Date: Mon, 13 May 2019 10:35:02 -0700 (PDT) From: "Rodney W. Grimes" <freebsd@gndrsh.dnsmgr.net> To: Mark Johnston <markj@freebsd.org> Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r347532 - in head: contrib/netbsd-tests/lib/libc/sys lib/libc/sys lib/libc/tests/sys sys/amd64/vmm sys/sys sys/vm usr.bin/vmstat Message-ID: <201905131735.x4DHZ2BS042282@gndrsh.dnsmgr.net> In-Reply-To: <201905131638.x4DGcmIw083437@repo.freebsd.org>
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> Author: markj > Date: Mon May 13 16:38:48 2019 > New Revision: 347532 > URL: https://svnweb.freebsd.org/changeset/base/347532 > > Log: > Provide separate accounting for user-wired pages. > > Historically we have not distinguished between kernel wirings and user > wirings for accounting purposes. User wirings (via mlock(2)) were > subject to a global limit on the number of wired pages, so if large > swaths of physical memory were wired by the kernel, as happens with > the ZFS ARC among other things, the limit could be exceeded, causing > user wirings to fail. > > The change adds a new counter, v_user_wire_count, which counts the > number of virtual pages wired by user processes via mlock(2) and > mlockall(2). Only user-wired pages are subject to the system-wide > limit which helps provide some safety against deadlocks. In > particular, while sources of kernel wirings typically support some > backpressure mechanism, there is no way to reclaim user-wired pages > shorting of killing the wiring process. The limit is exported as > vm.max_user_wired, renamed from vm.max_wired, and changed from u_int > to u_long. > > The choice to count virtual user-wired pages rather than physical > pages was done for simplicity. There are mechanisms that can cause > user-wired mappings to be destroyed while maintaining a wiring of > the backing physical page; these make it difficult to accurately > track user wirings at the physical page layer. > > The change also closes some holes which allowed user wirings to succeed > even when they would cause the system limit to be exceeded. For > instance, mmap() may now fail with ENOMEM in a process that has called > mlockall(MCL_FUTURE) if the new mapping would cause the user wiring > limit to be exceeded. > > Note that bhyve -S is subject to the user wiring limit, which defaults > to 1/3 of physical RAM. Users that wish to exceed the limit must tune > vm.max_user_wired. Because of that this should probably have a: Release Notes: Yes > Reviewed by: kib, ngie (mlock() test changes) > Tested by: pho (earlier version) > MFC after: 45 days > Sponsored by: Netflix > Differential Revision: https://reviews.freebsd.org/D19908 > > Modified: > head/contrib/netbsd-tests/lib/libc/sys/t_mlock.c > head/lib/libc/sys/mlock.2 > head/lib/libc/sys/mlockall.2 > head/lib/libc/tests/sys/mlock_helper.c > head/sys/amd64/vmm/vmm.c > head/sys/sys/vmmeter.h > head/sys/vm/vm_glue.c > head/sys/vm/vm_map.c > head/sys/vm/vm_map.h > head/sys/vm/vm_meter.c > head/sys/vm/vm_mmap.c > head/sys/vm/vm_pageout.c > head/sys/vm/vm_pageout.h > head/sys/vm/vm_unix.c > head/usr.bin/vmstat/vmstat.c > > Modified: head/contrib/netbsd-tests/lib/libc/sys/t_mlock.c > ============================================================================== > --- head/contrib/netbsd-tests/lib/libc/sys/t_mlock.c Mon May 13 15:39:54 2019 (r347531) > +++ head/contrib/netbsd-tests/lib/libc/sys/t_mlock.c