The branch stable/13 has been updated by markj:
URL:
https://cgit.FreeBSD.org/src/commit/?id=61c3b6832d3bcd10430b8badac55e0d4fb16db20
commit 61c3b6832d3bcd10430b8badac55e0d4fb16db20
Author: Mark Johnston <ma...@freebsd.org>
AuthorDate: 2021-11-24 18:42:32 +0000
Commit: Mark Johnston <ma...@freebsd.org>
CommitDate: 2021-12-08 13:39:47 +0000
vm_fault: Move nera into faultstate
This makes it easier to factor out pieces of vm_fault(). No functional
change intended.
Obtained from: jeff (object_concurrency patches)
Reviewed by: kib
(cherry picked from commit 45c09a74d681cfcad0a556b753cd56f6084ace46)
---
sys/vm/vm_fault.c | 62 ++++++++++++++++++++++++++++++-------------------------
1 file changed, 34 insertions(+), 28 deletions(-)
diff --git a/sys/vm/vm_fault.c b/sys/vm/vm_fault.c
index 646f9ddb9017..d85f4b524b72 100644
--- a/sys/vm/vm_fault.c
+++ b/sys/vm/vm_fault.c
@@ -125,9 +125,12 @@ struct faultstate {
vm_prot_t fault_type;
vm_prot_t prot;
int fault_flags;
+ boolean_t wired;
+
+ /* Control state. */
struct timeval oom_start_time;
bool oom_started;
- boolean_t wired;
+ int nera;
/* Page reference for cow. */
vm_page_t m_cow;
@@ -1180,7 +1183,7 @@ vm_fault_allocate(struct faultstate *fs)
* pages at the same time.
*/
static int
-vm_fault_getpages(struct faultstate *fs, int nera, int *behindp, int *aheadp)
+vm_fault_getpages(struct faultstate *fs, int *behindp, int *aheadp)
{
vm_offset_t e_end, e_start;
int ahead, behind, cluster_offset, rv;
@@ -1198,6 +1201,20 @@ vm_fault_getpages(struct faultstate *fs, int nera, int
*behindp, int *aheadp)
e_end = fs->entry->end;
behavior = vm_map_entry_behavior(fs->entry);
+ /*
+ * If the pager for the current object might have
+ * the page, then determine the number of additional
+ * pages to read and potentially reprioritize
+ * previously read pages for earlier reclamation.
+ * These operations should only be performed once per
+ * page fault. Even if the current pager doesn't
+ * have the page, the number of additional pages to
+ * read will apply to subsequent objects in the
+ * shadow chain.
+ */
+ if (fs->nera == -1 && !P_KILLED(curproc))
+ fs->nera = vm_fault_readahead(fs);
+
/*
* Release the map lock before locking the vnode or
* sleeping in the pager. (If the current object has
@@ -1217,15 +1234,15 @@ vm_fault_getpages(struct faultstate *fs, int nera, int
*behindp, int *aheadp)
* Page in the requested page and hint the pager,
* that it may bring up surrounding pages.
*/
- if (nera == -1 || behavior == MAP_ENTRY_BEHAV_RANDOM ||
+ if (fs->nera == -1 || behavior == MAP_ENTRY_BEHAV_RANDOM ||
P_KILLED(curproc)) {
behind = 0;
ahead = 0;
} else {
/* Is this a sequential fault? */
- if (nera > 0) {
+ if (fs->nera > 0) {
behind = 0;
- ahead = nera;
+ ahead = fs->nera;
} else {
/*
* Request a cluster of pages that is
@@ -1257,8 +1274,14 @@ vm_fault_getpages(struct faultstate *fs, int nera, int
*behindp, int *aheadp)
* outside the range of the pager, clean up and return
* an error.
*/
- if (rv == VM_PAGER_ERROR || rv == VM_PAGER_BAD)
+ if (rv == VM_PAGER_ERROR || rv == VM_PAGER_BAD) {
+ VM_OBJECT_WLOCK(fs->object);
+ fault_page_free(&fs->m);
+ unlock_and_deallocate(fs);
return (KERN_OUT_OF_BOUNDS);
+ }
+ KASSERT(rv == VM_PAGER_FAIL,
+ ("%s: unepxected pager error %d", __func__, rv));
return (KERN_NOT_RECEIVER);
}
@@ -1303,7 +1326,7 @@ vm_fault(vm_map_t map, vm_offset_t vaddr, vm_prot_t
fault_type,
{
struct faultstate fs;
int ahead, behind, faultcount;
- int nera, result, rv;
+ int result, rv;
bool dead, hardfault;
VM_CNT_INC(v_vm_faults);
@@ -1318,8 +1341,8 @@ vm_fault(vm_map_t map, vm_offset_t vaddr, vm_prot_t
fault_type,
fs.map = map;
fs.lookup_still_valid = false;
fs.oom_started = false;
+ fs.nera = -1;
faultcount = 0;
- nera = -1;
hardfault = false;
RetryFault:
@@ -1486,21 +1509,7 @@ RetryFault:
*/
VM_OBJECT_WUNLOCK(fs.object);
- /*
- * If the pager for the current object might have
- * the page, then determine the number of additional
- * pages to read and potentially reprioritize
- * previously read pages for earlier reclamation.
- * These operations should only be performed once per
- * page fault. Even if the current pager doesn't
- * have the page, the number of additional pages to
- * read will apply to subsequent objects in the
- * shadow chain.
- */
- if (nera == -1 && !P_KILLED(curproc))
- nera = vm_fault_readahead(&fs);
-
- rv = vm_fault_getpages(&fs, nera, &behind, &ahead);
+ rv = vm_fault_getpages(&fs, &behind, &ahead);
if (rv == KERN_SUCCESS) {
faultcount = behind + 1 + ahead;
hardfault = true;
@@ -1508,12 +1517,9 @@ RetryFault:
}
if (rv == KERN_RESOURCE_SHORTAGE)
goto RetryFault;
- VM_OBJECT_WLOCK(fs.object);
- if (rv == KERN_OUT_OF_BOUNDS) {
- fault_page_free(&fs.m);
- unlock_and_deallocate(&fs);
+ if (rv == KERN_OUT_OF_BOUNDS)
return (rv);
- }
+ VM_OBJECT_WLOCK(fs.object);
}
/*
