1. 26 7月, 2008 2 次提交
  2. 19 7月, 2008 1 次提交
    • M
      cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr · 65c01184
      Mike Travis 提交于
        * This patch replaces the dangerous lvalue version of cpumask_of_cpu
          with new cpumask_of_cpu_ptr macros.  These are patterned after the
          node_to_cpumask_ptr macros.
      
          In general terms, if there is a cpumask_of_cpu_map[] then a pointer to
          the cpumask_of_cpu_map[cpu] entry is used.  The cpumask_of_cpu_map
          is provided when there is a large NR_CPUS count, reducing
          greatly the amount of code generated and stack space used for
          cpumask_of_cpu().  The pointer to the cpumask_t value is needed for
          calling set_cpus_allowed_ptr() to reduce the amount of stack space
          needed to pass the cpumask_t value.
      
          If there isn't a cpumask_of_cpu_map[], then a temporary variable is
          declared and filled in with value from cpumask_of_cpu(cpu) as well as
          a pointer variable pointing to this temporary variable.  Afterwards,
          the pointer is used to reference the cpumask value.  The compiler
          will optimize out the extra dereference through the pointer as well
          as the stack space used for the pointer, resulting in identical code.
      
          A good example of the orthogonal usages is in net/sunrpc/svc.c:
      
      	case SVC_POOL_PERCPU:
      	{
      		unsigned int cpu = m->pool_to[pidx];
      		cpumask_of_cpu_ptr(cpumask, cpu);
      
      		*oldmask = current->cpus_allowed;
      		set_cpus_allowed_ptr(current, cpumask);
      		return 1;
      	}
      	case SVC_POOL_PERNODE:
      	{
      		unsigned int node = m->pool_to[pidx];
      		node_to_cpumask_ptr(nodecpumask, node);
      
      		*oldmask = current->cpus_allowed;
      		set_cpus_allowed_ptr(current, nodecpumask);
      		return 1;
      	}
      Signed-off-by: NMike Travis <travis@sgi.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      65c01184
  3. 29 4月, 2008 1 次提交
  4. 20 4月, 2008 1 次提交
    • M
      generic: use new set_cpus_allowed_ptr function · f70316da
      Mike Travis 提交于
        * Use new set_cpus_allowed_ptr() function added by previous patch,
          which instead of passing the "newly allowed cpus" cpumask_t arg
          by value,  pass it by pointer:
      
          -int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
          +int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)
      
        * Modify CPU_MASK_ALL
      
      Depends on:
      	[sched-devel]: sched: add new set_cpus_allowed_ptr function
      Signed-off-by: NMike Travis <travis@sgi.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      f70316da
  5. 19 4月, 2008 1 次提交
  6. 07 2月, 2008 1 次提交
  7. 12 7月, 2007 1 次提交
    • Z
      sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sysfs binary attributes · 91a69029
      Zhang Rui 提交于
      Well, first of all, I don't want to change so many files either.
      
      What I do:
      Adding a new parameter "struct bin_attribute *" in the
      .read/.write methods for the sysfs binary attributes.
      
      In fact, only the four lines change in fs/sysfs/bin.c and
      include/linux/sysfs.h do the real work.
      But I have to update all the files that use binary attributes
      to make them compatible with the new .read and .write methods.
      I'm not sure if I missed any. :(
      
      Why I do this:
      For a sysfs attribute, we can get a pointer pointing to the
      struct attribute in the .show/.store method,
      while we can't do this for the binary attributes.
      I don't know why this is different, but this does make it not
      so handy to use the binary attributes as the regular ones.
      So I think this patch is reasonable. :)
      
      Who benefits from it:
      The patch that exposes ACPI tables in sysfs
      requires such an improvement.
      All the table binary attributes share the same .read method.
      Parameter "struct bin_attribute *" is used to get
      the table signature and instance number which are used to
      distinguish different ACPI table binary attributes.
      
      Without this parameter, we need to offer different .read methods
      for different ACPI table binary attributes.
      This is impossible as there are various ACPI tables on different
      platforms, and we don't know what they are until they are loaded.
      Signed-off-by: NZhang Rui <rui.zhang@intel.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      91a69029
  8. 21 10月, 2006 1 次提交
  9. 11 10月, 2006 1 次提交
  10. 28 3月, 2006 1 次提交
    • A
      [PATCH] Notifier chain update: API changes · e041c683
      Alan Stern 提交于
      The kernel's implementation of notifier chains is unsafe.  There is no
      protection against entries being added to or removed from a chain while the
      chain is in use.  The issues were discussed in this thread:
      
          http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2
      
      We noticed that notifier chains in the kernel fall into two basic usage
      classes:
      
      	"Blocking" chains are always called from a process context
      	and the callout routines are allowed to sleep;
      
      	"Atomic" chains can be called from an atomic context and
      	the callout routines are not allowed to sleep.
      
