[SYCL][Docs] Clarify virtual memory accessibility #20576
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This commit adds wording specifying that access mode applies to all devices in the context for which the corresponding memory is accessible. Signed-off-by: Larsen, Steffen <[email protected]>
| result in undefined behavior. | ||
| result in undefined behavior. The accessibility applies to all devices in | ||
| the context associated with this instance of `physical_mem` from which the | ||
| physical memory is reachable. |
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Under what circumstances would the physical memory be reachable from another device? I assume this would only be the case if the application used sycl_ext_oneapi_peer_access to enable peer-to-peer access? If that is the case, I think we should word it more explicitly:
If other devices have enabled peer-to-peer access with this device via sycl_ext_oneapi_peer_access, those other devices also have access to this mapped memory, and the access mode applies to accesses from those devices also.
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@steffenlarsen Thanks for the update. Overall, it looks good to me.
I'd just like to confirm that sycl_ext_oneapi_peer_access only affects the regular allocation (e.g., those returned by sycl::aligned_alloc_device) and doesn't impact virtual memory introduced in this extension. The access mode for virtual memory should only be controlled by the APIs explicitly mentioned in this extension, right?
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This commit adds wording specifying that access mode applies to all devices in the context for which the corresponding memory is accessible.