Hi Christoph,
Nice cleanup! Looks good overall, just a couple of nits.
On 20/04/18 09:02, Christoph Hellwig wrote:
[...]
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 7f5cdc1e6b29..712a897174e4 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -41,6 +41,11 @@
#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,
@@ -1004,18 +1009,16 @@ void dma_debug_add_bus(struct bus_type *bus)
bus_register_notifier(bus, nb);
}
-/*
- * Let the architectures decide how many entries should be preallocated.
- */
-void dma_debug_init(u32 num_entries)
+static int dma_debug_init(void)
{
+ u32 num_entries;
Maybe initialise it to PREALLOC_DMA_DEBUG_ENTRIES?
int i;
/* Do not use dma_debug_initialized here, since we really want to be
* called to set dma_debug_initialized
*/
if (global_disable)
- return;
+ return 0;
for (i = 0; i < HASH_SIZE; ++i) {
INIT_LIST_HEAD(&dma_entry_hash[i].list);
@@ -1026,17 +1029,19 @@ void dma_debug_init(u32 num_entries)
pr_err("DMA-API: error creating debugfs entries - disabling\n");
global_disable = true;
- return;
+ return 0;
}
if (req_entries)
num_entries = req_entries;
+ else
+ num_entries = PREALLOC_DMA_DEBUG_ENTRIES;
if (prealloc_memory(num_entries) != 0) {
pr_err("DMA-API: debugging out of memory error - disabled\n");
global_disable = true;
- return;
+ return 0;
}
nr_total_entries = num_free_entries;
@@ -1044,7 +1049,9 @@ void dma_debug_init(u32 num_entries)
dma_debug_initialized = true;
pr_info("DMA-API: debugging enabled by kernel config\n");
+ return 0;
}
+core_initcall(dma_debug_init);
I think it's worth noting that for most users this now happens much
earlier than before. In general that's probably good (e.g. on arm64 it
should prevent false-positives from the Arm SMMU drivers under ACPI),
and I can't imagine it's high-risk, but it is a behaviour change.
Robin.
static __init int dma_debug_cmdline(char *str)
{