diff options
Diffstat (limited to 'sys/vm/vm_page.c')
| -rw-r--r-- | sys/vm/vm_page.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c index 7b4b57c..53ffc72 100644 --- a/sys/vm/vm_page.c +++ b/sys/vm/vm_page.c @@ -602,9 +602,13 @@ vm_page_trysbusy(vm_page_t m) { u_int x; - x = m->busy_lock; - return ((x & VPB_BIT_SHARED) != 0 && - atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER)); + for (;;) { + x = m->busy_lock; + if ((x & VPB_BIT_SHARED) == 0) + return (0); + if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER)) + return (1); + } } /* |
