Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

dma-debug: remove broken dma memory leak detection for 2.6.30

Browse source 
The feature needs some more work because the notfier which is used to
check for pending allocations is called before the device drivers
->remove() function. Therefore this feature reports false positives.

A real fix for this issue is to introduce a new notifier event which sent
_after_ the driver has deinitialized itself. That will done for the next
kernel version.

[ Impact: reduce the scope of CONFIG_DMA_API_DEBUG=y checks ]

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
LKML-Reference: <1240576557-22442-1-git-send-email-joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Joerg Roedel 2009-04-24 14:35:57 +02:00 committed by Ingo Molnar
parent 992d7ced75
commit 314eeac9e3
1 changed files with 1 additions and 52 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

53
lib/dma-debug.c
View file

@ -400,60 +400,9 @@ static int dma_debug_fs_init(void)
return -ENOMEM;
}
static int device_dma_allocations(struct device *dev)
{
struct dma_debug_entry *entry;
unsigned long flags;
int count = 0, i;
for (i = 0; i < HASH_SIZE; ++i) {
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;
}
spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
}
return count;
}
static int dma_debug_device_change(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
int count;
switch (action) {
case BUS_NOTIFY_UNBIND_DRIVER:
count = device_dma_allocations(dev);
if (count == 0)
break;
err_printk(dev, NULL, "DMA-API: device driver has pending "
"DMA allocations while released from device "
"[count=%d]\n", count);
break;
default:
break;
}
return 0;
}
void dma_debug_add_bus(struct bus_type *bus)
{
struct notifier_block *nb;
nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
if (nb == NULL) {
printk(KERN_ERR "dma_debug_add_bus: out of memory\n");
return;
}
nb->notifier_call = dma_debug_device_change;
bus_register_notifier(bus, nb);
/* FIXME: register notifier */
}
/*