Add a generic qualifier for transaction events, as a new sample
type that returns a flag word. This is particularly useful
for qualifying aborts: to distinguish aborts which happen
due to asynchronous events (like conflicts caused by another
CPU) versus instructions that lead to an abort.
The tuning strategies are very different for those cases,
so it's important to distinguish them easily and early.
Since it's inconvenient and inflexible to filter for this
in the kernel we report all the events out and allow
some post processing in user space.
The flags are based on the Intel TSX events, but should be fairly
generic and mostly applicable to other HTM architectures too. In addition
to various flag words there's also reserved space to report an
program supplied abort code. For TSX this is used to distinguish specific
classes of aborts, like a lock busy abort when doing lock elision.
Flags:
Elision and generic transactions (ELISION vs TRANSACTION)
(HLE vs RTM on TSX; IBM etc. would likely only use TRANSACTION)
Aborts caused by current thread vs aborts caused by others (SYNC vs ASYNC)
Retryable transaction (RETRY)
Conflicts with other threads (CONFLICT)
Transaction write capacity overflow (CAPACITY WRITE)
Transaction read capacity overflow (CAPACITY READ)
Transactions implicitely aborted can also return an abort code.
This can be used to signal specific events to the profiler. A common
case is abort on lock busy in a RTM eliding library (code 0xff)
To handle this case we include the TSX abort code
Common example aborts in TSX would be:
- Data conflict with another thread on memory read.
Flags: TRANSACTION|ASYNC|CONFLICT
- executing a WRMSR in a transaction. Flags: TRANSACTION|SYNC
- HLE transaction in user space is too large
Flags: ELISION|SYNC|CAPACITY-WRITE
The only flag that is somewhat TSX specific is ELISION.
This adds the perf core glue needed for reporting the new flag word out.
v2: Add MEM/MISC
v3: Move transaction to the end
v4: Separate capacity-read/write and remove misc
v5: Remove _SAMPLE. Move abort flags to 32bit. Rename
transaction to txn
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add support to perf stat to print the basic transactional execution statistics:
Total cycles, Cycles in Transaction, Cycles in aborted transsactions
using the in_tx and in_tx_checkpoint qualifiers.
Transaction Starts and Elision Starts, to compute the average transaction
length.
This is a reasonable overview over the success of the transactions.
Also support architectures that have a transaction aborted cycles
counter like POWER8. Since that is awkward to handle in the kernel
abstract handle both cases here.
Enable with a new --transaction / -T option.
This requires measuring these events in a group, since they depend on each
other.
This is implemented by using TM sysfs events exported by the kernel
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnaldo Carvalho de Melo <acme@infradead.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1377128846-977-5-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently the cap_user_time_zero capability has different tests than
cap_user_time; even though they expose the exact same data.
Switch from CONSTANT && NONSTOP to sched_clock_stable to also deal
with multi cabinet machines and drop the tsc_disabled() check.. non of
this will work sanely without tsc anyway.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-nmgn0j0muo1r4c94vlfh23xy@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While auditing the list_entry usage due to a trinity bug I found that
perf_pmu_migrate_context violates the rules for
perf_event::event_entry.
The problem is that perf_event::event_entry is a RCU list element, and
hence we must wait for a full RCU grace period before re-using the
element after deletion.
Therefore the usage in perf_pmu_migrate_context() which re-uses the
entry immediately is broken. For now introduce another list_head into
perf_event for this specific usage.
This doesn't actually fix the trinity report because that never goes
through this code.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-mkj72lxagw1z8fvjm648iznw@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull drm fixes from Dave Airlie:
"Nothing too major, radeon still has some dpm changes for off by
default.
Radeon, intel, msm:
- radeon: a few more dpm fixes (still off by default), uvd fixes
- i915: runtime warn backtrace and regression fix
- msm: iommu changes fallout"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (27 commits)
drm/msm: use drm_gem_dumb_destroy helper
drm/msm: deal with mach/iommu.h removal
drm/msm: Remove iommu include from mdp4_kms.c
drm/msm: Odd PTR_ERR usage
drm/i915: Fix up usage of SHRINK_STOP
drm/radeon: fix hdmi audio on DCE3.0/3.1 asics
drm/i915: preserve pipe A quirk in i9xx_set_pipeconf
drm/i915/tv: clear adjusted_mode.flags
drm/i915/dp: increase i2c-over-aux retry interval on AUX DEFER
drm/radeon/cik: fix overflow in vram fetch
drm/radeon: add missing hdmi callbacks for rv6xx
drm/i915: Use a temporary va_list for two-pass string handling
drm/radeon/uvd: lower msg&fb buffer requirements on UVD3
drm/radeon: disable tests/benchmarks if accel is disabled
drm/radeon: don't set default clocks for SI when DPM is disabled
drm/radeon/dpm/ci: filter clocks based on voltage/clk dep tables
drm/radeon/dpm/si: filter clocks based on voltage/clk dep tables
drm/radeon/dpm/ni: filter clocks based on voltage/clk dep tables
drm/radeon/dpm/btc: filter clocks based on voltage/clk dep tables
drm/radeon/dpm: fetch the max clk from voltage dep tables helper
...
This reverts commit de95ab5364.
Markus Trippelsdorf reported that this commit broke 'perf top':
> I just see a gray screen with no text at all. Sometimes the
> following error messages are printed:
>
> *** Error in `perf': invalid fastbin entry (free): 0x00000000029b18c0
> ***
> *** Error in `perf': malloc(): memory corruption (fast): 0x0000000000ee0b10 ***
While this code is fixable, the commit itself fails on several levels:
- it should have been a separate helper function
- why the heck does it do strchr() twice
- it casts a const char * over into char *
- sloppy style
- it's not even a regression fix!
