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--- /dev/null
+++ libmalloc/libmalloc-317.40.8/tests/madvise.c
@@ -0,0 +1,383 @@
+#include <TargetConditionals.h>
+#include <darwintest.h>
+#include <sys/mman.h>
+#include <stdio.h>
+#include <malloc/malloc.h>
+#include <mach/vm_page_size.h>
+#include <stdlib.h>
+
+#include "base.h"
+#include "platform.h"
+#include "nano_zone_common.h"
+#include "nano_zone.h"
+
+extern int
+malloc_engaged_nano(void);
+
+#define T_EXPECT_BYTES(p, len, byte, msg, ...) do { \
+ char *_p = (char *)(p); \
+ bool bytes = true; \
+ for (int i=0; i<len; i++) { \
+ T_QUIET; T_EXPECT_EQ_CHAR(*(_p+i), byte, "*(%p+0x%x)", _p, i); \
+ if (*(_p+i) != byte) { bytes = false; break; } \
+ } \
+ T_EXPECT_TRUE(bytes, msg, ## __VA_ARGS__); \
+} while(0)
+
+// vm.madvise_free_debug should cause the kernel to forcibly discard
+// pages that are madvised when the call is made. Making testing
+// madvise behaviour predictable under test.
+T_DECL(madvise_free_debug, "test vm.madvise_free_debug",
+ T_META_SYSCTL_INT("vm.madvise_free_debug=1"),
+ T_META_ASROOT(YES))
+{
+ // Map 32k of memory.
+ size_t memsz = 32 * vm_page_size;
+ void *mem = mmap(NULL, memsz, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, 0, 0);
+ T_EXPECT_NE_PTR(mem, MAP_FAILED, "mapped pages should not be MAP_FAILED");
+
+ // Fill it with scribble.
+ memset(mem, 0xa, 32 * vm_page_size);
+
+ // Madvise a specfic page.
+ T_EXPECT_POSIX_ZERO(
+ madvise(mem + (4 * vm_page_size), vm_page_size, MADV_FREE_REUSABLE),
+ "madvise (mem + 4 pages)");
+
+ // Check the entire page is empty.
+ T_EXPECT_BYTES(mem + (4 * vm_page_size), vm_page_size, 0x0, "madvise'd memory is all zeros");
+ T_EXPECT_POSIX_SUCCESS(munmap(mem, memsz), "munmap");
+}
+
+T_DECL(subpage_madvise_free_debug, "test vm.madvise_free_debug",
+ T_META_SYSCTL_INT("vm.madvise_free_debug=1"),
+ T_META_ASROOT(YES))
+{
+ // Skip if we dont' have vm_kernel_page_size < vm_page_size
+ if (vm_kernel_page_size >= vm_page_size) {
+ T_SKIP("vm_kernel_page_size >= vm_page_size, skipping subpage tests");
+ return;
+ }
+
+ // Map 32k of memory.
+ size_t memsz = 32 * vm_page_size;
+ void *mem = mmap(NULL, memsz, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, 0, 0);
+ T_EXPECT_NE_PTR(mem, MAP_FAILED, "mapped pages should not be MAP_FAILED");
+
+ // Fill it with scribble.
+ memset(mem, 0xa, 32 * vm_page_size);
+
+ // Madvise a specfic page.
+ T_EXPECT_POSIX_ZERO(
+ madvise(mem + (4 * vm_kernel_page_size), vm_kernel_page_size, MADV_FREE_REUSABLE),
+ "madvise (mem + 4 pages)");
+
+ // Check the entire page is empty.
+ T_EXPECT_BYTES(mem + (4 * vm_kernel_page_size), vm_kernel_page_size, 0x0, "madvise'd memory is all zeros");
+
+ // Check that the subsequent page is 0xaa.
