lib/dma-debug.c: make locking work for RT

Interrupt enable/disabled with spinlock is not a valid operation for RT
as it can make executing tasks sleep from a non-sleepable context.  So
convert it to spin_lock_irq[save, restore].

Link: http://lkml.kernel.org/r/1492065666-3816-1-git-send-email-pagupta@redhat.com
Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ville Syrjl <ville.syrjala@linux.intel.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index b157b46cc9a69ca830a2cdbc8abcbc9baab4a63e..fe4d50c992df618a914e4696d7f698e4e8b76c83 100644 (file)
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -942,21 +942,17 @@ static int device_dma_allocations(struct device *dev, struct dma_debug_entry **o
        unsigned long flags;
        int count = 0, i;
 
-       local_irq_save(flags);
-
        for (i = 0; i < HASH_SIZE; ++i) {
-               spin_lock(&dma_entry_hash[i].lock);
+               spin_lock_irqsave(&dma_entry_hash[i].lock, flags);
                list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
                        if (entry->dev == dev) {
                                count += 1;
                                *out_entry = entry;
                        }
                }
-               spin_unlock(&dma_entry_hash[i].lock);
+               spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
        }
 
-       local_irq_restore(flags);
-
        return count;
 }