Re: [PATCH v2 bpf-next 4/4] selftests/bpf: add auto-detach test
On 5/23/19 10:58 AM, Roman Gushchin wrote: > On Wed, May 22, 2019 at 10:47:24PM -0700, Yonghong Song wrote: >> >> >> On 5/22/19 4:20 PM, Roman Gushchin wrote: >>> Add a kselftest to cover bpf auto-detachment functionality. >>> The test creates a cgroup, associates some resources with it, >>> attaches a couple of bpf programs and deletes the cgroup. >>> >>> Then it checks that bpf programs are going away in 5 seconds. >>> >>> Expected output: >>> $ ./test_cgroup_attach >>> #override:PASS >>> #multi:PASS >>> #autodetach:PASS >>> test_cgroup_attach:PASS >>> >>> On a kernel without auto-detaching: >>> $ ./test_cgroup_attach >>> #override:PASS >>> #multi:PASS >>> #autodetach:FAIL >>> test_cgroup_attach:FAIL >> >> I ran this problem without both old and new kernels and >> both get all PASSes. My testing environment is a VM. >> Could you specify how to trigger the above failure? > > Most likely you're running cgroup v1, so the memory controller > is not enabled on unified hierarchy. You need to pass > "cgroup_no_v1=all systemd.unified_cgroup_hierarchy=1" > as boot time options to run fully on cgroup v2. I tested on a cgroup v2 machine and it indeed failed without the core patch. Thanks! > > But generally speaking, the lifecycle of a dying cgroup is > completely implementation-defined. No guarantees are provided. > So false positives are fine here, and shouldn't be considered as > something bad. > > At the end all we want it to detach programs in a reasonable time > after rmdir. > > Btw, thank you for the careful review of the patchset. I'll > address your comments, add acks and will send out v3. > > Thanks! >
Re: [PATCH v2 bpf-next 4/4] selftests/bpf: add auto-detach test
On Wed, May 22, 2019 at 10:47:24PM -0700, Yonghong Song wrote: > > > On 5/22/19 4:20 PM, Roman Gushchin wrote: > > Add a kselftest to cover bpf auto-detachment functionality. > > The test creates a cgroup, associates some resources with it, > > attaches a couple of bpf programs and deletes the cgroup. > > > > Then it checks that bpf programs are going away in 5 seconds. > > > > Expected output: > >$ ./test_cgroup_attach > >#override:PASS > >#multi:PASS > >#autodetach:PASS > >test_cgroup_attach:PASS > > > > On a kernel without auto-detaching: > >$ ./test_cgroup_attach > >#override:PASS > >#multi:PASS > >#autodetach:FAIL > >test_cgroup_attach:FAIL > > I ran this problem without both old and new kernels and > both get all PASSes. My testing environment is a VM. > Could you specify how to trigger the above failure? Most likely you're running cgroup v1, so the memory controller is not enabled on unified hierarchy. You need to pass "cgroup_no_v1=all systemd.unified_cgroup_hierarchy=1" as boot time options to run fully on cgroup v2. But generally speaking, the lifecycle of a dying cgroup is completely implementation-defined. No guarantees are provided. So false positives are fine here, and shouldn't be considered as something bad. At the end all we want it to detach programs in a reasonable time after rmdir. Btw, thank you for the careful review of the patchset. I'll address your comments, add acks and will send out v3. Thanks!
Re: [PATCH v2 bpf-next 4/4] selftests/bpf: add auto-detach test
On 5/22/19 4:20 PM, Roman Gushchin wrote:
> Add a kselftest to cover bpf auto-detachment functionality.
> The test creates a cgroup, associates some resources with it,
> attaches a couple of bpf programs and deletes the cgroup.
>
> Then it checks that bpf programs are going away in 5 seconds.
>
> Expected output:
>$ ./test_cgroup_attach
>#override:PASS
>#multi:PASS
>#autodetach:PASS
>test_cgroup_attach:PASS
>
> On a kernel without auto-detaching:
>$ ./test_cgroup_attach
>#override:PASS
>#multi:PASS
>#autodetach:FAIL
>test_cgroup_attach:FAIL
>
> Signed-off-by: Roman Gushchin
> ---
> .../selftests/bpf/test_cgroup_attach.c| 99 ++-
> 1 file changed, 98 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/bpf/test_cgroup_attach.c
> b/tools/testing/selftests/bpf/test_cgroup_attach.c
> index 93d4fe295e7d..bc5bd0f1728e 100644
> --- a/tools/testing/selftests/bpf/test_cgroup_attach.c
> +++ b/tools/testing/selftests/bpf/test_cgroup_attach.c
> @@ -456,9 +456,106 @@ static int test_multiprog(void)
> return rc;
> }
>
> +static int test_autodetach(void)
> +{
> + __u32 prog_cnt = 4, attach_flags;
> + int allow_prog[2] = {0};
> + __u32 prog_ids[2] = {0};
> + int cg = 0, i, rc = -1;
> + void *ptr = NULL;
> + int attempts;
> +
> +
Also extra line here.
