memblock: Introduce default allocation limit and use it to replace explicit ones

This introduce memblock.current_limit which is used to limit allocations
from memblock_alloc() or memblock_alloc_base(..., MEMBLOCK_ALLOC_ACCESSIBLE).

The old MEMBLOCK_ALLOC_ANYWHERE changes value from 0 to ~(u64)0 and can still
be used with memblock_alloc_base() to allocate really anywhere.

It is -no-longer- cropped to MEMBLOCK_REAL_LIMIT which disappears.

Note to archs: I'm leaving the default limit to MEMBLOCK_ALLOC_ANYWHERE. I
strongly recommend that you ensure that you set an appropriate limit
during boot in order to guarantee that an memblock_alloc() at any time
results in something that is accessible with a simple __va().

The reason is that a subsequent patch will introduce the ability for
the array to resize itself by reallocating itself. The MEMBLOCK core will
honor the current limit when performing those allocations.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt 2010-07-06 15:39:01 -07:00
parent 27f574c223
commit e63075a3c9
14 changed files with 63 additions and 53 deletions

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@ -9,9 +9,6 @@
#ifndef _ASM_MICROBLAZE_MEMBLOCK_H
#define _ASM_MICROBLAZE_MEMBLOCK_H
/* MEMBLOCK limit is OFF */
#define MEMBLOCK_REAL_LIMIT 0xFFFFFFFF
#endif /* _ASM_MICROBLAZE_MEMBLOCK_H */

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@ -5,11 +5,4 @@
#define MEMBLOCK_DBG(fmt...) udbg_printf(fmt)
#ifdef CONFIG_PPC32
extern phys_addr_t lowmem_end_addr;
#define MEMBLOCK_REAL_LIMIT lowmem_end_addr
#else
#define MEMBLOCK_REAL_LIMIT 0
#endif
#endif /* _ASM_POWERPC_MEMBLOCK_H */

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@ -98,7 +98,7 @@ static void __init move_device_tree(void)
if ((memory_limit && (start + size) > memory_limit) ||
overlaps_crashkernel(start, size)) {
p = __va(memblock_alloc_base(size, PAGE_SIZE, memblock.rmo_size));
p = __va(memblock_alloc(size, PAGE_SIZE));
memcpy(p, initial_boot_params, size);
initial_boot_params = (struct boot_param_header *)p;
DBG("Moved device tree to 0x%p\n", p);
@ -655,6 +655,21 @@ static void __init phyp_dump_reserve_mem(void)
static inline void __init phyp_dump_reserve_mem(void) {}
#endif /* CONFIG_PHYP_DUMP && CONFIG_PPC_RTAS */
static void set_boot_memory_limit(void)
{
#ifdef CONFIG_PPC32
/* 601 can only access 16MB at the moment */
if (PVR_VER(mfspr(SPRN_PVR)) == 1)
memblock_set_current_limit(0x01000000);
/* 8xx can only access 8MB at the moment */
else if (PVR_VER(mfspr(SPRN_PVR)) == 0x50)
memblock_set_current_limit(0x00800000);
else
memblock_set_current_limit(0x10000000);
#else
memblock_set_current_limit(memblock.rmo_size);
#endif
}
void __init early_init_devtree(void *params)
{
@ -683,6 +698,7 @@ void __init early_init_devtree(void *params)
/* Scan memory nodes and rebuild MEMBLOCKs */
memblock_init();
of_scan_flat_dt(early_init_dt_scan_root, NULL);
of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
@ -718,6 +734,8 @@ void __init early_init_devtree(void *params)
DBG("Phys. mem: %llx\n", memblock_phys_mem_size());
set_boot_memory_limit();
/* We may need to relocate the flat tree, do it now.
* FIXME .. and the initrd too? */
move_device_tree();

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@ -246,7 +246,7 @@ static void __init irqstack_early_init(void)
unsigned int i;
/* interrupt stacks must be in lowmem, we get that for free on ppc32
* as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
* as the memblock is limited to lowmem by default */
for_each_possible_cpu(i) {
softirq_ctx[i] = (struct thread_info *)
__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));

