selftests/bpf: Test pinning bpf timer to a core

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 <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20231004162339.200702-3-void@manifault.com
This commit is contained in:
David Vernet 2023-10-04 11:23:39 -05:00 committed by Daniel Borkmann
parent d6247ecb6c
commit 0d7ae06860
2 changed files with 66 additions and 1 deletions

View File

@ -14,6 +14,7 @@ static int timer(struct timer *timer_skel)
ASSERT_EQ(timer_skel->data->callback_check, 52, "callback_check1");
ASSERT_EQ(timer_skel->data->callback2_check, 52, "callback2_check1");
ASSERT_EQ(timer_skel->bss->pinned_callback_check, 0, "pinned_callback_check1");
prog_fd = bpf_program__fd(timer_skel->progs.test1);
err = bpf_prog_test_run_opts(prog_fd, &topts);
@ -32,6 +33,9 @@ static int timer(struct timer *timer_skel)
/* check that timer_cb3() was executed twice */
ASSERT_EQ(timer_skel->bss->abs_data, 12, "abs_data");
/* check that timer_cb_pinned() was executed twice */
ASSERT_EQ(timer_skel->bss->pinned_callback_check, 2, "pinned_callback_check");
/* check that there were no errors in timer execution */
ASSERT_EQ(timer_skel->bss->err, 0, "err");

View File

@ -51,7 +51,7 @@ struct {
__uint(max_entries, 1);
__type(key, int);
__type(value, struct elem);
} abs_timer SEC(".maps");
} abs_timer SEC(".maps"), soft_timer_pinned SEC(".maps"), abs_timer_pinned SEC(".maps");
__u64 bss_data;
__u64 abs_data;
@ -59,6 +59,8 @@ __u64 err;
__u64 ok;
__u64 callback_check = 52;
__u64 callback2_check = 52;
__u64 pinned_callback_check;
__s32 pinned_cpu;
#define ARRAY 1
#define HTAB 2
@ -329,3 +331,62 @@ int BPF_PROG2(test3, int, a)
return 0;
}
/* callback for pinned timer */
static int timer_cb_pinned(void *map, int *key, struct bpf_timer *timer)
{
__s32 cpu = bpf_get_smp_processor_id();
if (cpu != pinned_cpu)
err |= 16384;
pinned_callback_check++;
return 0;
}
static void test_pinned_timer(bool soft)
{
int key = 0;
void *map;
struct bpf_timer *timer;
__u64 flags = BPF_F_TIMER_CPU_PIN;
__u64 start_time;
if (soft) {
map = &soft_timer_pinned;
start_time = 0;
} else {
map = &abs_timer_pinned;
start_time = bpf_ktime_get_boot_ns();
flags |= BPF_F_TIMER_ABS;
}
timer = bpf_map_lookup_elem(map, &key);
if (timer) {
if (bpf_timer_init(timer, map, CLOCK_BOOTTIME) != 0)
err |= 4096;
bpf_timer_set_callback(timer, timer_cb_pinned);
pinned_cpu = bpf_get_smp_processor_id();
bpf_timer_start(timer, start_time + 1000, flags);
} else {
err |= 8192;
}
}
SEC("fentry/bpf_fentry_test4")
int BPF_PROG2(test4, int, a)
{
bpf_printk("test4");
test_pinned_timer(true);
return 0;
}
SEC("fentry/bpf_fentry_test5")
int BPF_PROG2(test5, int, a)
{
bpf_printk("test5");
test_pinned_timer(false);
return 0;
}