13 Jan, 2012
3 commits
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Move CMPXCHG_DOUBLE and rename it to HAVE_CMPXCHG_DOUBLE so architectures
can simply select the option if it is supported.Signed-off-by: Heiko Carstens
Acked-by: Christoph Lameter
Cc: Pekka Enberg
Cc: Ingo Molnar
Cc: Thomas Gleixner
Cc: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Move CMPXCHG_LOCAL and rename it to HAVE_CMPXCHG_LOCAL so architectures
can simply select the option if it is supported.Signed-off-by: Heiko Carstens
Acked-by: Christoph Lameter
Cc: Pekka Enberg
Cc: Ingo Molnar
Cc: Thomas Gleixner
Cc: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
While implementing cmpxchg_double() on s390 I realized that we don't set
CONFIG_CMPXCHG_LOCAL despite the fact that we have support for it.However setting that option will increase the size of struct page by
eight bytes on 64 bit, which we certainly do not want. Also, it doesn't
make sense that a present cpu feature should increase the size of struct
page.Besides that it looks like the dependency to CMPXCHG_LOCAL is wrong and
that it should depend on CMPXCHG_DOUBLE instead.This patch:
If an architecture supports CMPXCHG_LOCAL this shouldn't result
automatically in larger struct pages if the SLUB allocator is used.
Instead introduce a new config option "HAVE_ALIGNED_STRUCT_PAGE" which
can be selected if a double word aligned struct page is required. Also
update x86 Kconfig so that it should work as before.Signed-off-by: Heiko Carstens
Acked-by: Christoph Lameter
Cc: Pekka Enberg
Cc: Ingo Molnar
Cc: Thomas Gleixner
Cc: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Nov, 2011
1 commit
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The legacy x86 nmi watchdog code was removed with the implementation
of the perf based nmi watchdog. This broke Oprofile's nmi timer
mode. To run nmi timer mode we relied on a continuous ticking nmi
source which the nmi watchdog provided. The nmi tick was no longer
available and current watchdog can not be used anymore since it runs
with very long periods in the range of seconds. This patch
reimplements the nmi timer mode using a perf counter nmi source.V2:
* removing pr_info()
* fix undefined reference to `__udivdi3' for 32 bit build
* fix section mismatch of .cpuinit.data:nmi_timer_cpu_nb
* removed nmi timer setup in arch/x86
* implemented function stubs for op_nmi_init/exit()
* made code more readable in oprofile_init()V3:
* fix architectural initialization in oprofile_init()
* fix CONFIG_OPROFILE_NMI_TIMER dependenciesAcked-by: Peter Zijlstra
Signed-off-by: Robert Richter
03 Aug, 2011
1 commit
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cmpxchg() is widely used by lockless code, including NMI-safe lockless
code. But on some architectures, the cmpxchg() implementation is not
NMI-safe, on these architectures the lockless code may need a
spin_trylock_irqsave() based implementation.This patch adds a Kconfig option: ARCH_HAVE_NMI_SAFE_CMPXCHG, so that
NMI-safe lockless code can depend on it or provide different
implementation according to it.On many architectures, cmpxchg is only NMI-safe for several specific
operand sizes. So, ARCH_HAVE_NMI_SAFE_CMPXCHG define in this patch
only guarantees cmpxchg is NMI-safe for sizeof(unsigned long).Signed-off-by: Huang Ying
Acked-by: Mike Frysinger
Acked-by: Paul Mundt
Acked-by: Hans-Christian Egtvedt
Acked-by: Benjamin Herrenschmidt
Acked-by: Chris Metcalf
Acked-by: Richard Henderson
CC: Mikael Starvik
Acked-by: David Howells
CC: Yoshinori Sato
CC: Tony Luck
CC: Hirokazu Takata
CC: Geert Uytterhoeven
CC: Michal Simek
Acked-by: Ralf Baechle
CC: Kyle McMartin
CC: Martin Schwidefsky
CC: Chen Liqin
CC: "David S. Miller"
CC: Ingo Molnar
CC: Chris Zankel
Signed-off-by: Len Brown
25 May, 2011
1 commit
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In case other architectures require RCU freed page-tables to implement
gup_fast() and software filled hashes and similar things, provide the
means to do so by moving the logic into generic code.Signed-off-by: Peter Zijlstra
Requested-by: David Miller
Cc: Benjamin Herrenschmidt
Cc: Martin Schwidefsky
