Messages in this thread | | | From | "Adam J. Richter" <> | Date | Thu, 30 May 2002 02:11:12 -0700 | Subject | Does pci_alloc_consisent really need to zero memory? |
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Is it really necessary for pci_alloc_consistent() to fill the memory that it returns with all zeroes? I don't see anything in Documentation/DMA-mapping.txt that specifies it. I have been on the lookout for drivers that rely on it for the past couple of months, and I haven't seen any. It's only one line of code in arch/i386/kernel/pci-dma.c, but it is potentially a lot of cycles, even if only zeroes the space you requested (rather than the full pages that it actually allocates).
If nobody objects in the next half day or so (or asks me to follow some other course of action), I'll submit a patch for 2.5 for all architectures.
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