On Tue, Nov 11, 2025 at 6:33 AM Saket Kumar Bhaskar <[email protected]> wrote: > > On Thu, Nov 06, 2025 at 09:15:39AM -0800, Alexei Starovoitov wrote: > > On Wed, Nov 5, 2025 at 9:26 PM Saket Kumar Bhaskar <[email protected]> > > wrote: > > > > > > Since commit 31158ad02ddb ("rqspinlock: Add deadlock detection and > > > recovery") > > > the updated path on re-entrancy now reports deadlock via > > > -EDEADLK instead of the previous -EBUSY. > > > > > > The selftest is updated to align with expected errno > > > with the kernel’s current behavior. > > > > > > Signed-off-by: Saket Kumar Bhaskar <[email protected]> > > > --- > > > tools/testing/selftests/bpf/prog_tests/htab_update.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/tools/testing/selftests/bpf/prog_tests/htab_update.c > > > b/tools/testing/selftests/bpf/prog_tests/htab_update.c > > > index 2bc85f4814f4..98d52bb1446f 100644 > > > --- a/tools/testing/selftests/bpf/prog_tests/htab_update.c > > > +++ b/tools/testing/selftests/bpf/prog_tests/htab_update.c > > > @@ -40,7 +40,7 @@ static void test_reenter_update(void) > > > if (!ASSERT_OK(err, "add element")) > > > goto out; > > > > > > - ASSERT_EQ(skel->bss->update_err, -EBUSY, "no reentrancy"); > > > + ASSERT_EQ(skel->bss->update_err, -EDEADLK, "no reentrancy"); > > > > Makes sense, but looks like the test was broken for quite some time. > > It fails with > > /* lookup_elem_raw() may be inlined and find_kernel_btf_id() > > will return -ESRCH */ > > bpf_program__set_autoload(skel->progs.lookup_elem_raw, true); > > err = htab_update__load(skel); > > if (!ASSERT_TRUE(!err || err == -ESRCH, "htab_update__load") || err) > > > > before reaching deadlk check. > > Pls make it more robust. > > __pcpu_freelist_pop() might be better alternative then lookup_elem_raw(). > > > > pw-bot: cr > > Hi Alexei, > > I tried for __pcpu_freelist_pop, looks like it is not good candidate to > attach fentry for, as it is non traceable: > > trace_kprobe: Could not probe notrace function __pcpu_freelist_pop > > I wasn't able to find any other function for this.
alloc_htab_elem() is not inlined for me. bpf_obj_free_fields() would be another option.
