[hurd,commited] hurd: Remove optimizing anonymous maps as __vm_allocate.

Message ID 20190829234255.22457-1-samuel.thibault@ens-lyon.org
State Committed, archived
Headers

Commit Message

Samuel Thibault Aug. 29, 2019, 11:42 p.m. UTC
  Optimizing anonymous maps brings bugs, and does not optimize much anyway.

	[BZ #19903]
	* sysdeps/mach/hurd/mmap.c (__mmap): Remove optimizing anonymous maps
	as __vm_allocate.
---
 ChangeLog                |  4 ++++
 sysdeps/mach/hurd/mmap.c | 23 -----------------------
 2 files changed, 4 insertions(+), 23 deletions(-)
  

Patch

diff --git a/ChangeLog b/ChangeLog
index afd99a634e..98a86369d5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -20,6 +20,10 @@ 
 	EBADF case, or else POLLERR.
 	- On error, make select simulated readiness.
 
+	[BZ #19903]
+	* sysdeps/mach/hurd/mmap.c (__mmap): Remove optimizing anonymous maps
+	as __vm_allocate.
+
 2019-08-30  Richard Braun  <rbraun@sceen.net>
 
 	* hurd/hurdselect.c (_hurd_select): Always call __io_select with no
diff --git a/sysdeps/mach/hurd/mmap.c b/sysdeps/mach/hurd/mmap.c
index 8eb741f7e1..e3ff77d6c9 100644
--- a/sysdeps/mach/hurd/mmap.c
+++ b/sysdeps/mach/hurd/mmap.c
@@ -44,29 +44,6 @@  __mmap (void *addr, size_t len, int prot, int flags, int fd, off_t offset)
   if ((mapaddr & (__vm_page_size - 1)) || (offset & (__vm_page_size - 1)))
     return (void *) (long int) __hurd_fail (EINVAL);
 
-  if ((flags & (MAP_TYPE|MAP_INHERIT)) == MAP_ANON
-      && prot == (PROT_READ|PROT_WRITE)) /* cf VM_PROT_DEFAULT */
-    {
-      /* vm_allocate has (a little) less overhead in the kernel too.  */
-      err = __vm_allocate (__mach_task_self (), &mapaddr, len, mapaddr == 0);
-
-      if (err == KERN_NO_SPACE)
-	{
-	  if (flags & MAP_FIXED)
-	    {
-	      /* XXX this is not atomic as it is in unix! */
-	      /* The region is already allocated; deallocate it first.  */
-	      err = __vm_deallocate (__mach_task_self (), mapaddr, len);
-	      if (!err)
-		err = __vm_allocate (__mach_task_self (), &mapaddr, len, 0);
-	    }
-	  else if (mapaddr != 0)
-	    err = __vm_allocate (__mach_task_self (), &mapaddr, len, 1);
-	}
-
-      return err ? (void *) (long int) __hurd_fail (err) : (void *) mapaddr;
-    }
-
   vmprot = VM_PROT_NONE;
   if (prot & PROT_READ)
     vmprot |= VM_PROT_READ;