Messages in this thread | | | Date | Sat, 10 Jul 2010 15:52:04 +0100 | Subject | Re: [2.6.35-rc3] select useful number of entries for DMA debugging... | From | Daniel J Blueman <> |
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On 9 July 2010 22:33, Linus Torvalds <torvalds@linux-foundation.org> wrote: > On Mon, Jul 5, 2010 at 1:35 AM, Daniel J Blueman > <daniel.blueman@gmail.com> wrote: >> When booting 2.6.35-rc3 on some different x86 boxes with DMA debugging >> enabled, I've consistently seen it exhaust the allocated entries during >> boot, giving 'DMA-API: debugging out of memory - disabling'. >> >> Increase number of entries to allow DMA debugging again. > > Rather than increase the default that gets allocated whenever anybody > enables the DMA debugging, I'd really prefer to see people use the > kernel command line option if they run out. After all, it's a (pretty > esoteric) debug option, and the number of required entries depends on > machine configuration. I'd rather not make the default cover a huge > number, when you could just add > > dma_debug_entries=65536 > > on the kernel boot command line instead for machines that want/need it..
That said, I am seeing the DMA pool exhaust on a single socket Core i5 system with Intel graphics and no other adapters - seems like a fairly common case. If eg 25% of developers will be using similar to this, maybe it's good to make DMA debugging less immediately esoteric?
On the other hand, I would immediately agree if the exhaustion occurred on an atypical setup. -- Daniel J Blueman -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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