mm: memblock: make keeping memblock memory opt-in rather than opt-out

Most architectures do not need the memblock memory after the page
allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the
arch Kconfig.

Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the
logic makes it clear which architectures actually use memblock after
system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK
to the architectures that are still missing that option.

Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

11 files changed, 4 insertions, 8 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index a11dfcc2a130..5fd344bd06b9 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -4,7 +4,6 @@ config ARM
         default y
         select ARCH_32BIT_OFF_T
         select ARCH_CLOCKSOURCE_DATA
-        select ARCH_DISCARD_MEMBLOCK if !HAVE_ARCH_PFN_VALID && !KEXEC
         select ARCH_HAS_DEBUG_VIRTUAL if MMU
         select ARCH_HAS_DEVMEM_IS_ALLOWED
         select ARCH_HAS_ELF_RANDOMIZE
@@ -22,6 +21,7 @@ config ARM
         select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
         select ARCH_HAVE_CUSTOM_GPIO_H
         select ARCH_HAS_GCOV_PROFILE_ALL
+        select ARCH_KEEP_MEMBLOCK if HAVE_ARCH_PFN_VALID || KEXEC
         select ARCH_MIGHT_HAVE_PC_PARPORT
         select ARCH_NO_SG_CHAIN if !ARM_HAS_SG_CHAIN
         select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 7a1aa53d188d..69a59a5d1143 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -60,6 +60,7 @@ config ARM64
         select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPT
         select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPT
         select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPT
+        select ARCH_KEEP_MEMBLOCK
         select ARCH_USE_CMPXCHG_LOCKREF
         select ARCH_USE_QUEUED_RWLOCKS
         select ARCH_USE_QUEUED_SPINLOCKS
diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
index 3e54a53208d5..b7d404bbaa0f 100644
--- a/arch/hexagon/Kconfig
+++ b/arch/hexagon/Kconfig
@@ -22,7 +22,6 @@ config HEXAGON
         select GENERIC_IRQ_SHOW
         select HAVE_ARCH_KGDB
         select HAVE_ARCH_TRACEHOOK
-        select ARCH_DISCARD_MEMBLOCK
         select NEED_SG_DMA_LENGTH
         select NO_IOPORT_MAP
         select GENERIC_IOMAP
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 73a26f04644e..7468d8e50467 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -33,7 +33,6 @@ config IA64
         select ARCH_HAS_DMA_COHERENT_TO_PFN if SWIOTLB
         select ARCH_HAS_SYNC_DMA_FOR_CPU if SWIOTLB
         select VIRT_TO_BUS
-        select ARCH_DISCARD_MEMBLOCK
         select GENERIC_IRQ_PROBE
         select GENERIC_PENDING_IRQ if SMP
         select GENERIC_IRQ_SHOW
diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index fe5cc2da6d10..218e037ef901 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -26,7 +26,6 @@ config M68K
         select MODULES_USE_ELF_RELA
         select OLD_SIGSUSPEND3
         select OLD_SIGACTION
-        select ARCH_DISCARD_MEMBLOCK
         select MMU_GATHER_NO_RANGE if MMU
 
 config CPU_BIG_ENDIAN
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index ff8cff9fcf54..677e5bfeff47 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -5,7 +5,6 @@ config MIPS
         select ARCH_32BIT_OFF_T if !64BIT
         select ARCH_BINFMT_ELF_STATE if MIPS_FP_SUPPORT
         select ARCH_CLOCKSOURCE_DATA
-        select ARCH_DISCARD_MEMBLOCK
         select ARCH_HAS_ELF_RANDOMIZE
         select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
         select ARCH_HAS_UBSAN_SANITIZE_ALL
diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
index ea37394ff3ea..26a9c760a98b 100644
--- a/arch/nios2/Kconfig
+++ b/arch/nios2/Kconfig
@@ -23,7 +23,6 @@ config NIOS2
         select SPARSE_IRQ
         select USB_ARCH_HAS_HCD if USB_SUPPORT
         select CPU_NO_EFFICIENT_FFS
-        select ARCH_DISCARD_MEMBLOCK
         select MMU_GATHER_NO_RANGE if MMU
 
 config GENERIC_CSUM
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index d7996cfaceca..8c1c636308c8 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -137,6 +137,7 @@ config PPC
         select ARCH_HAS_UBSAN_SANITIZE_ALL
         select ARCH_HAS_ZONE_DEVICE             if PPC_BOOK3S_64
         select ARCH_HAVE_NMI_SAFE_CMPXCHG
+        select ARCH_KEEP_MEMBLOCK
         select ARCH_MIGHT_HAVE_PC_PARPORT
         select ARCH_MIGHT_HAVE_PC_SERIO
         select ARCH_OPTIONAL_KERNEL_RWX         if ARCH_HAS_STRICT_KERNEL_RWX
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index d0c046af65fa..109243fdb6ec 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -100,6 +100,7 @@ config S390
         select ARCH_INLINE_WRITE_UNLOCK_BH
         select ARCH_INLINE_WRITE_UNLOCK_IRQ
         select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
+        select ARCH_KEEP_MEMBLOCK
         select ARCH_SAVE_PAGE_KEYS if HIBERNATION
         select ARCH_SUPPORTS_ATOMIC_RMW
         select ARCH_SUPPORTS_NUMA_BALANCING
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 2a77033e1e7c..b77f512bb176 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -10,7 +10,6 @@ config SUPERH
         select DMA_DECLARE_COHERENT
         select HAVE_IDE if HAS_IOPORT_MAP
         select HAVE_MEMBLOCK_NODE_MAP
-        select ARCH_DISCARD_MEMBLOCK
         select HAVE_OPROFILE
         select HAVE_ARCH_TRACEHOOK
         select HAVE_PERF_EVENTS
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f21bc56e5d7b..818b361094ed 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -47,7 +47,6 @@ config X86
         select ARCH_32BIT_OFF_T                 if X86_32
         select ARCH_CLOCKSOURCE_DATA
         select ARCH_CLOCKSOURCE_INIT
-        select ARCH_DISCARD_MEMBLOCK
         select ARCH_HAS_ACPI_TABLE_UPGRADE      if ACPI
         select ARCH_HAS_DEBUG_VIRTUAL
         select ARCH_HAS_DEVMEM_IS_ALLOWED