Merge branch '4404-add-workaround-to-force-jemalloc-linking-order-9.18' into 'bind-9.18'

[9.18] Add workaround for jemalloc linking order

See merge request isc-projects/bind9!8659

CHANGES

@@ -1,3 +1,7 @@
+6326.	[func]		Add workaround to enforce dynamic linker to pull
+			jemalloc earlier than libc to ensure all memory
+			allocations are done via jemalloc. [GL #4404]
+
 6324.	[bug]		Changes to "listen-on" statements were ignored on
 			reconfiguration unless the port or interface address was
 			changed, making it impossible to change a related

Makefile.tests

@@ -21,3 +21,8 @@ AM_CPPFLAGS +=					\
 LDADD +=						\
 	$(top_builddir)/tests/libtest/libtest.la	\
 	$(CMOCKA_LIBS)
+
+if HAVE_JEMALLOC
+AM_CFLAGS += $(JEMALLOC_CFLAGS)
+LDADD += $(JEMALLOC_LIBS)
+endif

Makefile.top

@@ -20,12 +20,20 @@ AM_LDFLAGS +=					\
 	-Wl,-flat_namespace
 endif HOST_MACOS
 
-LIBISC_CFLAGS =						\
+if HAVE_JEMALLOC
+LIBISC_CFLAGS = $(JEMALLOC_CFLAGS)
+LIBISC_LIBS = $(JEMALLOC_LIBS)
+else
+LIBISC_CFLAGS =
+LIBISC_LIBS =
+endif
+
+LIBISC_CFLAGS +=						\
 	-I$(top_srcdir)/include				\
 	-I$(top_srcdir)/lib/isc/include			\
 	-I$(top_builddir)/lib/isc/include
 
-LIBISC_LIBS = $(top_builddir)/lib/isc/libisc.la
+LIBISC_LIBS += $(top_builddir)/lib/isc/libisc.la
 
 LIBDNS_CFLAGS = \
 	-I$(top_srcdir)/lib/dns/include			\

lib/isc/include/isc/mem.h

@@ -184,7 +184,39 @@ extern unsigned int isc_mem_defaultflags;
 	} while (0)
 
 /*@{*/
+/*
+ * This is a little hack to help with dynamic link order,
+ * see https://github.com/jemalloc/jemalloc/issues/2566
+ * for more information.
+ */
+#if HAVE_JEMALLOC
+
+/*
+ * cmocka.h has confliction definitions with the jemalloc header but we only
+ * need the mallocx symbol from jemalloc.
+ */
+void *
+mallocx(size_t size, int flags);
+
+extern volatile void *isc__mem_malloc;
+
+#ifndef CMM_ACCESS_ONCE
+/*
+ * This macro has been borrowed from Userspace-RCU to ensure the access
+ * to isc__mem_malloc will not be optimized away by the compiler.
+ */
+#define CMM_ACCESS_ONCE(x) (*(__volatile__ __typeof__(x) *)&(x))
+#endif
+
+#define isc_mem_create(cp)                                            \
+	{                                                             \
+		ISCMEMFUNC(create)((cp)_ISC_MEM_FILELINE);            \
+		isc__mem_malloc = mallocx;                            \
+		ISC_INSIST(CMM_ACCESS_ONCE(isc__mem_malloc) != NULL); \
+	}
+#else
 #define isc_mem_create(cp) ISCMEMFUNC(create)((cp)_ISC_MEM_FILELINE)
+#endif
 void ISCMEMFUNC(create)(isc_mem_t **_ISC_MEM_FLARG);
 
 /*!<

lib/isc/mem.c

@@ -73,6 +73,8 @@ unsigned int isc_mem_defaultflags = ISC_MEMFLAG_DEFAULT;
 
 #define ISC_MEM_ILLEGAL_ARENA (UINT_MAX)
 
+volatile void *isc__mem_malloc = mallocx;
+
 /*
  * Constants.
  */

tests/libtest/dns.c

@@ -24,9 +24,6 @@
 #include <time.h>
 #include <unistd.h>
 
-#define UNIT_TESTING
-#include <cmocka.h>
-
 #include <isc/buffer.h>
 #include <isc/file.h>
 #include <isc/hash.h>
@@ -259,7 +256,7 @@ dns_test_tohex(const unsigned char *data, size_t len, char *buf,
 	memset(buf, 0, buflen);
 	isc_buffer_init(&target, buf, buflen);
 	result = isc_hex_totext((isc_region_t *)&source, 1, " ", &target);
-	assert_int_equal(result, ISC_R_SUCCESS);
+	INSIST(result == ISC_R_SUCCESS);
 
 	return (buf);
 }
@@ -426,7 +423,7 @@ dns_test_namefromstring(const char *namestr, dns_fixedname_t *fname) {
 
 	isc_buffer_putmem(b, (const unsigned char *)namestr, length);
 	result = dns_name_fromtext(name, b, dns_rootname, 0, NULL);
-	assert_int_equal(result, ISC_R_SUCCESS);
+	INSIST(result == ISC_R_SUCCESS);
 
 	isc_buffer_free(&b);
 }