From 8c3570e33954d26675ec6fd224ede02763dfbd1d Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 20 Feb 2020 11:38:28 +0100 Subject: rcu_queue: add QSLIST functions QSLIST is the only family of lists for which we do not have RCU-friendly accessors, add them. Signed-off-by: Paolo Bonzini Reviewed-by: Stefan Hajnoczi Message-id: 20200220103828.24525-1-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi --- include/qemu/rcu_queue.h | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) (limited to 'include/qemu/rcu_queue.h') diff --git a/include/qemu/rcu_queue.h b/include/qemu/rcu_queue.h index 2d386f303e..558961cc27 100644 --- a/include/qemu/rcu_queue.h +++ b/include/qemu/rcu_queue.h @@ -262,6 +262,53 @@ extern "C" { (var) && ((next) = atomic_rcu_read(&(var)->field.tqe_next), 1); \ (var) = (next)) +/* + * RCU singly-linked list + */ + +/* Singly-linked list access methods */ +#define QSLIST_EMPTY_RCU(head) (atomic_read(&(head)->slh_first) == NULL) +#define QSLIST_FIRST_RCU(head) atomic_rcu_read(&(head)->slh_first) +#define QSLIST_NEXT_RCU(elm, field) atomic_rcu_read(&(elm)->field.sle_next) + +/* Singly-linked list functions */ +#define QSLIST_INSERT_HEAD_RCU(head, elm, field) do { \ + (elm)->field.sle_next = (head)->slh_first; \ + atomic_rcu_set(&(head)->slh_first, (elm)); \ +} while (/*CONSTCOND*/0) + +#define QSLIST_INSERT_AFTER_RCU(head, listelm, elm, field) do { \ + (elm)->field.sle_next = (listelm)->field.sle_next; \ + atomic_rcu_set(&(listelm)->field.sle_next, (elm)); \ +} while (/*CONSTCOND*/0) + +#define QSLIST_REMOVE_HEAD_RCU(head, field) do { \ + atomic_set(&(head)->slh_first, (head)->slh_first->field.sle_next); \ +} while (/*CONSTCOND*/0) + +#define QSLIST_REMOVE_RCU(head, elm, type, field) do { \ + if ((head)->slh_first == (elm)) { \ + QSLIST_REMOVE_HEAD_RCU((head), field); \ + } else { \ + struct type *curr = (head)->slh_first; \ + while (curr->field.sle_next != (elm)) { \ + curr = curr->field.sle_next; \ + } \ + atomic_set(&curr->field.sle_next, \ + curr->field.sle_next->field.sle_next); \ + } \ +} while (/*CONSTCOND*/0) + +#define QSLIST_FOREACH_RCU(var, head, field) \ + for ((var) = atomic_rcu_read(&(head)->slh_first); \ + (var); \ + (var) = atomic_rcu_read(&(var)->field.sle_next)) + +#define QSLIST_FOREACH_SAFE_RCU(var, head, field, next) \ + for ((var) = atomic_rcu_read(&(head)->slh_first); \ + (var) && ((next) = atomic_rcu_read(&(var)->field.sle_next), 1); \ + (var) = (next)) + #ifdef __cplusplus } #endif -- cgit 1.4.1