Cc: Russell King
Cc: Paul Mundt
Cc: Jeff Dike
Cc: Richard Weinberger
Cc: Tony Luck
Cc: KAMEZAWA Hiroyuki
Cc: Hugh Dickins
Cc: Mel Gorman
Cc: KOSAKI Motohiro
Cc: Nick Piggin
Cc: Namhyung Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
10 Apr, 2011
1 commit
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Signed-off-by: Justin P. Mattock
Acked-by: Steven Rostedt
Acked-by: Heiko Carstens
Signed-off-by: Jiri Kosina
26 Nov, 2010
1 commit
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The spinning mutex implementation uses cpu_relax() in busy loops as a
compiler barrier. Depending on the architecture, cpu_relax() may do more
than needed in this specific mutex spin loops. On System z we also give
up the time slice of the virtual cpu in cpu_relax(), which prevents
effective spinning on the mutex.This patch replaces cpu_relax() in the spinning mutex code with
arch_mutex_cpu_relax(), which can be defined by each architecture that
selects HAVE_ARCH_MUTEX_CPU_RELAX. The default is still cpu_relax(), so
this patch should not affect other architectures than System z for now.Signed-off-by: Gerald Schaefer
Signed-off-by: Peter Zijlstra
LKML-Reference:
Signed-off-by: Ingo Molnar
30 Oct, 2010
1 commit
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On i386 (not x86_64) early implementations of gcc would have a bug
with asm goto causing it to produce code like the following:(This was noticed by Peter Zijlstra)
56 pushl 0
67 nopl jmp 0x6f
popl
jmp 0x8c6f mov
test
je 0x8c8c mov
call *(%esp)The jump added in the asm goto skipped over the popl that matched
the pushl 0, which lead up to a quick crash of the system when
the jump was enabled. The nopl is defined in the asm goto () statement
and when tracepoints are enabled, the nop changes to a jump to the label
that was specified by the asm goto. asm goto is suppose to tell gcc that
the code in the asm might jump to an external label. Here gcc obviously
fails to make that work.The bug report for gcc is here:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46226
The bug only appears on x86 when not compiled with
-maccumulate-outgoing-args. This option is always set on x86_64 and it
is also the work around for a function graph tracer i386 bug.
(See commit: 746357d6a526d6da9d89a2ec645b28406e959c2e)
This explains why the bug only showed up on i386 when function graph
tracer was not enabled.This patch now adds a CONFIG_JUMP_LABEL option that is default
off instead of using jump labels by default. When jump labels are
enabled, the -maccumulate-outgoing-args will be used (causing a
slightly larger kernel image on i386). This option will exist
until we have a way to detect if the gcc compiler in use is safe
to use on all configurations without the work around.Note, there exists such a test, but for now we will keep the enabling
of jump label as a manual option.Archs that know the compiler is safe with asm goto, may choose to
select JUMP_LABEL and enable it by default.Reported-by: Ingo Molnar
Cause-discovered-by: Peter Zijlstra
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Jason Baron
Cc: H. Peter Anvin
Cc: David Daney
Cc: Mathieu Desnoyers
Cc: Masami Hiramatsu
Cc: David Miller
Cc: Richard Henderson
LKML-Reference:
Signed-off-by: Steven Rostedt
24 Sep, 2010
1 commit
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…stedt/linux-2.6-trace into perf/core
23 Sep, 2010
1 commit
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base patch to implement 'jump labeling'. Based on a new 'asm goto' inline
assembly gcc mechanism, we can now branch to labels from an 'asm goto'
statment. This allows us to create a 'no-op' fastpath, which can subsequently
be patched with a jump to the slowpath code. This is useful for code which
might be rarely used, but which we'd like to be able to call, if needed.
Tracepoints are the current usecase that these are being implemented for.Acked-by: David S. Miller
Signed-off-by: Jason Baron
LKML-Reference:[ cleaned up some formating ]
Signed-off-by: Steven Rostedt
14 Sep, 2010
1 commit
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Fix Kconfig dependency among Kprobes, optprobe and kallsyms.
