Pull ARM updates from Russell King:
- Major clean-up of the L2 cache support code. The existing mess was
becoming rather unmaintainable through all the additions that others
have done over time. This turns it into a much nicer structure, and
implements a few performance improvements as well.
- Clean up some of the CP15 control register tweaks for alignment
support, moving some code and data into alignment.c
- DMA properties for ARM, from Santosh and reviewed by DT people. This
adds DT properties to specify bus translations we can't discover
automatically, and to indicate whether devices are coherent.
- Hibernation support for ARM
- Make ftrace work with read-only text in modules
- add suspend support for PJ4B CPUs
- rework interrupt masking for undefined instruction handling, which
allows us to enable interrupts earlier in the handling of these
exceptions.
- support for big endian page tables
- fix stacktrace support to exclude stacktrace functions from the
trace, and add save_stack_trace_regs() implementation so that kprobes
can record stack traces.
- Add support for the Cortex-A17 CPU.
- Remove last vestiges of ARM710 support.
- Removal of ARM "meminfo" structure, finally converting us solely to
memblock to handle the early memory initialisation.
* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (142 commits)
ARM: ensure C page table setup code follows assembly code (part II)
ARM: ensure C page table setup code follows assembly code
ARM: consolidate last remaining open-coded alignment trap enable
ARM: remove global cr_no_alignment
ARM: remove CPU_CP15 conditional from alignment.c
ARM: remove unused adjust_cr() function
ARM: move "noalign" command line option to alignment.c
ARM: provide common method to clear bits in CPU control register
ARM: 8025/1: Get rid of meminfo
ARM: 8060/1: mm: allow sub-architectures to override PCI I/O memory type
ARM: 8066/1: correction for ARM patch 8031/2
ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation
ARM: 8065/1: remove last use of CONFIG_CPU_ARM710
ARM: 8062/1: Modify ldrt fixup handler to re-execute the userspace instruction
ARM: 8047/1: rwsem: use asm-generic rwsem implementation
ARM: l2c: trial at enabling some Cortex-A9 optimisations
ARM: l2c: add warnings for stuff modifying aux_ctrl register values
ARM: l2c: print a warning with L2C-310 caches if the cache size is modified
ARM: l2c: remove old .set_debug method
ARM: l2c: kill L2X0_AUX_CTRL_MASK before anyone else makes use of this
...
Pull perf updates from Ingo Molnar:
"The tooling changes maintained by Jiri Olsa until Arnaldo is on
vacation:
User visible changes:
- Add -F option for specifying output fields (Namhyung Kim)
- Propagate exit status of a command line workload for record command
(Namhyung Kim)
- Use tid for finding thread (Namhyung Kim)
- Clarify the output of perf sched map plus small sched command
fixes (Dongsheng Yang)
- Wire up perf_regs and unwind support for ARM64 (Jean Pihet)
- Factor hists statistics counts processing which in turn also fixes
several bugs in TUI report command (Namhyung Kim)
- Add --percentage option to control absolute/relative percentage
output (Namhyung Kim)
- Add --list-cmds to 'kmem', 'mem', 'lock' and 'sched', for use by
completion scripts (Ramkumar Ramachandra)
Development/infrastructure changes and fixes:
- Android related fixes for pager and map dso resolving (Michael
Lentine)
- Add libdw DWARF post unwind support for ARM (Jean Pihet)
- Consolidate types.h for ARM and ARM64 (Jean Pihet)
- Fix possible null pointer dereference in session.c (Masanari Iida)
- Cleanup, remove unused variables in map_switch_event() (Dongsheng
Yang)
- Remove nr_state_machine_bugs in perf latency (Dongsheng Yang)
- Remove usage of trace_sched_wakeup(.success) (Peter Zijlstra)
- Cleanups for perf.h header (Jiri Olsa)
- Consolidate types.h and export.h within tools (Borislav Petkov)
- Move u64_swap union to its single user's header, evsel.h (Borislav
Petkov)
- Fix for s390 to properly parse tracepoints plus test code
(Alexander Yarygin)
- Handle EINTR error for readn/writen (Namhyung Kim)
- Add a test case for hists filtering (Namhyung Kim)
- Share map_groups among threads of the same group (Arnaldo Carvalho
de Melo, Jiri Olsa)
- Making some code (cpu node map and report parse callchain callback)
global to be usable by upcomming changes (Don Zickus)
- Fix pmu object compilation error (Jiri Olsa)
Kernel side changes:
- intrusive uprobes fixes from Oleg Nesterov. Since the interface is
admin-only, and the bug only affects user-space ("any probed
jmp/call can kill the application"), we queued these fixes via the
development tree, as a special exception.
- more fuzzer motivated race fixes and related refactoring and
robustization.
- allow PMU drivers to be built as modules. (No actual module yet,
because the x86 Intel uncore module wasn't ready in time for this)"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (114 commits)
perf tools: Add automatic remapping of Android libraries
perf tools: Add cat as fallback pager
perf tests: Add a testcase for histogram output sorting
perf tests: Factor out print_hists_*()
perf tools: Introduce reset_output_field()
perf tools: Get rid of obsolete hist_entry__sort_list
perf hists: Reset width of output fields with header length
perf tools: Skip elided sort entries
perf top: Add --fields option to specify output fields
perf report/tui: Fix a bug when --fields/sort is given
perf tools: Add ->sort() member to struct sort_entry
perf report: Add -F option to specify output fields
perf tools: Call perf_hpp__init() before setting up GUI browsers
perf tools: Consolidate management of default sort orders
perf tools: Allow hpp fields to be sort keys
perf ui: Get rid of callback from __hpp__fmt()
perf tools: Consolidate output field handling to hpp format routines
perf tools: Use hpp formats to sort final output
perf tools: Support event grouping in hpp ->sort()
perf tools: Use hpp formats to sort hist entries
...