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@ -35,6 +35,7 @@
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/highmem.h>
#include <linux/memblock.h>
#include <asm/pgalloc.h>
#include <asm/prom.h>
@ -47,6 +48,7 @@
#include <asm/bootx.h>
#include <asm/machdep.h>
#include <asm/setup.h>
#include "mmu_decl.h"
extern int __map_without_ltlbs;
@ -139,8 +141,7 @@ unsigned long __init mmu_mapin_ram(unsigned long top)
* coverage with normal-sized pages (or other reasons) do not
* attempt to allocate outside the allowed range.
*/
__initial_memory_limit_addr = memstart_addr + mapped;
memblock_set_current_limit(memstart_addr + mapped);
return mapped;
}

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@ -40,6 +40,7 @@
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/highmem.h>
#include <linux/memblock.h>
#include <asm/pgalloc.h>
#include <asm/prom.h>
@ -212,5 +213,5 @@ void __init adjust_total_lowmem(void)
pr_cont("%lu Mb, residual: %dMb\n", tlbcam_sz(tlbcam_index - 1) >> 20,
(unsigned int)((total_lowmem - __max_low_memory) >> 20));
__initial_memory_limit_addr = memstart_addr + __max_low_memory;
memblock_set_current_limit(memstart_addr + __max_low_memory);
}

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@ -696,7 +696,8 @@ static void __init htab_initialize(void)
#endif /* CONFIG_U3_DART */
BUG_ON(htab_bolt_mapping(base, base + size, __pa(base),
prot, mmu_linear_psize, mmu_kernel_ssize));
}
}
memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE);
/*
* If we have a memory_limit and we've allocated TCEs then we need to

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@ -91,12 +91,6 @@ int __allow_ioremap_reserved;
/* max amount of low RAM to map in */
unsigned long __max_low_memory = MAX_LOW_MEM;
/*
* address of the limit of what is accessible with initial MMU setup -
* 256MB usually, but only 16MB on 601.
*/
phys_addr_t __initial_memory_limit_addr = (phys_addr_t)0x10000000;
/*
* Check for command-line options that affect what MMU_init will do.
*/
@ -126,13 +120,6 @@ void __init MMU_init(void)
if (ppc_md.progress)
ppc_md.progress("MMU:enter", 0x111);
/* 601 can only access 16MB at the moment */
if (PVR_VER(mfspr(SPRN_PVR)) == 1)
__initial_memory_limit_addr = 0x01000000;
/* 8xx can only access 8MB at the moment */
if (PVR_VER(mfspr(SPRN_PVR)) == 0x50)
__initial_memory_limit_addr = 0x00800000;
/* parse args from command line */
MMU_setup();
@ -190,20 +177,18 @@ void __init MMU_init(void)
#ifdef CONFIG_BOOTX_TEXT
btext_unmap();
#endif
/* Shortly after that, the entire linear mapping will be available */
memblock_set_current_limit(lowmem_end_addr);
}
/* This is only called until mem_init is done. */
void __init *early_get_page(void)
{
void *p;
if (init_bootmem_done) {
p = alloc_bootmem_pages(PAGE_SIZE);
} else {
p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE,
__initial_memory_limit_addr));
}
return p;
if (init_bootmem_done)
return alloc_bootmem_pages(PAGE_SIZE);
else
return __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
}
/* Free up now-unused memory */

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@ -223,8 +223,7 @@ void __init MMU_init_hw(void)
* Find some memory for the hash table.
*/
if ( ppc_md.progress ) ppc_md.progress("hash:find piece", 0x322);
Hash = __va(memblock_alloc_base(Hash_size, Hash_size,
__initial_memory_limit_addr));
Hash = __va(memblock_alloc(Hash_size, Hash_size));
cacheable_memzero(Hash, Hash_size);
_SDR1 = __pa(Hash) | SDR1_LOW_BITS;

