MDEV-32791 MariaDB cannot be installed on Red Hat ubi9

The libpmem dependency that had been added in
commit 3daef523 (MDEV-17084)
did not achieve any measurable performance improvement when
comparing the same PMEM device with and without "mount -o dax"
using the Linux ext4 file system.

Because Red Hat has deprecated libpmem, let us remove the code
altogether.

Note: This is a 10.6 version of
commit 3f9f5ca4
which will retain PMEM support in MariaDB Server 10.11.

cmake/FindPMEM.cmake

-if(PMEM_LIBRARIES)
-  set(PMEM_FOUND TRUE)
-  return()
-endif()
-if(DEFINED PMEM_LIBRARIES)
-  set(PMEM_FOUND FALSE)
-  return()
-endif()
-
-find_path(PMEM_INCLUDE_DIR NAMES libpmem.h)
-find_library(PMEM_LIBRARIES NAMES pmem)
-
-include(FindPackageHandleStandardArgs)
-FIND_PACKAGE_HANDLE_STANDARD_ARGS(
-    PMEM DEFAULT_MSG
-    PMEM_LIBRARIES PMEM_INCLUDE_DIR)
-
-mark_as_advanced(PMEM_INCLUDE_DIR PMEM_LIBRARIES)

debian/autobake-deb.sh

@@ -61,12 +61,6 @@ replace_uring_with_aio()
       -e '/-DWITH_URING=ON/d' -i debian/rules
 }
 
-disable_pmem()
-{
-  sed '/libpmem-dev/d' -i debian/control
-  sed '/-DWITH_PMEM=ON/d' -i debian/rules
-}
-
 architecture=$(dpkg-architecture -q DEB_BUILD_ARCH)
 
 # Parse release name and number from Linux standard base release
@@ -99,18 +93,10 @@ in
   # Debian
   "buster")
     replace_uring_with_aio
-    if [ ! "$architecture" = amd64 ]
-    then
-      disable_pmem
-    fi
     ;&
   "bullseye"|"bookworm")
     # mariadb-plugin-rocksdb in control is 4 arches covered by the distro rocksdb-tools
     # so no removal is necessary.
-    if [[ ! "$architecture" =~ amd64|arm64|ppc64el ]]
-    then
-      disable_pmem
-    fi
     if [[ ! "$architecture" =~ amd64|arm64|armel|armhf|i386|mips64el|mipsel|ppc64el|s390x ]]
     then
       replace_uring_with_aio
@@ -132,10 +118,6 @@ in
     then
       remove_rocksdb_tools
     fi
-    if [[ ! "$architecture" =~ amd64|arm64|ppc64el ]]
-    then
-      disable_pmem
-    fi
     if [[ ! "$architecture" =~ amd64|arm64|armhf|ppc64el|s390x ]]
     then
       replace_uring_with_aio

debian/control

@@ -30,7 +30,6 @@ Build-Depends: bison,
                libnuma-dev [linux-any],
                libpam0g-dev,
                libpcre2-dev,
-               libpmem-dev [amd64 arm64 ppc64el riscv64],
                libsnappy-dev,
                libssl-dev,
                libssl-dev:native,

debian/rules

@@ -49,12 +49,6 @@ ifeq (32,$(DEB_HOST_ARCH_BITS))
     CMAKEFLAGS += -DPLUGIN_ROCKSDB=NO
 endif
 
-# Only attempt to build with PMEM on archs that have package libpmem-dev available
-# See https://packages.debian.org/search?searchon=names&keywords=libpmem-dev
-ifneq (,$(filter $(DEB_HOST_ARCH),amd64 arm64 ppc64el riscv64))
-    CMAKEFLAGS += -DWITH_PMEM=ON
-endif
-
 # Add support for verbose builds
 MAKEFLAGS += VERBOSE=1
 

storage/innobase/CMakeLists.txt

@@ -439,24 +439,11 @@ SET(INNOBASE_SOURCES
 	ut/ut0vec.cc
 	ut/ut0wqueue.cc)
 
-OPTION(WITH_PMEM "Support redo log in persistent memory" OFF)
-FIND_PACKAGE(PMEM)
-IF(PMEM_FOUND)
-  INCLUDE_DIRECTORIES(${PMEM_INCLUDES})
-  ADD_COMPILE_FLAGS(log/log0log.cc COMPILE_FLAGS "-DHAVE_PMEM")
-  SET(PMEM_LIBRARY ${PMEM_LIBRARIES})
-ELSE()
-  IF(WITH_PMEM)
-    MESSAGE(FATAL_ERROR "WITH_PMEM=ON cannot be satisfied")
-  ENDIF()
-ENDIF()
-
 MYSQL_ADD_PLUGIN(innobase ${INNOBASE_SOURCES} STORAGE_ENGINE
   MODULE_OUTPUT_NAME ha_innodb
   DEFAULT RECOMPILE_FOR_EMBEDDED
   LINK_LIBRARIES
 	${ZLIB_LIBRARY}
-	${PMEM_LIBRARY}
 	${NUMA_LIBRARY}
 	${LIBSYSTEMD}
 	${LINKER_SCRIPT})

storage/innobase/log/log0log.cc

@@ -295,125 +295,11 @@ dberr_t file_os_io::flush() noexcept
   return os_file_flush(m_fd) ? DB_SUCCESS : DB_ERROR;
 }
 