Mon May 13 16:38:48 2019 (r347532) > @@ -51,7 +51,7 @@ __RCSID("$NetBSD: t_mlock.c,v 1.6 2016/08/09 12:02:44 > #define _KMEMUSER > #include <machine/vmparam.h> > > -void set_vm_max_wired(int); > +void set_vm_max_wired(u_long); > void restore_vm_max_wired(void); > #endif > > > Modified: head/lib/libc/sys/mlock.2 > ============================================================================== > --- head/lib/libc/sys/mlock.2 Mon May 13 15:39:54 2019 (r347531) > +++ head/lib/libc/sys/mlock.2 Mon May 13 16:38:48 2019 (r347532) > @@ -28,7 +28,7 @@ > .\" @(#)mlock.2 8.2 (Berkeley) 12/11/93 > .\" $FreeBSD$ > .\" > -.Dd March 20, 2018 > +.Dd May 13, 2019 > .Dt MLOCK 2 > .Os > .Sh NAME > @@ -97,13 +97,13 @@ resource limit and the > system-wide > .Dq wired pages > limit > -.Va vm.max_wired . > -.Va vm.max_wired > +.Va vm.max_user_wired . > +.Va vm.max_user_wired > applies to the system as a whole, so the amount available to a single > process at any given time is the difference between > -.Va vm.max_wired > +.Va vm.max_user_wired > and > -.Va vm.stats.vm.v_wire_count . > +.Va vm.stats.vm.v_user_wire_count . > .Pp > If > .Va security.bsd.unprivileged_mlock > @@ -124,13 +124,11 @@ will fail if: > is set to 0 and the caller is not the super-user. > .It Bq Er EINVAL > The address range given wraps around zero. > -.It Bq Er EAGAIN > -Locking the indicated range would exceed the system limit for locked memory. > .It Bq Er ENOMEM > Some portion of the indicated address range is not allocated. > There was an error faulting/mapping a page. > -Locking the indicated range would exceed the per-process limit for locked > -memory. > +Locking the indicated range would exceed the per-process or system-wide limits > +for locked memory. > .El > The > .Fn munlock > @@ -171,11 +169,11 @@ system calls first appeared in > Allocating too much wired memory can lead to a memory-allocation deadlock > which requires a reboot to recover from. > .Pp > -The per-process resource limit is a limit on the amount of virtual > -memory locked, while the system-wide limit is for the number of locked > -physical pages. > -Hence a process with two distinct locked mappings of the same physical page > -counts as 2 pages against the per-process limit and as only a single page > -in the system limit. > +The per-process and system-wide resource limits of locked memory apply > +to the amount of virtual memory locked, not the amount of locked physical > +pages. > +Hence two distinct locked mappings of the same physical page counts as > +2 pages aginst the system limit, and also against the per-process limit > +if both mappings belong to the same physical map. > .Pp > The per-process resource limit is not currently supported. > > Modified: head/lib/libc/sys/mlockall.2 > ============================================================================== > --- head/lib/libc/sys/mlockall.2 Mon May 13 15:39:54 2019 (r347531) > +++ head/lib/libc/sys/mlockall.2 Mon May 13 16:38:48 2019 (r347532) > @@ -30,7 +30,7 @@ > .\" > .\" $FreeBSD$ > .\" > -.Dd December 25, 2012 > +.Dd May 13, 2019 > .Dt MLOCKALL 2 > .Os > .Sh NAME > @@ -69,7 +69,7 @@ limited in how much they can lock down. > A single process can lock the minimum of a system-wide > .Dq wired pages > limit > -.Va vm.max_wired > +.Va vm.max_user_wired > and the per-process > .Dv RLIMIT_MEMLOCK > resource limit. > @@ -138,9 +138,9 @@ and > functions first appeared in > .Fx 5.1 . > .Sh BUGS > -The per-process resource limit is a limit on the amount of virtual > -memory locked, while the system-wide limit is for the number of locked > -physical pages. > -Hence a process with two distinct locked mappings of the same physical page > -counts as 2 pages against the per-process limit and as only a single page > -in the system limit. > +The per-process and system-wide resource limits of locked memory apply > +to the amount of virtual memory locked, not the amount of locked physical > +pages. > +Hence two distinct locked mappings of the same physical page counts as > +2 pages aginst the system limit, and also against the per-process limit > +if both mappings belong to the same physical map. > > Modified: head/lib/libc/tests/sys/mlock_helper.c > ============================================================================== > --- head/lib/libc/tests/sys/mlock_helper.c Mon May 13 15:39:54 2019 (r347531) > +++ head/lib/libc/tests/sys/mlock_helper.c Mon May 13 16:38:48 2019 (r347532) > @@ -39,16 +39,16 @@ __FBSDID("$FreeBSD$"); > #include <limits.h> > #include <stdio.h> > > -#define VM_MAX_WIRED "vm.max_wired" > +#define VM_MAX_WIRED "vm.max_user_wired" > > static void > -vm_max_wired_sysctl(int *old_value, int *new_value) > +vm_max_wired_sysctl(u_long *old_value, u_long *new_value) > { > size_t old_len; > - size_t new_len = (new_value == NULL ? 0 : sizeof(int)); > + size_t new_len = (new_value == NULL ? 0 : sizeof(*new_value)); > > if (old_value == NULL) > - printf("Setting the new value to %d\n", *new_value); > + printf("Setting the new value to %lu\n", *new_value); > else { > ATF_REQUIRE_MSG(sysctlbyname(VM_MAX_WIRED, NULL, &old_len, > new_value, new_len) == 0, > @@ -60,14 +60,14 @@ vm_max_wired_sysctl(int *old_value, int *new_value) > "sysctlbyname(%s) failed: %s", VM_MAX_WIRED, strerror(errno)); > > if (old_value != NULL) > - printf("Saved the old value (%d)\n", *old_value); > + printf("Saved the old value (%lu)\n", *old_value); > } > > void > -set_vm_max_wired(int new_value) > +set_vm_max_wired(u_long new_value) > { > FILE *fp; > - int old_value; > + u_long old_value; > > fp = fopen(VM_MAX_WIRED, "w"); > if (fp == NULL) { > @@ -78,7 +78,7 @@ set_vm_max_wired(int new_value) > > vm_max_wired_sysctl(&old_value, NULL); > > - ATF_REQUIRE_MSG(fprintf(fp, "%d", old_value) > 0, > + ATF_REQUIRE_MSG(fprintf(fp, "%lu", old_value) > 0, > "saving %s failed", VM_MAX_WIRED); > > fclose(fp); > @@ -90,7 +90,7 @@ void > restore_vm_max_wired(void) > { > FILE *fp; > - int saved_max_wired; > + u_long saved_max_wired; > > fp = fopen(VM_MAX_WIRED, "r"); > if (fp == NULL) { > @@ -98,14 +98,14 @@ restore_vm_max_wired(void) > return; > } > > - if (fscanf(fp, "%d", &saved_max_wired) != 1) { > + if (fscanf(fp, "%lu", &saved_max_wired) != 1) { > perror("fscanf failed\n"); > fclose(fp); > return; > } > > fclose(fp); > - printf("old value in %s: %d\n", VM_MAX_WIRED, saved_max_wired); > + printf("old value in %s: %lu\n", VM_MAX_WIRED, saved_max_wired); > > if (saved_max_wired == 0) /* This will cripple the test host */ > return; > > Modified: head/sys/amd64/vmm/vmm.c > ============================================================================== > --- head/sys/amd64/vmm/vmm.c Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/amd64/vmm/vmm.c Mon May 13 16:38:48 2019 (r347532) > @@ -754,7 +754,8 @@ vm_mmap_memseg(struct vm *vm, vm_paddr_t gpa, int segi > VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); > if (error != KERN_SUCCESS) { > vm_map_remove(&vm->vmspace->vm_map, gpa, gpa + len); > - return (EFAULT); > + return (error == KERN_RESOURCE_SHORTAGE ? ENOMEM : > + EFAULT); > } > } > > > Modified: head/sys/sys/vmmeter.h > ============================================================================== > --- head/sys/sys/vmmeter.h Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/sys/vmmeter.h Mon May 13 16:38:48 2019 (r347532) > @@ -153,6 +153,8 @@ extern domainset_t vm_severe_domains; > #define VM_CNT_INC(var) VM_CNT_ADD(var, 1) > #define VM_CNT_FETCH(var) counter_u64_fetch(vm_cnt.var) > > +extern u_long vm_user_wire_count; > + > static inline void > vm_wire_add(int cnt) > { > > Modified: head/sys/vm/vm_glue.c > ============================================================================== > --- head/sys/vm/vm_glue.c Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/vm/vm_glue.c Mon May 13 16:38:48 2019 (r347532) > @@ -181,21 +181,8 @@ vslock(void *addr, size_t len) > if (last < (vm_offset_t)addr || end < (vm_offset_t)addr) > return (EINVAL); > npages = atop(end - start); > - if (npages > vm_page_max_wired) > + if (npages > vm_page_max_user_wired) > return (ENOMEM); > -#if 0 > - /* > - * XXX - not yet > - * > - * The limit for transient usage of wired pages should be > - * larger than for "permanent" wired pages (mlock()). > - * > - * Also, the sysctl code, which is the only present user > - * of vslock(), does a hard loop on EAGAIN. > - */ > - if (npages + vm_wire_count() > vm_page_max_wired) > - return (EAGAIN); > -#endif > error = vm_map_wire(&curproc->p_vmspace->vm_map, start, end, > VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES); > if (error == KERN_SUCCESS) { > > Modified: head/sys/vm/vm_map.c > ============================================================================== > --- head/sys/vm/vm_map.c Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/vm/vm_map.c Mon May 13 16:38:48 2019 (r347532) > @@ -90,6 +90,7 @@ __FBSDID("$FreeBSD$"); > #include <vm/pmap.h> > #include <vm/vm_map.h> > #include <vm/vm_page.h> > +#include <vm/vm_pageout.h> > #include <vm/vm_object.h> > #include <vm/vm_pager.h> > #include <vm/vm_kern.h> > @@ -2917,12 +2918,12 @@ done: > > if (rv == KERN_SUCCESS && (!user_unwire || > (entry->eflags & MAP_ENTRY_USER_WIRED))) { > - if (user_unwire) > - entry->eflags &= ~MAP_ENTRY_USER_WIRED; > if (entry->wired_count == 1) > vm_map_entry_unwire(map, entry); > else > entry->wired_count--; > + if (user_unwire) > + entry->eflags &= ~MAP_ENTRY_USER_WIRED; > } > KASSERT((entry->eflags & MAP_ENTRY_IN_TRANSITION) != 0, > ("vm_map_unwire: in-transition flag missing %p", entry)); > @@ -2942,6 +2943,28 @@ done: > return (rv); > } > > +static void > +vm_map_wire_user_count_sub(u_long npages) > +{ > + > + atomic_subtract_long(&vm_user_wire_count, npages); > +} > + > +static bool > +vm_map_wire_user_count_add(u_long npages) > +{ > + u_long wired; > + > + wired = vm_user_wire_count; > + do { > + if (npages + wired > vm_page_max_user_wired) > + return (false); > + } while (!atomic_fcmpset_long(&vm_user_wire_count, &wired, > + npages + wired)); > + > + return (true); > +} > + > /* > * vm_map_wire_entry_failure: > * > @@ -2978,37 +3001,49 @@ vm_map_wire_entry_failure(vm_map_t