Joonyoung Shim [Mon, 16 Mar 2009 12:23:35 +0000 (21:23 +0900)]
ASoC: twl4030 - Fix build error
CC sound/soc/codecs/twl4030.o
sound/soc/codecs/twl4030.c:1400: warning: braces around scalar initializer
sound/soc/codecs/twl4030.c:1400: warning: (near initialization for 'twl4030_dai.ops')
sound/soc/codecs/twl4030.c:1401: error: field name not in record or union initializer
sound/soc/codecs/twl4030.c:1401: error: (near initialization for 'twl4030_dai.ops')
sound/soc/codecs/twl4030.c:1401: warning: initialization from incompatible pointer type
sound/soc/codecs/twl4030.c:1402: error: field name not in record or union initializer
sound/soc/codecs/twl4030.c:1402: error: (near initialization for 'twl4030_dai.ops')
sound/soc/codecs/twl4030.c:1402: warning: excess elements in scalar initializer
sound/soc/codecs/twl4030.c:1402: warning: (near initialization for 'twl4030_dai.ops')
sound/soc/codecs/twl4030.c:1403: error: field name not in record or union initializer
sound/soc/codecs/twl4030.c:1403: error: (near initialization for 'twl4030_dai.ops')
sound/soc/codecs/twl4030.c:1403: warning: excess elements in scalar initializer
sound/soc/codecs/twl4030.c:1403: warning: (near initialization for 'twl4030_dai.ops')
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Eric Leblond [Mon, 16 Mar 2009 13:55:27 +0000 (14:55 +0100)]
netfilter: print the list of register loggers
This patch modifies the proc output to add display of registered
loggers. The content of /proc/net/netfilter/nf_log is modified. Instead
of displaying a protocol per line with format:
proto:logger
it now displays:
proto:logger (comma_separated_list_of_loggers)
NONE is used as keyword if no logger is used.
Signed-off-by: Eric Leblond <eric@inl.fr> Signed-off-by: Patrick McHardy <kaber@trash.net>
Eric Leblond [Mon, 16 Mar 2009 13:54:21 +0000 (14:54 +0100)]
netfilter: use a linked list of loggers
This patch modifies nf_log to use a linked list of loggers for each
protocol. This list of loggers is read and write protected with a
mutex.
This patch separates registration and binding. To be used as
logging module, a module has to register calling nf_log_register()
and to bind to a protocol it has to call nf_log_bind_pf().
This patch also converts the logging modules to the new API. For nfnetlink_log,
it simply switchs call to register functions to call to bind function and
adds a call to nf_log_register() during init. For other modules, it just
remove a const flag from the logger structure and replace it with a
__read_mostly.
Signed-off-by: Eric Leblond <eric@inl.fr> Signed-off-by: Patrick McHardy <kaber@trash.net>
sh: Move IRQ multi definition of DMAC to defconfig
When SuperH CPU has IRQ multi of DMAC, SH_DMA_IRQ_MULTI becomes enable.
The following CPU's are Multi IRQ of DMAC now.
- SH775X and SH7091
- SH776X
- SH7780
- SH7785
If SH_DMA_IRQ_MULTI becomes enable, dma-sh api driver is optimized
for Multi IRQ.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch fixes a possible problem in the resume from
hibenration. It temporaneally saves the clk->rate on the
stack to avoid any possible change during the clk->set_parent(..)
call.
Signed-off-by: Francesco Virlinzi <francesco.virlinzi@st.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Magnus Damm [Fri, 13 Mar 2009 15:36:55 +0000 (15:36 +0000)]
video: sh_mobile_lcdcfb suspend/resume support
This patch adds suspend/resume support to the LCDC
driver for SuperH Mobile - sh_mobile_lcdcfb.
We simply stop hardware on suspend and start it again
on resume. For RGB panels this is trivial, but for SYS
panels in deferred io mode this becomes a bit more
difficult - we need to wait for a frame end interrupt
to make sure the clocks are balanced before stopping
the actual hardware.
Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Magnus Damm [Fri, 13 Mar 2009 15:23:04 +0000 (15:23 +0000)]
sh: SuperH Mobile suspend support
This patch contains CONFIG_SUSPEND support to the SuperH
architecture. If enabled, SuperH Mobile processors will
register their suspend callbacks during boot.
