Skip to content

R
raspberrypi-kernel

openeuler / raspberrypi-kernel

通知 13
Star 1
Fork 0
R
raspberrypi-kernel
切换分支/标签
  1. 08 7月, 2006 1 次提交
    • D
      [PATCH] Fix cpufreq vs hotplug lockdep recursion. · a496e25d
      由 Dave Jones 提交于 
      [ There's some not quite baked bits in cpufreq-git right now
  so sending this on as a patch instead ]

On Thu, 2006-07-06 at 07:58 -0700, Tom London wrote:

> After installing .2356 I get this each time I boot:
> =======================================================
> [ INFO: possible circular locking dependency detected ]
> -------------------------------------------------------
> S06cpuspeed/1620 is trying to acquire lock:
>  (dbs_mutex){--..}, at: [<c060d6bb>] mutex_lock+0x21/0x24
>
> but task is already holding lock:
>  (cpucontrol){--..}, at: [<c060d6bb>] mutex_lock+0x21/0x24
>
> which lock already depends on the new lock.
>

make sure the cpu hotplug recursive mutex (yuck) is taken early in the
cpufreq codepaths to avoid a AB-BA deadlock.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      a496e25d
  3. 01 7月, 2006 1 次提交
  5. 30 6月, 2006 3 次提交
  7. 28 6月, 2006 3 次提交
  9. 23 6月, 2006 1 次提交
    • A
      [PATCH] cpufreq build fix · 138a0128
      由 Andrew Morton 提交于 
      drivers/cpufreq/cpufreq_ondemand.c: In function 'do_dbs_timer':
drivers/cpufreq/cpufreq_ondemand.c:374: warning: implicit declaration of function 'lock_cpu_hotplug'
drivers/cpufreq/cpufreq_ondemand.c:381: warning: implicit declaration of function 'unlock_cpu_hotplug'
drivers/cpufreq/cpufreq_conservative.c: In function 'do_dbs_timer':
drivers/cpufreq/cpufreq_conservative.c:425: warning: implicit declaration of function 'lock_cpu_hotplug'
drivers/cpufreq/cpufreq_conservative.c:432: warning: implicit declaration of function 'unlock_cpu_hotplug'

Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      138a0128
  11. 22 6月, 2006 1 次提交
    • V
      [CPUFREQ] Fix ondemand vs suspend deadlock · 4ec223d0
      由 Venkatesh Pallipadi 提交于 
      Rootcaused the bug to a deadlock in cpufreq and ondemand. Due to non-existent
ordering between cpu_hotplug lock and dbs_mutex. Basically a race condition
between cpu_down() and do_dbs_timer().

cpu_down() flow:
* cpu_down() call for CPU 1
* Takes hot plug lock
* Calls pre down notifier
*     cpufreq notifier handler calls cpufreq_driver_target() which takes
      cpu_hotplug lock again. OK as cpu_hotplug lock is recursive in same
      process context
* CPU 1 goes down
* Calls post down notifier
*     cpufreq notifier handler calls ondemand event stop which takes dbs_mutex

So, cpu_hotplug lock is taken before dbs_mutex in this flow.

do_dbs_timer is triggerred by a periodic timer event.
It first takes dbs_mutex and then takes cpu_hotplug lock in
cpufreq_driver_target().
Note the reverse order here compared to above. So, if this timer event happens
at right moment during cpu_down, system will deadlok.

Attached patch fixes the issue for both ondemand and conservative.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NDave Jones <davej@redhat.com>
      4ec223d0
  13. 05 6月, 2006 1 次提交
  15. 31 5月, 2006 4 次提交
  17. 09 5月, 2006 1 次提交
  19. 26 4月, 2006 1 次提交
  21. 19 4月, 2006 2 次提交
    • A
      [CPUFREQ] drivers/cpufreq/cpufreq.c: static functions mustn't be exported · 7b14dedd
      由 Adrian Bunk 提交于 
      This patch removes the EXPORT_SYMBOL_GPL of the static function cpufreq_parse_governor().
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NDave Jones <davej@redhat.com>
      7b14dedd
    • T
      [CPUFREQ] If max_freq got reduced (e.g. by _PPC) a write to sysfs... · 7970e08b
      由 Thomas Renninger 提交于 
      [CPUFREQ] If max_freq got reduced (e.g. by _PPC) a write to sysfs scaling_governor let cpufreq core stuck at low max_freq for ever

The previous patch had bugs (locking and refcount).