Kprobes uses kallsyms_lookup for finding target function and
checking instruction boundary, thus CONFIG_KPROBES should select
CONFIG_KALLSYMS.Optprobe is an optional feature which is supported on x86 arch,
and it also uses kallsyms_lookup for checking instructions in
the target function. Since KALLSYMS_ALL just adds symbols of
kernel variables, it doesn't need to select KALLSYMS_ALL.Signed-off-by: Masami Hiramatsu
Acked-by: Randy Dunlap ,
Cc: Ananth N Mavinakayanahalli
Cc: Felipe Contreras
Cc: Randy Dunlap
Cc: Ananth N Mavinakayanahalli
Cc: Anil S Keshavamurthy
Cc: David S. Miller
Cc: akpm
LKML-Reference:
Signed-off-by: Ingo Molnar
05 Aug, 2010
1 commit
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Conflicts:
kernel/MakefileMerge reason: Add the now complete topic, fix the conflict.
Signed-off-by: Ingo Molnar
16 May, 2010
2 commits
-
This new config is deemed to simplify even more the lockup detector
dependencies and can make it easier to bring a smooth sorting
between archs that support the new generic lockup detector and those
that still have their own, especially for those that are in the
middle of this migration.Instead of checking whether we have CONFIG_LOCKUP_DETECTOR +
CONFIG_PERF_EVENTS_NMI each time an arch wants to know if it needs
to build its own lockup detector, take a shortcut with this new
config. It is enabled only if the hardlockup detection part of
the whole lockup detector is on.Signed-off-by: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Peter Zijlstra
Cc: Don Zickus
Cc: Cyrill Gorcunov -
CONFIG_PERF_EVENT_NMI is something that need to be enabled from the
arch. This is fine on x86 as PERF_EVENTS is builtin but if other
archs select it, they will need to handle the PERF_EVENTS dependency.Instead, handle the dependency in the generic layer:
- archs need to tell what they support through HAVE_PERF_EVENTS_NMI
- Enable magically PERF_EVENTS_NMI if we have PERF_EVENTS and
HAVE_PERF_EVENTS_NMI.Signed-off-by: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Peter Zijlstra
Cc: Don Zickus
Cc: Cyrill Gorcunov
01 May, 2010
1 commit
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There are two outstanding fashions for archs to implement hardware
breakpoints.The first is to separate breakpoint address pattern definition
space between data and instruction breakpoints. We then have
typically distinct instruction address breakpoint registers
and data address breakpoint registers, delivered with
separate control registers for data and instruction breakpoints
as well. This is the case of PowerPc and ARM for example.The second consists in having merged breakpoint address space
definition between data and instruction breakpoint. Address
registers can host either instruction or data address and
the access mode for the breakpoint is defined in a control
register. This is the case of x86 and Super H.This patch adds a new CONFIG_HAVE_MIXED_BREAKPOINTS_REGS config
that archs can select if they belong to the second case. Those
will have their slot allocation merged for instructions and
data breakpoints.The others will have a separate slot tracking between data and
instruction breakpoints.Signed-off-by: Frederic Weisbecker
Acked-by: Paul Mundt
Cc: Will Deacon
Cc: Mahesh Salgaonkar
Cc: K. Prasad
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Ingo Molnar
16 Mar, 2010
1 commit
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Hide CONFIG_OPTPROBES and set if the arch supports optimized
kprobes (IOW, HAVE_OPTPROBES=y), since this option doesn't
change the major behavior of kprobes, and workarounds for minor
changes are documented.Signed-off-by: Masami Hiramatsu
Cc: systemtap
Cc: DLE
Cc: Dieter Ries
Cc: Ananth N Mavinakayanahalli
Cc: OGAWA Hirofumi
Cc: Peter Zijlstra
Cc: Mike Galbraith
Cc: Paul Mackerras
Cc: Arnaldo Carvalho de Melo
Cc: Frederic Weisbecker
LKML-Reference:
Signed-off-by: Ingo Molnar
06 Mar, 2010
1 commit
-
…nel/git/tip/linux-2.6-tip
* 'perf-probes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Issue at least one memory barrier in stop_machine_text_poke()
perf probe: Correct probe syntax on command line help
perf probe: Add lazy line matching support
perf probe: Show more lines after last line
perf probe: Check function address range strictly in line finder
perf probe: Use libdw callback routines
perf probe: Use elfutils-libdw for analyzing debuginfo
perf probe: Rename probe finder functions
perf probe: Fix bugs in line range finder
perf probe: Update perf probe document
perf probe: Do not show --line option without dwarf support
kprobes: Add documents of jump optimization
kprobes/x86: Support kprobes jump optimization on x86
x86: Add text_poke_smp for SMP cross modifying code
kprobes/x86: Cleanup save/restore registers
kprobes/x86: Boost probes when reentering
kprobes: Jump optimization sysctl interface
kprobes: Introduce kprobes jump optimization
kprobes: Introduce generic insn_slot framework
kprobes/x86: Cleanup RELATIVEJUMP_INSTRUCTION to RELATIVEJUMP_OPCODE
01 Mar, 2010
1 commit
-
…el/git/tip/linux-2.6-tip
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (28 commits)
ftrace: Add function names to dangling } in function graph tracer
tracing: Simplify memory recycle of trace_define_field
tracing: Remove unnecessary variable in print_graph_return
tracing: Fix typo of info text in trace_kprobe.c
tracing: Fix typo in prof_sysexit_enable()
tracing: Remove CONFIG_TRACE_POWER from kernel config
tracing: Fix ftrace_event_call alignment for use with gcc 4.5
ftrace: Remove memory barriers from NMI code when not needed
tracing/kprobes: Add short documentation for HAVE_REGS_AND_STACK_ACCESS_API
s390: Add pt_regs register and stack access API
tracing/kprobes: Make Kconfig dependencies generic
tracing: Unify arch_syscall_addr() implementations
tracing: Add notrace to TRACE_EVENT implementation functions
ftrace: Allow to remove a single function from function graph filter
tracing: Add correct/incorrect to sort keys for branch annotation output
tracing: Simplify test for function_graph tracing start point
tracing: Drop the tr check from the graph tracing path
tracing: Add stack dump to trace_printk if stacktrace option is set
tracing: Use appropriate perl constructs in recordmcount.pl
tracing: optimize recordmcount.pl for offsets-handling
...
26 Feb, 2010
4 commits
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OProfile support for IBS is now for several versions in the
kernel. The feature is stable now and the code can be activated
permanently.As a side effect IBS now works also on nosmp configs.
Signed-off-by: Robert Richter
-
OProfile is already used for a long time and no longer experimental.
Signed-off-by: Robert Richter
-
The commit
1155de4 ring-buffer: Make it generally available
already made ring-buffer available without the TRACING option
enabled. This patch removes the TRACING dependency from oprofile.Fixes also oprofile configuration on ia64.
The patch also applies to the 2.6.32-stable kernel.
Reported-by: Tony Jones
Cc: stable@kernel.org
Signed-off-by: Robert Richter -
Introduce kprobes jump optimization arch-independent parts.
Kprobes uses breakpoint instruction for interrupting execution
flow, on some architectures, it can be replaced by a jump
instruction and interruption emulation code. This gains kprobs'
performance drastically.To enable this feature, set CONFIG_OPTPROBES=y (default y if the
arch supports OPTPROBE).Changes in v9:
- Fix a bug to optimize probe when enabling.
- Check nearby probes can be optimize/unoptimize when disarming/arming
kprobes, instead of registering/unregistering. This will help
kprobe-tracer because most of probes on it are usually disabled.Changes in v6:
- Cleanup coding style for readability.
- Add comments around get/put_online_cpus().Changes in v5:
- Use get_online_cpus()/put_online_cpus() for avoiding text_mutex
deadlock.Signed-off-by: Masami Hiramatsu
Cc: systemtap
Cc: DLE
Cc: Ananth N Mavinakayanahalli
Cc: Jim Keniston
Cc: Srikar Dronamraju
Cc: Christoph Hellwig
Cc: Steven Rostedt
Cc: Frederic Weisbecker
Cc: Anders Kaseorg
Cc: Tim Abbott
Cc: Andi Kleen
Cc: Jason Baron
Cc: Mathieu Desnoyers
Cc: Frederic Weisbecker
Cc: Ananth N Mavinakayanahalli
LKML-Reference:
Signed-off-by: Ingo Molnar
23 Feb, 2010
1 commit
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So that arch developers know how to implement it without the
need to dig into changelogs.Reported-by: Mike Frysinger
Signed-off-by: Heiko Carstens
Acked-by: Masami Hiramatsu
Cc: Martin Schwidefsky
Cc: "David S . Miller"
Cc: Paul Mundt
Cc: Steven Rostedt
LKML-Reference:
[added reference to ptrace.h in the config help]
Signed-off-by: Frederic Weisbecker
17 Feb, 2010
1 commit
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KPROBES_EVENT actually depends on the regs and stack access API
(b1cf540f) and not on x86.
