Messages in this thread | | | Date | Wed, 08 Dec 2010 11:18:04 +0200 | From | Avi Kivity <> | Subject | Re: [PATCH 07/15] ftrace: fix event alignment: kvm:kvm_hv_hypercall |
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On 12/07/2010 11:16 PM, David Sharp wrote: > > > > I don't understand this. Can you elaborate? What does "32-bit addressable" > > mean? > > The ring buffer gives you space that is a multiple of 4 bytes in > length, and 32-bit aligned. Therefore it is useless to attempt to > align the structure beyond 32-bit boundaries, eg, a 64-bit boundary, > because it is unpredictable if the memory the structure will be > written to is at a 64-bit boundary (addr % 8 could be 0 or 4). > > > And "predicated on packing the event structures"? Is the structure > > __attribute__((packed)), or is it not? > > It is not packed in Linus' tree, but one of the patches before this > patch in this patch series adds __attribute__((packed)). This patch > assumes that the event packing patch has been applied. This patch > should not be applied if the packing patch is not (hence, > "predicated").
Thanks for the explanations, it makes sense now.
-- error compiling committee.c: too many arguments to function
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