ext/etc/etc.c in etc-1.2.0 vs ext/etc/etc.c in etc-1.3.0

@@ -50,36 +50,35 @@
 #ifndef _WIN32
 char *getenv();
 #endif
 char *getlogin();
 
-#define RUBY_ETC_VERSION "1.2.0"
+#define RUBY_ETC_VERSION "1.3.0"
 
 #ifdef HAVE_RB_DEPRECATE_CONSTANT
 void rb_deprecate_constant(VALUE mod, const char *name);
 #else
 # define rb_deprecate_constant(mod,name) ((void)(mod),(void)(name))
 #endif
 
 #include "constdefs.h"
 
-#ifdef HAVE_RB_EXT_RACTOR_SAFE
-#include "ruby/thread_native.h"
+#ifdef HAVE_RUBY_ATOMIC_H
+# include "ruby/atomic.h"
 #else
-/* Implement rb_native_mutex_x using an int */
-typedef int rb_nativethread_lock_t;
-static int rb_native_mutex_trylock(int *mutex) {
-    if (*mutex) {
-    	return 1;
-    }
-    *mutex = 1;
-    return 0;
+typedef int rb_atomic_t;
+# define RUBY_ATOMIC_CAS(var, oldval, newval) \
+    ((var) == (oldval) ? ((var) = (newval), (oldval)) : (var))
+# define RUBY_ATOMIC_EXCHANGE(var, newval) \
+    atomic_exchange(&var, newval)
+static inline rb_atomic_t
+atomic_exchange(volatile rb_atomic_t *var, rb_atomic_t newval)
+{
+    rb_atomic_t oldval = *var;
+    *var = newval;
+    return oldval;
 }
-static void rb_native_mutex_unlock(int *mutex) {
-    *mutex = 0;
-}
-#define rb_native_mutex_initialize rb_native_mutex_unlock
 #endif
 
 /* call-seq:
  *	getlogin	->  String
  *
@@ -256,16 +255,18 @@
     return Qnil;
 #endif
 }
 
 #ifdef HAVE_GETPWENT
-static rb_nativethread_lock_t passwd_blocking;
+static rb_atomic_t passwd_blocking;
 static VALUE
 passwd_ensure(VALUE _)
 {
     endpwent();
-    rb_native_mutex_unlock(&passwd_blocking);
+    if (RUBY_ATOMIC_EXCHANGE(passwd_blocking, 0) != 1) {
+	rb_raise(rb_eRuntimeError, "unexpected passwd_blocking");
+    }
     return Qnil;
 }
 
 static VALUE
 passwd_iterate(VALUE _)
@@ -280,11 +281,11 @@
 }
 
 static void
 each_passwd(void)
 {
-    if (rb_native_mutex_trylock(&passwd_blocking)) {
+    if (RUBY_ATOMIC_CAS(passwd_blocking, 0, 1)) {
 	rb_raise(rb_eRuntimeError, "parallel passwd iteration");
     }
     rb_ensure(passwd_iterate, 0, passwd_ensure, 0);
 }
 #endif
@@ -498,16 +499,18 @@
     return Qnil;
 #endif
 }
 
 #ifdef HAVE_GETGRENT
-static rb_nativethread_lock_t group_blocking;
+static rb_atomic_t group_blocking;
 static VALUE
 group_ensure(VALUE _)
 {
     endgrent();
-    rb_native_mutex_unlock(&group_blocking);
+    if (RUBY_ATOMIC_EXCHANGE(group_blocking, 0) != 1) {
+	rb_raise(rb_eRuntimeError, "unexpected group_blocking");
+    }
     return Qnil;
 }
 
 
 static VALUE
@@ -523,11 +526,11 @@
 }
 
 static void
 each_group(void)
 {
-    if (rb_native_mutex_trylock(&group_blocking)) {
+    if (RUBY_ATOMIC_CAS(group_blocking, 0, 1)) {
 	rb_raise(rb_eRuntimeError, "parallel group iteration");
     }
     rb_ensure(group_iterate, 0, group_ensure, 0);
 }
 #endif
@@ -952,15 +955,17 @@
 
 #if defined(HAVE_SCHED_GETAFFINITY) && defined(CPU_ALLOC)
 static int
 etc_nprocessors_affin(void)
 {
-    cpu_set_t *cpuset;
+    cpu_set_t *cpuset, cpuset_buff[1024 / sizeof(cpu_set_t)];
     size_t size;
     int ret;
     int n;
 
+    CPU_ZERO_S(sizeof(cpuset_buff), cpuset_buff);
+
     /*
      * XXX:
      * man page says CPU_ALLOC takes number of cpus. But it is not accurate
      * explanation. sched_getaffinity() returns EINVAL if cpuset bitmap is
      * smaller than kernel internal bitmap.
@@ -975,29 +980,28 @@
      * So, we use hardcode number for a workaround. Current linux kernel
      * (Linux 3.17) support 8192 cpus at maximum. Then 16384 must be enough.
      */
     for (n=64; n <= 16384; n *= 2) {
 	size = CPU_ALLOC_SIZE(n);
-	if (size >= 1024) {
+	if (size >= sizeof(cpuset_buff)) {
 	    cpuset = xcalloc(1, size);
 	    if (!cpuset)
 		return -1;
 	} else {
-	    cpuset = alloca(size);
-	    CPU_ZERO_S(size, cpuset);
+	    cpuset = cpuset_buff;
 	}
 
 	ret = sched_getaffinity(0, size, cpuset);
 	if (ret == 0) {
 	    /* On success, count number of cpus. */
 	    ret = CPU_COUNT_S(size, cpuset);
 	}
 
-	if (size >= 1024) {
+	if (size >= sizeof(cpuset_buff)) {
 	    xfree(cpuset);
 	}
-	if (ret > 0) {
+	if (ret > 0 || errno != EINVAL) {
 	    return ret;
 	}
     }
 
     return ret;
@@ -1197,14 +1201,10 @@
 #endif
     rb_define_const(rb_cStruct, "Passwd", sPasswd); /* deprecated name */
     rb_deprecate_constant(rb_cStruct, "Passwd");
     rb_extend_object(sPasswd, rb_mEnumerable);
     rb_define_singleton_method(sPasswd, "each", etc_each_passwd, 0);
-#ifdef HAVE_GETPWENT
-    rb_native_mutex_initialize(&passwd_blocking);
-#endif
 #ifdef HAVE_GETGRENT
-    rb_native_mutex_initialize(&group_blocking);
     sGroup = rb_struct_define_under(mEtc, "Group", "name",
 #ifdef HAVE_STRUCT_GROUP_GR_PASSWD
 				    "passwd",
 #endif
 				    "gid", "mem", NULL);