+ T_EXPECT_BYTES(mem + (5 * vm_kernel_page_size), vm_kernel_page_size, 0xa, "un-madvise'd memory is all 0xaa");
+
+ T_EXPECT_POSIX_SUCCESS(munmap(mem, memsz), "munmap");
+}
+
+// <rdar://problem/31844360> disable nano_subpage_madvise due to consistent
+// failures.
+#if 0
+
+T_DECL(nano_subpage_madvise, "nano allocator madvise",
+ T_META_SYSCTL_INT("vm.madvise_free_debug=1"),
+ T_META_ENVVAR("MallocNanoZone=1"),
+ T_META_CHECK_LEAKS(NO),
+ T_META_ASROOT(YES))
+{
+ T_EXPECT_TRUE(malloc_engaged_nano(), "nano zone enabled");
+
+ void *ptr = malloc(128);
+ T_EXPECT_EQ_PTR(
+ (void *)(((uintptr_t)ptr) >> (64-NANO_SIGNATURE_BITS)),
+ (void *)NANOZONE_SIGNATURE,
+ "malloc == nano allocation");
+ free(ptr);
+
+ const size_t granularity = 128;
+ const size_t allocations = 128 * 1024;
+
+ void *bank[allocations / granularity];
+ for (int i=0; i<(sizeof(bank)/sizeof(*bank)); i++) {
+ // allocate 128k of memory, scribble them
+ bank[i] = malloc(granularity);
+ memset(bank[i], 'A', granularity);
+ }
+
+ ptr = NULL;
+ size_t limit = vm_kernel_page_size;
+ for (int i=0; i<256; i++) {
+ // find the first entry that lies on the user page
+ // boundary, rather than kernel, to try and find
+ // bugs where we accidentally round up to other page
+ // sizes.
+ if (!ptr && trunc_page((uintptr_t)bank[i]) != (uintptr_t)bank[i]) {
+ continue;
+ }
+
+ // mark active, free the entry, then decrement the
+ // limit until we get to a full page.
+ if (!ptr) {
+ ptr = bank[i];
+ }
+
+ free(bank[i]);
+ bank[i] = NULL;
+ limit -= 128;
+
+ if (limit == 0) {
+ // finished, break.
+ break;
+ }
+ }
+
+ // force the nano alloc to madvise things
+ malloc_zone_pressure_relief(malloc_default_zone(), 0);
+
+ // we should be able to test for the entire range that's
+ // madvised being zeros now.
+ T_EXPECT_BYTES(ptr, vm_kernel_page_size, 0x0,
+ "madvised region was cleared");
+
+ // and that the page immediately after the kernel page is
+ // stil intacted.
+ T_EXPECT_BYTES(ptr + vm_kernel_page_size, vm_kernel_page_size, 'A',
+ "non-madvised page check");
+
+ for (int i=0; i<(sizeof(bank)/sizeof(*bank)); i++) {
+ free(bank[i]);
+ }
+}
+
+#endif
+
+#if 0
+// OS X has the recirc depot enabled, so more has to be done to reliably test
+// madvise on that platform.
+
+T_DECL(tiny_subpage_madvise, "tiny allocator madvise",
+ T_META_SYSCTL_INT("vm.madvise_free_debug=1"),
+ T_META_ENVVAR("MallocNanoZone=0"),
+ T_META_ASROOT(YES))
+{
+ T_EXPECT_TRUE(!malloc_engaged_nano(), "nano zone disabled");
+
+ malloc_zone_t *zone = malloc_create_zone(0, 0);
+
+ const size_t granularity = 16;
+ const size_t allocations = 128 * 1024;
+
+ void *bank[allocations / granularity];
+ for (int i=0; i<(sizeof(bank)/sizeof(*bank)); i++) {
+ // allocate 128k of memory, scribble them
+ bank[i] = malloc_zone_malloc(zone, granularity);
+ memset(bank[i], 'A', granularity);
+ printf("%p\n", bank[i]);
+
+ if (i>0) {
+ T_QUIET;
+ T_ASSERT_EQ_PTR(((uintptr_t)bank[i-1]) + granularity,
+ (uintptr_t)bank[i],
+ "contiguous allocations required");
+ }
+ }
+
+ void *ptr = NULL;
+ size_t num_needed = vm_kernel_page_size / granularity + 1;
+
+ for (int i=1; i<(sizeof(bank)/sizeof(*bank)); i++) {
+ // find the first page aligned entry
+ if (!ptr &&
+ ((uintptr_t)bank[i] > round_page_kernel((uintptr_t)bank[i]) ||
+ (uintptr_t)bank[i] + granularity - 1 < round_page_kernel((uintptr_t)bank[i])))
+ {
+ continue;
+ }
+
+ // when we find the entry, take this pointer and
+ // also free the entry before.
