Now that ptep_establish has a definition in PAE i386 3-level paging code, the
only paging model which is insane enough to have multi-word hardware PTEs
which are not efficient to set atomically, we can remove the ghost of
set_pte_atomic from other architectures which falesly duplicated it, and
remove all knowledge of it from the generic pgtable code.
set_pte_atomic is now a private pte operator which is specific to i386
Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The ptep_establish macro is only used on user-level PTEs, for P->P mapping
changes. Since these always happen under protection of the pagetable lock,
the strong synchronization of a 64-bit cmpxchg is not needed, in fact, not
even a lock prefix needs to be used. We can simply instead clear the P-bit,
followed by a normal set. The write ordering is still important to avoid the
possibility of the TLB snooping a partially written PTE and getting a bad
mapping installed.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create a new PTE function which combines clearing a kernel PTE with the
subsequent flush. This allows the two to be easily combined into a single
hypercall or paravirt-op. More subtly, reverse the order of the flush for
kmap_atomic. Instead of flushing on establishing a mapping, flush on clearing
a mapping. This eliminates the possibility of leaving stale kmap entries
which may still have valid TLB mappings. This is required for direct mode
hypervisors, which need to reprotect all mappings of a given page when
changing the page type from a normal page to a protected page (such as a page
table or descriptor table page). But it also provides some nicer semantics
for real hardware, by providing extra debug-proofing against using stale
mappings, as well as ensuring that no stale mappings exist when changing the
cacheability attributes of a page, which could lead to cache conflicts when
two different types of mappings exist for the same page.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove ptep_test_and_clear_{dirty|young} from i386, and instead use the
dominating functions, ptep_clear_flush_{dirty|young}. This allows the TLB
page flush to be contained in the same macro, and allows for an eager
optimization - if reading the PTE initially returned dirty/accessed, we can
assume the fact that no subsequent update to the PTE which cleared accessed /
dirty has occurred, as the only way A/D bits can change without holding the
page table lock is if a remote processor clears them. This eliminates an
extra branch which came from the generic version of the code, as we know that
no other CPU could have cleared the A/D bit, so the flush will always be
needed.
We still export these two defines, even though we do not actually define
the macros in the i386 code:
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
The reason for this is that the only use of these functions is within the
generic clear_flush functions, and we want a strong guarantee that there
are no other users of these functions, so we want to prevent the generic
code from defining them for us.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Implement lazy MMU update hooks which are SMP safe for both direct and shadow
page tables. The idea is that PTE updates and page invalidations while in
lazy mode can be batched into a single hypercall. We use this in VMI for
shadow page table synchronization, and it is a win. It also can be used by
PPC and for direct page tables on Xen.
For SMP, the enter / leave must happen under protection of the page table
locks for page tables which are being modified. This is because otherwise,
you end up with stale state in the batched hypercall, which other CPUs can
race ahead of. Doing this under the protection of the locks guarantees the
synchronization is correct, and also means that spurious faults which are
generated during this window by remote CPUs are properly handled, as the page
fault handler must re-check the PTE under protection of the same lock.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change pte_clear_full to a more appropriately named pte_clear_not_present,
allowing optimizations when not-present mapping changes need not be reflected
in the hardware TLB for protected page table modes. There is also another
case that can use it in the fremap code.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A new member in the ever growing family of call_usermode* functions is
born. The new call_usermodehelper_pipe() function allows to pipe data to
the stdin of the called user mode progam and behaves otherwise like the
normal call_usermodehelp() (except that it always waits for the child to
finish)
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Split the big and hard to read do_pipe function into smaller pieces.
This creates new create_write_pipe/free_write_pipe/create_read_pipe
functions. These functions are made global so that they can be used by
other parts of the kernel.
The resulting code is more generic and easier to read and has cleaner error
handling and less gotos.
[akpm@osdl.org: cleanup]
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds a generic implementation of ioremap_page_range() in
lib/ioremap.c based on the i386 implementation. It differs from the
i386 version in the following ways:
* The PTE flags are passed as a pgprot_t argument and must be
determined up front by the arch-specific code. No additional
PTE flags are added.
* Uses set_pte_at() instead of set_pte()
[bunk@stusta.de: warning fix]
]dhowells@redhat.com: nommu build fix]
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Andi Kleen <ak@suse.de>
Cc: <linux-m32r@ml.linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@parisc-linux.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is a the first of a series of patch-sets aiming at making kdump more
robust against stack overflows.
This patch set does the following:
* Add safe_smp_processor_id function to i386 architecture (this function was
inspired by the x86_64 function of the same name).