To suspend, use "echo mem > /sys/power/state". To allow
wakeup, make sure "/sys/device/platform/../power/wakeup"
contains "enabled". Additional per-device driver patches
are most likely needed.
Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Artem Bityutskiy [Mon, 16 Mar 2009 07:56:57 +0000 (09:56 +0200)]
UBIFS: introduce a helpful variable
This patch introduces a helpful @c->idx_leb_size variable.
The patch also fixes some spelling issues and makes comments
use "LEB" instead of "eraseblock", which is more correct.
Hidetoshi Seto [Mon, 16 Mar 2009 08:07:33 +0000 (17:07 +0900)]
x86, mce: remove incorrect __cpuinit for intel_init_cmci()
Impact: Bug fix on UP
Referring commit cc3ca22063784076bd240fda87217387a8f2ae92,
Peter removed __cpuinit annotations for mce_cpu_features()
and its successor functions, which caused troubles on UP
configurations.
However the intel_init_cmci() was introduced after that and
it also has __cpuinit annotation even though it is called from
mce_cpu_features(). Remove the annotation from that function
too.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
While ring-buffer allocation, the cpumasks are allocated too,
including the tracing cpumask and the per-cpu file mask handler.
But these cpumasks are freed accidentally just after.
Fix it.
The arch code builds a table to find the syscall metadata by syscall
number. It needs the syscalls names resolution from the symbol table
to know which name found on the syscalls metadatas match a function
pointer from the arch sys_call_table.
The syscall tracer uses a refcounter to enable several users
simultaneously.
But the refcounter did not behave correctly and always restored
its value to 0 after calling start_syscall_tracing(). Therefore,
stop_syscall_tracing() couldn't release correctly the tasks from
tracing.
Also the tracer forgot to reset the buffer when it is released.
Drop the pointless refcount decrement on start_syscall_tracing()
and reset the buffer when we release the tracer.
This fixes two reported issue:
- when we switch from syscall tracer to another tracer, syscall
tracing continued.
Greg Ungerer [Mon, 16 Mar 2009 08:00:25 +0000 (18:00 +1000)]
m68k: merge the non-MMU and MMU versions of sigcontext.h
It is trivial to merge the non-MMU and MMU versions of sigcontext.h.
Without a single file "make headers_install" is broken for m68k
(since each of the sub-varients of sigconext.h are not installed).
Greg Ungerer [Mon, 16 Mar 2009 07:54:49 +0000 (17:54 +1000)]
m68k: merge the non-MMU and MMU versions of swab.h
It is trivial to merge the non-MMU and MMU versions of swab.h.
Without a single file "make headers_install" is broken for m68k
(since each of the sub-varients of swab.h are not installed).
Greg Ungerer [Mon, 16 Mar 2009 07:52:16 +0000 (17:52 +1000)]
m68k: merge the non-MMU and MMU versions of param.h
It is trivial to merge the non-MMU and MMU versions of param.h.
Without a single file "make headers_install" is broken for m68k
(since each of the sub-varients of param.h are not installed).
Giuliano Pochini [Sun, 15 Mar 2009 20:33:55 +0000 (21:33 +0100)]
ALSA: echoaudio: remove line-out volume from vmixer cards
With this patch the drivers do not set the vmixer volume anymore at startup
because it is actually the output volume of the voices and ALSA mandates
that the volume must be 0 by default.
Giuliano Pochini [Sun, 15 Mar 2009 20:33:34 +0000 (21:33 +0100)]
ALSA: echoaudio: remove line-out volume from vmixer cards
There is a long standing bug in the drivers for cards with a vmixer because
I overlooked a detail in the c++ generic driver by echoaudio. Those cards
do not have a line-out volume control. It is a virtual control provided by
the generic driver. The bug is harmless because the DSP just ignores the
command to change the volume.
*NB:* It breaks alsa-tools/echomixer. A patch for it will follow.
This patch removes the line-out volume control from vmixer-equipped cards.
Most callers of xlog_bread need to call xlog_align to get the actual offset.
