if get_rtc_time() is _ever_ called with IRQs off, we deadlock badly
in it, waiting for jiffies to increment.
So make the code more robust by doing an explicit mdelay(20).
This solves a very hard to reproduce/debug hard lockup reported
by Mikael Pettersson.
Reported-by: Mikael Pettersson <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
improve the debug printout:
- make it actually display something
- print it only once
would be nice to have a WARN_ONCE() facility, to feed such things to
kerneloops.org.
Signed-off-by: Ingo Molnar <[email protected]>
as per this discussion:
http://lkml.org/lkml/2008/8/12/423
Pardo reported that 64-bit threaded apps, if their stacks exceed the
combined size of ~4GB, slow down drastically in pthread_create() - because
glibc uses MAP_32BIT to allocate the stacks. The use of MAP_32BIT is
a legacy hack - to speed up context switching on certain early model
64-bit P4 CPUs.
So introduce a new flag to be used by glibc instead, to not constrain
64-bit apps like this.
glibc can switch to this new flag straight away - it will be ignored
by the kernel. If those old CPUs ever matter to anyone, support for
it can be implemented.
Signed-off-by: Ingo Molnar <[email protected]>
Acked-by: Ulrich Drepper <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
as per this discussion:
http://lkml.org/lkml/2008/8/12/423
Pardo reported that 64-bit threaded apps, if their stacks exceed the
combined size of ~4GB, slow down drastically in pthread_create() - because
glibc uses MAP_32BIT to allocate the stacks. The use of MAP_32BIT is
a legacy hack - to speed up context switching on certain early model
64-bit P4 CPUs.
So introduce a new flag to be used by glibc instead, to not constrain
64-bit apps like this.
glibc can switch to this new flag straight away - it will be ignored
by the kernel. If those old CPUs ever matter to anyone, support for
it can be implemented.
Signed-off-by: Ingo Molnar <[email protected]>
Acked-by: Ulrich Drepper <[email protected]>
fix:
kernel/built-in.o: In function `lockdep_stats_show':
lockdep_proc.c:(.text+0x3cb2f): undefined reference to `lockdep_count_forward_deps'
kernel/built-in.o: In function `l_show':
lockdep_proc.c:(.text+0x3d02b): undefined reference to `lockdep_count_forward_deps'
lockdep_proc.c:(.text+0x3d047): undefined reference to `lockdep_count_backward_deps'
Signed-off-by: Ingo Molnar <[email protected]>
certain configs produce:
[ 70.076229] BUG: MAX_LOCKDEP_KEYS too low!
[ 70.080230] turning off the locking correctness validator.
tune them up.
Signed-off-by: Ingo Molnar <[email protected]>
the names were too generic:
drivers/uio/uio.c:87: error: expected identifier or '(' before 'do'
drivers/uio/uio.c:87: error: expected identifier or '(' before 'while'
drivers/uio/uio.c:113: error: 'map_release' undeclared here (not in a function)
Signed-off-by: Ingo Molnar <[email protected]>
fix:
net/ipv4/route.c: In function 'ip_static_sysctl_init':
net/ipv4/route.c:3225: error: 'ipv4_route_path' undeclared (first use in this function)
net/ipv4/route.c:3225: error: (Each undeclared identifier is reported only once
net/ipv4/route.c:3225: error: for each function it appears in.)
net/ipv4/route.c:3225: error: 'ipv4_route_table' undeclared (first use in this function)
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
When taking the time of a remote CPU, use the opportunity to
couple (sync) the clocks to each other. (in a monotonic way)
Signed-off-by: Ingo Molnar <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Acked-by: Mike Galbraith <[email protected]>
- return the current clock instead of letting callers
fetch it from scd->clock
Signed-off-by: Ingo Molnar <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Acked-by: Mike Galbraith <[email protected]>
eliminate prev_raw and use tick_raw instead.
It's enough to base the current time on the scheduler tick timestamp
alone - the monotonicity and maximum checks will prevent any damage.
Signed-off-by: Ingo Molnar <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Acked-by: Mike Galbraith <[email protected]>
Found an interactivity problem on a quad core test-system - simple
CPU loops would occasionally delay the system un an unacceptable way.
After much debugging with Peter Zijlstra it turned out that the problem
is caused by the string of sched_clock() changes - they caused the CPU
clock to jump backwards a bit - which confuses the scheduler arithmetics.
(which is unsigned for performance reasons)
So revert:
# c300ba2: sched_clock: and multiplier for TSC to gtod drift
# c0c8773: sched_clock: only update deltas with local reads.
# af52a90: sched_clock: stop maximum check on NO HZ
# f7cce27: sched_clock: widen the max and min time
This solves the interactivity problems.
Signed-off-by: Ingo Molnar <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Acked-by: Mike Galbraith <[email protected]>
fix build bug introduced by 95b68dec0d "calgary iommu: use the first
kernels TCE tables in kdump":
arch/x86/kernel/built-in.o: In function `calgary_iommu_init':
(.init.text+0x8399): undefined reference to `elfcorehdr_addr'
arch/x86/kernel/built-in.o: In function `calgary_iommu_init':
(.init.text+0x856c): undefined reference to `elfcorehdr_addr'
arch/x86/kernel/built-in.o: In function `detect_calgary':
(.init.text+0x8c68): undefined reference to `elfcorehdr_addr'
arch/x86/kernel/built-in.o: In function `detect_calgary':
(.init.text+0x8d0c): undefined reference to `elfcorehdr_addr'
make elfcorehdr_addr a generally available symbol.
Signed-off-by: Ingo Molnar <[email protected]>
on !CONFIG_SYSCTL on x86 with latest -git i get:
mm/hugetlb.c: In function 'decrement_hugepage_resv_vma':
mm/hugetlb.c:83: error: 'reserve' undeclared (first use in this function)
mm/hugetlb.c:83: error: (Each undeclared identifier is reported only once
mm/hugetlb.c:83: error: for each function it appears in.)
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
remove the :vim=ft=help tag from trace files.
I used them years ago to syntax-highlight traces and forgot about this hack.
Signed-off-by: Ingo Molnar <[email protected]>
Evgeniy Polyakov noticed that drivers/net/e1000e/netdev.c:e1000_netpoll()
was calling e1000_clean_tx_irq() without taking the TX lock.
David Miller suggested to remove the call altogether: since in this
callpah there's periodic calls to ->poll() anyway which will do
e1000_clean_tx_irq() and will garbage-collect any finished TX ring
descriptors.
This fix solved the e1000e+netconsole crashes i've been seeing:
=============================================================================
BUG skbuff_head_cache: Poison overwritten
-----------------------------------------------------------------------------
INFO: 0xf658ae9c-0xf658ae9c. First byte 0x6a instead of 0x6b
INFO: Allocated in __alloc_skb+0x2c/0x110 age=0 cpu=0 pid=5098
INFO: Freed in __kfree_skb+0x31/0x80 age=0 cpu=1 pid=4440
INFO: Slab 0xc16cc140 objects=16 used=1 fp=0xf658ae00 flags=0x400000c3
INFO: Object 0xf658ae00 @offset=3584 fp=0xf658af00
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Andrew Morton reported this s390 allmodconfig build failure:
kernel/built-in.o: In function `hrtick_start_fair':
sched.c:(.text+0x69c6): undefined reference to `__smp_call_function_single'
the reason is that s390 is not a generic-ipi SMP platform yet, while
the hrtick code relies on it. Fix the dependency.
Signed-off-by: Ingo Molnar <[email protected]>
various drivers were using the wrong APIs:
drivers/built-in.o: In function `hp_probe1':
hp.c:(.init.text+0xa280): undefined reference to `NS8390_init'
fixed via:
cd drivers/net/; sed -i 's/NS8390_/NS8390p_/g' \
$(grep -l NS8390_ $(grep 8390p.o Makefile | cut -d' ' -f3 | \
sed 's/.o$/.c/g'))
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Jeff Garzik <[email protected]>
-tip testing found this build bug:
arch/x86/kvm/built-in.o:(.text.fixup+0x1): relocation truncated to fit: R_X86_64_32 against `.text'
arch/x86/kvm/built-in.o:(.text.fixup+0xb): relocation truncated to fit: R_X86_64_32 against `.text'
arch/x86/kvm/built-in.o:(.text.fixup+0x15): relocation truncated to fit: R_X86_64_32 against `.text'
arch/x86/kvm/built-in.o:(.text.fixup+0x1f): relocation truncated to fit: R_X86_64_32 against `.text'
arch/x86/kvm/built-in.o:(.text.fixup+0x29): relocation truncated to fit: R_X86_64_32 against `.text'
Introduced by commit 4ecac3fd. The problem is that 'push' will default
to 32-bit, which is not wide enough as a fixup address. (and which would
crash on any real fixup event even if it was wide enough)
Introduce KVM_EX_PUSH to get the proper address push width on 64-bit too.
Signed-off-by: Ingo Molnar <[email protected]>
From: Arjan van de Ven <[email protected]>
Date: Sat, 19 Jul 2008 15:47:17 -0700
CONFIG_NONPROMISC_DEVMEM was a rather confusing name - but renaming it
to CONFIG_PROMISC_DEVMEM causes problems on architectures that do not
support this feature; this patch renames it to CONFIG_STRICT_DEVMEM,
so that architectures can opt-in into it.
( the polarity of the option is still the same as it was originally; it
needs to be for now to not break architectures that don't have the
infastructure yet to support this feature)
Signed-off-by: Arjan van de Ven <[email protected]>
Cc: "V.Radhakrishnan" <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
re-enable OPTIMIZE_INLINING more widely. Jeff Dike fixed the remaining
outstanding issue in this commit:
| commit 4f81c5350b
| Author: Jeff Dike <[email protected]>
| Date: Mon Jul 7 13:36:56 2008 -0400
|
| [UML] fix gcc ICEs and unresolved externs
[...]
| This patch reintroduces unit-at-a-time for gcc >= 4.0, bringing back the
| possibility of Uli's crash. If that happens, we'll debug it.
it's still default-off and thus opt-in.
Signed-off-by: Ingo Molnar <[email protected]>
provide an empty partition_sched_domains() definition for the UP case:
include/linux/cpuset.h: In function ‘rebuild_sched_domains':
include/linux/cpuset.h:163: error: implicit declaration of function ‘partition_sched_domains'
Signed-off-by: Ingo Molnar <[email protected]>
Yinghai Lu noticed that arch/x86/kernel/smpcommon_32.c got
renamed to arch/x86/kernel/smpcommon.c but the old almost-empty
file stayed around. Zap it.
Reported-by: Yinghai Lu <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Linus observed:
> The real bug is that we shouldn't have "double negatives", and
> certainly not negative config options. Making that "promiscuous
> /dev/mem" option a negated thing as a config option was bad.
right ... lets rename this option. There should never be a negation
in config options.
[ that reminds me of CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER, but that
is for another commit ;-) ]
Signed-off-by: Ingo Molnar <[email protected]>
make function tracing more robust: do not trace library functions.
We've already got a sizable list of exceptions:
ifdef CONFIG_FTRACE
# Do not profile string.o, since it may be used in early boot or vdso
CFLAGS_REMOVE_string.o = -pg
# Also do not profile any debug utilities
CFLAGS_REMOVE_spinlock_debug.o = -pg
CFLAGS_REMOVE_list_debug.o = -pg
CFLAGS_REMOVE_debugobjects.o = -pg
CFLAGS_REMOVE_find_next_bit.o = -pg
CFLAGS_REMOVE_cpumask.o = -pg
CFLAGS_REMOVE_bitmap.o = -pg
endif
... and the pattern has been that random library functionality showed
up in ftrace's critical path (outside of its recursion check), causing
hard to debug lockups.
So be a bit defensive about it and exclude all lib/*.o functions by
default. It's not that they are overly interesting for tracing purposes
anyway. Specific ones can still be traced, in an opt-in manner.
Signed-off-by: Ingo Molnar <[email protected]>
MAXSMP brings in lots of use of various bitops in smp_processor_id()
and friends - causing ftrace to lock up during bootup:
calling anon_inode_init+0x0/0x130
initcall anon_inode_init+0x0/0x130 returned 0 after 0 msecs
calling acpi_event_init+0x0/0x57
[ hard hang ]
So exclude the bitops facilities from tracing.
Signed-off-by: Ingo Molnar <[email protected]>
-tip testing found a bootup hang here:
initcall anon_inode_init+0x0/0x130 returned 0 after 0 msecs
calling acpi_event_init+0x0/0x57
the bootup should have continued with:
initcall acpi_event_init+0x0/0x57 returned 0 after 45 msecs
but it hung hard there instead.
bisection led to this commit:
| commit 5806b81ac1
| Merge: d14c8a6... 6712e29...
| Author: Ingo Molnar <[email protected]>
| Date: Mon Jul 14 16:11:52 2008 +0200
| Merge branch 'auto-ftrace-next' into tracing/for-linus
turns out that i made this mistake in the merge:
ifdef CONFIG_FTRACE
# Do not profile debug utilities
CFLAGS_REMOVE_tsc_64.o = -pg
CFLAGS_REMOVE_tsc_32.o = -pg
those two files got unified meanwhile - so the dont-profile annotation
got lost. The proper rule is:
CFLAGS_REMOVE_tsc.o = -pg
i guess this could have been caught sooner if the CFLAGS_REMOVE* kbuild
rule aborted the build if it met a target that does not exist anymore?
