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>

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index a11dfcc..5fd344b 100644 (file)
--- 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 7a1aa53..69a59a5 100644 (file)
--- 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 3e54a53..b7d404b 100644 (file)
--- 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 73a26f0..7468d8e 100644 (file)
--- 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 fe5cc2d..218e037 100644 (file)
--- 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 ff8cff9..677e5bf 100644 (file)
--- 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 ea37394..26a9c76 100644 (file)
--- 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 d7996cf..8c1c636 100644 (file)
--- 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 d0c046a..109243f 100644 (file)
--- 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 2a77033..b77f512 100644 (file)
--- 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 f21bc56..818b361 100644 (file)
--- 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

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 47e3c06..676d390 100644 (file)
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -96,13 +96,14 @@ struct memblock {
 extern struct memblock memblock;
 extern int memblock_debug;
 
-#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK
+#ifndef CONFIG_ARCH_KEEP_MEMBLOCK
 #define __init_memblock __meminit
 #define __initdata_memblock __meminitdata
 void memblock_discard(void);
 #else
 #define __init_memblock
 #define __initdata_memblock
+static inline void memblock_discard(void) {}
 #endif
 
 #define memblock_dbg(fmt, ...) \

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index f7fb8f6..072b6ee 100644 (file)
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -500,13 +500,7 @@ static int locate_mem_hole_callback(struct resource *res, void *arg)
        return locate_mem_hole_bottom_up(start, end, kbuf);
 }
 
-#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK
-static int kexec_walk_memblock(struct kexec_buf *kbuf,
-                              int (*func)(struct resource *, void *))
-{
-       return 0;
-}
-#else
+#ifdef CONFIG_ARCH_KEEP_MEMBLOCK
 static int kexec_walk_memblock(struct kexec_buf *kbuf,
                               int (*func)(struct resource *, void *))
 {
@@ -550,6 +544,12 @@ static int kexec_walk_memblock(struct kexec_buf *kbuf,
 
        return ret;
 }
+#else
+static int kexec_walk_memblock(struct kexec_buf *kbuf,
+                              int (*func)(struct resource *, void *))
+{
+       return 0;
+}
 #endif
 
 /**
@@ -589,7 +589,7 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf)
        if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN)
                return 0;
 
-       if (IS_ENABLED(CONFIG_ARCH_DISCARD_MEMBLOCK))
+       if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
                ret = kexec_walk_resources(kbuf, locate_mem_hole_callback);
        else
                ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback);

diff --git a/mm/Kconfig b/mm/Kconfig
index 71e697e..c5124c2 100644 (file)
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -136,7 +136,7 @@ config HAVE_MEMBLOCK_PHYS_MAP
 config HAVE_GENERIC_GUP
        bool
 
-config ARCH_DISCARD_MEMBLOCK
+config ARCH_KEEP_MEMBLOCK
        bool
 
 config MEMORY_ISOLATION

diff --git a/mm/memblock.c b/mm/memblock.c
index f315eca..6bbad46 100644 (file)
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -94,7 +94,7 @@
  * :c:func:`mem_init` function frees all the memory to the buddy page
  * allocator.
  *
- * If an architecure enables %CONFIG_ARCH_DISCARD_MEMBLOCK, the
+ * Unless an architecure enables %CONFIG_ARCH_KEEP_MEMBLOCK, the
  * memblock data structures will be discarded after the system
  * initialization compltes.
  */
@@ -375,7 +375,7 @@ static void __init_memblock memblock_remove_region(struct memblock_type *type, u
        }
 }
 
-#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK
+#ifndef CONFIG_ARCH_KEEP_MEMBLOCK
 /**
  * memblock_discard - discard memory and reserved arrays if they were allocated
  */
@@ -1987,7 +1987,7 @@ unsigned long __init memblock_free_all(void)
        return pages;
 }
 
-#if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
+#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_ARCH_KEEP_MEMBLOCK)
 
 static int memblock_debug_show(struct seq_file *m, void *private)
 {

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index cbda9ae..f2f3fb4 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1896,10 +1896,9 @@ void __init page_alloc_init_late(void)
        /* Reinit limits that are based on free pages after the kernel is up */
        files_maxfiles_init();
 #endif
-#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK
+
        /* Discard memblock private memory */
        memblock_discard();
-#endif
 
        for_each_populated_zone(zone)
                set_zone_contiguous(zone);