Consolidate that call into the main xlog_bread and provide a _xlog_bread
for those few that don't want the actual offset.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <david@fromorbit.com>
Change the big if-elsif-else block handling the different item types
into a more natural switch, remove assignments in conditionals and
remove an out of place comment from centuries ago on IRIX.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <david@fromorbit.com>
xfs: remove another leftover of the old inode log item format
There's another little snipplet of code left from the handling of the old
inode log item format in xlog_recover_do_inode_trans. Kill it as it
can't be reached anymore.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <david@fromorbit.com>
Kill the current xfs_log_unmount wrapper and opencode the two function
calls in the only caller. Rename the current xfs_log_unmount_dealloc to
xfs_log_unmount as it undoes xfs_log_mount and the new name makes that
more clear.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <david@fromorbit.com>
Roel Kluin [Wed, 4 Mar 2009 19:55:30 +0000 (11:55 -0800)]
acpi-wmi: unsigned cannot be less than 0
include/linux/pci-acpi.h:74:
typedef u32 acpi_status;
result is unsigned, so an error returned by acpi_bus_register_driver()
will not be noticed.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
thinkpad-acpi: fix module autoloading for older models
Looking at the source, there seems to be a missing * to match my DMI
string. I mean for newer IBM and Lenovo's laptops you match either one
of the following:
MODULE_ALIAS("dmi:bvnIBM:*:svnIBM:*:pvrThinkPad*:rvnIBM:*");
MODULE_ALIAS("dmi:bvnLENOVO:*:svnLENOVO:*:pvrThinkPad*:rvnLENOVO:*");
While for older Thinkpads, you do this (for instance):
IBM_BIOS_MODULE_ALIAS("1[0,3,6,8,A-G,I,K,M-P,S,T]");
with IBM_BIOS_MODULE_ALIAS being MODULE_ALIAS("dmi:bvnIBM:bvr" __type "ET??WW")
Note there's no * terminating the string. As result, udev doesn't load
anything because modprobe cannot find anything matching this (my
machine actually):
Signed-off-by: Mathieu Chouquet-Stringer <mchouque@free.fr> Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Signed-off-by: Len Brown <len.brown@intel.com>
Dan Carpenter [Sat, 14 Feb 2009 09:53:48 +0000 (09:53 +0000)]
acer-wmi: double free in acer_rfkill_exit()
This is acer_rfkill_exit() from drivers/platform/x86/acer-wmi.c.
The code frees wireless_rfkill->data again instead of
bluetooth_rfkill->data.
This was found using a code checker (http://repo.or.cz/w/smatch.git/).
Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk> Signed-off-by: Len Brown <len.brown@intel.com>
Cyrill Gorcunov [Wed, 4 Mar 2009 19:55:29 +0000 (11:55 -0800)]
acpi: check for pxm_to_node_map overflow
It is hardly (if ever) possible but in case of broken _PXM entry we could
reach out of pxm_to_node_map array bounds in acpi_map_pxm_to_node() call.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
Jiri Slaby [Wed, 4 Mar 2009 19:55:27 +0000 (11:55 -0800)]
ACPI: remove doubled status checking
There was a misplaced status test (two consequent tests without a
statement in between) in acpi_bus_init for ages. Remove it, since the
function which should be checked (acpi_os_initialize1) has BUG_ONs on
failure paths.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
Len Brown [Wed, 25 Feb 2009 23:00:18 +0000 (18:00 -0500)]
Revert "ACPI: make some IO ports off-limits to AML"
This reverts commit 5ec5d38a1c8af255ffc481c81eef13e9155524b3.
because it caused spurious dmesg warmings.
We'll implement the check for off-limit ports
in a more clever way in the future.
(Thanks to Al Viro for reminding me of this, via Ingo)
CPU_MASK_ALL is the (deprecated) "all bits set" cpumask, defined as so:
#define CPU_MASK_ALL (cpumask_t) { { ... } }
Taking the address of such a temporary is questionable at best,
unfortunately 321a8e9d (cpumask: add CPU_MASK_ALL_PTR macro) added
CPU_MASK_ALL_PTR:
#define CPU_MASK_ALL_PTR (&CPU_MASK_ALL)
Which formalizes this practice. One day gcc could bite us over this
usage (though we seem to have gotten away with it so far).
So replace everywhere which used &CPU_MASK_ALL or CPU_MASK_ALL_PTR
with the modern "cpu_all_mask" (a real struct cpumask *), and remove
CPU_MASK_ALL_PTR altogether.
Also remove the confusing and deprecated large-NR_CPUS-only
"cpu_mask_all".
