To keep the dcache from filling up with dead /proc entries we flush them on
process exit. However over the years that code has gotten hairy with a
dentry_pointer and a lock in task_struct and misdocumented as a correctness
feature.
I have rewritten this code to look and see if we have a corresponding entry in
the dcache and if so flush it on process exit. This removes the extra fields
in the task_struct and allows me to trivially handle the case of a
/proc/<tgid>/task/<pid> entry as well as the current /proc/<pid> entries.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
All of the functions for proc_maps_operations are already defined in
task_mmu.c so move the operations structure to keep the functionality
together.
Since task_nommu.c implements a dummy version of /proc/<pid>/maps give it a
simplified version of proc_maps_operations that it can modify to best suit its
needs.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use getattr to get an accurate link count when needed. This is cheaper and
more accurate than trying to derive it by walking the thread list of a
process.
Especially as it happens when needed stat instead of at readdir time.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Long ago and far away in 2.2 we started checking to ensure the files we
displayed in /proc were visible to the current process. It was an
unsophisticated time and no one was worried about functions full of FIXMES in
a stable kernel. As time passed the function became sacred and was enshrined
in the shrine of how things have always been. The fixes came in but only to
keep the function working no one really remembering or documenting why we did
things that way.
The intent and the functionality make a lot of sense. Don't let /proc be an
access point for files a process can see no other way. The implementation
however is completely wrong.
We are currently checking the root directories of the two processes, we are
not checking the actual file descriptors themselves.
We are strangely checking with a permission method instead of just when we use
the data.
This patch fixes the logic to actually check the file descriptors and make a
note that implementing a permission method for this part of /proc almost
certainly indicates a bug in the reasoning.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The inode operations only exist to support the proc_permission function.
Currently mem_read and mem_write have all the same permission checks as
ptrace. The fs check makes no sense in this context, and we can trivially get
around it by calling ptrace.
So simply the code by killing the strange weird case.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
First we can access every /proc/<tgid>/task/<pid> directory as /proc/<pid> so
proc_task_permission is not usefully limiting visibility.
Second having related filesystems information should have nothing to do with
process visibility. kill does not implement any checks like that.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The sole renaming use of proc_inode.type is to discover the file descriptor
number, so just store the file descriptor number and don't wory about
processing this field. This removes any /proc limits on the maximum number of
file descriptors, and clears the path to make the hard coded /proc inode
numbers go away.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently in /proc if the task is dumpable all of files are owned by the tasks
effective users. Otherwise the files are owned by root. Unless it is the
/proc/<tgid>/ or /proc/<tgid>/task/<pid> directory in that case we always make
the directory owned by the effective user.
However the special case for directories is pointless except as a way to read
the effective user, because the permissions on both of those directories are
world readable, and executable.
/proc/<tgid>/status provides a much better way to read a processes effecitve
userid, so it is silly to try to provide that on the directory.
So this patch simplifies the code by removing a pointless special case and
gets us one step closer to being able to remove the hard coded /proc inode
numbers.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The removed fields are already set by proc_alloc_inode. Initializing them in
proc_alloc_inode implies they need it for proper cleanup. At least ei->pde
was not set on all paths making it look like proc_alloc_inode was buggy. So
just remove the redundant assignments.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We already call everything except do_proc_readlink outside of the BKL in
proc_pid_followlink, and there appears to be nothing in do_proc_readlink that
needs any special protection.
So remove this leftover from one of the BKL cleanup efforts.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I noticed recently that my CONFIG_CRYPTO_MD5 turned into a y again instead
of m. It turns out that CONFIG_NFSD_V4 is selecting it to be y even though
I've chosen to compile nfsd as a module.
In general when we have a bool sitting under a tristate it is better to
select things you need from the tristate rather than the bool since that
allows the things you select to be modules.
The following patch does it for nfsd.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add the IOCTLs of the Gigaset drivers to compat_ioctl.h in order to make
them available for 32 bit programs on 64 bit platforms. Please merge.
