[GC] Added option to collect garbage before timeout expires

src/lj_api.c

@@ -26,6 +26,63 @@
 #include "lj_strscan.h"
 #include "lj_strfmt.h"
 
+#include <time.h>
+#if LJ_TARGET_POSIX
+#include <sys/time.h>
+#elif LJ_TARGET_WINDOWS
+#define timercmp(a, b, CMP) \
+ (((a)->tv_sec == (b)->tv_sec) ? \
+ ((a)->tv_nsec CMP (b)->tv_nsec) : \
+ ((a)->tv_sec CMP (b)->tv_sec))
+#define timeradd(a, b, result) \
+ do { \
+ (result)->tv_sec = (a)->tv_sec + (b)->tv_sec; \
+ (result)->tv_nsec = (a)->tv_nsec + (b)->tv_nsec; \
+ if ((result)->tv_nsec >= 1000000000) \
+ { \
+ ++(result)->tv_sec; \
+ (result)->tv_nsec -= 1000000000; \
+ } \
+ } while (0)
+#endif
+
+static void gc_step_timeout(lua_State *L, uint32_t timeout_usec)
+{
+#if LJ_TARGET_POSIX
+ struct timeval tv_timeout;
+ tv_timeout.tv_sec = 0;
+ tv_timeout.tv_usec = timeout_usec;
+
+ struct timeval tv_current;
+ gettimeofday(&tv_current, NULL);
+
+ timeradd(&tv_current, &tv_timeout, &tv_timeout);
+ while (timercmp(&tv_current, &tv_timeout, <)) {
+ if (lj_gc_step(L) > 0) {
+ break;
+ }
+
+ gettimeofday(&tv_current, NULL);
+ }
+#elif LJ_TARGET_WINDOWS
+ struct timespec tv_timeout;
+ tv_timeout.tv_sec = 0;
+ tv_timeout.tv_nsec = timeout_usec * 1000;
+
+ struct timespec tv_current;
+ timespec_get(&tv_current, TIME_UTC);
+
+ timeradd(&tv_current, &tv_timeout, &tv_timeout);
+ while (timercmp(&tv_current, &tv_timeout, < )) {
+ if (lj_gc_step(L) > 0) {
+ break;
+ }
+
+ timespec_get(&tv_current, TIME_UTC);
+ }
+#endif
+}
+
 /* -- Common helper functions --------------------------------------------- */
 
 #define lj_checkapi_slot(idx) \
@@ -1299,11 +1356,16 @@ LUA_API int lua_gc(lua_State *L, int what, int data)
  g->gc.threshold = (a <= g->gc.total) ? (g->gc.total - a) : 0;
  while (g->gc.total >= g->gc.threshold)
  if (lj_gc_step(L) > 0) {
- res = 1;
- break;
+ res = 1;
+ break;
  }
  break;
  }
+ case LUA_GCTIMEOUT: {
+ gc_step_timeout(L, (uint32_t)data);
+ g->gc.threshold = LJ_MAX_MEM;
+ break;
+ }
  case LUA_GCSETPAUSE:
  res = (int)(g->gc.pause);
  g->gc.pause = (MSize)data;

src/lua.h

@@ -228,6 +228,7 @@ LUA_API int (lua_status) (lua_State *L);
 #define LUA_GCSETPAUSE 6
 #define LUA_GCSETSTEPMUL 7
 #define LUA_GCISRUNNING 9
+#define LUA_GCTIMEOUT 10
 
 LUA_API int (lua_gc) (lua_State *L, int what, int data);