[PATCH 0/2] sparc32: switch to NO_BOOTMEM

[PATCH 0/2] sparc32: switch to NO_BOOTMEM

[Mike Rapoport]

Hi,

These patches convert sparc32 to use memblock + nobootmem.
I've made the conversion as simple as possible, just enough to allow moving
HAVE_MEMBLOCK and NO_BOOTMEM to the common SPARC configuration.

Mike Rapoport (2):
  sparc32: switch to NO_BOOTMEM
  sparc32: tidy up ramdisk memory reservation

 arch/sparc/Kconfig      |  4 +--
 arch/sparc/mm/init_32.c | 90 +++++++++++++++----------------------------------
 2 files changed, 29 insertions(+), 65 deletions(-)

-- 
2.7.4

[PATCH 1/2] sparc32: switch to NO_BOOTMEM

[Mike Rapoport]

Each populated sparc_phys_bank is added to memblock.memory. The
reserve_bootmem() calls are replaced with memblock_reserve(), and the
bootmem bitmap initialization is droppped.

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
 arch/sparc/Kconfig      |  4 +--
 arch/sparc/mm/init_32.c | 74 ++++++++++++++-----------------------------------
 2 files changed, 23 insertions(+), 55 deletions(-)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 0f535de..0a874c8 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -45,6 +45,8 @@ config SPARC
 	select LOCKDEP_SMALL if LOCKDEP
 	select NEED_DMA_MAP_STATE
 	select NEED_SG_DMA_LENGTH
+	select HAVE_MEMBLOCK
+	select NO_BOOTMEM
 
 config SPARC32
 	def_bool !64BIT
@@ -60,7 +62,6 @@ config SPARC64
 	select HAVE_KRETPROBES
 	select HAVE_KPROBES
 	select HAVE_RCU_TABLE_FREE if SMP
-	select HAVE_MEMBLOCK
 	select HAVE_MEMBLOCK_NODE_MAP
 	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
 	select HAVE_DYNAMIC_FTRACE
@@ -79,7 +80,6 @@ config SPARC64
 	select IRQ_PREFLOW_FASTEOI
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG
 	select HAVE_C_RECORDMCOUNT
-	select NO_BOOTMEM
 	select HAVE_ARCH_AUDITSYSCALL
 	select ARCH_SUPPORTS_ATOMIC_RMW
 	select HAVE_NMI
diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index 95fe4f0..5117a5e 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -23,6 +23,7 @@
 #include <linux/init.h>
 #include <linux/highmem.h>
 #include <linux/bootmem.h>
+#include <linux/memblock.h>
 #include <linux/pagemap.h>
 #include <linux/poison.h>
 #include <linux/gfp.h>
@@ -103,11 +104,15 @@ static unsigned long calc_max_low_pfn(void)
 
 unsigned long __init bootmem_init(unsigned long *pages_avail)
 {
-	unsigned long bootmap_size, start_pfn;
+	unsigned long start_pfn;
 	unsigned long end_of_phys_memory = 0UL;
-	unsigned long bootmap_pfn, bytes_avail, size;
+	unsigned long bytes_avail, size;
+	unsigned long high_pages = 0UL;
 	int i;
 
+	memblock_set_bottom_up(true);
+	memblock_allow_resize();
+
 	bytes_avail = 0UL;
 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 		end_of_phys_memory = sp_banks[i].base_addr +
@@ -124,12 +129,15 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 				if (sp_banks[i].num_bytes == 0) {
 					sp_banks[i].base_addr = 0xdeadbeef;
 				} else {
+					memblock_add(sp_banks[i].base_addr,
+						     sp_banks[i].num_bytes);
 					sp_banks[i+1].num_bytes = 0;
 					sp_banks[i+1].base_addr = 0xdeadbeef;
 				}
 				break;
 			}
 		}
+		memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
 	}
 
 	/* Start with page aligned address of last symbol in kernel
@@ -140,8 +148,6 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 	/* Now shift down to get the real physical page frame number. */
 	start_pfn >>= PAGE_SHIFT;
 
-	bootmap_pfn = start_pfn;
-
 	max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 
 	max_low_pfn = max_pfn;
@@ -150,12 +156,16 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 	if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 		highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 		max_low_pfn = calc_max_low_pfn();
+		high_pages = calc_highpages();
 		printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
-		    calc_highpages() >> (20 - PAGE_SHIFT));
+		    high_pages >> (20 - PAGE_SHIFT));
 	}
 
