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| author | dillon <dillon@FreeBSD.org> | 2000-05-29 22:40:54 +0000 |
|---|---|---|
| committer | dillon <dillon@FreeBSD.org> | 2000-05-29 22:40:54 +0000 |
| commit | 82627e96a026e438a7251b0e5dc0a5322435693c (patch) | |
| tree | 30efad495e652bce5e17011dd662ffce150ecd07 /sys/amd64 | |
| parent | 2e7f60e876b44bc7a2762fa018f17c30864bc19d (diff) | |
| download | FreeBSD-src-82627e96a026e438a7251b0e5dc0a5322435693c.zip FreeBSD-src-82627e96a026e438a7251b0e5dc0a5322435693c.tar.gz | |
This is a cleanup patch to Peter's new OBJT_PHYS VM object type
and sysv shared memory support for it. It implements a new
PG_UNMANAGED flag that has slightly different characteristics
from PG_FICTICIOUS.
A new sysctl, kern.ipc.shm_use_phys has been added to enable the
use of physically-backed sysv shared memory rather then swap-backed.
Physically backed shm segments are not tracked with PV entries,
allowing programs which use a large shm segment as a rendezvous
point to operate without eating an insane amount of KVM in the
PV entry management. Read: Oracle.
Peter's OBJT_PHYS object will also allow us to eventually implement
page-table sharing and/or 4MB physical page support for such segments.
We're half way there.
Diffstat (limited to 'sys/amd64')
| -rw-r--r-- | sys/amd64/amd64/pmap.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c index 5e3d6b5..7b27446 100644 --- a/sys/amd64/amd64/pmap.c +++ b/sys/amd64/amd64/pmap.c @@ -2095,7 +2095,8 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, * raise IPL while manipulating pv_table since pmap_enter can be * called at interrupt time. */ - if (pmap_initialized && (m->flags & PG_FICTITIOUS) == 0) { + if (pmap_initialized && + (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { pmap_insert_entry(pmap, va, mpte, m); pa |= PG_MANAGED; } @@ -2223,7 +2224,8 @@ retry: * raise IPL while manipulating pv_table since pmap_enter can be * called at interrupt time. */ - pmap_insert_entry(pmap, va, mpte, m); + if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) + pmap_insert_entry(pmap, va, mpte, m); /* * Increment counters @@ -2235,7 +2237,10 @@ retry: /* * Now validate mapping with RO protection */ - *pte = pa | PG_V | PG_U | PG_MANAGED; + if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) + *pte = pa | PG_V | PG_U; + else + *pte = pa | PG_V | PG_U | PG_MANAGED; return mpte; } |
