fix gettid==getpid for 1 thread

core/process.c

@@ -11,6 +11,7 @@ struct process {
     char name[PROCESS_NAME_MAX_LENGTH];
     int ref;
     int pid;
+    int nextTid;
     struct uAddrSpace *addrSpace;
     struct thread *thList;
 
@@ -47,7 +48,8 @@ struct process *processCreate(char *name)
     new->ref = 1;
 
     disable_IRQs(flags);
-    new->pid = nextPid++;
+    new->pid     = nextPid++;
+    new->nextTid = new->pid;
     list_add_tail(processList, new);
     restore_IRQs(flags);
 
@@ -180,3 +182,11 @@ struct uAddrSpace *processGetAddrSpace(struct process *proc){
 int processInitHeap(struct process *proc, uaddr_t lastUserAddr){
     return uAddrSpaceSetHeap(proc->addrSpace, lastUserAddr, 0);
 }
+
+int processGetId(struct process *proc){
+    return proc->pid;
+}
+
+int processGetNextTid(struct process *proc){
+    return proc->nextTid++;
+}

core/process.h

@@ -18,3 +18,5 @@ int processRemoveThread(struct thread *th);
 struct mmu_context *processGetMMUContext(struct process *th);
 struct uAddrSpace *processGetAddrSpace(struct process *proc);
 int processInitHeap(struct process *proc, uaddr_t lastUserAddr);
+int processGetId(struct process *proc);
+int processGetNextTid(struct process *proc);

core/syscall.c

@@ -113,11 +113,14 @@ int syscallExecute(int syscallId, const struct cpu_state *userCtx)
         }
         case SYSCALL_ID_NEW_THREAD: {
             struct uAddrSpace *as;
+            thread_id_t threadIdPtr;
+            thread_id_t threadId;
             uaddr_t funcAddr;
             uint32_t arg1, arg2;
             size_t stackSize;
 
-            ret = syscallGet4args(userCtx, (unsigned int *)&funcAddr, (unsigned int *)&arg1,
+            ret = syscallGet5args(userCtx, (unsigned int *)&threadIdPtr,
+                                  (unsigned int *)&funcAddr, (unsigned int *)&arg1,
                                   (unsigned int *)&arg2, (unsigned int *)&stackSize);
             if (ret)
                 break;
@@ -125,6 +128,11 @@ int syscallExecute(int syscallId, const struct cpu_state *userCtx)
                 ret = -EINVAL;
                 break;
             }
+            if (memcpyFromUser((vaddr_t)&threadId, threadIdPtr, sizeof(threadId)) !=
+                sizeof(threadId)) {
+                ret = -EFAULT;
+                break;
+            }
 
             as        = processGetAddrSpace(getCurrentThread()->process);
             stackSize = ALIGN(stackSize, PAGE_SIZE);
@@ -142,6 +150,13 @@ int syscallExecute(int syscallId, const struct cpu_state *userCtx)
                 ret = -ENOMEM;
                 uAddrSpaceUnmap(as, stackAddr, stackSize);
             }
+            threadId = threadGetId(th);
+
+            if (memcpyToUser(threadIdPtr, (vaddr_t)&threadId, sizeof(threadId)) !=
+                sizeof(threadId)) {
+                ret = -EFAULT;
+                break;
+            }
 
             break;
         }
@@ -156,6 +171,14 @@ int syscallExecute(int syscallId, const struct cpu_state *userCtx)
 
             break;
         }
+        case SYSCALL_ID_GETPID: {
+            ret        = processGetId(getCurrentThread()->process);
+            break;
+        }
+        case SYSCALL_ID_GETTID: {
+            ret        = threadGetId(getCurrentThread());
+            break;
+        }
         default:
             printf("Unknon syscall id %d\n", syscallId);
             ret = -ENOENT;

core/syscall.h

@@ -13,6 +13,8 @@
 #define SYSCALL_ID_MUNMAP 8
 #define SYSCALL_ID_NEW_THREAD 9
 #define SYSCALL_ID_USLEEP 10
+#define SYSCALL_ID_GETPID 11
+#define SYSCALL_ID_GETTID 12
 
 #ifdef __KERNEL__
 int syscallExecute(int syscallId, const struct cpu_state *user_ctx);

core/thread.c

@@ -12,6 +12,12 @@
 
 static struct thread *currentThread;
 static struct thread *threadWithTimeout;
+static thread_id_t nextTid; // This is the TID for kernel thread ONLY
+
+thread_id_t threadGetId(struct thread *th)
+{
+    return th->tid;
+}
 
 static void threadPrepareContext(struct thread *th);
 
