src/tscore/JeMiAllocator.cc

/** @file

  @section license License

  Licensed to the Apache Software Foundation (ASF) under one
  or more contributor license agreements.  See the NOTICE file
  distributed with this work for additional information
  regarding copyright ownership.  The ASF licenses this file
  to you under the Apache License, Version 2.0 (the
  "License"); you may not use this file except in compliance
  with the License.  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
 */

#include <unistd.h>
#include <sys/types.h>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include "tscore/ink_memory.h"
#include "tscore/ink_error.h"
#include "tscore/ink_assert.h"
#include "tscore/ink_align.h"
#include "tscore/JeMiAllocator.h"
#include "tscore/Diags.h"

namespace je_mi_malloc
{
#if JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED
thread_local extent_alloc_t *JeMiNodumpAllocator::original_alloc = nullptr;
thread_local extent_hooks_t  JeMiNodumpAllocator::extent_hooks;
thread_local int             JeMiNodumpAllocator::arena_flags = 0;

void *
JeMiNodumpAllocator::alloc(extent_hooks_t *extent, void *new_addr, size_t size, size_t alignment, bool *zero, bool *commit,
                           unsigned int arena_id)
{
  void *result = original_alloc(extent, new_addr, size, alignment, zero, commit, arena_id);

  if (result != nullptr) {
    // Seems like we don't really care if the advice went through
    // in the original code, so just keeping it the same here.
    ats_madvise((caddr_t)result, size, MADV_DONTDUMP);
  }

  return result;
}

int
JeMiNodumpAllocator::extend_and_setup_arena()
{
  unsigned int arena_id;
  size_t       arena_id_len = sizeof(arena_id);
  if (auto ret = mallctl("arenas.create", &arena_id, &arena_id_len, nullptr, 0)) {
    ink_abort("Unable to extend arena: %s", std::strerror(ret));
  }

  int flags = MALLOCX_ARENA(arena_id) | MALLOCX_TCACHE_NONE;

  // Read the existing hooks
  const auto      key = "arena." + std::to_string(arena_id) + ".extent_hooks";
  extent_hooks_t *hooks;
  size_t          hooks_len = sizeof(hooks);
  if (auto ret = mallctl(key.c_str(), &hooks, &hooks_len, nullptr, 0)) {
    ink_abort("Unable to get the hooks: %s", std::strerror(ret));
  }

  // Set the custom hook
  original_alloc     = hooks->alloc;
  extent_hooks       = *hooks;
  extent_hooks.alloc = &JeMiNodumpAllocator::alloc;

  extent_hooks_t *new_hooks = &extent_hooks;
  if (auto ret = mallctl(key.c_str(), nullptr, nullptr, &new_hooks, sizeof(new_hooks))) {
    ink_abort("Unable to set the hooks: %s", std::strerror(ret));
  }

  Debug("JeAllocator", "arena \"%ud\" created with flags \"%d\"", arena_id, flags);

  arena_flags = flags;

  return flags;
}
#elif MIMALLOC_NODUMP_ALLOCATOR_SUPPORTED
thread_local mi_heap_t *JeMiNodumpAllocator::nodump_heap = nullptr;
#endif /* JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED */

/**
 * This will retain the original functionality if
 * !defined(JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED)
 */
void *
JeMiNodumpAllocator::allocate(InkFreeList *f)
{
#if JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED
  int flags = arena_flags;
  if (unlikely(flags == 0)) {
    flags = extend_and_setup_arena();
  }
#elif MIMALLOC_NODUMP_ALLOCATOR_SUPPORTED
  if (unlikely(nodump_heap == nullptr)) {
    nodump_heap = mi_heap_new();
    if (unlikely(nodump_heap == nullptr)) {
      ink_abort("couldn't create new mimalloc heap");
    }
  }
#endif

  void *newp = nullptr;
  if (f->advice) {
#if JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED
    if (likely(f->type_size > 0)) {
      flags |= MALLOCX_ALIGN(f->alignment);
      if (unlikely((newp = mallocx(f->type_size, flags)) == nullptr)) {
        ink_abort("couldn't allocate %u bytes", f->type_size);
      }
    }
#elif MIMALLOC_NODUMP_ALLOCATOR_SUPPORTED
    if (likely(f->type_size > 0)) {
      if (unlikely((newp = mi_heap_malloc_aligned(nodump_heap, f->type_size, f->alignment)) == nullptr)) {
        ink_abort("couldn't allocate %u bytes", f->type_size);
      }
      ats_madvise(static_cast<caddr_t>(newp), f->type_size, f->advice);
    }
#else
    newp = ats_memalign(f->alignment, f->type_size);
    if (INK_ALIGN((uint64_t)newp, ats_pagesize()) == (uint64_t)newp) {
      ats_madvise(static_cast<caddr_t>(newp), INK_ALIGN(f->type_size, f->alignment), f->advice);
    }
#endif
  } else {
    newp = ats_memalign(f->alignment, f->type_size);
  }
  return newp;
}

void
JeMiNodumpAllocator::deallocate(InkFreeList *f, void *ptr)
{
  if (f->advice) {
#if JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED
    if (likely(ptr)) {
      dallocx(ptr, MALLOCX_TCACHE_NONE);
    }
#elif MIMALLOC_NODUMP_ALLOCATOR_SUPPORTED
    if (likely(ptr)) {
      mi_free(ptr);
    }
#else
    ats_free(ptr);
#endif
  } else {
    ats_free(ptr);
  }
}

JeMiNodumpAllocator &
globalJeMiNodumpAllocator()
{
  static auto instance = new JeMiNodumpAllocator();
  return *instance;
}

} // namespace je_mi_malloc