So introduce a new config option which architectures can select if
they have the API implemented and switch x86.Signed-off-by: Heiko Carstens
Acked-by: Masami Hiramatsu
Cc: Ingo Molnar
Cc: Martin Schwidefsky
LKML-Reference:
Signed-off-by: Frederic Weisbecker
18 Dec, 2009
1 commit
-
The kbuild's select command doesn't propagate through the config
dependencies.Hence the current rules of hardware breakpoint's config can't
ensure perf can never be disabled under us.We have:
config X86
selects HAVE_HW_BREAKPOINTSconfig HAVE_HW_BREAKPOINTS
select PERF_EVENTSconfig PERF_EVENTS
[...]x86 will select the breakpoints but that won't propagate to perf
events. The user can still disable the latter, but it is
necessary for the breakpoints.What we need is:
- x86 selects HAVE_HW_BREAKPOINTS and PERF_EVENTS
- HAVE_HW_BREAKPOINTS depends on PERF_EVENTSso that we ensure PERF_EVENTS is enabled and frozen for x86.
This fixes the following kind of build errors:
In file included from arch/x86/kernel/hw_breakpoint.c:31:
include/linux/hw_breakpoint.h: In function 'hw_breakpoint_addr':
include/linux/hw_breakpoint.h:39: error: 'struct perf_event' has no member named 'attr'v2: Select also ANON_INODES from x86, required for perf
Reported-by: Cyrill Gorcunov
Reported-by: Michal Marek
Reported-by: Andrew Randrianasulu
Signed-off-by: Frederic Weisbecker
Cc: Peter Zijlstra
Cc: Arnaldo Carvalho de Melo
Cc: Paul Mackerras
Cc: Randy Dunlap
Cc: K.Prasad
LKML-Reference:
Signed-off-by: Ingo Molnar
09 Dec, 2009
1 commit
-
* 'kvm-updates/2.6.33' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (84 commits)
KVM: VMX: Fix comparison of guest efer with stale host value
KVM: s390: Fix prefix register checking in arch/s390/kvm/sigp.c
KVM: Drop user return notifier when disabling virtualization on a cpu
KVM: VMX: Disable unrestricted guest when EPT disabled
KVM: x86 emulator: limit instructions to 15 bytes
KVM: s390: Make psw available on all exits, not just a subset
KVM: x86: Add KVM_GET/SET_VCPU_EVENTS
KVM: VMX: Report unexpected simultaneous exceptions as internal errors
KVM: Allow internal errors reported to userspace to carry extra data
KVM: Reorder IOCTLs in main kvm.h
KVM: x86: Polish exception injection via KVM_SET_GUEST_DEBUG
KVM: only clear irq_source_id if irqchip is present
KVM: x86: disallow KVM_{SET,GET}_LAPIC without allocated in-kernel lapic
KVM: x86: disallow multiple KVM_CREATE_IRQCHIP
KVM: VMX: Remove vmx->msr_offset_efer
KVM: MMU: update invlpg handler comment
KVM: VMX: move CR3/PDPTR update to vmx_set_cr3
KVM: remove duplicated task_switch check
KVM: powerpc: Fix BUILD_BUG_ON condition
KVM: VMX: Use shared msr infrastructure
...Trivial conflicts due to new Kconfig options in arch/Kconfig and kernel/Makefile
08 Nov, 2009
1 commit
-
This patch rebase the implementation of the breakpoints API on top of
perf events instances.Each breakpoints are now perf events that handle the
register scheduling, thread/cpu attachment, etc..The new layering is now made as follows:
ptrace kgdb ftrace perf syscall
\ | / /
\ | / /
/
Core breakpoint API /
/
| /
| /Breakpoints perf events
|
|Breakpoints PMU ---- Debug Register constraints handling
(Part of core breakpoint API)
|
|Hardware debug registers
Reasons of this rewrite:
- Use the centralized/optimized pmu registers scheduling,
implying an easier arch integration
- More powerful register handling: perf attributes (pinned/flexible
events, exclusive/non-exclusive, tunable period, etc...)Impact:
- New perf ABI: the hardware breakpoints counters
- Ptrace breakpoints setting remains tricky and still needs some per
thread breakpoints references.Todo (in the order):
- Support breakpoints perf counter events for perf tools (ie: implement
perf_bpcounter_event())
- Support from perf toolsChanges in v2:
- Follow the perf "event " rename
- The ptrace regression have been fixed (ptrace breakpoint perf events
weren't released when a task ended)
- Drop the struct hw_breakpoint and store generic fields in
perf_event_attr.