* Substitute "smp_processor_id" with the stack overflow-safe
"safe_smp_processor_id" in the reboot path to the second kernel.
This patch:
On the event of a stack overflow critical data that usually resides at the
bottom of the stack is likely to be stomped and, consequently, its use should
be avoided.
In particular, in the i386 and IA64 architectures the macro smp_processor_id
ultimately makes use of the "cpu" member of struct thread_info which resides
at the bottom of the stack. x86_64, on the other hand, is not affected by
this problem because it benefits from the use of the PDA infrastructure.
To circumvent this problem I suggest implementing "safe_smp_processor_id()"
(it already exists in x86_64) for i386 and IA64 and use it as a replacement
for smp_processor_id in the reboot path to the dump capture kernel. This is a
possible implementation for i386.
Signed-off-by: Fernando Vazquez <fernando@intellilink.co.jp>
Looks-reasonable-to: Andi Kleen <ak@muc.de>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some filesystems, instead of simply decrementing i_nlink, simply zero it
during an unlink operation. We need to catch these in addition to the
decrement operations.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is mostly included for parity with dec_nlink(), where we will have some
more hooks. This one should stay pretty darn straightforward for now.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When a filesystem decrements i_nlink to zero, it means that a write must be
performed in order to drop the inode from the filesystem.
We're shortly going to have keep filesystems from being remounted r/o between
the time that this i_nlink decrement and that write occurs.
So, add a little helper function to do the decrements. We'll tie into it in a
bit to note when i_nlink hits zero.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ChangeLog:
Feedbacks from Andrew Morton:
- define TS_COMM_LEN to 32
- change acct_stimexpd field of task_struct to be of
cputime_t, which is to be used to save the tsk->stime
of last timer interrupt update.
- a new Documentation/accounting/taskstats-struct.txt
to describe fields of taskstats struct.
Feedback from Balbir Singh:
- keep the stime of a task to be zero when both stime
and utime are zero as recoreded in task_struct.
Misc:
- convert accumulated RSS/VM from platform dependent
pages-ticks to MBytes-usecs in the kernel
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There were a few accounting data/macros that are used in CSA but are #ifdef'ed
inside CONFIG_BSD_PROCESS_ACCT. This patch is to change those ifdef's from
CONFIG_BSD_PROCESS_ACCT to CONFIG_TASK_XACCT. A few defines are moved from
kernel/acct.c and include/linux/acct.h to kernel/tsacct.c and
include/linux/tsacct_kern.h.
Signed-off-by: Jay Lan <jlan@sgi.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add extended system accounting handling over taskstats interface. A
CONFIG_TASK_XACCT flag is created to enable the extended accounting code.
Signed-off-by: Jay Lan <jlan@sgi.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add some basic accounting fields to the taskstats struct, add a new
kernel/tsacct.c to handle basic accounting data handling upon exit. A handle
is added to taskstats.c to invoke the basic accounting data handling.
Signed-off-by: Jay Lan <jlan@sgi.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Cc: "Michal Piotrowski" <michal.k.k.piotrowski@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add two utility helper functions genlmsg_msg_size() and genlmsg_total_size().
These functions are derived from their netlink counterparts.
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jamal Hadi <hadi@cyberus.ca>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This work is initially done by Zach Brown to add support for vectored aio.
These are the core changes for AIO to support
IOCB_CMD_PREADV/IOCB_CMD_PWRITEV.
[akpm@osdl.org: huge build fix]
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch cleans up generic_file_*_read/write() interfaces. Christoph
Hellwig gave me the idea for this clean ups.
In a nutshell, all filesystems should set .aio_read/.aio_write methods and use
do_sync_read/ do_sync_write() as their .read/.write methods. This allows us
to cleanup all variants of generic_file_* routines.
Final available interfaces:
generic_file_aio_read() - read handler
generic_file_aio_write() - write handler
generic_file_aio_write_nolock() - no lock write handler
__generic_file_aio_write_nolock() - internal worker routine
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes readv() and writev() methods and replaces them with
aio_read()/aio_write() methods.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch vectorizes aio_read() and aio_write() methods to prepare for
collapsing all aio & vectored operations into one interface - which is
aio_read()/aio_write().
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Michael Holzheu <HOLZHEU@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is the patch the three previous ones have been leading up to.
It changes the behavior of ReiserFS from loading and caching all the bitmaps
as special, to treating the bitmaps like any other bit of metadata and just
letting the system-wide caches figure out what to hang on to.
Buffer heads are allocated on the fly, so there is no need to retain pointers
to all of them. The caching of the metadata occurs when the data is read and
updated, and is considered invalid and uncached until then.