Signed-off-by: Hansjoerg Lipp <hjlipp@web.de>
Acked-by: Tilman Schmidt <tilman@imap.cc>
Cc: Karsten Keil <kkeil@suse.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch to the common part of the Siemens Gigaset driver
prevents it from trying to send the +++ break sequence if the device has
been disconnected, and removes a couple of assignments which didn't have
any effect.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Acked-by: Hansjoerg Lipp <hjlipp@web.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch to the Siemens Gigaset base driver adds graceful
recovery for some frequently encountered error conditions, by retrying
failed control requests (eg. stalled control pipe), and by closing and
reopening the AT command channel when it appears to be stuck.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Acked-by: Hansjoerg Lipp <hjlipp@web.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This fixes coverity bug #517.
Since IESIZE is greater than IESIZE_NI1 we might run past the end of
ielist_ni1. This fixes it by using the proper IESIZE_NI1 define.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I am getting more or less reproducible crashes from the CAPI subsystem
using the fcdsl driver:
Unable to handle kernel NULL pointer dereference at virtual address 00000010
printing eip:
c39bbca4
*pde = 00000000
Oops: 0000 [#1]
Modules linked in: netconsole capi capifs 3c59x mii fcdsl kernelcapi uhci_hcd usbcore ide_cd cdrom
CPU: 0
EIP: 0060:[<c39bbca4>] Tainted: P VLI
EFLAGS: 00010202 (2.6.16.11 #3)
EIP is at handle_minor_send+0x17a/0x241 [capi]
eax: c24abbc0 ebx: c0b4c980 ecx: 00000010 edx: 00000010
esi: c1679140 edi: c2783016 ebp: 0000c28d esp: c0327e24
ds: 007b es: 007b ss: 0068
Process swapper (pid: 0, threadinfo=c0326000 task=c02e1300)
Stack: <0>000005b4 c1679180 00000000 c28d0000 c1ce04e0 c2f69654 c221604e c1679140
c39bc19a 00000038 c20c0400 c075c560 c1f2f800 00000000 c01dc9b5 c1e96a40
c075c560 c2ed64c0 c1e96a40 c01dcd3b c2fb94e8 c075c560 c0327f00 c1e96a40
Call Trace:
[<c39bc19a>] capinc_tty_write+0xda/0xf3 [capi]
[<c01dc9b5>] ppp_sync_push+0x52/0xfe
[<c01dcd3b>] ppp_sync_send+0x1f5/0x204
[<c01d9bc1>] ppp_push+0x3e/0x9c
[<c01dacd4>] ppp_xmit_process+0x422/0x4cc
[<c01daf3f>] ppp_start_xmit+0x1c1/0x1f6
[<c0213ea5>] qdisc_restart+0xa7/0x135
[<c020b112>] dev_queue_xmit+0xba/0x19e
[<c0223f69>] ip_output+0x1eb/0x236
[<c0220907>] ip_forward+0x1c1/0x21a
[<c021fa6c>] ip_rcv+0x38e/0x3ea
[<c020b4c2>] netif_receive_skb+0x166/0x195
[<c020b55e>] process_backlog+0x6d/0xd2
[<c020a30f>] net_rx_action+0x6a/0xff
[<c0112909>] __do_softirq+0x35/0x7d
[<c0112973>] do_softirq+0x22/0x26
[<c0103a9d>] do_IRQ+0x1e/0x25
[<c010255a>] common_interrupt+0x1a/0x20
[<c01013c5>] default_idle+0x2b/0x53
[<c0101426>] cpu_idle+0x39/0x4e
[<c0328386>] start_kernel+0x20b/0x20d
Code: c0 e8 b3 b6 77 fc 85 c0 75 10 68 d8 c8 9b c3 e8 82 3d 75 fc 8b 43 60 5a eb 50 8d 56 50 c7 00 00 00 00 00 66 89 68 04 eb 02 89
ca <8b> 0a 85 c9 75 f8 89 02 89 da ff 46 54 8b 46 10 e8 30 79 fd ff
<0>Kernel panic - not syncing: Fatal exception in interrupt
That oops took me to the "ackqueue" implementation in capi.c. The crash
occured in capincci_add_ack() (auto-inlined by the compiler).
I read the code a bit and finally decided to replace the custom linked list
implementation (struct capiminor->ackqueue) by a struct list_head. That
did not solve the crash, but produced the following interresting oops:
Unable to handle kernel paging request at virtual address 00200200
printing eip:
c39bb1f5
*pde = 00000000
Oops: 0002 [#1]
Modules linked in: netconsole capi capifs 3c59x mii fcdsl kernelcapi uhci_hcd usbcore ide_cd cdrom
CPU: 0
EIP: 0060:[<c39bb1f5>] Tainted: P VLI
EFLAGS: 00010246 (2.6.16.11 #3)
EIP is at capiminor_del_ack+0x18/0x49 [capi]
eax: 00200200 ebx: c18d41a0 ecx: c1385620 edx: 00100100
esi: 0000d147 edi: 00001103 ebp: 0000d147 esp: c1093f3c
ds: 007b es: 007b ss: 0068
Process events/0 (pid: 3, threadinfo=c1092000 task=c1089030)
Stack: <0>c2a17580 c18d41a0 c39bbd16 00000038 c18d41e0 00000000 d147c640 c29e0b68
c29e0b90 00000212 c29e0b68 c39932b2 c29e0bb0 c10736a0 c0119ef0 c399326c
c10736a8 c10736a0 c10736b0 c0119f93 c011a06e 00000001 00000000 00000000
Call Trace:
[<c39bbd16>] handle_minor_send+0x1af/0x241 [capi]
[<c39932b2>] recv_handler+0x46/0x5f [kernelcapi]
[<c0119ef0>] run_workqueue+0x5e/0x8d
[<c399326c>] recv_handler+0x0/0x5f [kernelcapi]
[<c0119f93>] worker_thread+0x0/0x10b
[<c011a06e>] worker_thread+0xdb/0x10b
[<c010c998>] default_wake_function+0x0/0xc
[<c011c399>] kthread+0x90/0xbc
[<c011c309>] kthread+0x0/0xbc
[<c0100a65>] kernel_thread_helper+0x5/0xb
Code: 7e 02 89 ee 89 f0 5a f7 d0 c1 f8 1f 5b 21 f0 5e 5f 5d c3 56 53 8b 48 50 89 d6 89 c3 8b 11 eb 2f 66 39 71 08 75 25 8b 41 04 8b 11 <89> 10 89 42 04 c7 01 00 01 10 00 89 c8 c7 41 04 00 02 20 00 e8
The interresting part of it is the "virtual address 00200200", which is
LIST_POISON2. I thought about some race condition, but as this is an UP
system, it leads to questions on how it can happen. If we look at EFLAGS:
00010202, we see that interrupts are enabled at the time of the crash
(eflags & 0x200).
Finally, I don't understand all the capi code, but I think that
handle_minor_send() is racing somehow against capi_recv_message(), which
call both capiminor_del_ack(). So if an IRQ occurs in the middle of
capiminor_del_ack() and another instance of it is invoked, it leads to
linked list corruption.
I came up with the following patch. With this, I could not reproduce the
crash anymore. Clearly, this is not the correct fix for the issue. As this
seems to be some locking issue, there might be more locking issues in that
code. For example, doesn't the whole struct capiminor have to be locked
somehow?
