svn commit: r310805 - in head/sys: kern sys vm

[Mateusz Guzik]

Author: mjg
Date: Fri Dec 30 06:26:17 2016
New Revision: 310805
URL: https://svnweb.freebsd.org/changeset/base/310805

Log:
  Remove cpu_spinwait after seq_consistent.
  
  It does not add any benefit as the read routine will do it as necessary.

Modified:
  head/sys/kern/kern_descrip.c
  head/sys/sys/seq.h
  head/sys/vm/vm_domain.c

Modified: head/sys/kern/kern_descrip.c
==============================================================================
--- head/sys/kern/kern_descrip.c        Fri Dec 30 03:08:46 2016        
(r310804)
+++ head/sys/kern/kern_descrip.c        Fri Dec 30 06:26:17 2016        
(r310805)
@@ -2556,10 +2556,8 @@ fget_unlocked(struct filedesc *fdp, int 
                fde = &fdt->fdt_ofiles[fd];
                haverights = *cap_rights_fde(fde);
                fp = fde->fde_file;
-               if (!seq_consistent(fd_seq(fdt, fd), seq)) {
-                       cpu_spinwait();
+               if (!seq_consistent(fd_seq(fdt, fd), seq))
                        continue;
-               }
 #else
                fp = fdt->fdt_ofiles[fd].fde_file;
 #endif

Modified: head/sys/sys/seq.h
==============================================================================
--- head/sys/sys/seq.h  Fri Dec 30 03:08:46 2016        (r310804)
+++ head/sys/sys/seq.h  Fri Dec 30 06:26:17 2016        (r310805)
@@ -59,7 +59,6 @@ typedef uint32_t seq_t;
  *             lobj = gobj;
  *             if (seq_consistent(&gobj->seq, seq))
  *                     break;
- *             cpu_spinwait();
  *     }
  *     foo(lobj);
  */            

Modified: head/sys/vm/vm_domain.c
==============================================================================
--- head/sys/vm/vm_domain.c     Fri Dec 30 03:08:46 2016        (r310804)
+++ head/sys/vm/vm_domain.c     Fri Dec 30 06:26:17 2016        (r310805)
@@ -140,7 +140,6 @@ vm_domain_policy_localcopy(struct vm_dom
                *dst = *src;
                if (seq_consistent(&src->seq, seq))
                        return;
-               cpu_spinwait();
        }
 }
 
@@ -168,7 +167,6 @@ vm_domain_policy_copy(struct vm_domain_p
                        seq_write_end(&dst->seq);
                        return;
                }
-               cpu_spinwait();
        }
 }
 
@@ -330,7 +328,6 @@ vm_domain_iterator_set_policy(struct vm_
                        _vm_domain_iterator_set_policy(vi, &vt_lcl);
                        return;
                }
-               cpu_spinwait();
        }
 }
 
_______________________________________________
svn-src-all@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"