bpf: Replace cant_sleep() with cant_migrate()

As already discussed in the previous change which introduced
BPF_RUN_PROG_PIN_ON_CPU() BPF only requires to disable migration to
guarantee per CPUness.

If RT substitutes the preempt disable based migration protection then the
cant_sleep() check will obviously trigger as preemption is not disabled.

Replace it by cant_migrate() which maps to cant_sleep() on a non RT kernel
and will verify that migration is disabled on a full RT kernel.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.583038889@linutronix.de
This commit is contained in:
Thomas Gleixner 2020-02-24 15:01:42 +01:00 committed by Alexei Starovoitov
parent 3c58482a38
commit 37e1d92022

View File

@ -561,7 +561,7 @@ DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
#define __BPF_PROG_RUN(prog, ctx, dfunc) ({ \
u32 ret; \
cant_sleep(); \
cant_migrate(); \
if (static_branch_unlikely(&bpf_stats_enabled_key)) { \
struct bpf_prog_stats *stats; \
u64 start = sched_clock(); \