Prevent Negative TIDs in Trace #1002
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Summary: Right now we take the TIDs returned from CUPTI and convert them from int64_t to int32_t which results in negative tids. Because Perfetto uses int32_t in its protobuf files (according to google/perfetto#886) we can't just convert to uint32_t because perfetto will just convert values back into their negative counterparts. To fix this, we convert to only positive values in int32_t by finding the absolute value of the original int32_t representation of the tid. We also make a special case for INT_MIN to map to 0 so that it is apparent how we handle overflow. We add this sanitization to all tid outputs for hygiene purposes instead of just CUPTI output. Differential Revision: D64490195
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This pull request was exported from Phabricator. Differential Revision: D64490195 |
ngimel
approved these changes
Oct 16, 2024
sanrise
approved these changes
Oct 16, 2024
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This pull request has been merged in eb1713f. |
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Summary:
Right now we take the TIDs returned from CUPTI and convert them from int64_t to int32_t which results in negative tids. Because Perfetto uses int32_t in its protobuf files (according to google/perfetto#886) we can't just convert to uint32_t because perfetto will just convert values back into their negative counterparts. To fix this, we convert to only positive values in int32_t by finding the absolute value of the original int32_t representation of the tid. We also make a special case for INT_MIN to map to 0 so that it is apparent how we handle overflow.
We add this sanitization to all tid outputs for hygiene purposes instead of just CUPTI output.
Differential Revision: D64490195