On Sat, Oct 05, 2024 at 02:56:26PM -0400, Mathieu Desnoyers wrote:
On 2024-10-05 18:07, Peter Zijlstra wrote:
On Sat, Oct 05, 2024 at 06:04:44PM +0200, Peter Zijlstra wrote:
On Fri, Oct 04, 2024 at 02:27:33PM -0400, Mathieu Desnoyers wrote:
+void hp_scan(struct hp_slot __percpu *percpu_slots, void *addr,
+ void (*retire_cb)(int cpu, struct hp_slot *slot, void *addr))
+{
+ int cpu;
+
+ /*
+ * Store A precedes hp_scan(): it unpublishes addr (sets it to
+ * NULL or to a different value), and thus hides it from hazard
+ * pointer readers.
+ */
This should probably assert we're in a preemptible context. Otherwise
people will start using this in non-preemptible context and then we get
to unfuck things later.
Something like this ?
+ /* Should only be called from preemptible context. */
+ WARN_ON_ONCE(in_atomic());
lockdep_assert_preemption_enabled();
that also checks local IRQ state IIRC.