kernel/tools/testing/selftests/bpf/progs/timer.c, branch linux-rolling-stable

selftests/bpf: Use bpf_tracing.h instead of bpf_tcp_helpers.h

2024-05-06T20:40:24Z

The bpf programs that this patch changes require the BPF_PROG macro. The BPF_PROG macro is defined in the libbpf's bpf_tracing.h. Some tests include bpf_tcp_helpers.h which includes bpf_tracing.h. They don't need other things from bpf_tcp_helpers.h other than bpf_tracing.h. This patch simplifies it by directly including the bpf_tracing.h. The motivation of this unnecessary code churn is to retire the bpf_tcp_helpers.h by directly using vmlinux.h. Right now, the main usage of the bpf_tcp_helpers.h is the partial kernel socket definitions (e.g. socket, sock, tcp_sock). While the test cases continue to grow, fields are kept adding to those partial socket definitions (e.g. the recent bpf_cc_cubic.c test which tried to extend bpf_tcp_helpers.c but eventually used the vmlinux.h instead). The idea is to retire bpf_tcp_helpers.c and consistently use vmlinux.h for the tests that require the kernel sockets. This patch tackles the obvious tests that can directly use bpf_tracing.h instead of bpf_tcp_helpers.h. Signed-off-by: Martin KaFai Lau Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20240504005045.848376-1-martin.lau@linux.dev

selftests/bpf: Test racing between bpf_timer_cancel_and_free and bpf_timer_cancel

2024-02-19T11:26:46Z

This selftest is based on a Alexei's test adopted from an internal user to troubleshoot another bug. During this exercise, a separate racing bug was discovered between bpf_timer_cancel_and_free and bpf_timer_cancel. The details can be found in the previous patch. This patch is to add a selftest that can trigger the bug. I can trigger the UAF everytime in my qemu setup with KASAN. The idea is to have multiple user space threads running in a tight loop to exercise both bpf_map_update_elem (which calls into bpf_timer_cancel_and_free) and bpf_timer_cancel. Signed-off-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann Acked-by: Hou Tao Link: https://lore.kernel.org/bpf/20240215211218.990808-2-martin.lau@linux.dev

selftests/bpf: Test pinning bpf timer to a core

2023-10-09T14:29:06Z

Now that we support pinning a BPF timer to the current core, we should test it with some selftests. This patch adds two new testcases to the timer suite, which verifies that a BPF timer both with and without BPF_F_TIMER_ABS, can be pinned to the calling core with BPF_F_TIMER_CPU_PIN. Signed-off-by: David Vernet Signed-off-by: Daniel Borkmann Acked-by: Song Liu Acked-by: Hou Tao Link: https://lore.kernel.org/bpf/20231004162339.200702-3-void@manifault.com

selftests/bpf: Add absolute timer test

2023-03-03T06:41:32Z

Add test for the absolute BPF timer under the existing timer tests. This will run the timer two times with 1us expiration time, and then re-arm the timer at ~35s in the future. At the end, it is verified that the absolute timer expired exactly two times. Signed-off-by: Tero Kristo Link: https://lore.kernel.org/r/20230302114614.2985072-3-tero.kristo@linux.intel.com Signed-off-by: Alexei Starovoitov

selftests/bpf: Use BPF_PROG2 for some fentry programs without struct arguments

2022-09-07T02:51:14Z

Use BPF_PROG2 instead of BPF_PROG for programs in progs/timer.c to test BPF_PROG2 for cases without struct arguments. Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20220831152718.2081091-1-yhs@fb.com Signed-off-by: Alexei Starovoitov

bpf: Optimize call_rcu in non-preallocated hash map.

2022-09-05T13:33:06Z

Doing call_rcu() million times a second becomes a bottle neck. Convert non-preallocated hash map from call_rcu to SLAB_TYPESAFE_BY_RCU. The rcu critical section is no longer observed for one htab element which makes non-preallocated hash map behave just like preallocated hash map. The map elements are released back to kernel memory after observing rcu critical section. This improves 'map_perf_test 4' performance from 100k events per second to 250k events per second. bpf_mem_alloc + percpu_counter + typesafe_by_rcu provide 10x performance boost to non-preallocated hash map and make it within few % of preallocated map while consuming fraction of memory. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Kumar Kartikeya Dwivedi Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220902211058.60789-8-alexei.starovoitov@gmail.com

selftests/bpf: Add bpf_timer test.

2021-07-15T20:31:11Z

Add bpf_timer test that creates timers in preallocated and non-preallocated hash, in array and in lru maps. Let array timer expire once and then re-arm it for 35 seconds. Arm lru timer into the same callback. Then arm and re-arm hash timers 10 times each. At the last invocation of prealloc hash timer cancel the array timer. Force timer free via LRU eviction and direct bpf_map_delete_elem. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20210715005417.78572-11-alexei.starovoitov@gmail.com