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ARM: cache-l2x0: avoid taking spinlock for every iteration

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Taking the spinlock for every iteration is very expensive; instead,
batch iterations up into 4K blocks, releasing and reacquiring the
spinlock between each block.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Russell King 2009-11-19 11:12:15 +00:00
parent 22763c5cf3
commit 0eb948dd7f
1 changed files with 52 additions and 13 deletions
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65
arch/arm/mm/cache-l2x0.c
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@ -31,14 +31,10 @@ static DEFINE_SPINLOCK(l2x0_lock);
static inline void sync_writel(unsigned long val, unsigned long reg,
unsigned long complete_mask)
{
unsigned long flags;
spin_lock_irqsave(&l2x0_lock, flags);
writel(val, l2x0_base + reg);
/* wait for the operation to complete */
while (readl(l2x0_base + reg) & complete_mask)
;
spin_unlock_irqrestore(&l2x0_lock, flags);
}
static inline void cache_sync(void)
@ -48,15 +44,20 @@ static inline void cache_sync(void)
static inline void l2x0_inv_all(void)
{
unsigned long flags;
/* invalidate all ways */
spin_lock_irqsave(&l2x0_lock, flags);
sync_writel(0xff, L2X0_INV_WAY, 0xff);
cache_sync();
spin_unlock_irqrestore(&l2x0_lock, flags);
}
static void l2x0_inv_range(unsigned long start, unsigned long end)
{
unsigned long addr;
unsigned long flags;
spin_lock_irqsave(&l2x0_lock, flags);
if (start & (CACHE_LINE_SIZE - 1)) {
start &= ~(CACHE_LINE_SIZE - 1);
sync_writel(start, L2X0_CLEAN_INV_LINE_PA, 1);
@ -68,29 +69,67 @@ static void l2x0_inv_range(unsigned long start, unsigned long end)
sync_writel(end, L2X0_CLEAN_INV_LINE_PA, 1);
}
for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
sync_writel(addr, L2X0_INV_LINE_PA, 1);
while (start < end) {
unsigned long blk_end = start + min(end - start, 4096UL);
while (start < blk_end) {
sync_writel(start, L2X0_INV_LINE_PA, 1);
start += CACHE_LINE_SIZE;
}
if (blk_end < end) {
spin_unlock_irqrestore(&l2x0_lock, flags);
spin_lock_irqsave(&l2x0_lock, flags);
}
}
cache_sync();
spin_unlock_irqrestore(&l2x0_lock, flags);
}
static void l2x0_clean_range(unsigned long start, unsigned long end)
{
unsigned long addr;
unsigned long flags;
spin_lock_irqsave(&l2x0_lock, flags);
start &= ~(CACHE_LINE_SIZE - 1);
for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
sync_writel(addr, L2X0_CLEAN_LINE_PA, 1);
while (start < end) {
unsigned long blk_end = start + min(end - start, 4096UL);
while (start < blk_end) {
sync_writel(start, L2X0_CLEAN_LINE_PA, 1);
start += CACHE_LINE_SIZE;
}
if (blk_end < end) {
spin_unlock_irqrestore(&l2x0_lock, flags);
spin_lock_irqsave(&l2x0_lock, flags);
}
}
cache_sync();
spin_unlock_irqrestore(&l2x0_lock, flags);
}
static void l2x0_flush_range(unsigned long start, unsigned long end)
{
unsigned long addr;
unsigned long flags;
spin_lock_irqsave(&l2x0_lock, flags);
start &= ~(CACHE_LINE_SIZE - 1);
for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
sync_writel(addr, L2X0_CLEAN_INV_LINE_PA, 1);
while (start < end) {
unsigned long blk_end = start + min(end - start, 4096UL);
while (start < blk_end) {
sync_writel(start, L2X0_CLEAN_INV_LINE_PA, 1);
start += CACHE_LINE_SIZE;
}
if (blk_end < end) {
spin_unlock_irqrestore(&l2x0_lock, flags);
spin_lock_irqsave(&l2x0_lock, flags);
}
}
cache_sync();
spin_unlock_irqrestore(&l2x0_lock, flags);
}
void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask)