Commit 238305bb4d ("mm: remove sparsemem allocation details from the
bootmem allocator") introduced a bug in the allocation goal calculation
that put section usemaps not in the same section as the node
descriptors, creating unnecessary hotplug dependencies between them:
node 0 must be removed before remove section 16399
node 1 must be removed before remove section 16399
node 2 must be removed before remove section 16399
node 3 must be removed before remove section 16399
node 4 must be removed before remove section 16399
node 5 must be removed before remove section 16399
node 6 must be removed before remove section 16399
The reason is that it applies PAGE_SECTION_MASK to the physical address
of the node descriptor when finding a suitable place to put the usemap,
when this mask is actually intended to be used with PFNs. Because the
PFN mask is wider, the target address will point beyond the wanted
section holding the node descriptor and the node must be offlined before
the section holding the usemap can go.
Fix this by extending the mask to address width before use.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
shmem_add_to_page_cache() has three callsites, but only one of them wants
the radix_tree_preload() (an exceptional entry guarantees that the radix
tree node is present in the other cases), and only that site can achieve
mem_cgroup_uncharge_cache_page() (PageSwapCache makes it a no-op in the
other cases). We did it this way originally to reflect
add_to_page_cache_locked(); but it's confusing now, so move the radix_tree
preloading and mem_cgroup uncharging to that one caller.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When adding the page_private checks before calling shmem_replace_page(), I
did realize that there is a further race, but thought it too unlikely to
need a hurried fix.
But independently I've been chasing why a mem cgroup's memory.stat
sometimes shows negative rss after all tasks have gone: I expected it to
be a stats gathering bug, but actually it's shmem swapping's fault.
It's an old surprise, that when you lock_page(lookup_swap_cache(swap)),
the page may have been removed from swapcache before getting the lock; or
it may have been freed and reused and be back in swapcache; and it can
even be using the same swap location as before (page_private same).
The swapoff case is already secure against this (swap cannot be reused
until the whole area has been swapped off, and a new swapped on); and
shmem_getpage_gfp() is protected by shmem_add_to_page_cache()'s check for
the expected radix_tree entry - but a little too late.
By that time, we might have already decided to shmem_replace_page(): I
don't know of a problem from that, but I'd feel more at ease not to do so
spuriously. And we have already done mem_cgroup_cache_charge(), on
perhaps the wrong mem cgroup: and this charge is not then undone on the
error path, because PageSwapCache ends up preventing that.
It's this last case which causes the occasional negative rss in
memory.stat: the page is charged here as cache, but (sometimes) found to
be anon when eventually it's uncharged - and in between, it's an
undeserved charge on the wrong memcg.
Fix this by adding an earlier check on the radix_tree entry: it's
inelegant to descend the tree twice, but swapping is not the fast path,
and a better solution would need a pair (try+commit) of memcg calls, and a
rework of shmem_replace_page() to keep out of the swapcache.
We can use the added shmem_confirm_swap() function to replace the
find_get_page+page_cache_release we were already doing on the error path.
And add a comment on that -EEXIST: it seems a peculiar errno to be using,
but originates from its use in radix_tree_insert().
[It can be surprising to see positive rss left in a memcg's memory.stat
after all tasks have gone, since it is supposed to count anonymous but not
shmem. Aside from sharing anon pages via fork with a task in some other
memcg, it often happens after swapping: because a swap page can't be freed
while under writeback, nor while locked. So it's not an error, and these
residual pages are easily freed once pressure demands.]
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert 4fb5ef089b ("tmpfs: support SEEK_DATA and SEEK_HOLE"). I believe
it's correct, and it's been nice to have from rc1 to rc6; but as the
original commit said:
I don't know who actually uses SEEK_DATA or SEEK_HOLE, and whether it
would be of any use to them on tmpfs. This code adds 92 lines and 752
bytes on x86_64 - is that bloat or worthwhile?
