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[SPARC64]: Use SLAB caches for TSB tables.
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Signed-off-by: David S. Miller <davem@davemloft.net>
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David S. Miller committed Mar 20, 2006
1 parent b52439c commit 9b4006d
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Showing 3 changed files with 69 additions and 25 deletions.
3 changes: 3 additions & 0 deletions arch/sparc64/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -192,6 +192,9 @@ config ARCH_SPARSEMEM_ENABLE
config ARCH_SPARSEMEM_DEFAULT
def_bool y

config LARGE_ALLOCS
def_bool y

source "mm/Kconfig"

config GENERIC_ISA_DMA
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5 changes: 4 additions & 1 deletion arch/sparc64/mm/init.c
Original file line number Diff line number Diff line change
Expand Up @@ -165,6 +165,8 @@ static void zero_ctor(void *addr, kmem_cache_t *cache, unsigned long flags)
clear_page(addr);
}

extern void tsb_cache_init(void);

void pgtable_cache_init(void)
{
pgtable_cache = kmem_cache_create("pgtable_cache",
Expand All @@ -174,9 +176,10 @@ void pgtable_cache_init(void)
zero_ctor,
NULL);
if (!pgtable_cache) {
prom_printf("pgtable_cache_init(): Could not create!\n");
prom_printf("Could not create pgtable_cache\n");
prom_halt();
}
tsb_cache_init();
}

#ifdef CONFIG_DEBUG_DCFLUSH
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86 changes: 62 additions & 24 deletions arch/sparc64/mm/tsb.c
Original file line number Diff line number Diff line change
Expand Up @@ -11,6 +11,7 @@
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#include <asm/tsb.h>
#include <asm/oplib.h>

extern struct tsb swapper_tsb[KERNEL_TSB_NENTRIES];

Expand Down Expand Up @@ -207,6 +208,39 @@ static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_bytes)
}
}

static kmem_cache_t *tsb_caches[8] __read_mostly;

static const char *tsb_cache_names[8] = {
"tsb_8KB",
"tsb_16KB",
"tsb_32KB",
"tsb_64KB",
"tsb_128KB",
"tsb_256KB",
"tsb_512KB",
"tsb_1MB",
};

void __init tsb_cache_init(void)
{
unsigned long i;

for (i = 0; i < 8; i++) {
unsigned long size = 8192 << i;
const char *name = tsb_cache_names[i];

tsb_caches[i] = kmem_cache_create(name,
size, size,
SLAB_HWCACHE_ALIGN |
SLAB_MUST_HWCACHE_ALIGN,
NULL, NULL);
if (!tsb_caches[i]) {
prom_printf("Could not create %s cache\n", name);
prom_halt();
}
}
}

/* When the RSS of an address space exceeds mm->context.tsb_rss_limit,
* do_sparc64_fault() invokes this routine to try and grow the TSB.
*
Expand All @@ -226,45 +260,48 @@ static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_bytes)
void tsb_grow(struct mm_struct *mm, unsigned long rss)
{
unsigned long max_tsb_size = 1 * 1024 * 1024;
unsigned long size, old_size, flags;
struct page *page;
unsigned long new_size, old_size, flags;
struct tsb *old_tsb, *new_tsb;
unsigned long order, new_rss_limit;
unsigned long new_cache_index, old_cache_index;
unsigned long new_rss_limit;
gfp_t gfp_flags;

if (max_tsb_size > (PAGE_SIZE << MAX_ORDER))
max_tsb_size = (PAGE_SIZE << MAX_ORDER);

for (size = PAGE_SIZE; size < max_tsb_size; size <<= 1UL) {
unsigned long n_entries = size / sizeof(struct tsb);
new_cache_index = 0;
for (new_size = 8192; new_size < max_tsb_size; new_size <<= 1UL) {
unsigned long n_entries = new_size / sizeof(struct tsb);

n_entries = (n_entries * 3) / 4;
if (n_entries > rss)
break;