After instruction write into xol area, on ARM V7
architecture code need to flush dcache and icache to sync
them up for given set of addresses. Having just
'flush_dcache_page(page)' call is not enough - it is
possible to have stale instruction sitting in icache
for given xol area slot address.
Introduce arch_uprobe_ixol_copy weak function
that by default calls uprobes copy_to_page function and
than flush_dcache_page function and on ARM define new one
that handles xol slot copy in ARM specific way
flush_uprobe_xol_access function shares/reuses implementation
with/of flush_ptrace_access function and takes care of writing
instruction to user land address space on given variety of
different cache types on ARM CPUs. Because
flush_uprobe_xol_access does not have vma around
flush_ptrace_access was split into two parts. First that
retrieves set of condition from vma and common that receives
those conditions as flags.
Note ARM cache flush function need kernel address
through which instruction write happened, so instead
of using uprobes copy_to_page function changed
code to explicitly map page and do memcpy.
Note arch_uprobe_copy_ixol function, in similar way as
copy_to_user_page function, has preempt_disable/preempt_enable.
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Alexander noticed that we use RCU iteration on rb->event_list but do
not use list_{add,del}_rcu() to add,remove entries to that list, nor
do we observe proper grace periods when re-using the entries.
Merge ring_buffer_detach() into ring_buffer_attach() such that
attaching to the NULL buffer is detaching.
Furthermore, ensure that between any 'detach' and 'attach' of the same
event we observe the required grace period, but only when strictly
required. In effect this means that only ioctl(.request =
PERF_EVENT_IOC_SET_OUTPUT) will wait for a grace period, while the
normal initial attach and final detach will not be delayed.
This patch should, I think, do the right thing under all
circumstances, the 'normal' cases all should never see the extra grace
period, but the two cases:
1) PERF_EVENT_IOC_SET_OUTPUT on an event which already has a
ring_buffer set, will now observe the required grace period between
removing itself from the old and attaching itself to the new buffer.
This case is 'simple' in that both buffers are present in
perf_event_set_output() one could think an unconditional
synchronize_rcu() would be sufficient; however...
2) an event that has a buffer attached, the buffer is destroyed
(munmap) and then the event is attached to a new/different buffer
using PERF_EVENT_IOC_SET_OUTPUT.
This case is more complex because the buffer destruction does:
ring_buffer_attach(.rb = NULL)
followed by the ioctl() doing:
ring_buffer_attach(.rb = foo);
and we still need to observe the grace period between these two
calls due to us reusing the event->rb_entry list_head.
In order to make 2 happen we use Paul's latest cond_synchronize_rcu()
call.
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Reported-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140507123526.GD13658@twins.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The perf cpu offline callback takes down all cpu context
events and releases swhash->swevent_hlist.
This could race with task context software event being just
scheduled on this cpu via perf_swevent_add while cpu hotplug
code already cleaned up event's data.
The race happens in the gap between the cpu notifier code
and the cpu being actually taken down. Note that only cpu
ctx events are terminated in the perf cpu hotplug code.
It's easily reproduced with:
$ perf record -e faults perf bench sched pipe
while putting one of the cpus offline:
# echo 0 > /sys/devices/system/cpu/cpu1/online
Console emits following warning:
WARNING: CPU: 1 PID: 2845 at kernel/events/core.c:5672 perf_swevent_add+0x18d/0x1a0()
Modules linked in:
CPU: 1 PID: 2845 Comm: sched-pipe Tainted: G W 3.14.0+ #256
Hardware name: Intel Corporation Montevina platform/To be filled by O.E.M., BIOS AMVACRB1.86C.0066.B00.0805070703 05/07/2008
0000000000000009 ffff880077233ab8 ffffffff81665a23 0000000000200005
0000000000000000 ffff880077233af8 ffffffff8104732c 0000000000000046
ffff88007467c800 0000000000000002 ffff88007a9cf2a0 0000000000000001
Call Trace:
[<ffffffff81665a23>] dump_stack+0x4f/0x7c
[<ffffffff8104732c>] warn_slowpath_common+0x8c/0xc0
[<ffffffff8104737a>] warn_slowpath_null+0x1a/0x20
[<ffffffff8110fb3d>] perf_swevent_add+0x18d/0x1a0
[<ffffffff811162ae>] event_sched_in.isra.75+0x9e/0x1f0
[<ffffffff8111646a>] group_sched_in+0x6a/0x1f0
[<ffffffff81083dd5>] ? sched_clock_local+0x25/0xa0
[<ffffffff811167e6>] ctx_sched_in+0x1f6/0x450
[<ffffffff8111757b>] perf_event_sched_in+0x6b/0xa0
[<ffffffff81117a4b>] perf_event_context_sched_in+0x7b/0xc0
[<ffffffff81117ece>] __perf_event_task_sched_in+0x43e/0x460
[<ffffffff81096f1e>] ? put_lock_stats.isra.18+0xe/0x30
[<ffffffff8107b3c8>] finish_task_switch+0xb8/0x100
[<ffffffff8166a7de>] __schedule+0x30e/0xad0
[<ffffffff81172dd2>] ? pipe_read+0x3e2/0x560
[<ffffffff8166b45e>] ? preempt_schedule_irq+0x3e/0x70
[<ffffffff8166b45e>] ? preempt_schedule_irq+0x3e/0x70
[<ffffffff8166b464>] preempt_schedule_irq+0x44/0x70
[<ffffffff816707f0>] retint_kernel+0x20/0x30
[<ffffffff8109e60a>] ? lockdep_sys_exit+0x1a/0x90
[<ffffffff812a4234>] lockdep_sys_exit_thunk+0x35/0x67
[<ffffffff81679321>] ? sysret_check+0x5/0x56
Fixing this by tracking the cpu hotplug state and displaying
the WARN only if current cpu is initialized properly.
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: stable@vger.kernel.org
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1396861448-10097-1-git-send-email-jolsa@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Vince reported that using a large sample_period (one with bit 63 set)
results in wreckage since while the sample_period is fundamentally
unsigned (negative periods don't make sense) the way we implement
things very much rely on signed logic.
