, ...) {}
+//#define MS_TRACE(fmt, ...) fprintf(stderr, "MS: " fmt "\n", ##__VA_ARGS__);
 
 static void chunk_server_peer_init(ChunkServerPeer *chunk_server, Time current_time)
 {