xthread_create takes fork flags

df8678a7 · Silas Boyd-Wickizer · f838a215 · df8678a7 · df8678a7 · df8678a7
--- a/bin/mapbench.cc
+++ b/bin/mapbench.cc
@@ -13,6 +13,7 @@
 #include "uspinlock.h"
 #include "mtrace.h"
 #include "pthread.h"
+#include "fcntl.h"
 #endif
 #include "xsys.h"
 #include <sys/mman.h>
@@ -20,6 +21,7 @@
 enum { readaccess = 1 };
 enum { verbose = 0 };
 enum { npg = 1 };
+enum { xthread_flags = FORK_SEPARATE_PGMAP };

 static pthread_barrier_t bar;
 static pthread_barrier_t bar2;
@@ -79,7 +81,7 @@ main(int ac, char **av)
  pthread_barrier_init(&bar2, 0, nthread);

  for(u64 i = 0; i < nthread; i++) {
-    pthread_create(&tid[i], 0, thr, (void*) i);
+    xthread_create(&tid[i], xthread_flags, thr, (void*) i);
    if (0) printf("mapbench[%d]: child %d\n", getpid(), tid);
  }


--- a/include/pthread.h
+++ b/include/pthread.h
@@ -24,3 +24,7 @@ int       pthread_barrier_init(pthread_barrier_t *b,
                               const pthread_barrierattr_t *attr,
                               unsigned count);
 int       pthread_barrier_wait(pthread_barrier_t *b);
+
+// Special xv6 pthread_create, flags is FORK_* bits
+int       xthread_create(pthread_t* tid, int flags,
+                         void* (*start)(void*), void* arg);
--- a/include/xsys.h
+++ b/include/xsys.h
 #if defined(LINUX)

 #define O_CREATE O_CREAT
+#define FORK_SEPARATE_PGMAP 0
 #define xfork() fork()
 #define xexit() exit(EXIT_SUCCESS)
 static inline void xwait()
@@ -17,6 +18,8 @@ static inline void xwait()
 #define mtenable_type(x, y) do { } while (0)
 #define mtdisable(x) do { } while(0)
 #define xpthread_join(tid) pthread_join(tid, nullptr);
+#define xthread_create(ptr, x, fn, arg) \
+  pthread_create((ptr), 0, (fn), (arg))

 #else // Must be xv6


--- a/lib/threads.cc
+++ b/lib/threads.cc
@@ -31,6 +31,20 @@ pthread_create(pthread_t* tid, const pthread_attr_t* attr,
  return 0;
 }

+int
+xthread_create(pthread_t* tid, int flags,
+               void* (*start)(void*), void* arg)
+{
+  char* base = (char*) sbrk(stack_size);
+  int t = forkt(base + stack_size, (void*) start, arg,
+                FORK_SHARE_VMAP | FORK_SHARE_FD | flags);
+  if (t < 0)
+    return t;
+
+  *tid = t;
+  return 0;
+}
+
 pthread_t
 pthread_self()
 {