So limit sample_period to 63 bits to avoid tripping over this.
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/n/tip-p25fhunibl4y3qi0zuqmyf4b@git.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Instead of jumping through hoops to make sure to find (and exit) each
event, do it the simple straight fwd way.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-tij931199thfkys8vbnokdpf@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Primarily make perf_event_release_kernel() into put_event(), this will
allow kernel space to create per-task inherited events, and is safer
in general.
Also, document the free_event() assumptions.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-rk9pvr6e1d0559lxstltbztc@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit 38b435b16c ("perf: Fix tear-down of inherited group events")
states that we need to destroy groups for inherited events, but it
doesn't make any sense to not also destroy groups for normal events.
And while it usually makes no difference (the normal events won't
leak, and its very likely all the group events will die in quick
succession) it does make the code more consistent and closes a
potential hole for trouble.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-426egt8zmsm12d2q8k2xz4tt@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make sure all events in a group have the same inherit state. It was
possible for group leaders to have inherit set while sibling events
would not have inherit set.
In this case we'd still inherit the siblings, leading to some
non-fatal weirdness.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-r32tt8yldvic3jlcghd3g35u@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When removing a (sibling) event we do:
raw_spin_lock_irq(&ctx->lock);
perf_group_detach(event);
raw_spin_unlock_irq(&ctx->lock);
<hole>
perf_remove_from_context(event);
raw_spin_lock_irq(&ctx->lock);
...
raw_spin_unlock_irq(&ctx->lock);
Now, assuming the event is a sibling, it will be 'unreachable' for
things like ctx_sched_out() because that iterates the
groups->siblings, and we just unhooked the sibling.
So, if during <hole> we get ctx_sched_out(), it will miss the event
and not call event_sched_out() on it, leaving it programmed on the
PMU.
The subsequent perf_remove_from_context() call will find the ctx is
inactive and only call list_del_event() to remove the event from all
other lists.
Hereafter we can proceed to free the event; while still programmed!
Close this hole by moving perf_group_detach() inside the same
ctx->lock region(s) perf_remove_from_context() has.
The condition on inherited events only in __perf_event_exit_task() is
likely complete crap because non-inherited events are part of groups
too and we're tearing down just the same. But leave that for another
patch.
Most-likely-Fixes: e03a9a55b4 ("perf: Change close() semantics for group events")
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Much-staring-at-traces-by: Vince Weaver <vincent.weaver@maine.edu>
Much-staring-at-traces-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140505093124.GN17778@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch adds support for building PMU driver as module. It exports
the functions perf_pmu_{register,unregister}() and adds reference tracking
for the PMU driver module.
When the PMU driver is built as a module, each active event of the PMU
holds a reference to the driver module.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1395133004-23205-1-git-send-email-zheng.z.yan@intel.com
Cc: eranian@google.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently the error from arch_uprobe_post_xol() is silently ignored.
This doesn't look good and this can lead to the hard-to-debug problems.
1. Change handle_singlestep() to loudly complain and send SIGILL.
Note: this only affects x86, ppc/arm can't fail.
2. Change arch_uprobe_post_xol() to call arch_uprobe_abort_xol() and
avoid TF games if it is going to return an error.
This can help to to analyze the problem, if nothing else we should
not report ->ip = xol_slot in the core-file.
Note: this means that handle_riprel_post_xol() can be called twice,
but this is fine because it is idempotent.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
UPROBE_COPY_INSN, UPROBE_SKIP_SSTEP, and uprobe->flags must die. This
patch kills UPROBE_SKIP_SSTEP. I never understood why it was added;
not only it doesn't help, it harms.
It can only help to avoid arch_uprobe_skip_sstep() if it was already
called before and failed. But this is ugly, if we want to know whether
we can emulate this instruction or not we should do this analysis in
arch_uprobe_analyze_insn(), not when we hit this probe for the first
time.
And in fact this logic is simply wrong. arch_uprobe_skip_sstep() can
fail or not depending on the task/register state, if this insn can be
emulated but, say, put_user() fails we need to xol it this time, but
this doesn't mean we shouldn't try to emulate it when this or another
thread hits this bp next time.
And this is the actual reason for this change. We need to emulate the
"call" insn, but push(return-address) can obviously fail.
Per-arch notes:
x86: __skip_sstep() can only emulate "rep;nop". With this
change it will be called every time and most probably
for no reason.
This will be fixed by the next changes. We need to
change this suboptimal code anyway.
arm: Should not be affected. It has its own "bool simulate"
flag checked in arch_uprobe_skip_sstep().
ppc: Looks like, it can emulate almost everything. Does it
actually need to record the fact that emulate_step()
failed? Hopefully not. But if yes, it can add the ppc-
specific flag into arch_uprobe.
TODO: rename arch_uprobe_skip_sstep() to arch_uprobe_emulate_insn(),
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: David A. Long <dave.long@linaro.org>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Pull ARM changes from Russell King:
- Perf updates from Will Deacon:
- Support for Qualcomm Krait processors (run perf on your phone!)
- Support for Cortex-A12 (run perf stat on your FPGA!)
- Support for perf_sample_event_took, allowing us to automatically decrease
the sample rate if we can't handle the PMU interrupts quickly enough
(run perf record on your FPGA!).
- Basic uprobes support from David Long:
This patch series adds basic uprobes support to ARM. It is based on
patches developed earlier by Rabin Vincent. That approach of adding
hooks into the kprobes instruction parsing code was not well received.
This approach separates the ARM instruction parsing code in kprobes out
into a separate set of functions which can be used by both kprobes and
uprobes. Both kprobes and uprobes then provide their own semantic action
tables to process the results of the parsing.
- ARMv7M (microcontroller) updates from Uwe Kleine-König
- OMAP DMA updates (recently added Vinod's Ack even though they've been
sitting in linux-next for a few months) to reduce the reliance of
omap-dma on the code in arch/arm.
