tsan: add memory_limit_mb flag

The flag allows to bound maximum process memory consumption (best effort).
If RSS reaches memory_limit_mb, tsan flushes all shadow memory.

llvm-svn: 191913

1 files changed, 22 insertions, 1 deletions

diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl.cc b/compiler-rt/lib/tsan/rtl/tsan_rtl.cc
index aa8934adab4..9703bb46a89 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl.cc
@@ -130,17 +130,38 @@ static void BackgroundThread(void *arg) {
   }
 
   u64 last_flush = NanoTime();
+  uptr last_rss = 0;
   for (int i = 0; ; i++) {
     SleepForSeconds(1);
     u64 now = NanoTime();
 
     // Flush memory if requested.
-    if (flags()->flush_memory_ms) {
+    if (flags()->flush_memory_ms > 0) {
       if (last_flush + flags()->flush_memory_ms * kMs2Ns < now) {
+        if (flags()->verbosity > 0)
+          Printf("ThreadSanitizer: periodic memory flush\n");
         FlushShadowMemory();
         last_flush = NanoTime();
       }
     }
+    if (flags()->memory_limit_mb > 0) {
+      uptr rss = GetRSS();
+      uptr limit = uptr(flags()->memory_limit_mb) << 20;
+      if (flags()->verbosity > 0) {
+        Printf("ThreadSanitizer: memory flush check"
+               " RSS=%llu LAST=%llu LIMIT=%llu\n",
+               (u64)rss>>20, (u64)last_rss>>20, (u64)limit>>20);
+      }
+      if (2 * rss > limit + last_rss) {
+        if (flags()->verbosity > 0)
+          Printf("ThreadSanitizer: flushing memory due to RSS\n");
+        FlushShadowMemory();
+        rss = GetRSS();
+        if (flags()->verbosity > 0)
+          Printf("ThreadSanitizer: memory flushed RSS=%llu\n", (u64)rss>>20);
+      }
+      last_rss = rss;
+    }
 
     // Write memory profile if requested.
     if (mprof_fd != kInvalidFd)