> + for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
> + allow_prog[i] = prog_load_cnt(1, 1 << i);
> + if (!allow_prog[i])
> + goto err;
> + }
> +
> + if (setup_cgroup_environment())
> + goto err;
> +
> + /* create a cgroup, attach two programs and remember their ids */
> + cg = create_and_get_cgroup("/cg_autodetach");
[...]
> +
> int main(int argc, char **argv)
> {
> - int (*tests[])(void) = {test_foo_bar, test_multiprog};
> + int (*tests[])(void) = {
> + test_foo_bar,
> + test_multiprog,
> + test_autodetach,
> + };
> int errors = 0;
> int i;
>
>
Re: [PATCH v2 bpf-next 4/4] selftests/bpf: add auto-detach test
On 5/22/19 4:20 PM, Roman Gushchin wrote:
> Add a kselftest to cover bpf auto-detachment functionality.
> The test creates a cgroup, associates some resources with it,
> attaches a couple of bpf programs and deletes the cgroup.
>
> Then it checks that bpf programs are going away in 5 seconds.
>
> Expected output:
>$ ./test_cgroup_attach
>#override:PASS
>#multi:PASS
>#autodetach:PASS
>test_cgroup_attach:PASS
>
> On a kernel without auto-detaching:
>$ ./test_cgroup_attach
>#override:PASS
>#multi:PASS
>#autodetach:FAIL
>test_cgroup_attach:FAIL
I ran this problem without both old and new kernels and
both get all PASSes. My testing environment is a VM.
Could you specify how to trigger the above failure?
>
> Signed-off-by: Roman Gushchin
> ---
> .../selftests/bpf/test_cgroup_attach.c| 99 ++-
> 1 file changed, 98 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/bpf/test_cgroup_attach.c
> b/tools/testing/selftests/bpf/test_cgroup_attach.c
> index 93d4fe295e7d..bc5bd0f1728e 100644
> --- a/tools/testing/selftests/bpf/test_cgroup_attach.c
> +++ b/tools/testing/selftests/bpf/test_cgroup_attach.c
> @@ -456,9 +456,106 @@ static int test_multiprog(void)
> return rc;
> }
>
> +static int test_autodetach(void)
> +{
> + __u32 prog_cnt = 4, attach_flags;
> + int allow_prog[2] = {0};
> + __u32 prog_ids[2] = {0};
> + int cg = 0, i, rc = -1;
> + void *ptr = NULL;
> + int attempts;
> +
> +
> + for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
> + allow_prog[i] = prog_load_cnt(1, 1 << i);
> + if (!allow_prog[i])
> + goto err;
> + }
> +
> + if (setup_cgroup_environment())
> + goto err;
> +
> + /* create a cgroup, attach two programs and remember their ids */
> + cg = create_and_get_cgroup("/cg_autodetach");
> + if (cg < 0)
> + goto err;
> +
> + if (join_cgroup("/cg_autodetach"))
> + goto err;
> +
> + for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
> + if (bpf_prog_attach(allow_prog[i], cg, BPF_CGROUP_INET_EGRESS,
> + BPF_F_ALLOW_MULTI)) {
> + log_err("Attaching prog[%d] to cg:egress", i);
> + goto err;
> + }
> + }
> +
> + /* make sure that programs are attached and run some traffic */
> + assert(bpf_prog_query(cg, BPF_CGROUP_INET_EGRESS, 0, _flags,
> + prog_ids, _cnt) == 0);
> + assert(system(PING_CMD) == 0);
> +
> + /* allocate some memory (4Mb) to pin the original cgroup */
> + ptr = malloc(4 * (1 << 20));
> + if (!ptr)
> + goto err;
> +
> + /* close programs and cgroup fd */
> + for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
> + close(allow_prog[i]);
> + allow_prog[i] = 0;
> + }
> +
> + close(cg);
> + cg = 0;
> +
> + /* leave the cgroup and remove it. don't detach programs */
> + cleanup_cgroup_environment();
> +
> + /* wait for the asynchronous auto-detachment.
> + * wait for no more than 5 sec and give up.