- SA11x0 changes from Dmitry Eremin-Solenikov and Alexander Shiyan
- Support for Cortex-A12 CPU
- Align support for ARMv6 with ARMv7 so they can cooperate better in a
single zImage.
- Addition of first AT_HWCAP2 feature bits for ARMv8 crypto support.
- Removal of IRQ_DISABLED from various ARM files
- Improved efficiency of virt_to_page() for single zImage
- Patch from Ulf Hansson to permit runtime PM callbacks to be available for
AMBA devices for suspend/resume as well.
- Finally kill asm/system.h on ARM.
* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (89 commits)
dmaengine: omap-dma: more consolidation of CCR register setup
dmaengine: omap-dma: move IRQ handling to omap-dma
dmaengine: omap-dma: move register read/writes into omap-dma.c
ARM: omap: dma: get rid of 'p' allocation and clean up
ARM: omap: move dma channel allocation into plat-omap code
ARM: omap: dma: get rid of errata global
ARM: omap: clean up DMA register accesses
ARM: omap: remove almost-const variables
ARM: omap: remove references to disable_irq_lch
dmaengine: omap-dma: cleanup errata 3.3 handling
dmaengine: omap-dma: provide register read/write functions
dmaengine: omap-dma: use cached CCR value when enabling DMA
dmaengine: omap-dma: move barrier to omap_dma_start_desc()
dmaengine: omap-dma: move clnk_ctrl setting to preparation functions
dmaengine: omap-dma: improve efficiency loading C.SA/C.EI/C.FI registers
dmaengine: omap-dma: consolidate clearing channel status register
dmaengine: omap-dma: move CCR buffering disable errata out of the fast path
dmaengine: omap-dma: provide register definitions
dmaengine: omap-dma: consolidate setup of CCR
dmaengine: omap-dma: consolidate setup of CSDP
...
Pull cgroup updates from Tejun Heo:
"A lot updates for cgroup:
- The biggest one is cgroup's conversion to kernfs. cgroup took
after the long abandoned vfs-entangled sysfs implementation and
made it even more convoluted over time. cgroup's internal objects
were fused with vfs objects which also brought in vfs locking and
object lifetime rules. Naturally, there are places where vfs rules
don't fit and nasty hacks, such as credential switching or lock
dance interleaving inode mutex and cgroup_mutex with object serial
number comparison thrown in to decide whether the operation is
actually necessary, needed to be employed.
After conversion to kernfs, internal object lifetime and locking
rules are mostly isolated from vfs interactions allowing shedding
of several nasty hacks and overall simplification. This will also
allow implmentation of operations which may affect multiple cgroups
which weren't possible before as it would have required nesting
i_mutexes.
- Various simplifications including dropping of module support,
easier cgroup name/path handling, simplified cgroup file type
handling and task_cg_lists optimization.
- Prepatory changes for the planned unified hierarchy, which is still
a patchset away from being actually operational. The dummy
hierarchy is updated to serve as the default unified hierarchy.
Controllers which aren't claimed by other hierarchies are
associated with it, which BTW was what the dummy hierarchy was for
anyway.
- Various fixes from Li and others. This pull request includes some
patches to add missing slab.h to various subsystems. This was
triggered xattr.h include removal from cgroup.h. cgroup.h
indirectly got included a lot of files which brought in xattr.h
which brought in slab.h.
There are several merge commits - one to pull in kernfs updates
necessary for converting cgroup (already in upstream through
driver-core), others for interfering changes in the fixes branch"
* 'for-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (74 commits)
cgroup: remove useless argument from cgroup_exit()
cgroup: fix spurious lockdep warning in cgroup_exit()
cgroup: Use RCU_INIT_POINTER(x, NULL) in cgroup.c
cgroup: break kernfs active_ref protection in cgroup directory operations
cgroup: fix cgroup_taskset walking order
cgroup: implement CFTYPE_ONLY_ON_DFL
cgroup: make cgrp_dfl_root mountable
cgroup: drop const from @buffer of cftype->write_string()
cgroup: rename cgroup_dummy_root and related names
cgroup: move ->subsys_mask from cgroupfs_root to cgroup
cgroup: treat cgroup_dummy_root as an equivalent hierarchy during rebinding
cgroup: remove NULL checks from [pr_cont_]cgroup_{name|path}()
cgroup: use cgroup_setup_root() to initialize cgroup_dummy_root
cgroup: reorganize cgroup bootstrapping
cgroup: relocate setting of CGRP_DEAD
cpuset: use rcu_read_lock() to protect task_cs()
cgroup_freezer: document freezer_fork() subtleties
cgroup: update cgroup_transfer_tasks() to either succeed or fail
cgroup: drop task_lock() protection around task->cgroups
cgroup: update how a newly forked task gets associated with css_set
...
Allow arches to decided to ignore a probe hit. ARM will use this to
only call handlers if the conditions to execute a conditionally executed
instruction are satisfied.
Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Use the ctx pmu instead of the event pmu.
When a group leader is a software event but the group contains
hardware events, the entire group is on the hardware PMU.
Using the hardware PMU for the transaction makes most sense since
that's the most expensive one to programm (and software PMUs generally
don't have TXN support anyway).
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-sctoo9t2f3nn2c9g568928q3@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently perf_branch_stack_sched_in iterates over the set of pmus,
checks that each pmu has a flush_branch_stack callback, then overwrites
the pmu before calling the callback. This is either redundant or broken.
In systems with a single hw pmu, pmu == cpuctx->ctx.pmu, and thus the
assignment is redundant.
In systems with multiple hw pmus (i.e. multiple pmus with task_ctx_nr ==
perf_hw_context) the pmus share the same perf_cpu_context. Thus the
assignment can cause one of the pmus to flush its branch stack
repeatedly rather than causing each of the pmus to flush their branch
stacks. Worse still, if only some pmus have the callback the assignment
can result in a branch to NULL.
