Merge pull request #2904 from rainers/issue20497

fix Issue 20497 - thread with limited stackspace crashes depending on…
merged-on-behalf-of: Nicholas Wilson <[email protected]>

Author: dlang-bot

src/core/thread/osthread.d

@@ -752,11 +752,13 @@ class Thread
         version (Windows) {} else
         version (Posix)
         {
+            size_t stksz = adjustStackSize( m_sz );
+
             pthread_attr_t  attr;
 
             if ( pthread_attr_init( &attr ) )
                 onThreadError( "Error initializing thread attributes" );
-            if ( m_sz && pthread_attr_setstacksize( &attr, m_sz ) )
+            if ( stksz && pthread_attr_setstacksize( &attr, stksz ) )
                 onThreadError( "Error initializing thread stack size" );
         }
 
@@ -1535,19 +1537,7 @@ private:
     //
     this(size_t sz = 0) @safe pure nothrow @nogc
     {
-        if (sz)
-        {
-            version (Posix)
-            {
-                // stack size must be a multiple of PAGESIZE
-                sz += PAGESIZE - 1;
-                sz -= sz % PAGESIZE;
-                // and at least PTHREAD_STACK_MIN
-                if (PTHREAD_STACK_MIN > sz)
-                    sz = PTHREAD_STACK_MIN;
-            }
-            m_sz = sz;
-        }
+        m_sz = sz;
         m_call = Call.NO;
         m_curr = &m_main;
     }
@@ -3189,6 +3179,25 @@ private void onThreadError(string msg) nothrow @nogc
     throw error;
 }
 
+version (Posix)
+private size_t adjustStackSize(size_t sz) nothrow @nogc
+{
+    if (sz == 0)
+        return 0;
+
+    version (CRuntime_Glibc)
+    {
+        // TLS uses the top of the stack, so add its size to the requested size
+        sz += externDFunc!("rt.sections_elf_shared.sizeOfTLS",
+                           size_t function() @nogc nothrow)();
+    }
+    // stack size must be a multiple of PAGESIZE and at least PTHREAD_STACK_MIN
+    sz = ((sz + PAGESIZE - 1) & ~(PAGESIZE - 1));
+    if (PTHREAD_STACK_MIN > sz)
+        sz = PTHREAD_STACK_MIN;
+
+    return sz;
+}
 
 unittest
 {
@@ -3988,12 +3997,14 @@ ThreadID createLowLevelThread(void delegate() nothrow dg, uint stacksize = 0,
             return null;
         }
 
+        size_t stksz = adjustStackSize(stacksize);
+
         pthread_attr_t  attr;
 
         int rc;
         if ((rc = pthread_attr_init(&attr)) != 0)
             return ThreadID.init;
-        if (stacksize && (rc = pthread_attr_setstacksize(&attr, stacksize)) != 0)
+        if (stksz && (rc = pthread_attr_setstacksize(&attr, stksz)) != 0)
             return ThreadID.init;
         if ((rc = pthread_create(&tid, &attr, &thread_lowlevelEntry, context)) != 0)
             return ThreadID.init;

src/rt/sections_elf_shared.d

@@ -189,6 +189,15 @@ version (Shared)
             dg(tdso._tlsRange.ptr, tdso._tlsRange.ptr + tdso._tlsRange.length);
     }
 
+    size_t sizeOfTLS() nothrow @nogc
+    {
+        auto tdsos = initTLSRanges();
+        size_t sum;
+        foreach (ref tdso; *tdsos)
+            sum += tdso._tlsRange.length;
+        return sum;
+    }
+
     // interface for core.thread to inherit loaded libraries
     void* pinLoadedLibraries() nothrow @nogc
     {
@@ -282,6 +291,15 @@ else
         foreach (rng; *rngs)
             dg(rng.ptr, rng.ptr + rng.length);
     }
+
+    size_t sizeOfTLS() nothrow @nogc
+    {
+        auto rngs = initTLSRanges();
+        size_t sum;
+        foreach (rng; *rngs)
+            sum += rng.length;
+        return sum;
+    }
 }
 
 private:

test/thread/Makefile

@@ -1,6 +1,6 @@
 include ../common.mak
 
-TESTS:=fiber_guard_page external_threads tlsgc_sections test_import
+TESTS:=fiber_guard_page external_threads tlsgc_sections test_import tlsstack
 
 .PHONY: all clean
 all: $(addprefix $(ROOT)/,$(addsuffix .done,$(TESTS)))
@@ -26,6 +26,11 @@ $(ROOT)/test_import.done: $(ROOT)/%.done : $(ROOT)/%
 	$(QUIET)$(TIMELIMIT)$(ROOT)/$*
 	@touch $@
 
+$(ROOT)/tlsstack.done: $(ROOT)/%.done : $(ROOT)/%
+	@echo Testing $*
+	$(QUIET)$(TIMELIMIT)$(ROOT)/$*
+	@touch $@
+
 $(ROOT)/%: $(SRC)/%.d
 	$(QUIET)$(DMD) $(DFLAGS) -of$@ $<
 

test/thread/src/tlsstack.d

@@ -0,0 +1,38 @@
+module core.thread.test; // needs access to getStackTop()/getStackBottom()
+
+import core.stdc.stdio;
+import core.thread;
+
+ubyte[16384] data;
+
+void showThreadInfo() nothrow
+{
+    try
+    {
+        auto top = getStackTop();
+        auto bottom = getStackBottom();
+        printf("tlsdata:     %p\n", data.ptr);
+        printf("stack top:   %p\n", getStackTop());
+        printf("stack bottom:%p\n", getStackBottom());
+        printf("used stack:  %lld\n", cast(ulong)(bottom - top));
+    }
+    catch(Exception e)
+    {
+        assert(false, e.msg);
+    }
+}
+
+void main()
+{
+    printf("### main\n");
+    showThreadInfo();
+
+    printf("### thread\n");
+    auto th = new Thread(&showThreadInfo, 16384);
+    th.start();
+    th.join();
+
+    printf("### lowlevel thread\n");
+    auto llth = createLowLevelThread(() { showThreadInfo(); });
+    joinLowLevelThread(llth);
+}