Cc: Carsten Paeth <calle@calle.de>
Cc: Kai Germaschewski <kai.germaschewski@gmx.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With this patch Kprobes now registers for page fault notifications only when
their is an active probe registered. Once all the active probes are
unregistered their is no need to be notified of page faults and kprobes
unregisters itself from the page fault notifications. Hence we will have ZERO
side effects when no probes are active.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Kprobes now registers for page fault notifications.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavmurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Overloading of page fault notification with the notify_die() has performance
issues(since the only interested components for page fault is kprobes and/or
kdb) and hence this patch introduces the new notifier call chain exclusively
for page fault notifications their by avoiding notifying unnecessary
components in the do_page_fault() code path.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Overloading of page fault notification with the notify_die() has performance
issues(since the only interested components for page fault is kprobes and/or
kdb) and hence this patch introduces the new notifier call chain exclusively
for page fault notifications their by avoiding notifying unnecessary
components in the do_page_fault() code path.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Overloading of page fault notification with the notify_die() has performance
issues(since the only interested components for page fault is kprobes and/or
kdb) and hence this patch introduces the new notifier call chain exclusively
for page fault notifications their by avoiding notifying unnecessary
components in the do_page_fault() code path.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Overloading of page fault notification with the notify_die() has performance
issues(since the only interested components for page fault is kprobes and/or
kdb) and hence this patch introduces the new notifier call chain exclusively
for page fault notifications their by avoiding notifying unnecessary
components in the do_page_fault() code path.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently in the do_page_fault() code path, we call notify_die(DIE_PAGE_FAULT,
...) to notify the page fault. Since notify_die() is highly overloaded, this
page fault notification is currently being sent to all the components
registered with register_die_notification() which uses the same die_chain to
loop for all the registered components which is unnecessary.
In order to optimize the do_page_fault() code path, this critical page fault
notification is now moved to different call chain and the test results showed
great improvements.
And the kprobes which is interested in this notifications, now registers onto
this new call chain only when it need to, i.e Kprobes now registers for page
fault notification only when their are an active probes and unregisters from
this page fault notification when no probes are active.
I have incorporated all the feedback given by Ananth and Keith and everyone,
and thanks for all the review feedback.
This patch:
Overloading of page fault notification with the notify_die() has performance
issues(since the only interested components for page fault is kprobes and/or
kdb) and hence this patch introduces the new notifier call chain exclusively
for page fault notifications their by avoiding notifying unnecessary
components in the do_page_fault() code path.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If there are multi kprobes on the same probepoint, there will be one extra
aggr_kprobe on the head of kprobe list. The aggr_kprobe has
aggr_post_handler/aggr_break_handler whether the other kprobe
post_hander/break_handler is NULL or not. This patch modifies this, only
when there is one or more kprobe in the list whose post_handler is not
NULL, post_handler of aggr_kprobe will be set as aggr_post_handler.
[soshima@redhat.com: !CONFIG_PREEMPT fix]
Signed-off-by: bibo, mao <bibo.mao@intel.com>
Cc: Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Yumiko Sugita <sugita@sdl.hitachi.co.jp>
Cc: Hideo Aoki <haoki@redhat.com>
Signed-off-by: Satoshi Oshima <soshima@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Previous kprobe-booster patch has not handled any 2byte opcodes and
prefixes. I checked whole IA32 opcode map and classified it.
This patch enables kprobe to boost those 2byte opcodes and prefixes.
Signed-off-by: Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Yumiko Sugita <sugita@sdl.hitachi.co.jp>
Cc: Satoshi Oshima <soshima@redhat.com>
Cc: Hideo Aoki <haoki@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a GTOD clocksource driver based on the Geode SCx200's Hi-Res Timer.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
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>
This fixes the clock source updates in update_wall_time() to correctly
track the time coming in via current_tick_length(). Optimize the fast
paths to be as short as possible to keep the overhead low.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Acked-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Here is the PIT fix against the TOD patches that Tim pointed out. Many
thanks to Tim for hunting this down.
Cc: Tim Mann <mann@vmware.com>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a CLOCKSOURCE_MASK macro to simplify initializing the mask for a struct
clocksource, and use it to replace literal mask constants in the various
clocksource drivers.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- written on init only, accessed for every timer read --> __read_mostly
- fix broken sentence
Signed-off-by: Andreas Mohr <andi@lisas.de>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As suggested by Roman Zippel, change clocksource functions to use
clocksource_xyz rather then xyz_clocksource to avoid polluting the
namespace.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Implement the time sources for i386 (acpi_pm, cyclone, hpet, pit, and tsc).
With this patch, the conversion of the i386 arch to the generic timekeeping
code should be complete.