I needed to remove the vs-4040 check for performing a duplicate operation on a
particular bit. The reason is that while the other sites for working with
bitmaps are allowed to schedule, is_reusable() is called from do_balance(),
which will panic if a schedule occurs in certain places.
The benefit of on-demand bitmaps clearly outweighs a sanity check that depends
on a compile-time option that is discouraged.
[akpm@osdl.org: warning fix]
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch moves the bitmap loading code from super.c to bitmap.c
The code is also restructured somewhat. The only difference between new
format bitmaps and old format bitmaps is where they are. That's a two liner
before loading the block to use the correct one. There's no need for an
entirely separate code path.
The load path is generally the same, with the pattern being to throw out a
bunch of requests and then wait for them, then cache the metadata from the
contents.
Again, like the previous patches, the purpose is to set up for later ones.
Update: There was a bug in the previously posted version of this that resulted
in corruption. The problem was that bitmap 0 on new format file systems must
be treated specially, and wasn't. A stupid bug with an easy fix.
This is hopefully the last fix for the disaster that is the reiserfs bitmap
patch set.
If a bitmap block was full, first_zero_hint would end up at zero since it
would never be changed from it's zeroed out value. This just sets it
beyond the end of the bitmap block. If any bits are freed, it will be
reset to a valid bit. When info->free_count = 0, then we already know it's
full.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There is a check in is_reusable to determine if a particular block is a bitmap
block. It verifies this by going through the array of bitmap block buffer
heads and comparing the block number to each one.
Bitmap blocks are at defined locations on the disk in both old and current
formats. Simply checking against the known good values is enough.
This is a trivial optimization for a non-production codepath, but this is the
first in a series of patches that will ultimately remove the buffer heads from
that array.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With 2.6.18-rc4-mm2, now wall_jiffies will always be the same as jiffies.
So we can kill wall_jiffies completely.
This is just a cleanup and logically should not change any real behavior
except for one thing: RTC updating code in (old) ppc and xtensa use a
condition "jiffies - wall_jiffies == 1". This condition is never met so I
suppose it is just a bug. I just remove that condition only instead of
kill the whole "if" block.
[heiko.carstens@de.ibm.com: s390 build fix and cleanup]
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Andi Kleen <ak@muc.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Hirokazu Takata <takata.hirokazu@renesas.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Chris Zankel <chris@zankel.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch contains the following possible cleanups:
- make the following needlessly global function static:
- ntp_update_frequency()
- make the following needlessly global variables static:
- time_state
- time_offset
- time_constant
- time_reftime
- remove the following read-only global variable:
- time_precision
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove a few unused defines and remove obsolete information from comments.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This converts the kernel ntp model into a model which matches the nanokernel
reference implementations. The previous patches already increased the
resolution and precision of the computations, so that this conversion becomes
quite simple.
<linux@horizon.com> explains:
The original NTP kernel interface was defined in units of microseconds.
That's what Linux implements. As computers have gotten faster and can now
split microseconds easily, a new kernel interface using nanosecond units was
defined ("the nanokernel", confusing as that name is to OS hackers), and
there's an STA_NANO bit in the adjtimex() status field to tell the application
which units it's using.
The current ntpd supports both, but Linux loses some possible timing
resolution because of quantization effects, and the ntpd hackers would really
like to be able to drop the backwards compatibility code.
Ulrich Windl has been maintaining a patch set to do the conversion for years,
but it's hard to keep in sync.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This converts time_freq to a scaled nsec value and adds around 6bit of extra
resolution. This pushes the time_freq to its 32bit limits so the calculatons
have to be done with 64bit.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
time_tolerance isn't changed at all in the kernel, so simply remove it, this
simplifies the next patch, as it avoids a number of conversions.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This folds update_ntp_one_tick() into second_overflow() and adds time_adjust
to the tick length, this makes time_next_adjust unnecessary. This slightly
changes the adjtime() behaviour, instead of applying it to the next tick, it's
applied to the next second.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This converts time_offset into a scaled per tick value. This avoids now
completely the crude compensation in second_overflow().
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This introduces ntp_update_frequency() and deinlines ntp_clear() (as it's not
performance critical). ntp_update_frequency() calculates the base tick length
using tick_usec and adds a base adjustment, in case the frequency doesn't
divide evenly by HZ.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move all the NTP related code to ntp.c
[akpm@osdl.org: cleanups, build fix]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The lock annotation macros __acquires, __releases, __acquire, and __release
all currently throw away the lock expression passed as an argument. Now
that sparse can parse __context__ and __attribute__((context)) with a
context expression, pass the lock expression down to sparse as the context
expression. This requires a version of sparse from GIT commit
37475a6c1c3e66219e68d912d5eb833f4098fd72 or later.
