From 9f191555ba4ba8fc82e589670e46a7f79b72a157 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Mon, 10 Dec 2018 14:00:28 +0000 Subject: [PATCH] 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: John Garry Signed-off-by: Robin Murphy Tested-by: Qian Cai Signed-off-by: Christoph Hellwig --- Documentation/DMA-API.txt | 3 +++ kernel/dma/debug.c | 7 +++++++ 2 files changed, 10 insertions(+) diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index ac66ae2509a9..6bdb095393b0 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -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 diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 231ca4628062..f6a141eb9438 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -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) -- 2.30.2