@@ -84,6 +90,7 @@ struct thread *threadCreate(const char *name, cpu_kstate_function_arg1_t func, v
         goto free_mem;
 
     thread->state = READY;
+    thread->tid = nextTid++;
     uint32_t flags;
     disable_IRQs(flags);
     list_add_tail(currentThread, thread);
@@ -124,6 +131,7 @@ struct thread *threadCreateUser(const char *name, struct process *proc, uaddr_t
         goto free_mem;
 
     thread->state = READY;
+    thread->tid = processGetNextTid(proc);
     uint32_t flags;
     disable_IRQs(flags);
     list_add_tail(currentThread, thread);

core/thread.h

@@ -17,8 +17,11 @@ typedef enum {
     EXITING
 } thread_state;
 
+typedef unsigned long int thread_id_t;
+
 struct thread {
     char name[THREAD_NAME_MAX_LENGTH];
+    thread_id_t tid;
     struct cpu_state *cpuState;
     thread_state state;
     vaddr_t stackAddr;
@@ -89,3 +92,4 @@ struct thread *getCurrentThread();
 int threadAddThread(struct thread *th);
 int threadChangeCurrentContext(struct mmu_context *ctx);
 int threadCount();
+thread_id_t threadGetId(struct thread *th);

userspace/kernel/syscall.h

@@ -13,6 +13,8 @@
 #define SYSCALL_ID_MUNMAP 8
 #define SYSCALL_ID_NEW_THREAD 9
 #define SYSCALL_ID_USLEEP 10
+#define SYSCALL_ID_GETPID 11
+#define SYSCALL_ID_GETTID 12
 
 #ifdef __KERNEL__
 int syscallExecute(int syscallId, const struct cpu_state *user_ctx);

userspace/libc.c

@@ -5,6 +5,7 @@
 #include "swintr.h"
 #include "sys/mman.h"
 #include "syscall.h"
+#include "thread.h"
 #include "unistd.h"
 
 int errno = 0;
@@ -761,12 +762,19 @@ static void thread_runner()
     _exit(0);
 }
 
-int new_thread(start_routine *func, void *arg, size_t stackSize)
-{
-    return syscall4(SYSCALL_ID_NEW_THREAD, (unsigned int)thread_runner, (unsigned int)func,
+int thread_create(pthread_t *thread, start_routine *func, void *arg, size_t stackSize) {
+    return syscall5(SYSCALL_ID_NEW_THREAD, (unsigned int)thread, (unsigned int)thread_runner, (unsigned int)func,
                     (unsigned int)arg, stackSize);
 }
 
 int usleep(useconds_t usec) {
     return syscall1(SYSCALL_ID_USLEEP, (unsigned int)usec);
 }
+
+pid_t gettid(void) {
+    return syscall0(SYSCALL_ID_GETTID);
+}
+
+pid_t getpid(void) {
+    return syscall0(SYSCALL_ID_GETPID);
+}

userspace/libc.h

@@ -4,6 +4,7 @@
 #include "stdint.h"
 #include "stddef.h"
 #include "minmax.h"
+#include "unistd.h"
 
 #define islower(c) (('a' <= (c)) && ((c) <= 'z'))
 #define isupper(c) (('A' <= (c)) && ((c) <= 'Z'))
@@ -63,6 +64,6 @@ void *malloc(size_t size);
 void *calloc(size_t nmemb, size_t size);
 void *realloc(void *ptr, size_t size);
 void free(void *ptr);
+pid_t gettid(void);
+pid_t getpid(void);
 
-typedef void *(start_routine)(void *);
-int new_thread(start_routine *func, void *arg, size_t stackSize);

userspace/main_user.c

@@ -3,6 +3,7 @@
 #include "stdarg.h"
 #include "stddef.h"
 #include "sys/mman.h"
+#include "thread.h"
 #include "tiny.h"
 #include "unistd.h"
 
@@ -122,14 +123,15 @@ int func_munmap()
 
 static void *print_hello(void *arg) {
         (void)arg;
-        printf("Hello World from thread\n");
+        printf("Hello World from thread %d\n", gettid());
         usleep(100);
 
         return NULL;
 }
 
 int func_thread() {
-        new_thread(print_hello, NULL, 4096);
+        pthread_t id;
+        thread_create(&id, print_hello, NULL, 4096);
 
         return 0;
 }
@@ -138,6 +140,7 @@ int main(int argc, char *argv[]) {
         (void)argc;
         (void)argv;
         char buf[64];
+        assert(getpid() == gettid());
         printf("Shell starting... type \"help\" for help\n");
         while (1) {
                 printf(">");

userspace/thread.h

@@ -0,0 +1,6 @@
+#pragma once
+#include <stddef.h>
+
+typedef unsigned long int pthread_t;
+typedef void *(start_routine)(void *);
+int thread_create(pthread_t *thread, start_routine *func, void *arg, size_t stackSize);

userspace/unistd.h

@@ -2,3 +2,5 @@
 
 typedef unsigned int useconds_t;
 int usleep(useconds_t usec);
+
+typedef int pid_t;