mozilla-aarch64-48bit-va.patch
branchfirefox48
changeset 929 9fc2ebe6d7f1
parent 928 4663386a04de
child 930 fdfd88b0c2d7
--- a/mozilla-aarch64-48bit-va.patch	Mon Sep 19 21:47:49 2016 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,170 +0,0 @@
-
-# HG changeset patch
-# User Zheng Xu <zheng.xu@linaro.org>
-# Date 1464657720 -7200
-# Node ID dfaafbaaa2919a033c4c0abdd5830f4ea413bed6
-# Parent  499f16ca85ec48d1896a1633730715f32bd62140
-Bug 1143022 - Manually mmap on arm64 to ensure high 17 bits are clear. r=ehoogeveen
-
-There might be 48-bit VA on arm64 depending on kernel configuration.
-Manually mmap heap memory to align with the assumption made by JS engine.
-
-diff --git a/js/src/gc/Memory.cpp b/js/src/gc/Memory.cpp
---- a/js/src/gc/Memory.cpp
-+++ b/js/src/gc/Memory.cpp
-@@ -430,17 +430,17 @@ InitMemorySubsystem()
-     if (pageSize == 0)
-         pageSize = allocGranularity = size_t(sysconf(_SC_PAGESIZE));
- }
- 
- static inline void*
- MapMemoryAt(void* desired, size_t length, int prot = PROT_READ | PROT_WRITE,
-             int flags = MAP_PRIVATE | MAP_ANON, int fd = -1, off_t offset = 0)
- {
--#if defined(__ia64__) || (defined(__sparc64__) && defined(__NetBSD__))
-+#if defined(__ia64__) || (defined(__sparc64__) && defined(__NetBSD__)) || defined(__aarch64__)
-     MOZ_ASSERT(0xffff800000000000ULL & (uintptr_t(desired) + length - 1) == 0);
- #endif
-     void* region = mmap(desired, length, prot, flags, fd, offset);
-     if (region == MAP_FAILED)
-         return nullptr;
-     /*
-      * mmap treats the given address as a hint unless the MAP_FIXED flag is
-      * used (which isn't usually what you want, as this overrides existing
-@@ -480,16 +480,51 @@ MapMemory(size_t length, int prot = PROT
-      * as out of memory.
-      */
-     if ((uintptr_t(region) + (length - 1)) & 0xffff800000000000) {
-         if (munmap(region, length))
-             MOZ_ASSERT(errno == ENOMEM);
-         return nullptr;
-     }
-     return region;
-+#elif defined(__aarch64__)
-+   /*
-+    * There might be similar virtual address issue on arm64 which depends on
-+    * hardware and kernel configurations. But the work around is slightly
-+    * different due to the different mmap behavior.
-+    *
-+    * TODO: Merge with the above code block if this implementation works for
-+    * ia64 and sparc64.
-+    */
-+    const uintptr_t start = UINT64_C(0x0000070000000000);
-+    const uintptr_t end   = UINT64_C(0x0000800000000000);
-+    const uintptr_t step  = ChunkSize;
-+   /*
-+    * Optimization options if there are too many retries in practice:
-+    * 1. Examine /proc/self/maps to find an available address. This file is
-+    *    not always available, however. In addition, even if we examine
-+    *    /proc/self/maps, we may still need to retry several times due to
-+    *    racing with other threads.
-+    * 2. Use a global/static variable with lock to track the addresses we have
-+    *    allocated or tried.
