feat(syscall): Implement syscall dispatch and process lifecycle (exit/wait/sleep)

1 files changed, 107 insertions, 0 deletions

diff --git a/src/kernel/spinlock.cc b/src/kernel/spinlock.cc
new file mode 100644
index 0000000..210e0b9
--- /dev/null
+++ b/src/kernel/spinlock.cc
@@ -0,0 +1,107 @@
+#include "kernel/spinlock.h"
+#include "kernel/riscv.h"
+#include "kernel/proc.h"
+#include "drivers/uart.h"
+#include "common/types.h"
+
+#define NCPU 8
+
+namespace Spinlock
+{
+    int g_noff[NCPU];
+
+    int g_intena[NCPU];
+
+    int cpuid()
+    {
+        return r_tp();
+    }
+
+    void init(struct spinlock *lk, char* name)
+    {
+        lk->name = name;
+        lk->locked = 0;
+        lk->cpu_id = -1;
+    }
+
+    void push_off()
+    {
+        int old = intr_get();
+        intr_off();
+
+        int id = cpuid();
+        if (g_noff[id] == 0)
+        {
+            g_intena[id] = old;
+        }
+        g_noff[id] += 1;
+    }
+
+    void pop_off()
+    {
+        int id = cpuid();
+        if (intr_get())
+            Drivers::uart_puts("pop_off - interruptible\n");
+
+        if (g_noff[id] < 1)
+            Drivers::uart_puts("pop_off - count error\n");
+
+        g_noff[id] -= 1;
+
+        if (g_noff[id] == 0 && g_intena[id])
+        {
+            intr_on();
+        }
+    }
+
+    int holding(struct spinlock *lk)
+    {
+        int r;
+        push_off();
+        r = (lk->locked && lk->cpu_id == cpuid());
+        pop_off();
+        return r;
+    }
+
+    void acquire(struct spinlock *lk)
+    {
+        push_off();
+
+        if(holding(lk))
+        {
+            Drivers::uart_puts("acquire: panic - recursive lock ");
+            Drivers::uart_puts(lk->name);
+            Drivers::uart_puts("\n");
+            while (1)
+                ;
+        }
+
+        while (__sync_lock_test_and_set(&lk->locked, 1) != 0)
+        {
+            // 自旋等待
+        }
+
+        __sync_synchronize();
+
+        lk->cpu_id = cpuid();
+    }
+
+    void release(struct spinlock *lk)
+    {
+        if (!holding(lk))
+        {
+            Drivers::uart_puts("release: panic - not holding\n");
+            while (1)
+                ;
+        }
+
+        lk->cpu_id = -1;
+
+        __sync_synchronize();
+
+        __sync_lock_release(&lk->locked);
+
+        pop_off();
+    }
+
+} // namespace Spinlock