Nobody asked for it, so I conclude that it's bloat: let's revert tmpfs to
the dumb generic support for v3.5. We can always reinstate it later if
useful, and anyone needing it in a hurry can just get it out of git.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Josef Bacik <josef@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andreas Dilger <adilger@dilger.ca>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Marco Stornelli <marco.stornelli@gmail.com>
Cc: Jeff liu <jeff.liu@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Requesting a threaded interrupt without a primary handler and without
IRQF_ONESHOT is dangerous, and after commit 1c6c6952 ("genirq: Reject
bogus threaded irq requests"), these requests are rejected. This causes
->probe() to fail, and the RTC driver not to be availble.
To fix, add IRQF_ONESHOT to the IRQ flags.
Tested on OMAP3730/OveroSTORM and OMAP4430/Panda board using rtcwake to
wake from system suspend multiple times.
Signed-off-by: Kevin Hilman <khilman@ti.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fat_encode_fh() can fetch an invalid i_pos value on systems where 64-bit
accesses are not atomic. Make it use the same accessor as the rest of the
FAT code.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the OMAP CPUFreq driver to the list of files in the OMAP Power
Management section.
I've already been maintaining this driver, this just makes it official.
Signed-off-by: Kevin Hilman <khilman@ti.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The code here has a nested spin_lock_irqsave(). It's not needed since
IRQs are already disabled and it causes a problem because it means that
IRQs won't be enabled again at the end. The second call to
spin_lock_irqsave() will overwrite the value of irq_flags and we can't
restore the proper settings.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Robin Holt <holt@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a bug in the below scenario for !CONFIG_MMU:
1. create a new file
2. mmap the file and write to it
3. read the file can't get the correct value
Because
sys_read() -> generic_file_aio_read() -> simple_readpage() -> clear_page()
which causes the page to be zeroed.
Add SetPageUptodate() to ramfs_nommu_expand_for_mapping() so that
generic_file_aio_read() do not call simple_readpage().
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should goto error to release memory resource if hotadd_new_pgdat()
failed.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki ISIMATU <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Len Brown <lenb@kernel.org>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the build error:
include/linux/regset.h: In function 'user_regset_copyout_zero':
include/linux/regset.h:289:3: error: implicit declaration of function '__clear_user' [-Werror=implicit-function-declaration]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__gu_val is const if the passed ptr is const, giving:
include/linux/pagemap.h: In function 'fault_in_pages_readable':
include/linux/pagemap.h:442:2: error: assignment of read-only variable '__gu_val'
include/linux/pagemap.h:448:4: error: assignment of read-only variable '__gu_val'
include/linux/pagemap.h: In function 'fault_in_multipages_readable':
include/linux/pagemap.h:499:3: error: assignment of read-only variable '__gu_val'
include/linux/pagemap.h:508:3: error: assignment of read-only variable '__gu_val'
make[4]: *** [init/main.o] Error 1
As we don't care about the actual value of __gu_val in the unhandled
case (it will cause a link error anyway), just remove the assignment.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the build error:
arch/h8300/kernel/time.c: In function 'h8300_timer_tick':
arch/h8300/kernel/time.c:39:2: error: implicit declaration of function 'get_irq_regs' [-Werror=implicit-function-declaration]
arch/h8300/kernel/time.c:39:42: error: invalid type argument of '->' (have 'int')
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The keyword is "static", not "statis":
arch/h8300/kernel/signal.c:455:8: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'void'
arch/h8300/kernel/signal.c: In function 'do_notify_resume':
arch/h8300/kernel/signal.c:511:3: error: implicit declaration of function 'do_signal' [-Werror=implicit-function-declaration]
arch/h8300/kernel/signal.c: At top level:
arch/h8300/kernel/signal.c:414:1: warning: 'handle_signal' defined but not used [-Wunused-function]
Introduced in commit 7ae4e32a65 ("h8300: switch to saved_sigmask-based
sigsuspend/rt_sigsuspend")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the h8300 build error:
kernel/sched/core.c: In function 'context_switch':
kernel/sched/core.c:2061:2: error: implicit declaration of function 'arch_start_context_switch' [-Werror=implicit-function-declaration]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Without this patch, if Device Tree is enabled the AB8500 RTC wouldn't get
probed at all, as there is no reference to it from platform code. This
patch ensures the driver is probed during normal DT start-up.