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@ -432,6 +432,8 @@ static void __early_init_mmu(int boot_cpu)
* the MMU configuration
*/
mb();
memblock_set_current_limit(linear_map_top);
}
void __init early_init_mmu(void)

View File

@ -1,6 +1,4 @@
#ifndef __ASM_SH_MEMBLOCK_H
#define __ASM_SH_MEMBLOCK_H
#define MEMBLOCK_REAL_LIMIT 0
#endif /* __ASM_SH_MEMBLOCK_H */

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@ -5,6 +5,4 @@
#define MEMBLOCK_DBG(fmt...) prom_printf(fmt)
#define MEMBLOCK_REAL_LIMIT 0
#endif /* !(_SPARC64_MEMBLOCK_H) */

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@ -34,6 +34,7 @@ struct memblock_type {
struct memblock {
unsigned long debug;
u64 rmo_size;
u64 current_limit;
struct memblock_type memory;
struct memblock_type reserved;
};
@ -46,11 +47,16 @@ extern long memblock_add(u64 base, u64 size);
extern long memblock_remove(u64 base, u64 size);
extern long __init memblock_free(u64 base, u64 size);
extern long __init memblock_reserve(u64 base, u64 size);
extern u64 __init memblock_alloc_nid(u64 size, u64 align, int nid);
extern u64 __init memblock_alloc(u64 size, u64 align);
/* Flags for memblock_alloc_base() amd __memblock_alloc_base() */
#define MEMBLOCK_ALLOC_ANYWHERE (~(u64)0)
#define MEMBLOCK_ALLOC_ACCESSIBLE 0
extern u64 __init memblock_alloc_base(u64 size,
u64, u64 max_addr);
#define MEMBLOCK_ALLOC_ANYWHERE 0
extern u64 __init __memblock_alloc_base(u64 size,
u64 align, u64 max_addr);
extern u64 __init memblock_phys_mem_size(void);
@ -66,6 +72,14 @@ extern void memblock_dump_all(void);
/* Provided by the architecture */
extern u64 memblock_nid_range(u64 start, u64 end, int *nid);
/**
* memblock_set_current_limit - Set the current allocation limit to allow
* limiting allocations to what is currently
* accessible during boot
* @limit: New limit value (physical address)
*/
extern void memblock_set_current_limit(u64 limit);
/*
* pfn conversion functions

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@ -115,6 +115,8 @@ void __init memblock_init(void)
memblock.reserved.regions[0].base = 0;
memblock.reserved.regions[0].size = 0;
memblock.reserved.cnt = 1;
memblock.current_limit = MEMBLOCK_ALLOC_ANYWHERE;
}
void __init memblock_analyze(void)
@ -373,7 +375,7 @@ u64 __init memblock_alloc_nid(u64 size, u64 align, int nid)
u64 __init memblock_alloc(u64 size, u64 align)
{
return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
}
u64 __init memblock_alloc_base(u64 size, u64 align, u64 max_addr)
@ -399,14 +401,9 @@ u64 __init __memblock_alloc_base(u64 size, u64 align, u64 max_addr)
size = memblock_align_up(size, align);
/* On some platforms, make sure we allocate lowmem */
/* Note that MEMBLOCK_REAL_LIMIT may be MEMBLOCK_ALLOC_ANYWHERE */
if (max_addr == MEMBLOCK_ALLOC_ANYWHERE)
max_addr = MEMBLOCK_REAL_LIMIT;
/* Pump up max_addr */
if (max_addr == MEMBLOCK_ALLOC_ANYWHERE)
max_addr = ~(u64)0;
if (max_addr == MEMBLOCK_ALLOC_ACCESSIBLE)
max_addr = memblock.current_limit;
/* We do a top-down search, this tends to limit memory
* fragmentation by keeping early boot allocs near the
@ -527,3 +524,9 @@ int memblock_is_region_reserved(u64 base, u64 size)
return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
}
void __init memblock_set_current_limit(u64 limit)
{
memblock.current_limit = limit;
}