map, vm_map_entry_t > entry->wired_count = -1; > } > > +int > +vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset_t end, int flags) > +{ > + int rv; > + > + vm_map_lock(map); > + rv = vm_map_wire_locked(map, start, end, flags); > + vm_map_unlock(map); > + return (rv); > +} > + > + > /* > - * vm_map_wire: > + * vm_map_wire_locked: > * > - * Implements both kernel and user wiring. > + * Implements both kernel and user wiring. Returns with the map locked, > + * the map lock may be dropped. > */ > int > -vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset_t end, > - int flags) > +vm_map_wire_locked(vm_map_t map, vm_offset_t start, vm_offset_t end, int flags) > { > vm_map_entry_t entry, first_entry, tmp_entry; > vm_offset_t faddr, saved_end, saved_start; > - unsigned int last_timestamp; > + u_long npages; > + u_int last_timestamp; > int rv; > boolean_t need_wakeup, result, user_wire; > vm_prot_t prot; > > + VM_MAP_ASSERT_LOCKED(map); > + > if (start == end) > return (KERN_SUCCESS); > prot = 0; > if (flags & VM_MAP_WIRE_WRITE) > prot |= VM_PROT_WRITE; > user_wire = (flags & VM_MAP_WIRE_USER) ? TRUE : FALSE; > - vm_map_lock(map); > VM_MAP_RANGE_CHECK(map, start, end); > if (!vm_map_lookup_entry(map, start, &first_entry)) { > if (flags & VM_MAP_WIRE_HOLESOK) > first_entry = first_entry->next; > - else { > - vm_map_unlock(map); > + else > return (KERN_INVALID_ADDRESS); > - } > } > last_timestamp = map->timestamp; > entry = first_entry; > @@ -3042,7 +3077,6 @@ vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset > /* > * first_entry has been deleted. > */ > - vm_map_unlock(map); > return (KERN_INVALID_ADDRESS); > } > end = saved_start; > @@ -3082,13 +3116,22 @@ vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset > } > if (entry->wired_count == 0) { > entry->wired_count++; > - saved_start = entry->start; > - saved_end = entry->end; > > + npages = atop(entry->end - entry->start); > + if (user_wire && !vm_map_wire_user_count_add(npages)) { > + vm_map_wire_entry_failure(map, entry, > + entry->start); > + end = entry->end; > + rv = KERN_RESOURCE_SHORTAGE; > + goto done; > + } > + > /* > * Release the map lock, relying on the in-transition > * mark. Mark the map busy for fork. > */ > + saved_start = entry->start; > + saved_end = entry->end; > vm_map_busy(map); > vm_map_unlock(map); > > @@ -3136,6 +3179,8 @@ vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset > last_timestamp = map->timestamp; > if (rv != KERN_SUCCESS) { > vm_map_wire_entry_failure(map, entry, faddr); > + if (user_wire) > + vm_map_wire_user_count_sub(npages); > end = entry->end; > goto done; > } > @@ -3201,9 +3246,12 @@ done: > * Undo the wiring. Wiring succeeded on this entry > * but failed on a later entry. > */ > - if (entry->wired_count == 1) > + if (entry->wired_count == 1) { > vm_map_entry_unwire(map, entry); > - else > + if (user_wire) > + vm_map_wire_user_count_sub( > + atop(entry->end - entry->start)); > + } else > entry->wired_count--; > } > next_entry_done: > @@ -3220,7 +3268,6 @@ done: > } > vm_map_simplify_entry(map, entry); > } > - vm_map_unlock(map); > if (need_wakeup) > vm_map_wakeup(map); > return (rv); > @@ -3338,13 +3385,18 @@ vm_map_sync( > static void > vm_map_entry_unwire(vm_map_t map, vm_map_entry_t entry) > { > + vm_size_t size; > > VM_MAP_ASSERT_LOCKED(map); > KASSERT(entry->wired_count > 0, > ("vm_map_entry_unwire: entry %p