 #ifdef CONFIG_BLK_DEV_INITRD
-	/* Now have to check initial ramdisk, so that bootmap does not overwrite it */
+	/*
+	 * Now have to check initial ramdisk, so that it won't pass
+	 * the end of memory
+	 */
 	if (sparc_ramdisk_image) {
 		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 			sparc_ramdisk_image -= KERNBASE;
@@ -167,67 +177,25 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 			       initrd_end, end_of_phys_memory);
 			initrd_start = 0;
 		}
-		if (initrd_start) {
-			if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
-			    initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
-				bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
-		}
 	}
-#endif	
-	/* Initialize the boot-time allocator. */
-	bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
-					 max_low_pfn);
-
-	/* Now register the available physical memory with the
-	 * allocator.
-	 */
-	*pages_avail = 0;
-	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
-		unsigned long curr_pfn, last_pfn;
-
-		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
-		if (curr_pfn >= max_low_pfn)
-			break;
-
-		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
-		if (last_pfn > max_low_pfn)
-			last_pfn = max_low_pfn;
-
-		/*
-		 * .. finally, did all the rounding and playing
-		 * around just make the area go away?
-		 */
-		if (last_pfn <= curr_pfn)
-			continue;
+#endif
 
-		size = (last_pfn - curr_pfn) << PAGE_SHIFT;
-		*pages_avail += last_pfn - curr_pfn;
-
-		free_bootmem(sp_banks[i].base_addr, size);
-	}
+	*pages_avail = (memblock_phys_mem_size() >> PAGE_SHIFT) - high_pages;
 
 #ifdef CONFIG_BLK_DEV_INITRD
 	if (initrd_start) {
 		/* Reserve the initrd image area. */
 		size = initrd_end - initrd_start;
-		reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
+		memblock_reserve(initrd_start, size);
 		*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 
 		initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
-		initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;		
+		initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
 	}
 #endif
 	/* Reserve the kernel text/data/bss. */
 	size = (start_pfn << PAGE_SHIFT) - phys_base;
-	reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
-	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
-
-	/* Reserve the bootmem map.   We do not account for it
-	 * in pages_avail because we will release that memory
-	 * in free_all_bootmem.
-	 */
-	size = bootmap_size;
-	reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
+	memblock_reserve(phys_base, size);
 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 
 	return max_pfn;
-- 
2.7.4

[PATCH 2/2] sparc32: tidy up ramdisk memory reservation

[Mike Rapoport]

The detection and reservation of ramdisk memory were separated to allow
bootmem bitmap initialization after the ramdisk boundaries are detected.
Since the bootmem initialization is removed, the reservation of ramdisk
memory can be done immediately after its boundaries are found.

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
 arch/sparc/mm/init_32.c | 24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index 5117a5e..b5d8f90 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -161,6 +161,8 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 		    high_pages >> (20 - PAGE_SHIFT));
 	}
 
+	*pages_avail = (memblock_phys_mem_size() >> PAGE_SHIFT) - high_pages;
+
 #ifdef CONFIG_BLK_DEV_INITRD
 	/*
 	 * Now have to check initial ramdisk, so that it won't pass
@@ -176,23 +178,17 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 		                 	 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 			       initrd_end, end_of_phys_memory);
 			initrd_start = 0;
+		} else {
+			/* Reserve the initrd image area. */
+			size = initrd_end - initrd_start;
+			memblock_reserve(initrd_start, size);
+			*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+			initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
+			initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
 		}
 	}
 #endif
-
-	*pages_avail = (memblock_phys_mem_size() >> PAGE_SHIFT) - high_pages;
-
-#ifdef CONFIG_BLK_DEV_INITRD
-	if (initrd_start) {
-		/* Reserve the initrd image area. */
-		size = initrd_end - initrd_start;
-		memblock_reserve(initrd_start, size);
-		*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
-
-		initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
-		initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
-	}
-#endif
 	/* Reserve the kernel text/data/bss. */
 	size = (start_pfn << PAGE_SHIFT) - phys_base;
 	memblock_reserve(phys_base, size);
-- 
2.7.4

Re: [PATCH 2/2] sparc32: tidy up ramdisk memory reservation

[Sam Ravnborg]

Hi Mike.

On Thu, Aug 02, 2018 at 02:53:53PM +0300, Mike Rapoport wrote:
> The detection and reservation of ramdisk memory were separated to allow
> bootmem bitmap initialization after the ramdisk boundaries are detected.
> Since the bootmem initialization is removed, the reservation of ramdisk
> memory can be done immediately after its boundaries are found.

When touching this area could you look
at introducing a find_ramdisk() function like
we do for sparc64?
It is always nice when the codebases look alike.
Then you could combine your simplification
with some refactoring that further increases
readability.

See:
https://patchwork.ozlabs.org/patch/151194/
for my attempt from long time ago.

	Sam