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Diffstat (limited to 'Documentation/aoe/todo.txt')
-rw-r--r-- | Documentation/aoe/todo.txt | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/Documentation/aoe/todo.txt b/Documentation/aoe/todo.txt new file mode 100644 index 000000000000..7fee1e1165bc --- /dev/null +++ b/Documentation/aoe/todo.txt | |||
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1 | There is a potential for deadlock when allocating a struct sk_buff for | ||
2 | data that needs to be written out to aoe storage. If the data is | ||
3 | being written from a dirty page in order to free that page, and if | ||
4 | there are no other pages available, then deadlock may occur when a | ||
5 | free page is needed for the sk_buff allocation. This situation has | ||
6 | not been observed, but it would be nice to eliminate any potential for | ||
7 | deadlock under memory pressure. | ||
8 | |||
9 | Because ATA over Ethernet is not fragmented by the kernel's IP code, | ||
10 | the destructore member of the struct sk_buff is available to the aoe | ||
11 | driver. By using a mempool for allocating all but the first few | ||
12 | sk_buffs, and by registering a destructor, we should be able to | ||
13 | efficiently allocate sk_buffs without introducing any potential for | ||
14 | deadlock. | ||