isn't wired", entry)); > + > + size = entry->end - entry->start; > + if ((entry->eflags & MAP_ENTRY_USER_WIRED) != 0) > + vm_map_wire_user_count_sub(atop(size)); > pmap_unwire(map->pmap, entry->start, entry->end); > - vm_object_unwire(entry->object.vm_object, entry->offset, entry->end - > - entry->start, PQ_ACTIVE); > + vm_object_unwire(entry->object.vm_object, entry->offset, size, > + PQ_ACTIVE); > entry->wired_count = 0; > } > > @@ -4311,12 +4363,11 @@ retry: > * Heed the MAP_WIREFUTURE flag if it was set for this process. > */ > if (rv == KERN_SUCCESS && (map->flags & MAP_WIREFUTURE) != 0) { > - vm_map_unlock(map); > - vm_map_wire(map, grow_start, grow_start + grow_amount, > + rv = vm_map_wire_locked(map, grow_start, > + grow_start + grow_amount, > VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); > - vm_map_lock_read(map); > - } else > - vm_map_lock_downgrade(map); > + } > + vm_map_lock_downgrade(map); > > out: > #ifdef RACCT > > Modified: head/sys/vm/vm_map.h > ============================================================================== > --- head/sys/vm/vm_map.h Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/vm/vm_map.h Mon May 13 16:38:48 2019 (r347532) > @@ -422,7 +422,8 @@ int vm_map_madvise (vm_map_t, vm_offset_t, vm_offset_t > int vm_map_stack (vm_map_t, vm_offset_t, vm_size_t, vm_prot_t, vm_prot_t, int); > int vm_map_unwire(vm_map_t map, vm_offset_t start, vm_offset_t end, > int flags); > -int vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset_t end, > +int vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset_t end, int flags); > +int vm_map_wire_locked(vm_map_t map, vm_offset_t start, vm_offset_t end, > int flags); > long vmspace_swap_count(struct vmspace *vmspace); > void vm_map_entry_set_vnode_text(vm_map_entry_t entry, bool add); > > Modified: head/sys/vm/vm_meter.c > ============================================================================== > --- head/sys/vm/vm_meter.c Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/vm/vm_meter.c Mon May 13 16:38:48 2019 (r347532) > @@ -97,6 +97,8 @@ struct vmmeter __read_mostly vm_cnt = { > .v_wire_count = EARLY_COUNTER, > }; > > +u_long __exclusive_cache_line vm_user_wire_count; > + > static void > vmcounter_startup(void) > { > @@ -394,6 +396,8 @@ sysctl_handle_vmstat_proc(SYSCTL_HANDLER_ARGS) > > #define VM_STATS_UINT(var, descr) \ > SYSCTL_UINT(_vm_stats_vm, OID_AUTO, var, CTLFLAG_RD, &vm_cnt.var, 0, descr) > +#define VM_STATS_ULONG(var, descr) \ > + SYSCTL_ULONG(_vm_stats_vm, OID_AUTO, var, CTLFLAG_RD, &vm_cnt.var, 0, descr) > > VM_STATS_UINT(v_page_size, "Page size in bytes"); > VM_STATS_UINT(v_page_count, "Total number of pages in system"); > @@ -410,6 +414,9 @@ VM_STATS_PROC(v_laundry_count, "Pages eligible for lau > VM_STATS_UINT(v_pageout_free_min, "Min pages reserved for kernel"); > VM_STATS_UINT(v_interrupt_free_min, "Reserved pages for interrupt code"); > VM_STATS_UINT(v_free_severe, "Severe page depletion point"); > + > +SYSCTL_ULONG(_vm_stats_vm, OID_AUTO, v_user_wire_count, CTLFLAG_RD, > + &vm_user_wire_count, 0, "User-wired virtual memory"); > > #ifdef COMPAT_FREEBSD11 > /* > > Modified: head/sys/vm/vm_mmap.c > ============================================================================== > --- head/sys/vm/vm_mmap.c Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/vm/vm_mmap.c Mon May 13 16:38:48 2019 (r347532) > @@ -1003,7 +1003,7 @@ kern_mlock(struct proc *proc, struct ucred *cred, uint > if (last < addr || end < addr) > return (EINVAL); > npages = atop(end - start); > - if (npages > vm_page_max_wired) > + if (npages > vm_page_max_user_wired) > return (ENOMEM); > map = &proc->p_vmspace->vm_map; > PROC_LOCK(proc); > @@ -1013,8 +1013,6 @@ kern_mlock(struct proc *proc, struct ucred *cred, uint > return (ENOMEM); > } > PROC_UNLOCK(proc); > - if (npages + vm_wire_count() > vm_page_max_wired) > - return (EAGAIN); > #ifdef RACCT > if (racct_enable) { > PROC_LOCK(proc); > @@ -1091,7 +1089,12 @@ sys_mlockall(struct thread *td, struct mlockall_args * > */ > error = vm_map_wire(map, vm_map_min(map), vm_map_max(map), > VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); > - error = (error == KERN_SUCCESS ? 0 : EAGAIN); > + if (error == KERN_SUCCESS) > + error = 0; > + else if (error == KERN_RESOURCE_SHORTAGE) > + error = ENOMEM; > + else > + error = EAGAIN; > } > #ifdef RACCT > if (racct_enable && error != KERN_SUCCESS) { > @@ -1558,10 +1561,16 @@ vm_mmap_object(vm_map_t map, vm_offset_t *addr, vm_siz > * If the process has requested that all future mappings > * be wired, then heed this. > */ > - if (map->flags & MAP_WIREFUTURE) { > - vm_map_wire(map, *addr, *addr + size, > - VM_MAP_WIRE_USER | ((flags & MAP_STACK) ? > - VM_MAP_WIRE_HOLESOK : VM_MAP_WIRE_NOHOLES)); > + if ((map->flags & MAP_WIREFUTURE) != 0) { > + vm_map_lock(map); > + if ((map->flags & MAP_WIREFUTURE) != 0) > + rv = vm_map_wire_locked(map, *addr, > + *addr + size, VM_MAP_WIRE_USER | > + ((flags & MAP_STACK) ? VM_MAP_WIRE_HOLESOK : > + VM_MAP_WIRE_NOHOLES)); > + if (rv != KERN_SUCCESS) > + (void)vm_map_delete(map, *addr, *addr + size); > + vm_map_unlock(map); > } > } > return (vm_mmap_to_errno(rv)); > > Modified: head/sys/vm/vm_pageout.c > ============================================================================== > --- head/sys/vm/vm_pageout.c Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/vm/vm_pageout.c Mon May 13 16:38:48 2019 (r347532) > @@ -194,9 +194,10 @@ SYSCTL_UINT(_vm, OID_AUTO, background_launder_max, CTL > > int vm_pageout_page_count = 32; > > -int vm_page_max_wired; /* XXX max # of wired pages system-wide */ > -SYSCTL_INT(_vm, OID_AUTO, max_wired, > - CTLFLAG_RW, &vm_page_max_wired, 0, "System-wide limit to wired page count"); > +u_long vm_page_max_user_wired; > +SYSCTL_ULONG(_vm, OID_AUTO, max_user_wired, CTLFLAG_RW, > + &vm_page_max_user_wired, 0, > + "system-wide limit to user-wired page count"); > > static u_int isqrt(u_int num); > static int vm_pageout_launder(struct vm_domain *vmd, int launder, > @@ -2041,8 +2042,8 @@ vm_pageout_init(void) > if (vm_pageout_update_period == 0) > vm_pageout_update_period = 600; > > - if (vm_page_max_wired == 0) > - vm_page_max_wired = freecount / 3; > + if (vm_page_max_user_wired == 0) > + vm_page_max_user_wired = freecount / 3; > } > > /* > > Modified: head/sys/vm/vm_pageout.h > ============================================================================== > --- head/sys/vm/vm_pageout.h Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/vm/vm_pageout.h Mon May 13 16:38:48 2019 (r347532) > @@ -75,7 +75,7 @@ > * Exported data structures. > */ > > -extern int vm_page_max_wired; > +extern u_long vm_page_max_user_wired; > extern int vm_pageout_page_count; > > #define VM_OOM_MEM 1 > > Modified: head/sys/vm/vm_unix.c > ============================================================================== > --- head/sys/vm/vm_unix.c Mon May 13 15:39:54 2019 (r347531) > +++ head/sys/vm/vm_unix.c Mon May 13 16:38:48 2019 (r347532) > @@ -95,13 +95,11 @@ kern_break(struct thread *td, uintptr_t *addr) > rlim_t datalim, lmemlim, vmemlim; > int prot, rv; > int error = 0; > - boolean_t do_map_wirefuture; > > datalim = lim_cur(td, RLIMIT_DATA); > lmemlim = lim_cur(td, RLIMIT_MEMLOCK); > vmemlim = lim_cur(td, RLIMIT_VMEM); > > - do_map_wirefuture = FALSE; > new = round_page(*addr); > vm_map_lock(map); > > @@ -184,7 +182,14 @@ kern_break(struct thread *td, uintptr_t *addr) > if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32)) > prot |= VM_PROT_EXECUTE; > #endif > - rv = vm_map_insert(map, NULL, 0, old, new, prot, VM_PROT_ALL, 0); > + rv = vm_map_insert(map, NULL, 0, old, new, prot, VM_PROT_ALL, > + 0); > + if (rv == KERN_SUCCESS && (map->flags & MAP_WIREFUTURE) != 0) { > + rv = vm_map_wire_locked(map, old, new, > + VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); > + if (rv != KERN_SUCCESS) > + vm_map_delete(map, old, new); > + } > if (rv != KERN_SUCCESS) { > #ifdef RACCT > if (racct_enable) { > @@ -205,17 +210,6 @@ kern_break(struct thread *td, uintptr_t *addr) > goto done; > } > vm->vm_dsize += btoc(new - old); > - /* > - * Handle the MAP_WIREFUTURE case for legacy applications, > - * by marking the newly mapped range of pages as wired. > - * We are not required to perform a corresponding > - * vm_map_unwire() before vm_map_delete() below, as > - * it will forcibly unwire the pages in the range. > - * > - * XXX If the pages cannot be wired, no error is returned. > - */ > - if ((map->flags & MAP_WIREFUTURE) == MAP_WIREFUTURE) > - do_map_wirefuture = TRUE; > } else if (new < old) { > rv = vm_map_delete(map, new, old); > if (rv != KERN_SUCCESS) { > @@ -238,10 +232,6 @@ kern_break(struct thread *td, uintptr_t *addr) > } > done: > vm_map_unlock(map); > - > - if (do_map_wirefuture) > - (void) vm_map_wire(map, old, new, > - VM_MAP_WIRE_USER|VM_MAP_WIRE_NOHOLES); > > if (error == 0) > *addr = new; > > Modified: head/usr.bin/vmstat/vmstat.c > ============================================================================== > --- head/usr.bin/vmstat/vmstat.c Mon May 13 15:39:54 2019 (r347531) > +++ head/usr.bin/vmstat/vmstat.c Mon May 13 16:38:48 2019 (r347532) > @@ -156,6 +156,7 @@ static struct __vmmeter { > u_int v_free_min; > u_int v_free_count; > u_int v_wire_count; > + u_long v_user_wire_count; > u_int v_active_count; > u_int v_inactive_target; > u_int v_inactive_count; > @@ -566,6 +567,7 @@ fill_vmmeter(struct __vmmeter *vmmp) > GET_VM_STATS(vm, v_free_min); > GET_VM_STATS(vm, v_free_count); > GET_VM_STATS(vm, v_wire_count); > + GET_VM_STATS(vm, v_user_wire_count); > GET_VM_STATS(vm, v_active_count); > GET_VM_STATS(vm, v_inactive_target); > GET_VM_STATS(vm, v_inactive_count); > @@ -1057,6 +1059,8 @@ dosum(void) > sum.v_laundry_count); > xo_emit("{:wired-pages/%9u} {N:pages wired down}\n", > sum.v_wire_count); > + xo_emit("{:virtual-user-wired-pages/%9lu} {N:virtual user pages wired " > + "down}\n", sum.v_user_wire_count); > xo_emit("{:free-pages/%9u} {N:pages free}\n", > sum.v_free_count); > xo_emit("{:bytes-per-page/%9u} {N:bytes per page}\n", sum.v_page_size); > > -- Rod Grimes rgrimes@freebsd.org
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