[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This driver's IRQ registration is failing because the kernel now forces
IRQs to be ONESHOT if no IRQ handler is passed.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If page migration cannot charge the temporary page to the memcg,
migrate_pages() will return -ENOMEM. This isn't considered in memory
compaction however, and the loop continues to iterate over all
pageblocks trying to isolate and migrate pages. If a small number of
very large memcgs happen to be oom, however, these attempts will mostly
be futile leading to an enormous amout of cpu consumption due to the
page migration failures.
This patch will short circuit and fail memory compaction if
migrate_pages() returns -ENOMEM. COMPACT_PARTIAL is returned in case
some migrations were successful so that the page allocator will retry.
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
"no other files mapped" requirement from my previous patch (c/r: prctl:
update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removal) is too
paranoid, it forbids operation even if there mapped one shared-anon vma.
Let's check that current mm->exe_file already unmapped, in this case
exe_file symlink already outdated and its changing is reasonable.
Plus, this patch fixes exit code in case operation success.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Reported-by: Cyrill Gorcunov <gorcunov@openvz.org>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As ocfs2_fallocate() will invoke __ocfs2_change_file_space() with a NULL
as the first parameter (file), it may trigger a NULL pointer dereferrence
due to a missing check.
Addresses http://bugs.launchpad.net/bugs/1006012
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Reported-by: Bret Towe <magnade@gmail.com>
Tested-by: Bret Towe <magnade@gmail.com>
Cc: Sunil Mushran <sunil.mushran@oracle.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Acked-by: Mark Fasheh <mfasheh@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the warnings:
arch/mn10300/kernel/irq.c:173:7: warning: "CONFIG_MN10300_TTYSM1_TIMER9" is not defined [-Wundef]
arch/mn10300/kernel/irq.c:175:7: warning: "CONFIG_MN10300_TTYSM1_TIMER3" is not defined [-Wundef]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the warnings:
arch/mn10300/mm/dma-alloc.c: At top level:
arch/mn10300/mm/dma-alloc.c:63:1: warning: data definition has no type or storage class [enabled by default]
arch/mn10300/mm/dma-alloc.c:63:1: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL' [-Wimplicit-int]
arch/mn10300/mm/dma-alloc.c:63:1: warning: parameter names (without types) in function declaration [enabled by default]
arch/mn10300/mm/dma-alloc.c:75:1: warning: data definition has no type or storage class [enabled by default]
arch/mn10300/mm/dma-alloc.c:75:1: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL' [-Wimplicit-int]
arch/mn10300/mm/dma-alloc.c:75:1: warning: parameter names (without types) in function declaration [enabled by default]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the warning:
arch/mn10300/kernel/traps.c:304:1: warning: data definition has no type or storage class [enabled by default]
arch/mn10300/kernel/traps.c:304:1: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL' [-Wimplicit-int]
arch/mn10300/kernel/traps.c:304:1: warning: parameter names (without types) in function declaration [enabled by default]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the nm10300 build failure:
In file included from arch/mn10300/kernel/csrc-mn10300.c:14:0:
arch/mn10300/kernel/internal.h:42:1: error: unknown type name 'irqreturn_t'
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the warning:
include/linux/ptrace.h:66:0: warning: "PTRACE_O_TRACESYSGOOD" redefined [enabled by default]
arch/mn10300/include/asm/ptrace.h:85:0: note: this is the location of the previous definition
We already have it in <linux/ptrace.h>, so remove it from <asm/ptrace.h>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the static inline function setup_jiffies_interrupt() from
<asm/timex.h> to arch/mn10300/kernel/cevt-mn10300.c, which is its only
callsite.
