Adding some chromium devs to the thread. In, http://lxr.free-electrons.com/source/mm/page_alloc.c#L3152 The default mm retry allocation when 'order <= PAGE_ALLOC_COSTLY_ORDER' of gfp_mask contains __GFP_REPEAT. PAGE_ALLOC_COSTLY_ORDER is defined to be 3. On systems with page size = 4K, this means memory compaction and retry is only done when the size of allocation is <= 32K In mwifiex, the allocation size is 64K. When we have system with memory fragmentation and allocation failed, there will be no retry. This is why we need to add __GFP_REPEAT here to allow the system to perform memory compaction and retry allocation. Maybe Amit@marvell can comment on if this is a good fix on this issue. I'm also aware that marvell is the progress of implementing scatter/gatter for mwifiex, which can also fix the issue. Wei-Ning On Tue, Mar 29, 2016 at 4:37 PM, Kalle Valo <kvalo@xxxxxxxxxxxxxx> wrote: > Wei-Ning Huang <wnhuang@xxxxxxxxxxxx> writes: > >> "single skb allocation failure" happens when system is under heavy >> memory pressure. Add __GFP_REPEAT to skb allocation call so kernel >> attempts to reclaim pages and retry the allocation. >> >> Signed-off-by: Wei-Ning Huang <wnhuang@xxxxxxxxxxxx> > > Is this really a proper way to fix the issue? This is the first time I'm > hearing about the flag and there isn't even a single user in > drivers/net. I would like to get confirmation from others that > __GFP_REPEAT is really ok to use in a wireless driver before I can take > this. > > -- > Kalle Valo -- Wei-Ning Huang, 黃偉寧 | Software Engineer, Google Inc., Taiwan | wnhuang@xxxxxxxxxx | Cell: +886 910-380678 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
