diff options
Diffstat (limited to 'sys/vm/vm_page.c')
| -rw-r--r-- | sys/vm/vm_page.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c index 16878604fa11..b39d665f9e0f 100644 --- a/sys/vm/vm_page.c +++ b/sys/vm/vm_page.c @@ -84,6 +84,7 @@ #include <sys/sleepqueue.h> #include <sys/sbuf.h> #include <sys/sched.h> +#include <sys/sf_buf.h> #include <sys/smp.h> #include <sys/sysctl.h> #include <sys/vmmeter.h> @@ -145,6 +146,13 @@ SYSCTL_ULONG(_vm_stats_page, OID_AUTO, nofreeq_size, CTLFLAG_RD, &nofreeq_size, 0, "Size of the nofree queue"); +#ifdef INVARIANTS +bool vm_check_pg_zero = false; +SYSCTL_BOOL(_debug, OID_AUTO, vm_check_pg_zero, CTLFLAG_RWTUN, + &vm_check_pg_zero, 0, + "verify content of freed zero-filled pages"); +#endif + /* * bogus page -- for I/O to/from partially complete buffers, * or for paging into sparsely invalid regions. @@ -4050,14 +4058,24 @@ vm_page_free_prep(vm_page_t m) */ atomic_thread_fence_acq(); -#if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP) - if (PMAP_HAS_DMAP && (m->flags & PG_ZERO) != 0) { - uint64_t *p; +#ifdef INVARIANTS + if (vm_check_pg_zero && (m->flags & PG_ZERO) != 0) { + struct sf_buf *sf; + unsigned long *p; int i; - p = (uint64_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); - for (i = 0; i < PAGE_SIZE / sizeof(uint64_t); i++, p++) - KASSERT(*p == 0, ("vm_page_free_prep %p PG_ZERO %d %jx", - m, i, (uintmax_t)*p)); + + sched_pin(); + sf = sf_buf_alloc(m, SFB_CPUPRIVATE | SFB_NOWAIT); + if (sf != NULL) { + p = (unsigned long *)sf_buf_kva(sf); + for (i = 0; i < PAGE_SIZE / sizeof(*p); i++, p++) { + KASSERT(*p == 0, + ("zerocheck failed page %p PG_ZERO %d %jx", + m, i, (uintmax_t)*p)); + } + sf_buf_free(sf); + } + sched_unpin(); } #endif if ((m->oflags & VPO_UNMANAGED) == 0) { |