This allows to remove the inclusion of <asm/hardirq.h> and <linux/irq.h>
from <asm/timex.h> and <unit/timex.h>, fixing include hell like:
include/linux/jiffies.h:260:31: warning: "CLOCK_TICK_RATE" is not defined [-Wundef]
include/linux/jiffies.h:260:31: warning: "CLOCK_TICK_RATE" is not defined [-Wundef]
include/linux/jiffies.h:46:42: error: division by zero in #if
...
make[4]: *** [arch/mn10300/kernel/asm-offsets.s] Error 1
and (after a quick hack for the above by defining CLOCK_TICK_RATE in
<linux/jiffies.h>):
In file included from include/linux/notifier.h:15:0,
from include/linux/memory_hotplug.h:6,
from include/linux/mmzone.h:718,
from include/linux/gfp.h:4,
from include/linux/irq.h:20,
from arch/mn10300/unit-asb2303/include/unit/timex.h:15,
from arch/mn10300/include/asm/timex.h:15,
from include/linux/timex.h:174,
from include/linux/jiffies.h:8,
from include/linux/ktime.h:25,
from include/linux/timer.h:5,
from include/linux/workqueue.h:8,
include/linux/srcu.h:55:22: error: field 'work' has incomplete type
As a consequence, we do need a few more inclusions of <asm/irq.h>, namely
in arch/mn10300/unit-asb2303/smc91111.c and
arch/mn10300/unit-asb2305/unit-init.c.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
`config' is freed and is then used in the rtc_device_unregister() call,
causing a kernel panic.
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Reviewed-by: Viresh Kumar <viresh.linux@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
_pci_assign_resource() took an int "size" argument, which meant that
sizes larger than 4GB were truncated. Change type to resource_size_t.
[bhelgaas: changelog]
Signed-off-by: Nikhil P Rao <nikhil.rao@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This converts the U300 clock implementation over to use the common
struct clk and moves the implementation down into drivers/clk.
Since VCO isn't used in tree it was removed, it's not hard to
put it back in if need be.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[mturquette@linaro.org: trivial Makefile conflict]
Signed-off-by: Mike Turquette <mturquette@linaro.org>
caching parent clocks makes sense only when a clock has more
than one parent (mux clocks).
Avoid doing this for every other clock.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
[mturquette@linaro.org: removed extra parentheses]
Signed-off-by: Mike Turquette <mturquette@linaro.org>
The WM831x and WM832x series of PMICs contain a flexible clocking
subsystem intended to provide always on and system core clocks. It
features:
- A 32.768kHz crystal oscillator which can optionally be used to pass
through an externally generated clock.
- A FLL which can be clocked from either the 32.768kHz oscillator or
the CLKIN pin.
- A CLKOUT pin which can bring out either the oscillator or the FLL
output.
- The 32.768kHz clock can also optionally be brought out on the GPIO
pins of the device.
This driver fully supports the 32.768kHz oscillator and CLKOUT. The FLL
is supported only in AUTO mode, the full flexibility of the FLL cannot
currently be used.
Due to a lack of access to systems where the core SoC has been converted
to use the generic clock API this driver has been compile tested only.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Allow drivers to declare their clk_init_data const, the framework really
shouldn't be modifying the data.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Most platforms end up using a mix of basic clock types and
some which use clk_hw_foo struct for filling in custom platform
information when the clocks don't fit into basic types supported.
In platform code, its useful to know if a clock is using a basic
type or clk_hw_foo, which helps platforms know if they can
safely use to_clk_hw_foo to derive the clk_hw_foo pointer from
clk_hw.
Mark all basic clocks with a CLK_IS_BASIC flag.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Some divider clks do not have any obvious relationship
between the divider and the value programmed in the
register. For instance, say a value of 1 could signify divide
by 6 and a value of 2 could signify divide by 4 etc.
Also there are dividers where not all values possible
based on the bitfield width are valid. For instance
a 3 bit wide bitfield can be used to program a value
from 0 to 7. However its possible that only 0 to 4
are valid values.
All these cases need the platform code to pass a simple
table of divider/value tuple, so the framework knows
the exact value to be written based on the divider
calculation and can also do better error checking.
This patch adds support for such rate table based
dividers and as part of the support adds a new
registration function 'clk_register_divider_table()'
and a new macro for static definition
'DEFINE_CLK_DIVIDER_TABLE'.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Quite often dividers and the value programmed in the
register have a relation of 'power of two', something like
value div
0 1
1 2
2 4
3 8...
Add support for such dividers as part of clk-divider.
