CONFIG_PREEMPT is a preemtion model the so called "Low-Latency Desktop". A different preemption model is PREEMPT_RT the so called "Real-Time". Both implement preemption in kernel and set CONFIG_PREEMPTION. There is also the so called "LAZY PREEMPT" which the "Scheduler controlled preemption model". Here we have also preemption in the kernel the rules are slightly different.
Therefore the testsuite should not check for CONFIG_PREEMPT (as one model) but for CONFIG_PREEMPTION to figure out if preemption in the kernel is possible.
Signed-off-by: Sebastian Andrzej Siewior bigeasy@linutronix.de --- tools/testing/selftests/bpf/map_tests/task_storage_map.c | 4 ++-- tools/testing/selftests/bpf/prog_tests/task_local_storage.c | 2 +- .../testing/selftests/bpf/progs/read_bpf_task_storage_busy.c | 4 ++-- tools/testing/selftests/bpf/progs/task_storage_nodeadlock.c | 4 ++-- 4 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/tools/testing/selftests/bpf/map_tests/task_storage_map.c b/tools/testing/selftests/bpf/map_tests/task_storage_map.c index 7d050364efca1..5fd7c923544c3 100644 --- a/tools/testing/selftests/bpf/map_tests/task_storage_map.c +++ b/tools/testing/selftests/bpf/map_tests/task_storage_map.c @@ -77,8 +77,8 @@ void test_task_storage_map_stress_lookup(void) CHECK(err, "open_and_load", "error %d\n", err);
/* Only for a fully preemptible kernel */ - if (!skel->kconfig->CONFIG_PREEMPT) { - printf("%s SKIP (no CONFIG_PREEMPT)\n", __func__); + if (!skel->kconfig->CONFIG_PREEMPTION) { + printf("%s SKIP (no CONFIG_PREEMPTION)\n", __func__); read_bpf_task_storage_busy__destroy(skel); skips++; return; diff --git a/tools/testing/selftests/bpf/prog_tests/task_local_storage.c b/tools/testing/selftests/bpf/prog_tests/task_local_storage.c index c33c05161a9ea..acaeebf83f3ee 100644 --- a/tools/testing/selftests/bpf/prog_tests/task_local_storage.c +++ b/tools/testing/selftests/bpf/prog_tests/task_local_storage.c @@ -189,7 +189,7 @@ static void test_nodeadlock(void) /* Unnecessary recursion and deadlock detection are reproducible * in the preemptible kernel. */ - if (!skel->kconfig->CONFIG_PREEMPT) { + if (!skel->kconfig->CONFIG_PREEMPTION) { test__skip(); goto done; } diff --git a/tools/testing/selftests/bpf/progs/read_bpf_task_storage_busy.c b/tools/testing/selftests/bpf/progs/read_bpf_task_storage_busy.c index 76556e0b42b24..69da05bb6c63e 100644 --- a/tools/testing/selftests/bpf/progs/read_bpf_task_storage_busy.c +++ b/tools/testing/selftests/bpf/progs/read_bpf_task_storage_busy.c @@ -4,7 +4,7 @@ #include <bpf/bpf_helpers.h> #include <bpf/bpf_tracing.h>
-extern bool CONFIG_PREEMPT __kconfig __weak; +extern bool CONFIG_PREEMPTION __kconfig __weak; extern const int bpf_task_storage_busy __ksym;
char _license[] SEC("license") = "GPL"; @@ -24,7 +24,7 @@ int BPF_PROG(read_bpf_task_storage_busy) { int *value;
- if (!CONFIG_PREEMPT) + if (!CONFIG_PREEMPTION) return 0;
if (bpf_get_current_pid_tgid() >> 32 != pid) diff --git a/tools/testing/selftests/bpf/progs/task_storage_nodeadlock.c b/tools/testing/selftests/bpf/progs/task_storage_nodeadlock.c index ea2dbb80f7b3e..986829aaf73a6 100644 --- a/tools/testing/selftests/bpf/progs/task_storage_nodeadlock.c +++ b/tools/testing/selftests/bpf/progs/task_storage_nodeadlock.c @@ -10,7 +10,7 @@ char _license[] SEC("license") = "GPL"; #define EBUSY 16 #endif
-extern bool CONFIG_PREEMPT __kconfig __weak; +extern bool CONFIG_PREEMPTION __kconfig __weak; int nr_get_errs = 0; int nr_del_errs = 0;
@@ -29,7 +29,7 @@ int BPF_PROG(socket_post_create, struct socket *sock, int family, int type, int ret, zero = 0; int *value;
- if (!CONFIG_PREEMPT) + if (!CONFIG_PREEMPTION) return 0;
task = bpf_get_current_task_btf();
Hello:
This patch was applied to bpf/bpf.git (master) by Alexei Starovoitov ast@kernel.org:
On Tue, 19 Nov 2024 17:18:19 +0100 you wrote:
CONFIG_PREEMPT is a preemtion model the so called "Low-Latency Desktop". A different preemption model is PREEMPT_RT the so called "Real-Time". Both implement preemption in kernel and set CONFIG_PREEMPTION. There is also the so called "LAZY PREEMPT" which the "Scheduler controlled preemption model". Here we have also preemption in the kernel the rules are slightly different.
[...]
Here is the summary with links: - [bpf] selftests/bpf: Check for PREEMPTION instead of PREEMPT https://git.kernel.org/bpf/bpf/c/6b64128a74eb
You are awesome, thank you!
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