This patch removes the redundant assignment.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1392054264-23570-3-git-send-email-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For some reason find_pmu_context() is defined as returning void * rather
than a __percpu struct perf_cpu_context *. As all the requisite types are
defined in advance there's no reason to keep it that way.
This patch modifies the prototype of pmu_find_context to return a
__percpu struct perf_cpu_context *.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1392054264-23570-2-git-send-email-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Drew Richardson reported that he could make the kernel go *boom* when hotplugging
while having perf events active.
It turned out that when you have a group event, the code in
__perf_event_exit_context() fails to remove the group siblings from
the context.
We then proceed with destroying and freeing the event, and when you
re-plug the CPU and try and add another event to that CPU, things go
*boom* because you've still got dead entries there.
Reported-by: Drew Richardson <drew.richardson@arm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/n/tip-k6v5wundvusvcseqj1si0oz0@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On Mon, Feb 10, 2014 at 08:45:16AM -0800, Dave Hansen wrote:
> The reason I coded this up was that NMIs were firing off so fast that
> nothing else was getting a chance to run. With this patch, at least the
> printk() would come out and I'd have some idea what was going on.
It will start spewing to early_printk() (which is a lot nicer to use
from NMI context too) when it fails to queue the IRQ-work because its
already enqueued.
It does have the false-positive for when two CPUs trigger the warn
concurrently, but that should be rare and some extra clutter on the
early printk shouldn't be a problem.
Cc: hpa@zytor.com
Cc: tglx@linutronix.de
Cc: dzickus@redhat.com
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: mingo@kernel.org
Fixes: 6a02ad66b2 ("perf/x86: Push the duration-logging printk() to IRQ context")
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140211150116.GO27965@twins.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If !NULL, @skip_css makes cgroup_taskset_for_each() skip the matching
css. The intention of the interface is to make it easy to skip css's
(cgroup_subsys_states) which already match the migration target;
however, this is entirely unnecessary as migration taskset doesn't
include tasks which are already in the target cgroup. Drop @skip_css
from cgroup_taskset_for_each().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
css_from_dir() returns the matching css (cgroup_subsys_state) given a
dentry and subsystem. The function doesn't pin the css before
returning and requires the caller to be holding RCU read lock or
cgroup_mutex and handling pinning on the caller side.
Given that users of the function are likely to want to pin the
returned css (both existing users do) and that getting and putting
css's are very cheap, there's no reason for the interface to be tricky
like this.
Rename css_from_dir() to css_tryget_from_dir() and make it try to pin
the found css and return it only if pinning succeeded. The callers
are updated so that they no longer do RCU locking and pinning around
the function and just use the returned css.
This will also ease converting cgroup to kernfs.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Calling printk() from NMI context is bad (TM), so move it to IRQ
context.
This also avoids the problem where the printk() time is measured by
the generic NMI duration goo and triggers a second warning.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-75dv35xf6dhhmeb7nq6fua31@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
cgroup_subsys is a bit messier than it needs to be.
* The name of a subsys can be different from its internal identifier
defined in cgroup_subsys.h. Most subsystems use the matching name
but three - cpu, memory and perf_event - use different ones.
* cgroup_subsys_id enums are postfixed with _subsys_id and each
cgroup_subsys is postfixed with _subsys. cgroup.h is widely
included throughout various subsystems, it doesn't and shouldn't
have claim on such generic names which don't have any qualifier
indicating that they belong to cgroup.
* cgroup_subsys->subsys_id should always equal the matching
cgroup_subsys_id enum; however, we require each controller to
initialize it and then BUG if they don't match, which is a bit
silly.
This patch cleans up cgroup_subsys names and initialization by doing
the followings.
* cgroup_subsys_id enums are now postfixed with _cgrp_id, and each
cgroup_subsys with _cgrp_subsys.
* With the above, renaming subsys identifiers to match the userland
visible names doesn't cause any naming conflicts. All non-matching
identifiers are renamed to match the official names.
cpu_cgroup -> cpu
mem_cgroup -> memory
perf -> perf_event
* controllers no longer need to initialize ->subsys_id and ->name.
They're generated in cgroup core and set automatically during boot.
* Redundant cgroup_subsys declarations removed.
* While updating BUG_ON()s in cgroup_init_early(), convert them to
WARN()s. BUGging that early during boot is stupid - the kernel
can't print anything, even through serial console and the trap
handler doesn't even link stack frame properly for back-tracing.
This patch doesn't introduce any behavior changes.
v2: Rebased on top of fe1217c4f3 ("net: net_cls: move cgroupfs
classid handling into core").
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Ingo Molnar <mingo@redhat.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Thomas Graf <tgraf@suug.ch>
triggers by Tom Zanussi. A trigger is a way to enable an action when an
event is hit. The actions are:
o trace on/off - enable or disable tracing
o snapshot - save the current trace buffer in the snapshot
o stacktrace - dump the current stack trace to the ringbuffer
o enable/disable events - enable or disable another event
Namhyung Kim added updates to the tracing uprobes code. Having the
uprobes add support for fetch methods.
The rest are various bug fixes with the new code, and minor ones for
the old code.
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Merge tag 'trace-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"This pull request has a new feature to ftrace, namely the trace event
triggers by Tom Zanussi. A trigger is a way to enable an action when
an event is hit. The actions are:
o trace on/off - enable or disable tracing
o snapshot - save the current trace buffer in the snapshot
o stacktrace - dump the current stack trace to the ringbuffer
o enable/disable events - enable or disable another event
Namhyung Kim added updates to the tracing uprobes code. Having the
uprobes add support for fetch methods.