- Separate core and arch specific headers, drop
asm-generic/hw_breakpoint.h and create linux/hw_breakpoint.h
- Use new generic len/type for breakpoint
- Handle off case: when breakpoints api is not supported by an archChanges in v3:
- Fix broken CONFIG_KVM, we need to propagate the breakpoint api
changes to kvm when we exit the guest and restore the bp registers
to the host.Changes in v4:
- Drop the hw_breakpoint_restore() stub as it is only used by KVM
- EXPORT_SYMBOL_GPL hw_breakpoint_restore() as KVM can be built as a
module
- Restore the breakpoints unconditionally on kvm guest exit:
TIF_DEBUG_THREAD doesn't anymore cover every cases of running
breakpoints and vcpu->arch.switch_db_regs might not always be
set when the guest used debug registers.
(Waiting for a reliable optimization)Changes in v5:
- Split-up the asm-generic/hw-breakpoint.h moving to
linux/hw_breakpoint.h into a separate patch
- Optimize the breakpoints restoring while switching from kvm guest
to host. We only want to restore the state if we have active
breakpoints to the host, otherwise we don't care about messed-up
address registers.
- Add asm/hw_breakpoint.h to Kbuild
- Fix bad breakpoint type in trace_selftest.cChanges in v6:
- Fix wrong header inclusion in trace.h (triggered a build
error with CONFIG_FTRACE_SELFTESTSigned-off-by: Frederic Weisbecker
Cc: Prasad
Cc: Alan Stern
Cc: Peter Zijlstra
Cc: Arnaldo Carvalho de Melo
Cc: Steven Rostedt
Cc: Ingo Molnar
Cc: Jan Kiszka
Cc: Jiri Slaby
Cc: Li Zefan
Cc: Avi Kivity
Cc: Paul Mackerras
Cc: Mike Galbraith
Cc: Masami Hiramatsu
Cc: Paul Mundt
18 Oct, 2009
1 commit
-
Conflicts:
kernel/Makefile
kernel/trace/Makefile
kernel/trace/trace.h
samples/MakefileMerge reason: We need to be uptodate with the perf events development
branch because we plan to rewrite the breakpoints API on top of
perf events.
02 Oct, 2009
1 commit
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Add a general per-cpu notifier that is called whenever the kernel is
about to return to userspace. The notifier uses a thread_info flag
and existing checks, so there is no impact on user return or context
switch fast paths.This will be used initially to speed up KVM task switching by lazily
updating MSRs.Signed-off-by: Avi Kivity
LKML-Reference:
Signed-off-by: H. Peter Anvin
18 Sep, 2009
1 commit
-
commit 85bac32c4a52c592b857f2c360cc5ec93a097d70
ring-buffer: only enable ring_buffer_swap_cpu when needed
broke oprofile (at least on s390, but likely on all platforms).this patch lets oprofile select RING_BUFER_ALLOW_SWAP to make
ring_buffer_swap_cpu usable for oprofile.Signed-off-by: Christian Borntraeger
LKML-Reference:
Cc: Ingo Molnar
Cc: Robert Richter
Signed-off-by: Steven Rostedt
15 Sep, 2009
1 commit
-
Conflicts:
arch/x86/kernel/process_64.cSemantic conflict fixed in:
arch/x86/kvm/x86.cSigned-off-by: Ingo Molnar
07 Sep, 2009
1 commit
-
Conflicts:
arch/Kconfig
kernel/trace/trace.hMerge reason: resolve the conflicts, plus adopt to the new
ring-buffer APIs.Signed-off-by: Ingo Molnar
20 Jul, 2009
1 commit
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The number of hardware counters is limited. The multiplexing feature
enables OProfile to gather more events than counters are provided by
the hardware. This is realized by switching between events at an user
specified time interval.A new file (/dev/oprofile/time_slice) is added for the user to specify
the timer interval in ms. If the number of events to profile is higher
than the number of hardware counters available, the patch will
schedule a work queue that switches the event counter and re-writes
the different sets of values into it. The switching mechanism needs to
be implemented for each architecture to support multiplexing. This
patch only implements AMD CPU support, but multiplexing can be easily
extended for other models and architectures.There are follow-on patches that rework parts of this patch.
