diff options
| -rw-r--r-- | include/linux/swiotlb.h | 3 | ||||
| -rw-r--r-- | kernel/dma/swiotlb.c | 46 |
2 files changed, 49 insertions, 0 deletions
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index ecde0312dd52..ea23097e351f 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -120,6 +120,8 @@ struct io_tlb_pool { * debugfs. * @used_hiwater: The high water mark for total_used. Used only for reporting * in debugfs. + * @transient_nslabs: The total number of slots in all transient pools that + * are currently used across all areas. */ struct io_tlb_mem { struct io_tlb_pool defpool; @@ -137,6 +139,7 @@ struct io_tlb_mem { #ifdef CONFIG_DEBUG_FS atomic_long_t total_used; atomic_long_t used_hiwater; + atomic_long_t transient_nslabs; #endif }; diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index b079a9a8e087..77974cea3e69 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -956,6 +956,28 @@ static void dec_used(struct io_tlb_mem *mem, unsigned int nslots) } #endif /* CONFIG_DEBUG_FS */ +#ifdef CONFIG_SWIOTLB_DYNAMIC +#ifdef CONFIG_DEBUG_FS +static void inc_transient_used(struct io_tlb_mem *mem, unsigned int nslots) +{ + atomic_long_add(nslots, &mem->transient_nslabs); +} + +static void dec_transient_used(struct io_tlb_mem *mem, unsigned int nslots) +{ + atomic_long_sub(nslots, &mem->transient_nslabs); +} + +#else /* !CONFIG_DEBUG_FS */ +static void inc_transient_used(struct io_tlb_mem *mem, unsigned int nslots) +{ +} +static void dec_transient_used(struct io_tlb_mem *mem, unsigned int nslots) +{ +} +#endif /* CONFIG_DEBUG_FS */ +#endif /* CONFIG_SWIOTLB_DYNAMIC */ + /** * swiotlb_search_pool_area() - search one memory area in one pool * @dev: Device which maps the buffer. @@ -1170,6 +1192,7 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr, spin_lock_irqsave(&dev->dma_io_tlb_lock, flags); list_add_rcu(&pool->node, &dev->dma_io_tlb_pools); spin_unlock_irqrestore(&dev->dma_io_tlb_lock, flags); + inc_transient_used(mem, pool->nslabs); found: WRITE_ONCE(dev->dma_uses_io_tlb, true); @@ -1415,6 +1438,7 @@ static bool swiotlb_del_transient(struct device *dev, phys_addr_t tlb_addr) dec_used(dev->dma_io_tlb_mem, pool->nslabs); swiotlb_del_pool(dev, pool); + dec_transient_used(dev->dma_io_tlb_mem, pool->nslabs); return true; } @@ -1557,6 +1581,23 @@ phys_addr_t default_swiotlb_limit(void) } #ifdef CONFIG_DEBUG_FS +#ifdef CONFIG_SWIOTLB_DYNAMIC +static unsigned long mem_transient_used(struct io_tlb_mem *mem) +{ + return atomic_long_read(&mem->transient_nslabs); +} + +static int io_tlb_transient_used_get(void *data, u64 *val) +{ + struct io_tlb_mem *mem = data; + + *val = mem_transient_used(mem); + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(fops_io_tlb_transient_used, io_tlb_transient_used_get, + NULL, "%llu\n"); +#endif /* CONFIG_SWIOTLB_DYNAMIC */ static int io_tlb_used_get(void *data, u64 *val) { @@ -1605,6 +1646,11 @@ static void swiotlb_create_debugfs_files(struct io_tlb_mem *mem, &fops_io_tlb_used); debugfs_create_file("io_tlb_used_hiwater", 0600, mem->debugfs, mem, &fops_io_tlb_hiwater); +#ifdef CONFIG_SWIOTLB_DYNAMIC + atomic_long_set(&mem->transient_nslabs, 0); + debugfs_create_file("io_tlb_transient_nslabs", 0400, mem->debugfs, + mem, &fops_io_tlb_transient_used); +#endif } static int __init swiotlb_create_default_debugfs(void) |