Add packing test, which verifies stable layout policy.
diff --git a/Makefile.in b/Makefile.in
index e4aaaf2..5e6f0c1 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -160,6 +160,7 @@
$(srcroot)test/unit/math.c \
$(srcroot)test/unit/mq.c \
$(srcroot)test/unit/mtx.c \
+ $(srcroot)test/unit/pack.c \
$(srcroot)test/unit/ph.c \
$(srcroot)test/unit/prng.c \
$(srcroot)test/unit/prof_accum.c \
diff --git a/test/unit/pack.c b/test/unit/pack.c
new file mode 100644
index 0000000..8071183
--- /dev/null
+++ b/test/unit/pack.c
@@ -0,0 +1,167 @@
+#include "test/jemalloc_test.h"
+
+/* Immediately purge to minimize fragmentation. */
+const char *malloc_conf = "decay_time:-1";
+
+/*
+ * Size class that is a divisor of the page size, ideally 4+ regions per run.
+ */
+#if LG_PAGE <= 14
+#define SZ (ZU(1) << (LG_PAGE - 2))
+#else
+#define SZ 4096
+#endif
+
+/*
+ * Number of slabs to consume at high water mark. Should be at least 2 so that
+ * if mmap()ed memory grows downward, downward growth of mmap()ed memory is
+ * tested.
+ */
+#define NSLABS 8
+
+static unsigned
+binind_compute(void)
+{
+ size_t sz;
+ unsigned nbins, i;
+
+ sz = sizeof(nbins);
+ assert_d_eq(mallctl("arenas.nbins", &nbins, &sz, NULL, 0), 0,
+ "Unexpected mallctl failure");
+
+ for (i = 0; i < nbins; i++) {
+ size_t mib[4];
+ size_t miblen = sizeof(mib)/sizeof(size_t);
+ size_t size;
+
+ assert_d_eq(mallctlnametomib("arenas.bin.0.size", mib,
+ &miblen), 0, "Unexpected mallctlnametomb failure");
+ mib[2] = (size_t)i;
+
+ sz = sizeof(size);
+ assert_d_eq(mallctlbymib(mib, miblen, &size, &sz, NULL, 0), 0,
+ "Unexpected mallctlbymib failure");
+ if (size == SZ)
+ return (i);
+ }
+
+ test_fail("Unable to compute nregs_per_run");
+ return (0);
+}
+
+static size_t
+nregs_per_run_compute(void)
+{
+ uint32_t nregs;
+ size_t sz;
+ unsigned binind = binind_compute();
+ size_t mib[4];
+ size_t miblen = sizeof(mib)/sizeof(size_t);
+
+ assert_d_eq(mallctlnametomib("arenas.bin.0.nregs", mib, &miblen), 0,
+ "Unexpected mallctlnametomb failure");
+ mib[2] = (size_t)binind;
+ sz = sizeof(nregs);
+ assert_d_eq(mallctlbymib(mib, miblen, &nregs, &sz, NULL,
+ 0), 0, "Unexpected mallctlbymib failure");
+ return (nregs);
+}
+
+static unsigned
+arenas_extend_mallctl(void)
+{
+ unsigned arena_ind;
+ size_t sz;
+
+ sz = sizeof(arena_ind);
+ assert_d_eq(mallctl("arenas.extend", &arena_ind, &sz, NULL, 0), 0,
+ "Error in arenas.extend");
+
+ return (arena_ind);
+}
+
+static void
+arena_reset_mallctl(unsigned arena_ind)
+{
+ size_t mib[3];
+ size_t miblen = sizeof(mib)/sizeof(size_t);
+
+ assert_d_eq(mallctlnametomib("arena.0.reset", mib, &miblen), 0,
+ "Unexpected mallctlnametomib() failure");
+ mib[1] = (size_t)arena_ind;
+ assert_d_eq(mallctlbymib(mib, miblen, NULL, NULL, NULL, 0), 0,
+ "Unexpected mallctlbymib() failure");
+}
+
+TEST_BEGIN(test_pack)
+{
+ unsigned arena_ind = arenas_extend_mallctl();
+ size_t nregs_per_run = nregs_per_run_compute();
+ size_t nregs = nregs_per_run * NSLABS;
+ VARIABLE_ARRAY(void *, ptrs, nregs);
+ size_t i, j, offset;
+
+ /* Fill matrix. */
+ for (i = offset = 0; i < NSLABS; i++) {
+ for (j = 0; j < nregs_per_run; j++) {
+ void *p = mallocx(SZ, MALLOCX_ARENA(arena_ind) |
+ MALLOCX_TCACHE_NONE);
+ assert_ptr_not_null(p,
+ "Unexpected mallocx(%zu, MALLOCX_ARENA(%u) |"
+ " MALLOCX_TCACHE_NONE) failure, run=%zu, reg=%zu",
+ SZ, arena_ind, i, j);
+ ptrs[(i * nregs_per_run) + j] = p;
+ }
+ }
+
+ /*
+ * Free all but one region of each run, but rotate which region is
+ * preserved, so that subsequent allocations exercise the within-run
+ * layout policy.
+ */
+ offset = 0;
+ for (i = offset = 0;
+ i < NSLABS;
+ i++, offset = (offset + 1) % nregs_per_run) {
+ for (j = 0; j < nregs_per_run; j++) {
+ void *p = ptrs[(i * nregs_per_run) + j];
+ if (offset == j)
+ continue;
+ dallocx(p, MALLOCX_ARENA(arena_ind) |
+ MALLOCX_TCACHE_NONE);
+ }
+ }
+
+ /*
+ * Logically refill matrix, skipping preserved regions and verifying
+ * that the matrix is unmodified.
+ */
+ offset = 0;
+ for (i = offset = 0;
+ i < NSLABS;
+ i++, offset = (offset + 1) % nregs_per_run) {
+ for (j = 0; j < nregs_per_run; j++) {
+ void *p;
+
+ if (offset == j)
+ continue;
+ p = mallocx(SZ, MALLOCX_ARENA(arena_ind) |
+ MALLOCX_TCACHE_NONE);
+ assert_ptr_eq(p, ptrs[(i * nregs_per_run) + j],
+ "Unexpected refill discrepancy, run=%zu, reg=%zu\n",
+ i, j);
+ }
+ }
+
+ /* Clean up. */
+ arena_reset_mallctl(arena_ind);
+}
+TEST_END
+
+int
+main(void)
+{
+
+ return (test(
+ test_pack));
+}