new_cache_index++;
}

if (size == max_tsb_size)
if (new_size == max_tsb_size)
new_rss_limit = ~0UL;
else
new_rss_limit = ((size / sizeof(struct tsb)) * 3) / 4;
new_rss_limit = ((new_size / sizeof(struct tsb)) * 3) / 4;

retry_page_alloc:
order = get_order(size);
retry_tsb_alloc:
gfp_flags = GFP_KERNEL;
if (order > 1)
if (new_size > (PAGE_SIZE * 2))
gfp_flags = __GFP_NOWARN | __GFP_NORETRY;

page = alloc_pages(gfp_flags, order);
if (unlikely(!page)) {
new_tsb = kmem_cache_alloc(tsb_caches[new_cache_index], gfp_flags);
if (unlikely(!new_tsb)) {
/* Not being able to fork due to a high-order TSB
* allocation failure is very bad behavior. Just back
* down to a 0-order allocation and force no TSB
* growing for this address space.
*/
if (mm->context.tsb == NULL && order > 0) {
size = PAGE_SIZE;
if (mm->context.tsb == NULL && new_cache_index > 0) {
new_cache_index = 0;
new_size = 8192;
new_rss_limit = ~0UL;
goto retry_page_alloc;
goto retry_tsb_alloc;
}

/* If we failed on a TSB grow, we are under serious
Expand All @@ -276,8 +313,7 @@ void tsb_grow(struct mm_struct *mm, unsigned long rss)
}

/* Mark all tags as invalid. */
new_tsb = page_address(page);
memset(new_tsb, 0x40, size);
memset(new_tsb, 0x40, new_size);

/* Ok, we are about to commit the changes. If we are
* growing an existing TSB the locking is very tricky,
Expand All @@ -304,16 +340,18 @@ void tsb_grow(struct mm_struct *mm, unsigned long rss)
spin_lock_irqsave(&mm->context.lock, flags);

old_tsb = mm->context.tsb;
old_cache_index = (mm->context.tsb_reg_val & 0x7UL);
old_size = mm->context.tsb_nentries * sizeof(struct tsb);


/* Handle multiple threads trying to grow the TSB at the same time.
* One will get in here first, and bump the size and the RSS limit.
* The others will get in here next and hit this check.
*/
if (unlikely(old_tsb && (rss < mm->context.tsb_rss_limit))) {
spin_unlock_irqrestore(&mm->context.lock, flags);

free_pages((unsigned long) new_tsb, get_order(size));
kmem_cache_free(tsb_caches[new_cache_index], new_tsb);
return;
}

Expand All @@ -331,11 +369,11 @@ void tsb_grow(struct mm_struct *mm, unsigned long rss)
old_tsb_base = __pa(old_tsb_base);
new_tsb_base = __pa(new_tsb_base);
}
copy_tsb(old_tsb_base, old_size, new_tsb_base, size);
copy_tsb(old_tsb_base, old_size, new_tsb_base, new_size);
}

mm->context.tsb = new_tsb;
setup_tsb_params(mm, size);
setup_tsb_params(mm, new_size);

spin_unlock_irqrestore(&mm->context.lock, flags);

Expand All @@ -350,7 +388,7 @@ void tsb_grow(struct mm_struct *mm, unsigned long rss)
smp_tsb_sync(mm);

/* Now it is safe to free the old tsb. */
free_pages((unsigned long) old_tsb, get_order(old_size));
kmem_cache_free(tsb_caches[old_cache_index], old_tsb);
}
}

Expand Down Expand Up @@ -379,10 +417,10 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm)

void destroy_context(struct mm_struct *mm)
{
unsigned long size = mm->context.tsb_nentries * sizeof(struct tsb);
unsigned long flags;
unsigned long flags, cache_index;

free_pages((unsigned long) mm->context.tsb, get_order(size));
cache_index = (mm->context.tsb_reg_val & 0x7UL);
kmem_cache_free(tsb_caches[cache_index], mm->context.tsb);

/* We can remove these later, but for now it's useful
* to catch any bogus post-destroy_context() references
Expand Down

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