From: Hou Tao <houtao1@xxxxxxxxxx>
Hi,
This patch set fixes several issues for LPM trie. These issues were
found during adding new test cases or were reported by syzbot.
The patch set is structured as follows:
Patch #1~#2 are clean-ups for lpm_trie_update_elem().
Patch #3 handles BPF_EXIST and BPF_NOEXIST correctly for LPM trie.
Patch #4 fixes the accounting of n_entries when doing in-place update.
Patch #5 fixes the exact match condition in trie_get_next_key() and it
may skip keys when the passed key is not found in the map.
Patch #6~#7 switch from kmalloc() to bpf memory allocator for LPM trie
to fix several lock order warnings reported by syzbot. It also enables
raw_spinlock_t for LPM trie again. After these changes, the LPM trie will
be closer to being usable in any context (though the reentrance check of
trie->lock is still missing, but it is on my todo list).
Patch #8: move test_lpm_map to map_tests to make it run regularly.
Patch #9: add test cases for the issues fixed by patch #3~#5.
Please see individual patches for more details. Comments are always
welcome.
Change Log:
v3:
* patch #2: remove the unnecessary NULL-init for im_node
* patch #6: alloc the leaf node before disabling IRQ to low
the possibility of -ENOMEM when leaf_size is large; Free
these nodes outside the trie lock (Suggested by Alexei)
* collect review and ack tags (Thanks for Toke & Daniel)
v2: https://lore.kernel.org/bpf/20241127004641.1118269-1-houtao@xxxxxxxxxxxxxxx/
* collect review tags (Thanks for Toke)
* drop "Add bpf_mem_cache_is_mergeable() helper" patch
* patch #3~#4: add fix tag
* patch #4: rename the helper to trie_check_add_elem() and increase
n_entries in it.
* patch #6: use one bpf mem allocator and update commit message to
clarify that using bpf mem allocator is more appropriate.
* patch #7: update commit message to add the possible max running time
for update operation.
* patch #9: update commit message to specify the purpose of these test
cases.
v1: https://lore.kernel.org/bpf/20241118010808.2243555-1-houtao@xxxxxxxxxxxxxxx/
Hou Tao (9):
bpf: Remove unnecessary check when updating LPM trie
bpf: Remove unnecessary kfree(im_node) in lpm_trie_update_elem
bpf: Handle BPF_EXIST and BPF_NOEXIST for LPM trie
bpf: Handle in-place update for full LPM trie correctly
bpf: Fix exact match conditions in trie_get_next_key()
bpf: Switch to bpf mem allocator for LPM trie
bpf: Use raw_spinlock_t for LPM trie
selftests/bpf: Move test_lpm_map.c to map_tests
selftests/bpf: Add more test cases for LPM trie
kernel/bpf/lpm_trie.c | 133 +++---
tools/testing/selftests/bpf/.gitignore | 1 -
tools/testing/selftests/bpf/Makefile | 2 +-
.../lpm_trie_map_basic_ops.c} | 405 +++++++++++++++++-
4 files changed, 484 insertions(+), 57 deletions(-)
rename tools/testing/selftests/bpf/{test_lpm_map.c => map_tests/lpm_trie_map_basic_ops.c} (65%)
--
2.29.2