Signed-off-by: Josh Triplett <josh@freedesktop.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Update RTC framework so that drivers can constify their method tables, moving
them from ".data" to ".rodata". Then update the drivers.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
BUG_ON() does this unlikely check itself, as bugs in Linux are unlikely
anyway :)
Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Acked-by: Zach Brown <zach.brown@oracle.com>
Acked-by: Benjamin LaHaise <benjamin.c.lahaise@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ppc can boot one single binary on prep, chrp and pmac boards. ppc64 can
boot one single binary on pseries and G5 boards. pmac has no legacy io,
probing for PC style legacy hardware (or accessing the legacy io area
regulary) may lead to a hard crash:
* add check for parport_pc, exit on pmac. 32bit chrp has no
->check_legacy_ioport, the probe is always called. 64bit chrp has
check_legacy_ioport, check for a "parallel" node
* add check for isapnp, only PReP boards may have real ISA slots. 32bit
PReP will have no ->check_legacy_ioport, the probe is always called.
* update code in i8042_platform_init. Run ->check_legacy_ioport first,
always call request_region. No functional change. Remove whitespace
before i8042_reset init.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds the ability to register for a command per-channel in the
IPMI driver.
If your BMC supports multiple channels, incoming messages can be useful to
have the ability to register to receive commands on a specific channel
instead the current behaviour of all channels.
Signed-off-by: David Barksdale <amatus@ocgnet.org>
Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The ncp specific compat ioctls are clearly local to one file system, so the
code can better live there.
This version of the patch moves everything into the generic ioctl handler
and uses it for both 32 and 64 bit calls.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Prevent multiple inclusions of include/linux/sysrq.h using traditional
#ifndef..#endif.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@enix.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove unused global SYSRQ_KEY from ppc and powerpc
Remove unused define SYSRQ_KEY from sh/sh64 and h8300
Remove unused pckbd_sysrq_xlate and kbd_sysrq_xlate usage
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add bisync and monosync serial protocol support to the synclink_gt driver.
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the new diagnose 0x9c in the spinlock implementation for s390. It
yields the remaining timeslice of the virtual cpu that tries to acquire a
lock to the virtual cpu that is the current holder of the lock.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Powerpc already has a directed yield for CONFIG_PREEMPT="n". To make it
work with CONFIG_PREEMPT="y" as well the _raw_{spin,read,write}_relax
primitives need to be defined to call __spin_yield() for spinlocks and
__rw_yield() for rw-locks.
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On systems running with virtual cpus there is optimization potential in
regard to spinlocks and rw-locks. If the virtual cpu that has taken a lock
is known to a cpu that wants to acquire the same lock it is beneficial to
yield the timeslice of the virtual cpu in favour of the cpu that has the
lock (directed yield).
With CONFIG_PREEMPT="n" this can be implemented by the architecture without
common code changes. Powerpc already does this.
With CONFIG_PREEMPT="y" the lock loops are coded with _raw_spin_trylock,
_raw_read_trylock and _raw_write_trylock in kernel/spinlock.c. If the lock
could not be taken cpu_relax is called. A directed yield is not possible
because cpu_relax doesn't know anything about the lock. To be able to
yield the lock in favour of the current lock holder variants of cpu_relax
for spinlocks and rw-locks are needed. The new _raw_spin_relax,
_raw_read_relax and _raw_write_relax primitives differ from cpu_relax
insofar that they have an argument: a pointer to the lock structure.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
One of idiomatic ways to duplicate a region of memory is
dst = kmalloc(len, GFP_KERNEL);
if (!dst)
return -ENOMEM;
memcpy(dst, src, len);
which is neat code except a programmer needs to write size twice. Which
sometimes leads to mistakes. If len passed to kmalloc is smaller that len
passed to memcpy, it's straight overwrite-beyond-end. If len passed to
memcpy is smaller than len passed to kmalloc, it's either a) legit
behaviour ;-), or b) cloned buffer will contain garbage in second half.
Slight trolling of commit lists shows several duplications bugs
done exactly because of diverged lenghts:
Linux:
[CRYPTO]: Fix memcpy/memset args.
[PATCH] memcpy/memset fixes
OpenBSD:
kerberosV/src/lib/asn1: der_copy.c:1.4
If programmer is given only one place to play with lengths, I believe, such
mistakes could be avoided.
With kmemdup, the snippet above will be rewritten as:
dst = kmemdup(src, len, GFP_KERNEL);
if (!dst)
return -ENOMEM;
This also leads to smaller code (kzalloc effect). Quick grep shows
200+ places where kmemdup() can be used.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