The rest are various bug fixes with the new code, and minor ones for
the old code"
* tag 'trace-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (38 commits)
tracing: Fix buggered tee(2) on tracing_pipe
tracing: Have trace buffer point back to trace_array
ftrace: Fix synchronization location disabling and freeing ftrace_ops
ftrace: Have function graph only trace based on global_ops filters
ftrace: Synchronize setting function_trace_op with ftrace_trace_function
tracing: Show available event triggers when no trigger is set
tracing: Consolidate event trigger code
tracing: Fix counter for traceon/off event triggers
tracing: Remove double-underscore naming in syscall trigger invocations
tracing/kprobes: Add trace event trigger invocations
tracing/probes: Fix build break on !CONFIG_KPROBE_EVENT
tracing/uprobes: Add @+file_offset fetch method
uprobes: Allocate ->utask before handler_chain() for tracing handlers
tracing/uprobes: Add support for full argument access methods
tracing/uprobes: Fetch args before reserving a ring buffer
tracing/uprobes: Pass 'is_return' to traceprobe_parse_probe_arg()
tracing/probes: Implement 'memory' fetch method for uprobes
tracing/probes: Add fetch{,_size} member into deref fetch method
tracing/probes: Move 'symbol' fetch method to kprobes
tracing/probes: Implement 'stack' fetch method for uprobes
...
Unlike recent modern userspace API such as:
epoll_create1 (EPOLL_CLOEXEC), eventfd (EFD_CLOEXEC),
fanotify_init (FAN_CLOEXEC), inotify_init1 (IN_CLOEXEC),
signalfd (SFD_CLOEXEC), timerfd_create (TFD_CLOEXEC),
or the venerable general purpose open (O_CLOEXEC),
perf_event_open() syscall lack a flag to atomically set FD_CLOEXEC
(eg. close-on-exec) flag on file descriptor it returns to userspace.
The present patch adds a PERF_FLAG_FD_CLOEXEC flag to allow
perf_event_open() syscall to atomically set close-on-exec.
Having this flag will enable userspace to remove the file descriptor
from the list of file descriptors being inherited across exec,
without the need to call fcntl(fd, F_SETFD, FD_CLOEXEC) and the
associated race condition between the current thread and another
thread calling fork(2) then execve(2).
Links:
- Secure File Descriptor Handling (Ulrich Drepper, 2008)
http://udrepper.livejournal.com/20407.html
- Excuse me son, but your code is leaking !!! (Dan Walsh, March 2012)
http://danwalsh.livejournal.com/53603.html
- Notes in DMA buffer sharing: leak and security hole
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/dma-buf-sharing.txt?id=v3.13-rc3#n428
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/8c03f54e1598b1727c19706f3af03f98685d9fe6.1388952061.git.ydroneaud@opteya.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes a problem with the initialization of the
struct perf_event active_entry field. It is defined inside
an anonymous union and was initialized in perf_event_alloc()
using INIT_LIST_HEAD(). However at that time, we do not know
whether the event is going to use active_entry or hlist_entry (SW).
Or at last, we don't want to make that determination there.
The problem is that hlist and list_head are not initialized
the same way. One is okay with NULL (from kzmalloc), the other
needs to pointers to point to self.
This patch resolves this problem by dropping the union.
This will avoid problems later on, if someone starts using
active_entry or hlist_entry without verifying that they
actually overlap. This also solves the initialization
problem.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: ak@linux.intel.com
Cc: acme@redhat.com
Cc: jolsa@redhat.com
Cc: zheng.z.yan@intel.com
Cc: bp@alien8.de
Cc: vincent.weaver@maine.edu
Cc: maria.n.dimakopoulou@gmail.com
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1389176153-3128-2-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
uprobe_trace_print() and uprobe_perf_print() need to pass the additional
info to call_fetch() methods, currently there is no simple way to do this.
current->utask looks like a natural place to hold this info, but we need
to allocate it before handler_chain().
This is a bit unfortunate, perhaps we will find a better solution later,
but this is simple and should work right now.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Vince Weaver reports that, on all architectures apart from ARM,
PERF_EVENT_IOC_PERIOD doesn't actually update the period until the next
event fires. This is counter-intuitive behaviour and is better dealt
with in the core code.
This patch ensures that the period is forcefully reset when dealing with
such a request in the core code. A subsequent patch removes the
equivalent hack from the ARM back-end.
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1385560479-11014-1-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, only one PMU in a context gets disabled during unthrottling
and event_sched_{out,in}(), however, events in one context may belong to
different pmus, which results in PMUs being reprogrammed while they are
still enabled.
This means that mixed PMU use [which is rare in itself] resulted in
potentially completely unreliable results: corrupted events, bogus
results, etc.
This patch temporarily disables PMUs that correspond to
each event in the context while these events are being modified.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: http://lkml.kernel.org/r/1387196256-8030-1-git-send-email-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Remove a full barrier from the ring-buffer write path by relying on
a control dependency to order a LOAD -> STORE scenario.
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-8alv40z6ikk57jzbaobnxrjl@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch adds a new field to the struct perf_event.
It is intended to be used to chain events which are
active (enabled). It helps in the hardware layer
for PMUs which do not have actual counter restrictions, i.e.,
free running read-only counters. Active events are chained
as opposed to being tracked via the counter they use.
To save space we use a union with hlist_entry as both
are mutually exclusive (suggested by Jiri Olsa).
Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: acme@redhat.com
Cc: jolsa@redhat.com
Cc: zheng.z.yan@intel.com
Cc: bp@alien8.de
Cc: maria.n.dimakopoulou@gmail.com
Link: http://lkml.kernel.org/r/1384275531-10892-2-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1. Don't include asm/uprobes.h unconditionally, we only need
it if CONFIG_UPROBES.
2. Move the definition of "struct xol_area" into uprobes.c.
Perhaps we should simply kill struct uprobes_state, it buys
nothing.
3. Kill the dummy definition of uprobe_get_swbp_addr(), nobody
except handle_swbp() needs it.