The clk-divider flag 'CLK_DIVIDER_POWER_OF_TWO' should be used
to define such clocks.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
The update of the hrtimer base offsets on all cpus cannot be made
atomically from the timekeeper.lock held and interrupt disabled region
as smp function calls are not allowed there.
clock_was_set(), which enforces the update on all cpus, is called
either from preemptible process context in case of do_settimeofday()
or from the softirq context when the offset modification happened in
the timer interrupt itself due to a leap second.
In both cases there is a race window for an hrtimer interrupt between
dropping timekeeper lock, enabling interrupts and clock_was_set()
issuing the updates. Any interrupt which arrives in that window will
see the new time but operate on stale offsets.
So we need to make sure that an hrtimer interrupt always sees a
consistent state of time and offsets.
ktime_get_update_offsets() allows us to get the current monotonic time
and update the per cpu hrtimer base offsets from hrtimer_interrupt()
to capture a consistent state of monotonic time and the offsets. The
function replaces the existing ktime_get() calls in hrtimer_interrupt().
The overhead of the new function vs. ktime_get() is minimal as it just
adds two store operations.
This ensures that any changes to realtime or boottime offsets are
noticed and stored into the per-cpu hrtimer base structures, prior to
any hrtimer expiration and guarantees that timers are not expired early.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1341960205-56738-8-git-send-email-johnstul@us.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
To finally fix the infamous leap second issue and other race windows
caused by functions which change the offsets between the various time
bases (CLOCK_MONOTONIC, CLOCK_REALTIME and CLOCK_BOOTTIME) we need a
function which atomically gets the current monotonic time and updates
the offsets of CLOCK_REALTIME and CLOCK_BOOTTIME with minimalistic
overhead. The previous patch which provides ktime_t offsets allows us
to make this function almost as cheap as ktime_get() which is going to
be replaced in hrtimer_interrupt().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Link: http://lkml.kernel.org/r/1341960205-56738-7-git-send-email-johnstul@us.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We need to update the base offsets from this code and we need to do
that under base->lock. Move the lock held region around the
ktime_get() calls. The ktime_get() calls are going to be replaced with
a function which gets the time and the offsets atomically.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Link: http://lkml.kernel.org/r/1341960205-56738-6-git-send-email-johnstul@us.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We need to update the hrtimer clock offsets from the hrtimer interrupt
context. To avoid conversions from timespec to ktime_t maintain a
ktime_t based representation of those offsets in the timekeeper. This
puts the conversion overhead into the code which updates the
underlying offsets and provides fast accessible values in the hrtimer
interrupt.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1341960205-56738-4-git-send-email-johnstul@us.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The timekeeping code misses an update of the hrtimer subsystem after a
leap second happened. Due to that timers based on CLOCK_REALTIME are
either expiring a second early or late depending on whether a leap
second has been inserted or deleted until an operation is initiated
which causes that update. Unless the update happens by some other
means this discrepancy between the timekeeping and the hrtimer data
stays forever and timers are expired either early or late.
The reported immediate workaround - $ data -s "`date`" - is causing a
call to clock_was_set() which updates the hrtimer data structures.
See: http://www.sheeri.com/content/mysql-and-leap-second-high-cpu-and-fix
Add the missing clock_was_set() call to update_wall_time() in case of
a leap second event. The actual update is deferred to softirq context
as the necessary smp function call cannot be invoked from hard
interrupt context.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Reported-by: Jan Engelhardt <jengelh@inai.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1341960205-56738-3-git-send-email-johnstul@us.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
clock_was_set() cannot be called from hard interrupt context because
it calls on_each_cpu().
For fixing the widely reported leap seconds issue it is necessary to
call it from hard interrupt context, i.e. the timer tick code, which
does the timekeeping updates.
Provide a new function which denotes it in the hrtimer cpu base
structure of the cpu on which it is called and raise the hrtimer
softirq. We then execute the clock_was_set() notificiation from
softirq context in run_hrtimer_softirq(). The hrtimer softirq is
rarely used, so polling the flag there is not a performance issue.
[ tglx: Made it depend on CONFIG_HIGH_RES_TIMERS. We really should get
rid of all this ifdeffery ASAP ]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Reported-by: Jan Engelhardt <jengelh@inai.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1341960205-56738-2-git-send-email-johnstul@us.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