Signed-off-by: Ingo Molnar <[email protected]>
the paravirt-spinlock patches caused a boot hang with this config:
http://redhat.com/~mingo/misc/config-Wed_Jul__9_14_47_04_CEST_2008.bad
i have bisected it down to:
| commit e17b58c2e85bc2ad2afc07fb8d898017c2b75ed1
| Author: Jeremy Fitzhardinge <[email protected]>
| Date: Mon Jul 7 12:07:53 2008 -0700
|
| xen: implement Xen-specific spinlocks
i.e. applying that patch alone causes the hang. The hang happens in the
ftrace self-test:
initcall utsname_sysctl_init+0x0/0x19 returned 0 after 0 msecs
calling init_sched_switch_trace+0x0/0x4c
Testing tracer sched_switch: PASSED
initcall init_sched_switch_trace+0x0/0x4c returned 0 after 167 msecs
calling init_function_trace+0x0/0x12
Testing tracer ftrace:
[hard hang]
it should have continued like this:
Testing tracer ftrace: PASSED
initcall init_function_trace+0x0/0x12 returned 0 after 198 msecs
calling init_irqsoff_tracer+0x0/0x14
Testing tracer irqsoff: PASSED
initcall init_irqsoff_tracer+0x0/0x14 returned 0 after 3 msecs
calling init_mmio_trace+0x0/0x12
initcall init_mmio_trace+0x0/0x12 returned 0 after 0 msecs
the problem is that such lowlevel primitives as spinlocks should never
be built with -pg (which ftrace does). Marking paravirt.o as non-pg and
marking all spinlock ops as always-inline solve the hang.
Signed-off-by: Ingo Molnar <[email protected]>
fix:
arch/x86/xen/built-in.o: In function `xen_enable_syscall':
(.cpuinit.text+0xdb): undefined reference to `sysctl_vsyscall32'
Signed-off-by: Ingo Molnar <[email protected]>
This reverts commit 033786969d1d1b5af12a32a19d3a760314d05329.
Suresh Siddha reported that this broke booting on his 2GB testbox.
Reported-by: Suresh Siddha <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
This reverts commit 6fbbec428c8e7bb617da2e8a589af2e97bcf3bc4.
Rafael doesnt like it - it breaks various assumptions.
Signed-off-by: Ingo Molnar <[email protected]>
fix:
arch/x86/xen/enlighten.c: In function 'xen_set_fixmap':
arch/x86/xen/enlighten.c:1127: error: 'FIX_KMAP_BEGIN' undeclared (first use in this function)
arch/x86/xen/enlighten.c:1127: error: (Each undeclared identifier is reported only once
arch/x86/xen/enlighten.c:1127: error: for each function it appears in.)
arch/x86/xen/enlighten.c:1127: error: 'FIX_KMAP_END' undeclared (first use in this function)
make[1]: *** [arch/x86/xen/enlighten.o] Error 1
make: *** [arch/x86/xen/enlighten.o] Error 2
FIX_KMAP_BEGIN is only available on HIGHMEM.
Signed-off-by: Ingo Molnar <[email protected]>
fix:
arch/x86/xen/built-in.o: In function `set_page_prot':
enlighten.c:(.text+0x111d): undefined reference to `xen_raw_printk'
arch/x86/xen/built-in.o: In function `xen_start_kernel':
: undefined reference to `xen_raw_console_write'
arch/x86/xen/built-in.o: In function `xen_start_kernel':
: undefined reference to `xen_raw_console_write'
Signed-off-by: Ingo Molnar <[email protected]>
fix merge fallout:
arch/x86/pci/amd_bus.c: In function ‘enable_pci_io_ecs':
arch/x86/pci/amd_bus.c:581: error: too many arguments to function ‘on_each_cpu'
Signed-off-by: Ingo Molnar <[email protected]>
Ingo Molnar