This one could also be related to the latest DELL reports.
But they only slip into this if a user prog (e.g. powersave daemon does when
AC got (un) plugged due to a scheme change) echos something to
/sys/../cpufreq/scaling_governor
while the frequencies got limited by BIOS.

This one works:

Subject: Max freq stucks at low freq if reduced by _PPC and sysfs gov access

The problem is reproducable by(if machine is limiting freqs via BIOS):
 - Unplugging AC -> max freq gets limited
 - echo ${governor} >/sys/.../cpufreq/scaling_governor (policy->user_data.max
   gets overridden with policy->max and will never come up again.)

This patch exchanged the cpufreq_set_policy call to __cpufreq_set_policy and
duplicated it's functionality but did not override user_data.max.
The same happens with overridding min/max values. If freqs are limited and
you override the min freq value, the max freq global value will also get
stuck to the limited freq, even if BIOS allows all freqs again.
Last scenario does only happen if BIOS does not reduce the frequency
to the lowest value (should never happen, just for correctness...)

 drivers/cpufreq/cpufreq.c |   17 +++++++++++++++--
 1 files changed, 15 insertions(+), 2 deletions(-)
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: N"Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
Signed-off-by: NDave Jones <davej@redhat.com>
      7970e08b
  23. 03 4月, 2006 1 次提交
  25. 02 4月, 2006 1 次提交
  27. 29 3月, 2006 3 次提交
  29. 28 3月, 2006 1 次提交
    • A
      [PATCH] Notifier chain update: API changes · e041c683
      由 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
  31. 26 3月, 2006 7 次提交
  33. 12 3月, 2006 1 次提交
    • S
      [PATCH] cpufreq: fix section mismatch warnings · bb1a813d
      由 Sam Ravnborg 提交于 
      cpufreq are the only remaining bit to be solved for me to have a modpost
clean build for sparc64 - so I took one more look at it.
changelog entry:

Fix section mismatch warnings in cpufreq:
WARNING: drivers/cpufreq/cpufreq_stats.o - Section mismatch: reference to .init.text: from .data between 'cpufreq_stat_cpu_notifier' (at offset 0xa8) and 'notifier_policy_block'
WARNING: drivers/cpufreq/cpufreq_stats.o - Section mismatch: reference to .init.text: from .exit.text after 'cleanup_module' (at offset 0x30)

The culprint is the function: cpufreq_stat_cpu_callback
It is marked __cpuinit which get's redefined to __init in case
HOTPLUG_CPU is not enabled as per. init.h:

#ifdef CONFIG_HOTPLUG_CPU
#define __cpuinit
#else
#define __cpuinit       __init
#endif

$> grep HOTPLUG .config
CONFIG_HOTPLUG=y

But cpufreq_stat_cpu_callback() is used in:
__exit cpufreq_stats_exit()
static struct notifier_block cpufreq_stat_cpu_notifier

cpufreq_stat_cpu_notifier is again used in:
__init cpufreq_stats_init()
__exit cpufreq_stats_exit()

So in both cases used from both __init and __exit context.
Only solution seems to drop __cpuinit tag.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDave Jones <davej@redhat.com>
      bb1a813d
  35. 05 3月, 2006 1 次提交
  37. 28 2月, 2006 1 次提交
  39. 03 2月, 2006 2 次提交
  41. 01 2月, 2006 1 次提交
  43. 28 1月, 2006 1 次提交
  45. 27 1月, 2006 1 次提交