This Patch add a test to prove css_task iter can be used in normal
sleepable progs.
Signed-off-by: Chuyi Zhou <zhouchuyi@bytedance.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20231031050438.93297-4-zhouchuyi@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds 4 subtests to demonstrate these patterns and validating
correctness.
subtest1:
1) We use task_iter to iterate all process in the system and search for the
current process with a given pid.
2) We create some threads in current process context, and use
BPF_TASK_ITER_PROC_THREADS to iterate all threads of current process. As
expected, we would find all the threads of current process.
3) We create some threads and use BPF_TASK_ITER_ALL_THREADS to iterate all
threads in the system. As expected, we would find all the threads which was
created.
subtest2:
We create a cgroup and add the current task to the cgroup. In the
BPF program, we would use bpf_for_each(css_task, task, css) to iterate all
tasks under the cgroup. As expected, we would find the current process.
subtest3:
1) We create a cgroup tree. In the BPF program, we use
bpf_for_each(css, pos, root, XXX) to iterate all descendant under the root
with pre and post order. As expected, we would find all descendant and the
last iterating cgroup in post-order is root cgroup, the first iterating
cgroup in pre-order is root cgroup.
2) We wse BPF_CGROUP_ITER_ANCESTORS_UP to traverse the cgroup tree starting
from leaf and root separately, and record the height. The diff of the
hights would be the total tree-high - 1.
subtest4:
Add some failure testcase when using css_task, task and css iters, e.g,
unlock when using task-iters to iterate tasks.
Signed-off-by: Chuyi Zhou <zhouchuyi@bytedance.com>
Link: https://lore.kernel.org/r/20231018061746.111364-9-zhouchuyi@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The open-coded task_vma iter added earlier in this series allows for
natural iteration over a task's vmas using existing open-coded iter
infrastructure, specifically bpf_for_each.
This patch adds a test demonstrating this pattern and validating
correctness. The vma->vm_start and vma->vm_end addresses of the first
1000 vmas are recorded and compared to /proc/PID/maps output. As
expected, both see the same vmas and addresses - with the exception of
the [vsyscall] vma - which is explained in a comment in the prog_tests
program.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20231013204426.1074286-5-davemarchevsky@fb.com
Implement a trivial iterator returning same specified integer value
N times as part of bpf_testmod kernel module. Add selftests to validate
everything works end to end.
We also reuse these tests as "verification-only" tests to validate that
kernel prints the state of custom kernel module-defined iterator correctly:
fp-16=iter_testmod_seq(ref_id=1,state=drained,depth=0)
"testmod_seq" part is an iterator type, and is coming from module's BTF
data dynamically at runtime.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230308184121.1165081-9-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add number iterator (bpf_iter_num_{new,next,destroy}()) tests,
validating the correct handling of various corner and common cases
*at runtime*.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230308184121.1165081-8-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add various tests for open-coded iterators. Some of them excercise
various possible coding patterns in C, some go down to low-level
assembly for more control over various conditions, especially invalid
ones.
We also make use of bpf_for(), bpf_for_each(), bpf_repeat() macros in
some of these tests.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230308184121.1165081-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