4. Purely cosmetic, but move the decl of uprobe_get_swbp_addr()
up, close to other __weak helpers.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
arch_uprobe should be opaque as much as possible to the generic
code, but currently it assumes that insn/ixol must be u8[] of the
known size. Remove this unnecessary dependency, we can use "&" and
and sizeof() with the same effect.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
uprobe_task->vaddr is a bit strange. The generic code uses it only
to pass the additional argument to arch_uprobe_pre_xol(), and since
it is always equal to instruction_pointer() this looks even more
strange.
And both utask->vaddr and and utask->autask have the same scope,
they only have the meaning when the task executes the probed insn
out-of-line, so it is safe to reuse both in UTASK_RUNNING state.
This all means that logically ->vaddr belongs to arch_uprobe_task
and we should probably move it there, arch_uprobe_pre_xol() can
record instruction_pointer() itself.
OTOH, it is also used by uprobe_copy_process() and dup_xol_work()
for another purpose, this doesn't look clean and doesn't allow to
move this member into arch_uprobe_task.
This patch adds the union with 2 anonymous structs into uprobe_task.
The first struct is autask + vaddr, this way we "almost" move vaddr
into autask.
The second struct has 2 new members for uprobe_copy_process() paths:
->dup_xol_addr which can be used instead ->vaddr, and ->dup_xol_work
which can be used to avoid kmalloc() and simplify the code.
Note that this union will likely have another member(s), we need
something like "private_data_for_handlers" so that the tracing
handlers could use it to communicate with call_fetch() methods.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Currently we only allocate a single cpu hashtable for per-cpu
swevents; do away with this optimization for it is fragile in the face
of things like perf_pmu_migrate_context().
The easiest thing is to make sure all CPUs are consistent wrt state.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130913111447.GN31370@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add two trivial helpers list_next_entry() and list_prev_entry(), they
can have a lot of users including list.h itself. In fact the 1st one is
already defined in events/core.c and bnx2x_sp.c, so the patch simply
moves the definition to list.h.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eilon Greenstein <eilong@broadcom.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull perf updates from Ingo Molnar:
"As a first remark I'd like to note that the way to build perf tooling
has been simplified and sped up, in the future it should be enough for
you to build perf via:
cd tools/perf/
make install
(ie without the -j option.) The build system will figure out the
number of CPUs and will do a parallel build+install.
The various build system inefficiencies and breakages Linus reported
against the v3.12 pull request should now be resolved - please
(re-)report any remaining annoyances or bugs.
Main changes on the perf kernel side:
* Performance optimizations:
. perf ring-buffer code optimizations, by Peter Zijlstra
. perf ring-buffer code optimizations, by Oleg Nesterov
. x86 NMI call-stack processing optimizations, by Peter Zijlstra
. perf context-switch optimizations, by Peter Zijlstra
. perf sampling speedups, by Peter Zijlstra
. x86 Intel PEBS processing speedups, by Peter Zijlstra
* Enhanced hardware support:
. for Intel Ivy Bridge-EP uncore PMUs, by Zheng Yan
. for Haswell transactions, by Andi Kleen, Peter Zijlstra
* Core perf events code enhancements and fixes by Oleg Nesterov:
. for uprobes, if fork() is called with pending ret-probes
. for uprobes platform support code
* New ABI details by Andi Kleen:
. Report x86 Haswell TSX transaction abort cost as weight
Main changes on the perf tooling side (some of these tooling changes
utilize the above kernel side changes):
* 'perf report/top' enhancements:
. Convert callchain children list to rbtree, greatly reducing the
time taken for callchain processing, from Namhyung Kim.
. Add new COMM infrastructure, further improving histogram
processing, from Frédéric Weisbecker, one fix from Namhyung Kim.
. Add /proc/kcore based live-annotation improvements, including
build-id cache support, multi map 'call' instruction navigation
fixes, kcore address validation, objdump workarounds. From
Adrian Hunter.
. Show progress on histogram collapsing, that can take a long
time, from Namhyung Kim.
. Add --max-stack option to limit callchain stack scan in 'top'
and 'report', improving callchain processing when reducing the
stack depth is an option, from Waiman Long.
. Add new option --ignore-vmlinux for perf top, from Willy
Tarreau.
* 'perf trace' enhancements:
. 'perf trace' now can can use a 'perf probe' dynamic tracepoints
to hook into the userspace -> kernel pathname copy so that it
can map fds to pathnames without reading /proc/pid/fd/ symlinks.
From Arnaldo Carvalho de Melo.
. Show VFS path associated with fd in live sessions, using a
'vfs_getname' 'perf probe' created dynamic tracepoint or by
looking at /proc/pid/fd, from Arnaldo Carvalho de Melo.
. Add 'trace' beautifiers for lots of syscall arguments, from
Arnaldo Carvalho de Melo.
. Implement more compact 'trace' output by suppressing zeroed
args, from Arnaldo Carvalho de Melo.
. Show thread COMM by default in 'trace', from Arnaldo Carvalho de
Melo.
. Add option to show full timestamp in 'trace', from David Ahern.
. Add 'record' command in 'trace', to record raw_syscalls:*, from
David Ahern.
. Add summary option to dump syscall statistics in 'trace', from
David Ahern.
. Improve error messages in 'trace', providing hints about system
configuration steps needed for using it, from Ramkumar
Ramachandra.
. 'perf trace' now emits hints as to why tracing is not possible,
helping the user to setup the system to allow tracing in the
desired permission granularity, telling if the problem is due to
debugfs not being mounted or with not enough permission for
!root, /proc/sys/kernel/perf_event_paranoit value, etc. From
Arnaldo Carvalho de Melo.
* 'perf record' enhancements:
. Check maximum frequency rate for record/top, emitting better
error messages, from Jiri Olsa.
. 'perf record' code cleanups, from David Ahern.
. Improve write_output error message in 'perf record', from Adrian
Hunter.
. Allow specifying B/K/M/G unit to the --mmap-pages arguments,
from Jiri Olsa.