      We decided to codify this distinction and make it part of the API.  Therefore
      this set of patches introduces three new, parallel APIs: one for blocking
      notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
      really just the old API under a new name).  New kinds of data structures are
      used for the heads of the chains, and new routines are defined for
      registration, unregistration, and calling a chain.  The three APIs are
      explained in include/linux/notifier.h and their implementation is in
      kernel/sys.c.
      
      With atomic and blocking chains, the implementation guarantees that the chain
      links will not be corrupted and that chain callers will not get messed up by
      entries being added or removed.  For raw chains the implementation provides no
      guarantees at all; users of this API must provide their own protections.  (The
      idea was that situations may come up where the assumptions of the atomic and
      blocking APIs are not appropriate, so it should be possible for users to
      handle these things in their own way.)
      
      There are some limitations, which should not be too hard to live with.  For
      atomic/blocking chains, registration and unregistration must always be done in
      a process context since the chain is protected by a mutex/rwsem.  Also, a
      callout routine for a non-raw chain must not try to register or unregister
      entries on its own chain.  (This did happen in a couple of places and the code
      had to be changed to avoid it.)
      
      Since atomic chains may be called from within an NMI handler, they cannot use
      spinlocks for synchronization.  Instead we use RCU.  The overhead falls almost
      entirely in the unregister routine, which is okay since unregistration is much
      less frequent that calling a chain.
      
      Here is the list of chains that we adjusted and their classifications.  None
      of them use the raw API, so for the moment it is only a placeholder.
      
        ATOMIC CHAINS
        -------------
      arch/i386/kernel/traps.c:		i386die_chain
      arch/ia64/kernel/traps.c:		ia64die_chain
      arch/powerpc/kernel/traps.c:		powerpc_die_chain
      arch/sparc64/kernel/traps.c:		sparc64die_chain
      arch/x86_64/kernel/traps.c:		die_chain
      drivers/char/ipmi/ipmi_si_intf.c:	xaction_notifier_list
      kernel/panic.c:				panic_notifier_list
      kernel/profile.c:			task_free_notifier
      net/bluetooth/hci_core.c:		hci_notifier
      net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_chain
      net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_expect_chain
      net/ipv6/addrconf.c:			inet6addr_chain
      net/netfilter/nf_conntrack_core.c:	nf_conntrack_chain
      net/netfilter/nf_conntrack_core.c:	nf_conntrack_expect_chain
      net/netlink/af_netlink.c:		netlink_chain
      
        BLOCKING CHAINS
        ---------------
      arch/powerpc/platforms/pseries/reconfig.c:	pSeries_reconfig_chain
      arch/s390/kernel/process.c:		idle_chain
      arch/x86_64/kernel/process.c		idle_notifier
      drivers/base/memory.c:			memory_chain
      drivers/cpufreq/cpufreq.c		cpufreq_policy_notifier_list
      drivers/cpufreq/cpufreq.c		cpufreq_transition_notifier_list
      drivers/macintosh/adb.c:		adb_client_list
      drivers/macintosh/via-pmu.c		sleep_notifier_list
      drivers/macintosh/via-pmu68k.c		sleep_notifier_list
      drivers/macintosh/windfarm_core.c	wf_client_list
      drivers/usb/core/notify.c		usb_notifier_list
      drivers/video/fbmem.c			fb_notifier_list
      kernel/cpu.c				cpu_chain
      kernel/module.c				module_notify_list
      kernel/profile.c			munmap_notifier
      kernel/profile.c			task_exit_notifier
      kernel/sys.c				reboot_notifier_list
      net/core/dev.c				netdev_chain
      net/decnet/dn_dev.c:			dnaddr_chain
      net/ipv4/devinet.c:			inetaddr_chain
      
      It's possible that some of these classifications are wrong.  If they are,
      please let us know or submit a patch to fix them.  Note that any chain that
      gets called very frequently should be atomic, because the rwsem read-locking
      used for blocking chains is very likely to incur cache misses on SMP systems.
      (However, if the chain's callout routines may sleep then the chain cannot be
      atomic.)
      
      The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
      material written by Keith Owens and suggestions from Paul McKenney and Andrew
      Morton.
      
      [jes@sgi.com: restructure the notifier chain initialization macros]
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
      Signed-off-by: NJes Sorensen <jes@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      e041c683
  11. 23 3月, 2006 1 次提交
  12. 22 3月, 2006 1 次提交
  13. 10 3月, 2006 1 次提交
  14. 30 10月, 2005 1 次提交
  15. 08 9月, 2005 1 次提交