Fix "prof.reset" mallctl-related corruption.

Fix heap profiling to distinguish among otherwise identical sample sites
with interposed resets (triggered via the "prof.reset" mallctl).  This
bug could cause data structure corruption that would most likely result
in a segfault.

1 files changed, 66 insertions, 15 deletions

diff --git a/test/unit/prof_reset.c b/test/unit/prof_reset.c
index da34d70..69983e5 100644
--- a/test/unit/prof_reset.c
+++ b/test/unit/prof_reset.c
@@ -16,6 +16,14 @@ prof_dump_open_intercept(bool propagate_err, const char *filename)
 	return (fd);
 }
 
+static void
+set_prof_active(bool active)
+{
+
+	assert_d_eq(mallctl("prof.active", NULL, NULL, &active, sizeof(active)),
+	    0, "Unexpected mallctl failure");
+}
+
 static size_t
 get_lg_prof_sample(void)
 {
@@ -97,15 +105,12 @@ prof_dump_header_intercept(bool propagate_err, const prof_cnt_t *cnt_all)
 
 TEST_BEGIN(test_prof_reset_cleanup)
 {
-	bool active;
 	void *p;
 	prof_dump_header_t *prof_dump_header_orig;
 
 	test_skip_if(!config_prof);
 
-	active = true;
-	assert_d_eq(mallctl("prof.active", NULL, NULL, &active, sizeof(active)),
-	    0, "Unexpected mallctl failure while activating profiling");
+	set_prof_active(true);
 
 	assert_zu_eq(prof_bt_count(), 0, "Expected 0 backtraces");
 	p = mallocx(1, 0);
@@ -133,9 +138,7 @@ TEST_BEGIN(test_prof_reset_cleanup)
 	dallocx(p, 0);
 	assert_zu_eq(prof_bt_count(), 0, "Expected 0 backtraces");
 
-	active = false;
-	assert_d_eq(mallctl("prof.active", NULL, NULL, &active, sizeof(active)),
-	    0, "Unexpected mallctl failure while deactivating profiling");
+	set_prof_active(false);
 }
 TEST_END
 
@@ -192,7 +195,6 @@ thd_start(void *varg)
 TEST_BEGIN(test_prof_reset)
 {
 	size_t lg_prof_sample_orig;
-	bool active;
 	thd_t thds[NTHREADS];
 	unsigned thd_args[NTHREADS];
 	unsigned i;
@@ -208,9 +210,7 @@ TEST_BEGIN(test_prof_reset)
 	lg_prof_sample_orig = get_lg_prof_sample();
 	do_prof_reset(5);
 
-	active = true;
-	assert_d_eq(mallctl("prof.active", NULL, NULL, &active, sizeof(active)),
-	    0, "Unexpected mallctl failure while activating profiling");
+	set_prof_active(true);
 
 	for (i = 0; i < NTHREADS; i++) {
 		thd_args[i] = i;
@@ -224,9 +224,7 @@ TEST_BEGIN(test_prof_reset)
 	assert_zu_eq(prof_tdata_count(), tdata_count,
 	    "Unexpected remaining tdata structures");
 
-	active = false;
-	assert_d_eq(mallctl("prof.active", NULL, NULL, &active, sizeof(active)),
-	    0, "Unexpected mallctl failure while deactivating profiling");
+	set_prof_active(false);
 
 	do_prof_reset(lg_prof_sample_orig);
 }
@@ -237,6 +235,58 @@ TEST_END
 #undef RESET_INTERVAL
 #undef DUMP_INTERVAL
 
+/* Test sampling at the same allocation site across resets. */
+#define	NITER 10
+TEST_BEGIN(test_xallocx)
+{
+	size_t lg_prof_sample_orig;
+	unsigned i;
+	void *ptrs[NITER];
+
+	test_skip_if(!config_prof);
+
+	lg_prof_sample_orig = get_lg_prof_sample();
+	set_prof_active(true);
+
+	/* Reset profiling. */
+	do_prof_reset(0);
+
+	for (i = 0; i < NITER; i++) {
+		void *p;
+		size_t sz, nsz;
+
+		/* Reset profiling. */
+		do_prof_reset(0);
+
+		/* Allocate small object (which will be promoted). */
+		p = ptrs[i] = mallocx(1, 0);
+		assert_ptr_not_null(p, "Unexpected mallocx() failure");
+
+		/* Reset profiling. */
+		do_prof_reset(0);
+
+		/* Perform successful xallocx(). */
+		sz = sallocx(p, 0);
+		assert_zu_eq(xallocx(p, sz, 0, 0), sz,
+		    "Unexpected xallocx() failure");
+
+		/* Perform unsuccessful xallocx(). */
+		nsz = nallocx(sz+1, 0);
+		assert_zu_eq(xallocx(p, nsz, 0, 0), sz,
+		    "Unexpected xallocx() success");
+	}
+
+	for (i = 0; i < NITER; i++) {
+		/* dallocx. */
+		dallocx(ptrs[i], 0);
+	}
+
+	set_prof_active(false);
+	do_prof_reset(lg_prof_sample_orig);
+}
+TEST_END
+#undef NITER
+
 int
 main(void)
 {
@@ -247,5 +297,6 @@ main(void)
 	return (test(
 	    test_prof_reset_basic,
 	    test_prof_reset_cleanup,
-	    test_prof_reset));
+	    test_prof_reset,
+	    test_xallocx));
 }