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Ingo Molnar <mingo@elte.hu> Reported-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Mike Travis <travis@sgi.com>
Rusty Russell [Mon, 16 Mar 2009 04:10:22 +0000 (14:40 +1030)]
cpumask: arch_send_call_function_ipi_mask: sparc
We're weaning the core code off handing cpumask's around on-stack.
This introduces arch_send_call_function_ipi_mask(), and by defining
it, the old arch_send_call_function_ipi is defined by the core code.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell [Mon, 16 Mar 2009 03:49:37 +0000 (14:19 +1030)]
cpumask: arch_send_call_function_ipi_mask: parisc
We're weaning the core code off handing cpumask's around on-stack.
This introduces arch_send_call_function_ipi_mask(), and by defining
it, the old arch_send_call_function_ipi is defined by the core code.
We also take the chance to change send_IPI_mask() and use the new
for_each_cpu() iterator.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Frans Pop [Wed, 4 Mar 2009 19:55:28 +0000 (11:55 -0800)]
hp-wmi: notify of a potential docking state change on resume
It is possible that the system gets docked or undocked while it's
suspended. Generate an input event on resume to notify user space
if there was a state change.
As it is a switch, we can generate the event unconditionally; the
input layer will only pass it on if there is an actual change.
Signed-off-by: Frans Pop <elendil@planet.nl> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
Ilpo Järvinen [Sat, 14 Mar 2009 14:23:07 +0000 (14:23 +0000)]
tcp: make sure xmit goal size never becomes zero
It's not too likely to happen, would basically require crafted
packets (must hit the max guard in tcp_bound_to_half_wnd()).
It seems that nothing that bad would happen as there's tcp_mems
and congestion window that prevent runaway at some point from
hurting all too much (I'm not that sure what all those zero
sized segments we would generate do though in write queue).
Preventing it regardless is certainly the best way to go.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Sat, 14 Mar 2009 22:45:16 +0000 (22:45 +0000)]
tcp: cache result of earlier divides when mss-aligning things
The results is very unlikely change every so often so we
hardly need to divide again after doing that once for a
connection. Yet, if divide still becomes necessary we
detect that and do the right thing and again settle for
non-divide state. Takes the u16 space which was previously
taken by the plain xmit_size_goal.
This should take care part of the tso vs non-tso difference
we found earlier.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Sat, 14 Mar 2009 14:23:05 +0000 (14:23 +0000)]
tcp: simplify tcp_current_mss
There's very little need for most of the callsites to get
tp->xmit_goal_size updated. That will cost us divide as is,
so slice the function in two. Also, the only users of the
tp->xmit_goal_size are directly behind tcp_current_mss(),
so there's no need to store that variable into tcp_sock
at all! The drop of xmit_goal_size currently leaves 16-bit
hole and some reorganization would again be necessary to
change that (but I'm aiming to fill that hole with u16
xmit_goal_size_segs to cache the results of the remaining
divide to get that tso on regression).
Bring xmit_goal_size parts into tcp.c
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
I toggled the return values of tcp_paws_check around since
the old encoding added yet-another negation making tracking
of truth-values really complicated.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Sat, 14 Mar 2009 14:23:01 +0000 (14:23 +0000)]
tcp: remove pointless .dsack/.num_sacks code
In the pure assignment case, the earlier zeroing is
still in effect.
David S. Miller raised concerns if the ifs are there to avoid
dirtying cachelines. I came to these conclusions:
> We'll be dirty it anyway (now that I check), the first "real" statement
> in tcp_rcv_established is:
>
> tp->rx_opt.saw_tstamp = 0;
>
> ...that'll land on the same dword. :-/
>
> I suppose the blocks are there just because they had more complexity
> inside when they had to calculate the eff_sacks too (maybe it would
> have been better to just remove them in that drop-patch so you would
> have had less head-ache :-)).