Signed-off-by: Jason Yeh
Signed-off-by: Robert Richter
19 Jun, 2009
1 commit
-
Enable the use of GCC's coverage testing tool gcov [1] with the Linux
kernel. gcov may be useful for:* debugging (has this code been reached at all?)
* test improvement (how do I change my test to cover these lines?)
* minimizing kernel configurations (do I need this option if the
associated code is never run?)The profiling patch incorporates the following changes:
* change kbuild to include profiling flags
* provide functions needed by profiling code
* present profiling data as files in debugfsNote that on some architectures, enabling gcc's profiling option
"-fprofile-arcs" for the entire kernel may trigger compile/link/
run-time problems, some of which are caused by toolchain bugs and
others which require adjustment of architecture code.For this reason profiling the entire kernel is initially restricted
to those architectures for which it is known to work without changes.
This restriction can be lifted once an architecture has been tested
and found compatible with gcc's profiling. Profiling of single files
or directories is still available on all platforms (see config help
text).[1] http://gcc.gnu.org/onlinedocs/gcc/Gcov.html
Signed-off-by: Peter Oberparleiter
Cc: Andi Kleen
Cc: Huang Ying
Cc: Li Wei
Cc: Michael Ellerman
Cc: Ingo Molnar
Cc: Heiko Carstens
Cc: Martin Schwidefsky
Cc: Rusty Russell
Cc: WANG Cong
Cc: Sam Ravnborg
Cc: Jeff Dike
Cc: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
03 Jun, 2009
1 commit
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This patch introduces the generic Hardware Breakpoint interfaces for both user
and kernel space requests.
This core Api handles the hardware breakpoints through new helpers. It
handles the user-space breakpoints and kernel breakpoints in front of
arch implementation.One can choose kernel wide breakpoints using the following helpers
and passing them a generic struct hw_breakpoint:- register_kernel_hw_breakpoint()
- unregister_kernel_hw_breakpoint()
- modify_kernel_hw_breakpoint()On the other side, you can choose per task breakpoints.
- register_user_hw_breakpoint()
- unregister_user_hw_breakpoint()
- modify_user_hw_breakpoint()[ fweisbec@gmail.com: fix conflict against perfcounter ]
Original-patch-by: Alan Stern
Signed-off-by: K.Prasad
Reviewed-by: Alan Stern
Signed-off-by: Frederic Weisbecker
10 Apr, 2009
1 commit
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Impact: performance regression fix for s390
The adaptive spinning mutexes will not always do what one would expect on
virtualized architectures like s390. Especially the cpu_relax() loop in
mutex_spin_on_owner might hurt if the mutex holding cpu has been scheduled
away by the hypervisor.We would end up in a cpu_relax() loop when there is no chance that the
state of the mutex changes until the target cpu has been scheduled again by
the hypervisor.For that reason we should change the default behaviour to no-spin on s390.
We do have an instruction which allows to yield the current cpu in favour of
a different target cpu. Also we have an instruction which allows us to figure
out if the target cpu is physically backed.However we need to do some performance tests until we can come up with
a solution that will do the right thing on s390.Signed-off-by: Heiko Carstens
Acked-by: Peter Zijlstra
Cc: Martin Schwidefsky
Cc: Christian Borntraeger
LKML-Reference:
Signed-off-by: Ingo Molnar
02 Apr, 2009
1 commit
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Conflicts:
include/linux/slub_def.h
lib/Kconfig.debug
mm/slob.c
mm/slub.c
06 Mar, 2009
1 commit
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Clean up menu structure, introduce TRACING_SUPPORT switch that signals
whether an architecture supports various instrumentation mechanisms.Signed-off-by: Ingo Molnar
05 Mar, 2009
1 commit
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Impact: add a Kconfig entry for DMA-API debugging
Signed-off-by: Joerg Roedel
