1. 25 10月, 2007 2 次提交
    • I
      sched: fix fastcall mismatch in completion APIs · b15136e9
      Ingo Molnar 提交于
      Jeff Dike noticed that wait_for_completion_interruptible()'s prototype
      had a mismatched fastcall.
      
      Fix this by removing the fastcall attributes from all the completion APIs.
      Found-by: NJeff Dike <jdike@linux.intel.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      b15136e9
    • M
      sched: fix sched_domain sysctl registration again · 7378547f
      Milton Miller 提交于
      commit  029190c5 (cpuset
      sched_load_balance flag) was not tested SCHED_DEBUG enabled as
      committed as it dereferences NULL when used and it reordered
      the sysctl registration to cause it to never show any domains
      or their tunables.
      
      Fixes:
      
      1) restore arch_init_sched_domains ordering
      	we can't walk the domains before we build them
      
      	presently we register cpus with empty directories (no domain
      	directories or files).
      
      2) make unregister_sched_domain_sysctl do nothing when already unregistered
      	detach_destroy_domains is now called one set of cpus at a time
      	unregister_syctl dereferences NULL if called with a null.
      
      	While the the function would always dereference null if called
      	twice, in the previous code it was always called once and then
      	was followed a register.  So only the hidden bug of the
      	sysctl_root_table not being allocated followed by an attempt to
      	free it would have shown the error.
      
      3) always call unregister and register in partition_sched_domains
      	The code is "smart" about unregistering only needed domains.
      	Since we aren't guaranteed any calls to unregister, always 
      	unregister.   Without calling register on the way out we
      	will not have a table or any sysctl tree.
      
      4) warn if register is called without unregistering
      	The previous table memory is lost, leaving pointers to the
      	later freed memory in sysctl and leaking the memory of the
      	tables.
      
      Before this patch on a 2-core 4-thread box compiled for SMT and NUMA,
      the domains appear empty (there are actually 3 levels per cpu).  And as
      soon as two domains a null pointer is dereferenced (unreliable in this
      case is stack garbage):
      
      bu19a:~# ls -R /proc/sys/kernel/sched_domain/
      /proc/sys/kernel/sched_domain/:
      cpu0  cpu1  cpu2  cpu3
      
      /proc/sys/kernel/sched_domain/cpu0:
      
      /proc/sys/kernel/sched_domain/cpu1:
      
      /proc/sys/kernel/sched_domain/cpu2:
      
      /proc/sys/kernel/sched_domain/cpu3:
      
      bu19a:~# mkdir /dev/cpuset
      bu19a:~# mount -tcpuset cpuset /dev/cpuset/
      bu19a:~# cd /dev/cpuset/
      bu19a:/dev/cpuset# echo 0 > sched_load_balance 
      bu19a:/dev/cpuset# mkdir one
      bu19a:/dev/cpuset# echo 1 > one/cpus               
      bu19a:/dev/cpuset# echo 0 > one/sched_load_balance 
      Unable to handle kernel paging request for data at address 0x00000018
      Faulting instruction address: 0xc00000000006b608
      NIP: c00000000006b608 LR: c00000000006b604 CTR: 0000000000000000
      REGS: c000000018d973f0 TRAP: 0300   Not tainted  (2.6.23-bml)
      MSR: 9000000000009032 <EE,ME,IR,DR>  CR: 28242442  XER: 00000000
      DAR: 0000000000000018, DSISR: 0000000040000000
      TASK = c00000001912e340[1987] 'bash' THREAD: c000000018d94000 CPU: 2
      ..
      NIP [c00000000006b608] .unregister_sysctl_table+0x38/0x110
      LR [c00000000006b604] .unregister_sysctl_table+0x34/0x110
      Call Trace:
      [c000000018d97670] [c000000007017270] 0xc000000007017270 (unreliable)
      [c000000018d97720] [c000000000058710] .detach_destroy_domains+0x30/0xb0
      [c000000018d977b0] [c00000000005cf1c] .partition_sched_domains+0x1bc/0x230
      [c000000018d97870] [c00000000009fdc4] .rebuild_sched_domains+0xb4/0x4c0
      [c000000018d97970] [c0000000000a02e8] .update_flag+0x118/0x170
      [c000000018d97a80] [c0000000000a1768] .cpuset_common_file_write+0x568/0x820
      [c000000018d97c00] [c00000000009d95c] .cgroup_file_write+0x7c/0x180
      [c000000018d97cf0] [c0000000000e76b8] .vfs_write+0xe8/0x1b0
      [c000000018d97d90] [c0000000000e810c] .sys_write+0x4c/0x90
      [c000000018d97e30] [c00000000000852c] syscall_exit+0x0/0x40
      Signed-off-by: NMilton Miller <miltonm@bga.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      7378547f
  2. 24 10月, 2007 38 次提交