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
françois romieu [Sun, 15 Mar 2009 01:10:50 +0000 (01:10 +0000)]
r8169: revert "r8169: read MAC address from EEPROM on init (2nd attempt)"
It fails on the following systems:
- RTL8169sc/8110sc (XID 18000000)
reported by Tim Durack <tdurack@gmail.com> (x86)
- RTL8169sb/8110sb (XID 10000000)
reported by Mikael Pettersson <mikpe@it.uu.se> (ARM)
The patch appeared to work on x86 for the following systems:
RTL8169sb/8110sb 10000000 PCI (EXT)
RTL8110s 04000000 PCI (EXT)
RTL8102e 24a00000 PCI-E (LOM)
RTL8168c/8111c 3c2000c0 PCI-E (LOM)
RTL8168b/8111b 38000000 PCI-E (LOM)
RTL8168b/8111b 38000000 PCI-E (EXT)
The patch exposes two problems:
1) while not completely wrong, mac addresses are not read correctly
from the EEPROM
2) the MAC address registers are not correctly set
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: David S. Miller <davem@davemloft.net>
Jarek Poplawski [Mon, 16 Mar 2009 03:00:19 +0000 (20:00 -0700)]
pkt_sched: Change misleading code in class delete.
While looking for a possible reason of bugzilla report on HTB oops:
http://bugzilla.kernel.org/show_bug.cgi?id=12858
I found the code in htb_delete calling htb_destroy_class on zero
refcount is very misleading: it can suggest this is a common path, and
destroy is called under sch_tree_lock. Actually, this can never happen
like this because before deletion cops->get() is done, and after
delete a class is still used by tclass_notify. The class destroy is
always called from cops->put(), so without sch_tree_lock.
This doesn't mean much now (since 2.6.27) because all vulnerable calls
were moved from htb_destroy_class to htb_delete, but there was a bug
in older kernels. The same change is done for other classful scheds,
which, it seems, didn't have similar locking problems here.
Reported-by: m0sia <m0sia@m0sia.ru> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Mon, 16 Mar 2009 02:59:13 +0000 (19:59 -0700)]
net: reorder fields of struct socket
On x86_64, its rather unfortunate that "wait_queue_head_t wait"
field of "struct socket" spans two cache lines (assuming a 64
bytes cache line in current cpus)
This might explain why Kenny Chang noticed that his multicast workload
was performing bad with 64 bit kernels, since more cache lines ping pongs
were involved.
This litle patch moves "wait" field next "fasync_list" so that both
fields share a single cache line, to speedup sock_def_readable()
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Nicolas Pitre [Fri, 19 Sep 2008 04:36:12 +0000 (00:36 -0400)]
[ARM] add CONFIG_HIGHMEM option
Here it is... HIGHMEM for the ARM architecture. :-)
If you don't have enough ram for highmem pages to be allocated and still
want to test this, then the cmdline option "vmalloc=" can be used with
a value large enough to force the highmem threshold down.
Successfully tested on a Marvell DB-78x00-BP Development Board with
2 GB of RAM.
Nicolas Pitre [Tue, 4 Nov 2008 05:48:42 +0000 (00:48 -0500)]
[ARM] ignore high memory with VIPT aliasing caches
VIPT aliasing caches have issues of their own which are not yet handled.
Usage of discard_old_kernel_data() in copypage-v6.c is not highmem ready,
kmap/fixmap stuff doesn't take account of cache colouring, etc.
If/when those issues are handled then this could be reverted.
Nicolas Pitre [Fri, 19 Sep 2008 02:55:47 +0000 (22:55 -0400)]
[ARM] xsc3: add highmem support to L2 cache handling code
On xsc3, L2 cache ops are possible only on virtual addresses. The code
is rearranged so to have a linear progression requiring the least amount
of pte setups in the highmem case. To protect the virtual mapping so
created, interrupts must be disabled currently up to a page worth of
address range.
The interrupt disabling is done in a way to minimize the overhead within
the inner loop. The alternative would consist in separate code for
the highmem and non highmem compilation which is less preferable.
Nicolas Pitre [Fri, 12 Sep 2008 20:11:51 +0000 (16:11 -0400)]
[ARM] Feroceon: add highmem support to L2 cache handling code
The choice is between looping over the physical range and performing
single cache line operations, or to map highmem pages somewhere, as
cache range ops are possible only on virtual addresses.
Because L2 range ops are much faster, we go with the later by factoring
the physical-to-virtual address conversion and use a fixmap entry for it
in the HIGHMEM case.
Possible future optimizations to avoid the pte setup cost:
- do the pte setup for highmem pages only
- determine a threshold for doing a line-by-line processing on physical
addresses when the range is small