The amount of DMA mappings from Hisilicon HNS ethernet devices is huge,
so it could trigger "DMA-API: debugging out of memory - disabling".
hnae_get_handle [1]
hnae_init_queue
hnae_init_ring
hnae_alloc_buffers [2]
debug_dma_map_page
dma_entry_alloc
[1] for (i = 0; i < handle->q_num; i++)
[2] for (i = 0; i < ring->desc_num; i++)
Also, "#define HNS_DSAF_MAX_DESC_CNT 1024"
On this Huawei TaiShan 2280 aarch64 server, it has reached the limit
already,
4 (NICs) x 16 (queues) x 1024 (port descption numbers) = 65536
Added a Kconfig entry for PREALLOC_DMA_DEBUG_ENTRIES, so make it easier
for users to deal with special cases like this.
Signed-off-by: Qian Cai <c...@gmx.us>
---
Changes since v1:
* Increased the default value if has HNS_ENET suggested by Robin.
kernel/dma/debug.c | 9 ++-------
lib/Kconfig.debug | 10 ++++++++++
2 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 231ca4628062..3752fb23f72f 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -41,11 +41,6 @@
#define HASH_FN_SHIFT 13
#define HASH_FN_MASK (HASH_SIZE - 1)
-/* allow architectures to override this if absolutely required */
-#ifndef PREALLOC_DMA_DEBUG_ENTRIES
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-#endif
-
enum {
dma_debug_single,
dma_debug_page,
@@ -132,7 +127,7 @@ static u32 min_free_entries;
static u32 nr_total_entries;
/* number of preallocated entries requested by kernel cmdline */
-static u32 nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES;
+static u32 nr_prealloc_entries = CONFIG_PREALLOC_DMA_DEBUG_ENTRIES;
/* debugfs dentry's for the stuff above */
static struct dentry *dma_debug_dent __read_mostly;
@@ -1063,7 +1058,7 @@ static __init int dma_debug_entries_cmdline(char *str)
if (!str)
return -EINVAL;
if (!get_option(&str, &nr_prealloc_entries))
- nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES;
+ nr_prealloc_entries = CONFIG_PREALLOC_DMA_DEBUG_ENTRIES;
return 0;
}
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 1af29b8224fd..9f85a7a13647 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1659,6 +1659,16 @@ config DMA_API_DEBUG
If unsure, say N.
+config PREALLOC_DMA_DEBUG_ENTRIES
+ int "Preallocated DMA-API debugging entries"
+ depends on DMA_API_DEBUG
+ default 131072 if HNS_ENET
+ default 65536
+ help
+ The number of preallocated entries for DMA-API debugging code. One
+ entry is required per DMA-API allocation. Increase this if the DMA-API
+ debugging code disables itself because the default is too low.
+
config DMA_API_DEBUG_SG
bool "Debug DMA scatter-gather usage"
default y
--
2.17.2 (Apple Git-113)
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