-#ifdef HAVE_PMEM
-
-#include <libpmem.h>
-
-/** Memory mapped file */
-class mapped_file_t
-{
-public:
-  mapped_file_t()= default;
-  mapped_file_t(const mapped_file_t &)= delete;
-  mapped_file_t &operator=(const mapped_file_t &)= delete;
-  mapped_file_t(mapped_file_t &&)= delete;
-  mapped_file_t &operator=(mapped_file_t &&)= delete;
-  ~mapped_file_t() noexcept;
-
-  dberr_t map(const char *path, bool read_only= false,
-              bool nvme= false) noexcept;
-  dberr_t unmap() noexcept;
-  byte *data() noexcept { return m_area.data(); }
-
-private:
-  span<byte> m_area;
-};
-
-mapped_file_t::~mapped_file_t() noexcept
-{
-  if (!m_area.empty())
-    unmap();
-}
-
-dberr_t mapped_file_t::map(const char *path, bool read_only,
-                           bool nvme) noexcept
-{
-  auto fd= mysql_file_open(innodb_log_file_key, path,
-                           read_only ? O_RDONLY : O_RDWR, MYF(MY_WME));
-  if (fd == -1)
-    return DB_ERROR;
-
-  const auto file_size= size_t{os_file_get_size(path).m_total_size};
-
-  const int nvme_flag= nvme ? MAP_SYNC : 0;
-  void *ptr=
-      my_mmap(0, file_size, read_only ? PROT_READ : PROT_READ | PROT_WRITE,
-              MAP_SHARED_VALIDATE | nvme_flag, fd, 0);
-  mysql_file_close(fd, MYF(MY_WME));
-
-  if (ptr == MAP_FAILED)
-    return DB_ERROR;
-
-  m_area= {static_cast<byte *>(ptr), file_size};
-  return DB_SUCCESS;
-}
-
-dberr_t mapped_file_t::unmap() noexcept
-{
-  ut_ad(!m_area.empty());
-
-  if (my_munmap(m_area.data(), m_area.size()))
-    return DB_ERROR;
-
-  m_area= {};
-  return DB_SUCCESS;
-}
-
-static bool is_pmem(const char *path) noexcept
-{
-  mapped_file_t mf;
-  return mf.map(path, true, true) == DB_SUCCESS ? true : false;
-}
-
-class file_pmem_io final : public file_io
-{
-public:
-  file_pmem_io() noexcept : file_io(true) {}
-
-  dberr_t open(const char *path, bool read_only) noexcept final
-  {
-    return m_file.map(path, read_only, true);
-  }
-  dberr_t rename(const char *old_path, const char *new_path) noexcept final
-  {
-    return os_file_rename(innodb_log_file_key, old_path, new_path) ? DB_SUCCESS
-                                                                   : DB_ERROR;
-  }
-  dberr_t close() noexcept final { return m_file.unmap(); }
-  __attribute__((warn_unused_result))
-  dberr_t read(os_offset_t offset, span<byte> buf) noexcept final
-  {
-    memcpy(buf.data(), m_file.data() + offset, buf.size());
-    return DB_SUCCESS;
-  }
-  dberr_t write(const char *, os_offset_t offset,
-                span<const byte> buf) noexcept final
-  {
-    pmem_memcpy_persist(m_file.data() + offset, buf.data(), buf.size());
-    return DB_SUCCESS;
-  }
-  dberr_t flush() noexcept final
-  {
-    ut_ad(0);
-    return DB_SUCCESS;
-  }
-
-private:
-  mapped_file_t m_file;
-};
-#endif
-
 dberr_t log_file_t::open(bool read_only) noexcept
 {
   ut_a(!is_opened());
 
-#ifdef HAVE_PMEM
-  auto ptr= is_pmem(m_path.c_str())
-                ? std::unique_ptr<file_io>(new file_pmem_io)
-                : std::unique_ptr<file_io>(new file_os_io);
-#else
   auto ptr= std::unique_ptr<file_io>(new file_os_io);
-#endif
 
   if (dberr_t err= ptr->open(m_path.c_str(), read_only))
     return err;