Commit 9f191555 authored by Robin Murphy's avatar Robin Murphy Committed by Christoph Hellwig
Browse files

dma-debug: Expose nr_total_entries in debugfs 



Expose nr_total_entries in debugfs, so that {num,min}_free_entries
become even more meaningful to users interested in current/maximum
utilisation. This becomes even more relevant once nr_total_entries
may change at runtime beyond just the existing AMD GART debug code.

Suggested-by: default avatarJohn Garry <john.garry@huawei.com>
Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Tested-by: default avatarQian Cai <cai@lca.pw>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 7c703e54

Documentation/DMA-API.txt

+3 −0
Original line number Diff line number Diff line
@@ -723,6 +723,9 @@ dma-api/min_free_entries This read-only file can be read to get the 
dma-api/num_free_entries	The current number of free dma_debug_entries

				in the allocator.



dma-api/nr_total_entries	The total number of dma_debug_entries in the

				allocator, both free and used.



dma-api/driver-filter		You can write a name of a driver into this file

				to limit the debug output to requests from that

				particular driver. Write an empty string to

kernel/dma/debug.c

+7 −0
Original line number Diff line number Diff line
@@ -142,6 +142,7 @@ static struct dentry *show_all_errors_dent __read_mostly; 
static struct dentry *show_num_errors_dent  __read_mostly;

static struct dentry *num_free_entries_dent __read_mostly;

static struct dentry *min_free_entries_dent __read_mostly;

static struct dentry *nr_total_entries_dent __read_mostly;

static struct dentry *filter_dent           __read_mostly;



/* per-driver filter related state */
@@ -926,6 +927,12 @@ static int dma_debug_fs_init(void) 
	if (!min_free_entries_dent)

		goto out_err;



	nr_total_entries_dent = debugfs_create_u32("nr_total_entries", 0444,

			dma_debug_dent,

			&nr_total_entries);

	if (!nr_total_entries_dent)

		goto out_err;



	filter_dent = debugfs_create_file("driver_filter", 0644,

					  dma_debug_dent, NULL, &filter_fops);

	if (!filter_dent)

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