bpf: Introduce BPF_F_CPU and BPF_F_ALL_CPUS flags for percpu maps #6424
+560
−85
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Author
|
Upstream branch: 5262cb2 |
kernel-patches-daemon-bpf-rc
bot
force-pushed
the
bpf-next_base
branch
from
399fdcb to
8c83cb5
Compare
Introduce BPF_F_CPU and BPF_F_ALL_CPUS flags and check them for following APIs: * 'map_lookup_elem()' * 'map_update_elem()' * 'generic_map_lookup_batch()' * 'generic_map_update_batch()' And, get the correct value size for these APIs. Acked-by: Andrii Nakryiko <[email protected]> Signed-off-by: Leon Hwang <[email protected]>
…maps Introduce support for the BPF_F_ALL_CPUS flag in percpu_array maps to allow updating values for all CPUs with a single value for both update_elem and update_batch APIs. Introduce support for the BPF_F_CPU flag in percpu_array maps to allow: * update value for specified CPU for both update_elem and update_batch APIs. * lookup value for specified CPU for both lookup_elem and lookup_batch APIs. The BPF_F_CPU flag is passed via: * map_flags of lookup_elem and update_elem APIs along with embedded cpu info. * elem_flags of lookup_batch and update_batch APIs along with embedded cpu info. Signed-off-by: Leon Hwang <[email protected]>
…nd lru_percpu_hash maps Introduce BPF_F_ALL_CPUS flag support for percpu_hash and lru_percpu_hash maps to allow updating values for all CPUs with a single value for both update_elem and update_batch APIs. Introduce BPF_F_CPU flag support for percpu_hash and lru_percpu_hash maps to allow: * update value for specified CPU for both update_elem and update_batch APIs. * lookup value for specified CPU for both lookup_elem and lookup_batch APIs. The BPF_F_CPU flag is passed via: * map_flags along with embedded cpu info. * elem_flags along with embedded cpu info. Signed-off-by: Leon Hwang <[email protected]>
…ge maps Copy map value using 'copy_map_value_long()'. It's to keep consistent style with the way of other percpu maps. No functional change intended. Signed-off-by: Leon Hwang <[email protected]>
…_storage maps Introduce BPF_F_ALL_CPUS flag support for percpu_cgroup_storage maps to allow updating values for all CPUs with a single value for update_elem API. Introduce BPF_F_CPU flag support for percpu_cgroup_storage maps to allow: * update value for specified CPU for update_elem API. * lookup value for specified CPU for lookup_elem API. The BPF_F_CPU flag is passed via map_flags along with embedded cpu info. Signed-off-by: Leon Hwang <[email protected]>
Add libbpf support for the BPF_F_CPU flag for percpu maps by embedding the cpu info into the high 32 bits of: 1. **flags**: bpf_map_lookup_elem_flags(), bpf_map__lookup_elem(), bpf_map_update_elem() and bpf_map__update_elem() 2. **opts->elem_flags**: bpf_map_lookup_batch() and bpf_map_update_batch() And the flag can be BPF_F_ALL_CPUS, but cannot be 'BPF_F_CPU | BPF_F_ALL_CPUS'. Behavior: * If the flag is BPF_F_ALL_CPUS, the update is applied across all CPUs. * If the flag is BPF_F_CPU, it updates value only to the specified CPU. * If the flag is BPF_F_CPU, lookup value only from the specified CPU. * lookup does not support BPF_F_ALL_CPUS. Acked-by: Andrii Nakryiko <[email protected]> Signed-off-by: Leon Hwang <[email protected]>
Add test coverage for the new BPF_F_CPU and BPF_F_ALL_CPUS flags support in percpu maps. The following APIs are exercised: * bpf_map_update_batch() * bpf_map_lookup_batch() * bpf_map_update_elem() * bpf_map__update_elem() * bpf_map_lookup_elem_flags() * bpf_map__lookup_elem() For lru_percpu_hash map, set max_entries to 'libbpf_num_possible_cpus() + 1' and only use the first 'libbpf_num_possible_cpus()' entries. This ensures a spare entry is always available in the LRU free list, avoiding eviction. When updating an existing key in lru_percpu_hash map: 1. l_new = prealloc_lru_pop(); /* Borrow from free list */ 2. l_old = lookup_elem_raw(); /* Found, key exists */ 3. pcpu_copy_value(); /* In-place update */ 4. bpf_lru_push_free(); /* Return l_new to free list */ Also add negative tests to verify that non-percpu array and hash maps reject the BPF_F_CPU and BPF_F_ALL_CPUS flags. Signed-off-by: Leon Hwang <[email protected]>
Author
|
Upstream branch: 688b745 |
kernel-patches-daemon-bpf-rc
bot
force-pushed
the
series/1027896=>bpf-next
branch
from
f1d69c8 to
efb2917
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Pull request for series with
subject: bpf: Introduce BPF_F_CPU and BPF_F_ALL_CPUS flags for percpu maps
version: 12
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=1027896