+ if (!ptr) {
+ ptr = (void *)round_page_kernel((uintptr_t)bank[i]);
+ }
+
+ malloc_zone_free(zone, bank[i]);
+ bank[i] = NULL;
+ num_needed--;
+
+ if (num_needed == 0) {
+ break;
+ }
+ }
+
+ T_ASSERT_NOTNULL(ptr, "expected pointer");
+
+ // we should be able to test for the entire range that's
+ // madvised being zeros now.
+ T_EXPECT_BYTES(ptr, vm_kernel_page_size, 0x0,
+ "madvised region was cleared");
+
+ // and that the page immediately after the kernel page is
+ // stil intacted.
+ T_EXPECT_BYTES(ptr + vm_kernel_page_size + granularity, vm_kernel_page_size, 'A',
+ "non-madvised page check");
+
+ for (int i=0; i<(sizeof(bank)/sizeof(*bank)); i++) {
+ malloc_zone_free(zone, bank[i]);
+ }
+}
+
+T_DECL(small_subpage_madvise, "small allocator madvise",
+ T_META_SYSCTL_INT("vm.madvise_free_debug=1"),
+ T_META_ENVVAR("MallocNanoZone=0"))
+{
+ T_EXPECT_TRUE(!malloc_engaged_nano(), "nano zone disabled");
+
+ const size_t granularity = 512;
+ const size_t allocations = 128 * 1024;
+
+ void *bank[allocations / granularity];
+ for (int i=0; i<(sizeof(bank)/sizeof(*bank)); i++) {
+ // allocate 128k of memory, scribble them
+ bank[i] = malloc(granularity);
+ memset(bank[i], 'A', granularity);
+ }
+
+ void *ptr = NULL;
+ size_t num_needed = vm_kernel_page_size / granularity + 1;
+
+ for (int i=1; i<(sizeof(bank)/sizeof(*bank)); i++) {
+ // find the first page aligned entry
+ if (!ptr &&
+ ((uintptr_t)bank[i] > round_page_kernel((uintptr_t)bank[i]) ||
+ (uintptr_t)bank[i] + granularity - 1 < round_page_kernel((uintptr_t)bank[i])))
+ {
+ continue;
+ }
+
+ // when we find the entry, take this pointer and
+ // also free the entry before.
+ if (!ptr) {
+ ptr = (void *)round_page_kernel((uintptr_t)bank[i]);
+ }
+
+ free(bank[i]);
+ bank[i] = NULL;
+ num_needed--;
+
+ if (num_needed == 0) {
+ break;
+ }
+ }
+
+ T_ASSERT_NOTNULL(ptr, "expected pointer");
+
+ // we should be able to test for the entire range that's
+ // madvised being zeros now.
+ T_EXPECT_BYTES(ptr, vm_kernel_page_size, 0x0,
+ "madvised region was cleared");
+
+ // and that the page immediately after the kernel page is
+ // stil intacted.