The patch should be fairly straight forward, only adding the new clocksources.
[hirofumi@mail.parknet.co.jp: acpi_pm cleanup]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove the old timers/timer_opts infrastructure which has been disabled. It
is a fairly straightforward set of deletions
Note that this does not provide any i386 clocksources, so you will only have
the jiffies clocksource. To get full replacements for the code being removed
here, the timeofday-clocks-i386 patch will be needed.
Signed-off-by: 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 i386 arch to use the generic timeofday subsystem. It
enabled the GENERIC_TIME option, disables the timer_opts code and other arch
specific timekeeping code and reworks the delay code.
While this patch enables the generic timekeeping, please note that this patch
does not provide any i386 clocksource. Thus only the jiffies clocksource will
be available. To get full replacements for the code being disabled here, the
timeofday-clocks-i386 patch will needed.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As part of the i386 conversion to the generic timekeeping infrastructure, this
introduces a new tsc.c file. The code in this file replaces the TSC
initialization, management and access code currently in timer_tsc.c (which
will be removed) that we want to preserve.
The code also introduces the following functionality:
o tsc_khz: like cpu_khz but stores the TSC frequency on systems that do not
change TSC frequency w/ CPU frequency
o check/mark_tsc_unstable: accessor/modifier flag for TSC timekeeping
usability
o minor cleanups to calibration math.
This patch also includes a one line __cpuinitdata fix from Zwane Mwaikambo.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A simple cleanup for the i386 arch in preparation of moving to the generic
timeofday infrastructure. It simply moves the PIT initialization code, locks,
and other code we want to keep from some code from timer_pit.c (which will be
removed) to i8253.c.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
John's about to nuke x86's monotonic clock without grepping for it first. The
patch lamely borrows the ppc64 code for x86.
hangcheck-timer shouldn't be doing it this way
a) HAVE_MONOTONIC should be CONFIG_MONOTONIC_CLOCK and it should be defined
in arch/xxx/Kconfig.
b) That ifdef tangle shouldn't be in hangcheck-timer.c. It should be using
arch-provided helper functions, which CONFIG_MONOTONIC_CLOCK-enabling
architectures implement in arch/something.c
Cc: john stultz <johnstul@us.ibm.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Introduces clocksource switching code and the arch generic time accessor
functions that use the clocksource infrastructure.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Instead of incrementing xtime by tick_nsec + ntp adjustments, use the
clocksource abstraction to increment and scale time. Using the clocksource
abstraction allows other clocksources to be used consistently in the face of
late or lost ticks, while preserving the existing behavior via the jiffies
clocksource.
This removes the need to keep time_phase adjustments as we just use the
current_tick_length() function as the NTP interface and accumulate time using
shifted nanoseconds.
The basics of this design was by Roman Zippel, however it is my own
interpretation and implementation, so the credit should go to him and the
blame to me.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change the current_tick_length() function so it takes an argument which
specifies how much precision to return in shifted nanoseconds. This provides
a simple way to convert between NTPs internal nanoseconds shifted by
(SHIFT_SCALE - 10) to other shifted nanosecond units that are used by the
clocksource abstraction.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Modify the update_wall_time function so it increments time using the
clocksource abstraction instead of jiffies. Since the only clocksource driver
currently provided is the jiffies clocksource, this should result in no
functional change. Additionally, a timekeeping_init and timekeeping_resume
function has been added to initialize and maintain some of the new timekeping
state.
[hirofumi@mail.parknet.co.jp: fixlet]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This introduces the clocksource management infrastructure. A clocksource is a
driver-like architecture generic abstraction of a free-running counter. This
code defines the clocksource structure, and provides management code for
registering, selecting, accessing and scaling clocksources.
Additionally, this includes the trivial jiffies clocksource, a lowest common
denominator clocksource, provided mainly for use as an example.
[hirofumi@mail.parknet.co.jp: Don't enable IRQ too early]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds "-o bh" option to force use of buffer_heads. This option
is needed when we make "nobh" as default - and if we run into problems.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Eric W. Biederman