. Fix command line callchain attribute tests to handle the new
-g/--call-chain semantics, from Arnaldo Carvalho de Melo.
* 'perf kvm' enhancements:
. Disable live kvm command if timerfd is not supported, from David
Ahern.
. Fix detection of non-core features, from David Ahern.
* 'perf list' enhancements:
. Add usage to 'perf list', from David Ahern.
. Show error in 'perf list' if tracepoints not available, from
Pekka Enberg.
* 'perf probe' enhancements:
. Support "$vars" meta argument syntax for local variables,
allowing asking for all possible variables at a given probe
point to be collected when it hits, from Masami Hiramatsu.
* 'perf sched' enhancements:
. Address the root cause of that 'perf sched' stack initialization
build slowdown, by programmatically setting a big array after
moving the global variable back to the stack. Fix from Adrian
Hunter.
* 'perf script' enhancements:
. Set up output options for in-stream attributes, from Adrian
Hunter.
. Print addr by default for BTS in 'perf script', from Adrian
Juntmer
* 'perf stat' enhancements:
. Improved messages when doing profiling in all or a subset of
CPUs using a workload as the session delimitator, as in:
'perf stat --cpu 0,2 sleep 10s'
from Arnaldo Carvalho de Melo.
. Add units to nanosec-based counters in 'perf stat', from David
Ahern.
. Remove bogus info when using 'perf stat' -e cycles/instructions,
from Ramkumar Ramachandra.
* 'perf lock' enhancements:
. 'perf lock' fixes and cleanups, from Davidlohr Bueso.
* 'perf test' enhancements:
. Fixup PERF_SAMPLE_TRANSACTION handling in sample synthesizing
and 'perf test', from Adrian Hunter.
. Clarify the "sample parsing" test entry, from Arnaldo Carvalho
de Melo.
. Consider PERF_SAMPLE_TRANSACTION in the "sample parsing" test,
from Arnaldo Carvalho de Melo.
. Memory leak fixes in 'perf test', from Felipe Pena.
* 'perf bench' enhancements:
. Change the procps visible command-name of invididual benchmark
tests plus cleanups, from Ingo Molnar.
* Generic perf tooling infrastructure/plumbing changes:
. Separating data file properties from session, code
reorganization from Jiri Olsa.
. Fix version when building out of tree, as when using one of
these:
$ make help | grep perf
perf-tar-src-pkg - Build perf-3.12.0.tar source tarball
perf-targz-src-pkg - Build perf-3.12.0.tar.gz source tarball
perf-tarbz2-src-pkg - Build perf-3.12.0.tar.bz2 source tarball
perf-tarxz-src-pkg - Build perf-3.12.0.tar.xz source tarball
$
from David Ahern.
. Enhance option parse error message, showing just the help lines
of the options affected, from Namhyung Kim.
. libtraceevent updates from upstream trace-cmd repo, from Steven
Rostedt.
. Always use perf_evsel__set_sample_bit to set sample_type, from
Adrian Hunter.
. Memory and mmap leak fixes from Chenggang Qin.
. Assorted build fixes for from David Ahern and Jiri Olsa.
. Speed up and prettify the build system, from Ingo Molnar.
. Implement addr2line directly using libbfd, from Roberto Vitillo.
. Separate the GTK support in a separate libperf-gtk.so DSO, that
is only loaded when --gtk is specified, from Namhyung Kim.
. perf bash completion fixes and improvements from Ramkumar
Ramachandra.
. Support for Openembedded/Yocto -dbg packages, from Ricardo
Ribalda Delgado.
And lots and lots of other fixes and code reorganizations that did not
make it into the list, see the shortlog, diffstat and the Git log for
details!"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (300 commits)
uprobes: Fix the memory out of bound overwrite in copy_insn()
uprobes: Fix the wrong usage of current->utask in uprobe_copy_process()
perf tools: Remove unneeded include
perf record: Remove post_processing_offset variable
perf record: Remove advance_output function
perf record: Refactor feature handling into a separate function
perf trace: Don't relookup fields by name in each sample
perf tools: Fix version when building out of tree
perf evsel: Ditch evsel->handler.data field
uprobes: Export write_opcode() as uprobe_write_opcode()
uprobes: Introduce arch_uprobe->ixol
uprobes: Kill module_init() and module_exit()
uprobes: Move function declarations out of arch
perf/x86/intel: Add Ivy Bridge-EP uncore IRP box support
perf/x86/intel/uncore: Add filter support for IvyBridge-EP QPI boxes
perf: Factor out strncpy() in perf_event_mmap_event()
tools/perf: Add required memory barriers
perf: Fix arch_perf_out_copy_user default
perf: Update a stale comment
perf: Optimize perf_output_begin() -- address calculation
...
1. copy_insn() doesn't look very nice, all calculations are
confusing and it is not immediately clear why do we read
the 2nd page first.
2. The usage of inode->i_size is wrong on 32-bit machines.
3. "Instruction at end of binary" logic is simply wrong, it
doesn't handle the case when uprobe->offset > inode->i_size.
In this case "bytes" overflows, and __copy_insn() writes to
the memory outside of uprobe->arch.insn.
Yes, uprobe_register() checks i_size_read(), but this file
can be truncated after that. All i_size checks are racy, we
do this only to catch the obvious mistakes.
Change copy_insn() to call __copy_insn() in a loop, simplify
and fix the bytes/nbytes calculations.
Note: we do not care if we read extra bytes after inode->i_size
if we got the valid page. This is fine because the task gets the
same page after page-fault, and arch_uprobe_analyze_insn() can't
know how many bytes were actually read anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Commit aa59c53fd4 "uprobes: Change uprobe_copy_process() to dup
xol_area" has a stupid typo, we need to setup t->utask->vaddr but
the code wrongly uses current->utask.
Even with this bug dup_xol_work() works "in practice", but only
because get_unmapped_area(NULL, TASK_SIZE - PAGE_SIZE) likely
returns the same address every time.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