> + */
> + for (i = 0; i < ARRAY_SIZE(prog_ids); i++) {
> + for (attempts = 5; attempts >= 0; attempts--) {
> + int fd = bpf_prog_get_fd_by_id(prog_ids[i]);
> +
> + if (fd < 0)
> + break;
> +
> + /* don't leave the fd open */
> + close(fd);
> +
> + if (!attempts)
> + goto err;
> +
> + sleep(1);
> + }
> + }
> +
> + rc = 0;
> +err:
> + for (i = 0; i < ARRAY_SIZE(allow_prog); i++)
> + if (allow_prog[i] > 0)
> + close(allow_prog[i]);
> + if (cg)
> + close(cg);
> + free(ptr);
> + cleanup_cgroup_environment();
> + if (!rc)
> + printf("#autodetach:PASS\n");
> + else
> + printf("#autodetach:FAIL\n");
> + return rc;
> +}
> +
> int main(int argc, char **argv)
> {
> - int (*tests[])(void) = {test_foo_bar, test_multiprog};
> + int (*tests[])(void) = {
> + test_foo_bar,
> + test_multiprog,
> + test_autodetach,
> + };
> int errors = 0;
> int i;
>
>
[PATCH v2 bpf-next 4/4] selftests/bpf: add auto-detach test
Add a kselftest to cover bpf auto-detachment functionality.
The test creates a cgroup, associates some resources with it,
attaches a couple of bpf programs and deletes the cgroup.
Then it checks that bpf programs are going away in 5 seconds.
Expected output:
$ ./test_cgroup_attach
#override:PASS
#multi:PASS
#autodetach:PASS
test_cgroup_attach:PASS
On a kernel without auto-detaching:
$ ./test_cgroup_attach
#override:PASS
#multi:PASS
#autodetach:FAIL
test_cgroup_attach:FAIL
Signed-off-by: Roman Gushchin
---
.../selftests/bpf/test_cgroup_attach.c| 99 ++-
1 file changed, 98 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/test_cgroup_attach.c
b/tools/testing/selftests/bpf/test_cgroup_attach.c
index 93d4fe295e7d..bc5bd0f1728e 100644
--- a/tools/testing/selftests/bpf/test_cgroup_attach.c
+++ b/tools/testing/selftests/bpf/test_cgroup_attach.c
@@ -456,9 +456,106 @@ static int test_multiprog(void)
return rc;
}
+static int test_autodetach(void)
+{
+ __u32 prog_cnt = 4, attach_flags;
+ int allow_prog[2] = {0};
+ __u32 prog_ids[2] = {0};
+ int cg = 0, i, rc = -1;
+ void *ptr = NULL;
+ int attempts;
+
+
+ for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
+ allow_prog[i] = prog_load_cnt(1, 1 << i);
+ if (!allow_prog[i])
+ goto err;
+ }
+
+ if (setup_cgroup_environment())
+ goto err;
+
+ /* create a cgroup, attach two programs and remember their ids */
+ cg = create_and_get_cgroup("/cg_autodetach");
+ if (cg < 0)
+ goto err;
+
+ if (join_cgroup("/cg_autodetach"))
+ goto err;
+
+ for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
+ if (bpf_prog_attach(allow_prog[i], cg, BPF_CGROUP_INET_EGRESS,
+ BPF_F_ALLOW_MULTI)) {
+ log_err("Attaching prog[%d] to cg:egress", i);
+ goto err;
+ }
+ }
+
+ /* make sure that programs are attached and run some traffic */
+ assert(bpf_prog_query(cg, BPF_CGROUP_INET_EGRESS, 0, _flags,
+ prog_ids, _cnt) == 0);
+ assert(system(PING_CMD) == 0);
+
+ /* allocate some memory (4Mb) to pin the original cgroup */
+ ptr = malloc(4 * (1 << 20));
+ if (!ptr)
+ goto err;
+
+ /* close programs and cgroup fd */
+ for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
+ close(allow_prog[i]);
+ allow_prog[i] = 0;
+ }
+
+ close(cg);
+ cg = 0;
+
+ /* leave the cgroup and remove it. don't detach programs */
+ cleanup_cgroup_environment();
+
+ /* wait for the asynchronous auto-detachment.
+* wait for no more than 5 sec and give up.
+*/
+ for (i = 0; i < ARRAY_SIZE(prog_ids); i++) {
+ for (attempts = 5; attempts >= 0; attempts--) {
+ int fd = bpf_prog_get_fd_by_id(prog_ids[i]);
+
+ if (fd < 0)
+ break;
+
+ /* don't leave the fd open */
+ close(fd);
+
+ if (!attempts)
+ goto err;
+
+ sleep(1);
+ }
+ }
+
+ rc = 0;
+err:
+ for (i = 0; i < ARRAY_SIZE(allow_prog); i++)
+ if (allow_prog[i] > 0)
+ close(allow_prog[i]);
+ if (cg)
+ close(cg);
+ free(ptr);
+ cleanup_cgroup_environment();
+ if (!rc)
+ printf("#autodetach:PASS\n");
+ else
+ printf("#autodetach:FAIL\n");
+ return rc;
+}
+
int main(int argc, char **argv)
{
- int (*tests[])(void) = {test_foo_bar, test_multiprog};
+ int (*tests[])(void) = {
+ test_foo_bar,
+ test_multiprog,
+ test_autodetach,
+ };
int errors = 0;
int i;
--
2.20.1