-+    */
-+    uintptr_t hint;
-+    void* region = MAP_FAILED;
-+    for (hint = start; region == MAP_FAILED && hint + length <= end; hint += step) {
-+        region = mmap((void*)hint, length, prot, flags, fd, offset);
-+        if (region != MAP_FAILED) {
-+            if ((uintptr_t(region) + (length - 1)) & 0xffff800000000000) {
-+                if (munmap(region, length)) {
-+                    MOZ_ASSERT(errno == ENOMEM);
-+                }
-+                region = MAP_FAILED;
-+            }
-+        }
-+    }
-+    return region == MAP_FAILED ? nullptr : region;
- #else
-     void* region = MozTaggedAnonymousMmap(nullptr, length, prot, flags, fd, offset, "js-gc-heap");
-     if (region == MAP_FAILED)
-         return nullptr;
-     return region;
- #endif
- }
- 
-diff --git a/js/src/jsapi-tests/testGCAllocator.cpp b/js/src/jsapi-tests/testGCAllocator.cpp
---- a/js/src/jsapi-tests/testGCAllocator.cpp
-+++ b/js/src/jsapi-tests/testGCAllocator.cpp
-@@ -307,48 +307,72 @@ void* mapMemoryAt(void* desired, size_t 
- void* mapMemory(size_t length) { return nullptr; }
- void unmapPages(void* p, size_t size) { }
- 
- #elif defined(XP_UNIX)
- 
- void*
- mapMemoryAt(void* desired, size_t length)
- {
--#if defined(__ia64__) || (defined(__sparc64__) && defined(__NetBSD__))
-+#if defined(__ia64__) || (defined(__sparc64__) && defined(__NetBSD__)) || defined(__aarch64__)
-     MOZ_RELEASE_ASSERT(0xffff800000000000ULL & (uintptr_t(desired) + length - 1) == 0);
- #endif
-     void* region = mmap(desired, length, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
-     if (region == MAP_FAILED)
-         return nullptr;
-     if (region != desired) {
-         if (munmap(region, length))
-             MOZ_RELEASE_ASSERT(errno == ENOMEM);
-         return nullptr;
-     }
-     return region;
- }
- 
- void*
- mapMemory(size_t length)
- {
--    void* hint = nullptr;
-+    int prot = PROT_READ | PROT_WRITE;
-+    int flags = MAP_PRIVATE | MAP_ANON;
-+    int fd = -1;
-+    off_t offset = 0;
-+    // The test code must be aligned with the implementation in gc/Memory.cpp.
- #if defined(__ia64__) || (defined(__sparc64__) && defined(__NetBSD__))
--    hint = (void*)0x0000070000000000ULL;
--#endif
--    void* region = mmap(hint, length, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
-+    void* region = mmap((void*)0x0000070000000000, length, prot, flags, fd, offset);
-     if (region == MAP_FAILED)
-         return nullptr;
--#if defined(__ia64__) || (defined(__sparc64__) && defined(__NetBSD__))
--    if ((uintptr_t(region) + (length - 1)) & 0xffff800000000000ULL) {
-+    if ((uintptr_t(region) + (length - 1)) & 0xffff800000000000) {
-         if (munmap(region, length))
-             MOZ_RELEASE_ASSERT(errno == ENOMEM);
-         return nullptr;
-     }
-+    return region;
-+#elif defined(__aarch64__)
-+    const uintptr_t start = UINT64_C(0x0000070000000000);
-+    const uintptr_t end   = UINT64_C(0x0000800000000000);
-+    const uintptr_t step  = ChunkSize;
-+    uintptr_t hint;
-+    void* region = MAP_FAILED;
-+    for (hint = start; region == MAP_FAILED && hint + length <= end; hint += step) {
-+        region = mmap((void*)hint, length, prot, flags, fd, offset);
-+        if (region != MAP_FAILED) {
-+            if ((uintptr_t(region) + (length - 1)) & 0xffff800000000000) {
-+                if (munmap(region, length)) {
-+                    MOZ_RELEASE_ASSERT(errno == ENOMEM);
-+                }
-+                region = MAP_FAILED;
-+            }
-+        }
-+    }
-+    return region == MAP_FAILED ? nullptr : region;
-+#else
-+    void* region = mmap(nullptr, length, prot, flags, fd, offset);
-+    if (region == MAP_FAILED)
-+        return nullptr;
-+    return region;
- #endif
--    return region;
- }
- 
- void
- unmapPages(void* p, size_t size)
- {
-     if (munmap(p, size))
-         MOZ_RELEASE_ASSERT(errno == ENOMEM);
- }
-