Eliminate unneeded interlocked operation on LPM updates #3239
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Signed-off-by: Alan Jowett <[email protected]>
Alan-Jowett
requested review from
dthaler,
poornagmsft,
saxena-anurag,
shankarseal,
dv-msft,
gtrevi,
shpalani,
matthewige,
mtfriesen and
rectified95
as code owners
rectified95
approved these changes
Feb 5, 2024
shankarseal
approved these changes
Feb 5, 2024
dthaler
reviewed
Feb 6, 2024
| @@ -1651,7 +1651,10 @@ _update_lpm_map_entry( | |||
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| ebpf_result_t result = _update_hash_map_entry(map, key, data, option); | |||
| if (result == EBPF_SUCCESS) { | |||
| ebpf_bitmap_set_bit((ebpf_bitmap_t*)trie_map->data, prefix_length, true); | |||
| // Test if the bit is set before setting it. This avoids the overhead of a the interlocked operation. | |||
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@Alan-Jowett Please fix grammar around "a the"
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Description
LPM tracks prefix lengths stored in the hash-table via a bitmap. This bitmap is only ever added to (never removed) so unconditionally doing an interlocked test and set is excessive.
Possibly related to: #3016
Testing
CI/CD
Documentation
No.
Installation
No.