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beb3c3a9c5
freebsd-dev/sys
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Alan Cox beb3c3a9c5 Retire VM_PROT_READ_IS_EXEC. It was intended to be a micro-optimization, 
but I see no benefit from it today.

VM_PROT_READ_IS_EXEC was only intended for use on processors that do not
distinguish between read and execute permission.  On an mmap(2) or
mprotect(2), it automatically added execute permission if the caller
specified permissions included read permission.  The hope was that this
would reduce the number of vm map entries needed to implement an address
space because there would be fewer neighboring vm map entries that differed
only in the presence or absence of VM_PROT_EXECUTE.  (See vm/vm_mmap.c
revision 1.56.)

Today, I don't see any real applications that benefit from
VM_PROT_READ_IS_EXEC.  In any case, vm map entries are now organized
as a self-adjusting binary search tree instead of an ordered list.  So,
the need for coalescing vm map entries is not as great as it once was.
2009-04-04 23:12:14 +00:00
..
amd64 Reduce code duplcations from r190620. While I am here, tweak a comment. 2009-04-02 01:46:57 +00:00
arm Retire VM_PROT_READ_IS_EXEC. It was intended to be a micro-optimization, 2009-04-04 23:12:14 +00:00
boot Probe size of installed memory modules from loader and display it 2009-03-31 21:02:55 +00:00
bsm Merge OpenBSM 1.1 beta 1 from OpenBSM vendor branch to head, both 2009-03-02 13:29:18 +00:00
cam Add interleaving root hold tokens from the CAM probe to disk_create and geom 2009-04-03 19:49:33 +00:00
cddl Add a how argument to root_mount_hold() so it can be passed NOWAIT and be called 2009-04-03 19:46:12 +00:00
compat Regen 2009-04-01 13:12:40 +00:00
conf Modularize the Macintosh built-in ATA along the lines of the rest of the 2009-04-04 17:05:17 +00:00
contrib Add uath(4) wireless USB driver for Atheros AR5005UG and AR5005UX 2009-04-04 11:23:00 +00:00
crypto identify routine takes driver_t *, not device_t *. 2009-02-05 19:30:28 +00:00
ddb Prefer prototypes to k&r definitions. 2009-03-09 13:32:19 +00:00
dev - Add the support for the Asus A3F and A3E device 2009-04-04 17:01:32 +00:00
fs Do not use null_bypass for VOP_ISLOCKED, directly call default 2009-03-18 13:54:35 +00:00
gdb
geom Add interleaving root hold tokens from the CAM probe to disk_create and geom 2009-04-03 19:49:33 +00:00
gnu Fix two issues with bufdaemon, often causing the processes to hang in 2009-03-16 15:39:46 +00:00
i386 Retire VM_PROT_READ_IS_EXEC. It was intended to be a micro-optimization, 2009-04-04 23:12:14 +00:00
ia64 Add trivial implementation for the freebsd32_sysarch on ia64. 2009-04-01 19:23:07 +00:00
isa Allow syscons to work on amd64 and i386 without any hints: 2009-03-05 19:10:17 +00:00
kern Revert change 190655 temporarily. It breaks many setups where nullfs is 2009-04-04 17:48:38 +00:00
kgssapi Call svc_freereq() before returning from the service proc. 2008-11-12 15:31:05 +00:00
legacy/dev remove now-redunant cardbus attachment lines. 2009-03-09 13:25:34 +00:00
libkern Add memmove() to the kernel, making the kernel compile with Clang. 2009-02-28 16:21:25 +00:00
mips Mark the declaration of bus_space_map 'static' as the implementation is. 2009-03-28 23:24:34 +00:00
modules Add uath(4) wireless USB driver for Atheros AR5005UG and AR5005UX 2009-04-04 11:23:00 +00:00
net Sync DLTs with latest libpcap version. 2009-04-02 13:02:12 +00:00
net80211 fix whitespace 2009-04-03 20:46:32 +00:00
netatalk Remove local variable 'ddp' from DDP's attach and detach routines; they 2009-02-04 20:04:32 +00:00
netgraph Make Netgraph compile with Clang. 2009-03-03 18:47:33 +00:00
netinet Fix mbuf chain layout pessimization: 2009-04-04 15:32:23 +00:00
netinet6 Introduce a number of changes to the MROUTING code. 2009-03-19 01:43:03 +00:00
netipsec Fixed comments so it stays in 80 chars by line 2009-03-23 16:20:39 +00:00
netipx Add missing "goto set_head" for SO_IPX_CHECKSUM; otherwise we fall through 2008-12-11 10:29:35 +00:00
netnatm Remove IFF_NEEDSGIANT, a compatibility infrastructure introduced 2009-03-15 14:21:05 +00:00
netncp
netsmb Implement device cloning for /dev/nsmb, the netsmb control pseudo-device. 2008-11-03 14:23:15 +00:00
nfs
nfs4client Expand the per-node access cache to cache permissions for multiple users. 2009-03-20 21:12:38 +00:00
nfsclient Move dtnfsclient.c in the cddl tree to nfs_kdtrace.c in the nfsclient 2009-03-25 17:47:22 +00:00
nfsserver Fix an mbuf leak in the error path. 2009-03-19 14:13:18 +00:00
nlm Don't call svc_freereq() before svc_freeargs(). 2008-11-12 15:30:30 +00:00
opencrypto Fix return type for detach routine (should be int) 2009-02-05 17:43:12 +00:00
pc98 MFi386: r190447 2009-03-27 03:45:42 +00:00
pci intpm: minor enhancements 2009-03-16 16:15:14 +00:00
powerpc Perform a dummy stwcx. when we switch contexts. The context 2009-04-04 22:23:03 +00:00
rpc Use the correct creds when reconnecting so that we have enough privilege to 2009-02-05 11:48:10 +00:00
security Get rid of VSTAT and replace it with VSTAT_PERMS, which is somewhat 2009-03-29 17:45:48 +00:00
sparc64 Revert r190105 so that removing options KDB but DDB or GDB being 2009-03-20 17:10:50 +00:00
sun4v - There's no need to wrap kdb_active and kdb_trap() in #ifdef KDB as 2009-03-19 20:46:51 +00:00
sys PowerPC, meet kernel core dumps. The support is based 2009-04-04 02:12:37 +00:00
tools Add SDT DTrace probes for VFS vnode operations in the vfs:vop 2009-03-29 03:30:15 +00:00
ufs When removing or renaming snaphost, do not delve into request_cleanup(). 2009-04-04 12:19:52 +00:00
vm Retire VM_PROT_READ_IS_EXEC. It was intended to be a micro-optimization, 2009-04-04 23:12:14 +00:00
xdr Add memmove() to the kernel, making the kernel compile with Clang. 2009-02-28 16:21:25 +00:00
xen Fix the Xen build for i386 PV mode. 2009-04-01 17:06:28 +00:00
Makefile Removal pccard directory requires removing it from the list of things 2009-02-15 18:19:24 +00:00