+ T_EXPECT_BYTES(ptr + vm_kernel_page_size + granularity, vm_kernel_page_size, 'A',
+ "non-madvised page check");
+
+ for (int i=0; i<(sizeof(bank)/sizeof(*bank)); i++) {
+ free(bank[i]);
+ }
+}
+#endif // #if 0
+
+static void
+test_aggressive_madvise(const vm_size_t total_size, const size_t granularity)
+{
+ void *bank[total_size / granularity];
+
+ for (int i = 0; i < (sizeof(bank)/sizeof(*bank)); i++) {
+ bank[i] = malloc(granularity);
+ memset(bank[i], 'A', granularity);
+ }
+
+ // free all allocations to force as much as possible to be madvise'd
+ for (int i = 0; i < (sizeof(bank)/sizeof(*bank)); i++) {
+ free(bank[i]);
+ }
+
+ // find the first page aligned allocation that has
+ // continguous allocations after it that total an entire page
+ void *ptr = NULL;
+ void *next_ptr = NULL;
+ int num_needed = -1;
+ for (int i = 0; i < (sizeof(bank)/sizeof(*bank)); i++) {
+ if (ptr) {
+ if (bank[i] == next_ptr) {
+ num_needed--;
+
+ if (num_needed == 0) {
+ // found an entire page that should be free
+ break;
+ }
+ } else {
+ // start search again because there was a non-contiguous allocation
+ ptr = NULL;
+ }
+ }
+
+ if (!ptr && round_page((uintptr_t)bank[i]) == (uintptr_t)bank[i]) {
+ // start a new search at this page aligned allocation
+ ptr = next_ptr = bank[i];
+ num_needed = ((vm_kernel_page_size + granularity - 1) / granularity) - 1;
+
+ if (num_needed == 0) {
+ // granularity is greater than or equal to a page
+ break;
+ }
+ }
+
+ if (ptr) {
+ next_ptr = (void *)((uintptr_t)next_ptr + granularity);
+ }
+ }
+
+ T_ASSERT_NOTNULL(ptr, "expected pointer");
+ T_ASSERT_EQ(num_needed, 0, "need entire page");
+
+ // Check the entire page-aligned range is empty.
+ T_EXPECT_BYTES(ptr, vm_page_size, 0x0, "madvise'd memory is all zeros");
+}
+
+T_DECL(tiny_aggressive_madvise, "tiny allocator free with MallocAggressiveMadvise=1",
+ T_META_SYSCTL_INT("vm.madvise_free_debug=1"),
+ T_META_ENVVAR("MallocNanoZone=0"),
+ T_META_ENVVAR("MallocAggressiveMadvise=1"),
+ T_META_ENABLED(CONFIG_AGGRESSIVE_MADVISE),
+ T_META_ASROOT(YES))
+{
+ test_aggressive_madvise(vm_page_size * 4, 16);
+}
+
+T_DECL(small_aggressive_madvise, "small allocator free with MallocAggressiveMadvise=1",
+ T_META_SYSCTL_INT("vm.madvise_free_debug=1"),
+ T_META_ENVVAR("MallocAggressiveMadvise=1"),
+ T_META_ENABLED(CONFIG_AGGRESSIVE_MADVISE),
+ T_META_ASROOT(YES))
+{
+ test_aggressive_madvise(vm_page_size * 8, 1536);
+}
+
+T_DECL(medium_aggressive_madvise, "medium allocator free with MallocAggressiveMadvise=1",
+ T_META_SYSCTL_INT("vm.madvise_free_debug=1"),
+ T_META_ENVVAR("MallocMediumZone=1"),
+ T_META_ENVVAR("MallocMediumActivationThreshold=1"),
+ T_META_ENVVAR("MallocAggressiveMadvise=1"),
+ T_META_ENABLED(CONFIG_MEDIUM_ALLOCATOR),
+ T_META_ENABLED(CONFIG_AGGRESSIVE_MADVISE),
+ T_META_ASROOT(YES))
+{
+ test_aggressive_madvise(16 * 64 * 1024, 64 * 1024);
+}