So lets revert it and re-try the patch in v3.13.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A small fix + deal with fallout of iommu changes + use new
drm_gem_dumb_destroy helper.
* 'msm-fixes-3.12-rc2' of git://people.freedesktop.org/~robclark/linux:
drm/msm: use drm_gem_dumb_destroy helper
drm/msm: deal with mach/iommu.h removal
drm/msm: Remove iommu include from mdp4_kms.c
drm/msm: Odd PTR_ERR usage
Pull scheduler, timer and x86 fixes from Ingo Molnar:
- A context tracking ARM build and functional fix
- A handful of ARM clocksource/clockevent driver fixes
- An AMD microcode patch level sysfs reporting fixlet
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
arm: Fix build error with context tracking calls
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource: em_sti: Set cpu_possible_mask to fix SMP broadcast
clocksource: of: Respect device tree node status
clocksource: exynos_mct: Set IRQ affinity when the CPU goes online
arm: clocksource: mvebu: Use the main timer as clock source from DT
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/microcode/AMD: Fix patch level reporting for family 15h
Pull perf fixes from Ingo Molnar:
"A couple of tooling fixlets and a PMU detection printout fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Fix PMU detection printout when no PMU is detected
perf symbols: Demangle cloned functions
perf machine: Fix path unpopulated in machine__create_modules()
perf tools: Explicitly add libdl dependency
perf probe: Fix probing symbols with optimization suffix
perf trace: Add mmap2 handler
perf kmem: Make it work again on non NUMA machines
Pull xfs bugfixes from Ben Myers:
- fix for directory node collapse regression
- fix for recovery over stale on disk structures
- fix for eofblocks ioctl
- fix asserts in xfs_inode_free
- lock the ail before removing an item from it
* tag 'xfs-for-linus-v3.12-rc3' of git://oss.sgi.com/xfs/xfs:
xfs: fix node forward in xfs_node_toosmall
xfs: log recovery lsn ordering needs uuid check
xfs: fix XFS_IOC_FREE_EOFBLOCKS definition
xfs: asserting lock not held during freeing not valid
xfs: lock the AIL before removing the buffer item
Pull i2c fixes from Wolfram Sang:
"Some driver bugfixes for the I2C subsystem"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: ismt: initialize DMA buffer
i2c: designware: 10-bit addressing mode enabling if I2C_DYNAMIC_TAR_UPDATE is set
i2c: mv64xxx: Do not use writel_relaxed()
i2c: mv64xxx: Fix some build warnings
i2c: s3c2410: fix clk_disable/clk_unprepare WARNings
Pull ACPI and power management fixes from Rafael Wysocki:
"These fix one recent cpufreq regression, a few older bugs that may
harm users and a kerneldoc typo.
Specifics:
1) After the recent locking changes in the cpufreq core it is
possible to trigger BUG_ON(!policy) in lock_policy_rwsem_read() if
cpufreq_get() is called before registering a cpufreq driver. Fix
from Viresh Kumar.
2) If intel_pstate has been loaded already, it doesn't make sense to
do anything in acpi_cpufreq_init() and moreover doing something in
there in that case may be harmful, so make that function return
immediately if another cpufreq driver is already present. From
Yinghai Lu.
3) The ACPI IPMI driver sometimes attempts to acquire a mutex from
interrupt context, which can be avoided by replacing that mutex
with a spinlock. From Lv Zheng.
4) A NULL pointer may be dereferenced by the exynos5440 cpufreq
driver if a memory allocation made by it fails. Fix from Sachin
Kamat.
5) Hanjun Guo's commit fixes a typo in the kerneldoc comment
documenting acpi_bus_unregister_driver()"
* tag 'pm+acpi-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / scan: fix typo in comments of acpi_bus_unregister_driver()
cpufreq: exynos5440: Fix potential NULL pointer dereference
cpufreq: check cpufreq driver is valid and cpufreq isn't disabled in cpufreq_get()
acpi-cpufreq: skip loading acpi_cpufreq after intel_pstate
ACPI / IPMI: Fix atomic context requirement of ipmi_msg_handler()
Ben Herrenschmidt found that commit 928bea9648 ("PCI: Delay enabling
bridges until they're needed") breaks PCI in some powerpc environments.
The reason is that the PCIe port driver will call pci_enable_device() on
the bridge, so the device is enabled, but skips pci_set_master because
pcie_port_auto and no acpi on powerpc.
Because of that, pci_enable_bridge() later on (called as a result of the
child device driver doing pci_enable_device) will see the bridge as
already enabled and will not call pci_set_master() on it.
Fixed by add checking in pci_enable_bridge, and call pci_set_master
if driver skip that.
That will make the code more robot and wade off problem for missing
pci_set_master in drivers.
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull s390 lockref enablement from Heiko Carstens:
"Enabling the new lockless lockref variant on s390 would have been
trivial until Tony Luck added a cpu_relax() call into the
CMPXCHG_LOOP(), with commit d472d9d98b ("lockref: Relax in cmpxchg
loop")
As already mentioned cpu_relax() is very expensive on s390 since it
yields() the current virtual cpu. So we are talking of several
thousand cycles. Considering this enabling the lockless lockref
variant would contradict the intention of the new semantics. And also
some quick measurements show performance regressions of 50% and more.
Simply removing the cpu_relax() call again seems also not very
desireable since Waiman Long reported that for some workloads the call
improved performance by 5%."
* 'lockref' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: enable ARCH_USE_CMPXCHG_LOCKREF
lockref: use arch_mutex_cpu_relax() in CMPXCHG_LOOP()
mutex: replace CONFIG_HAVE_ARCH_MUTEX_CPU_RELAX with simple ifdef
Pull DeviceTree fixes from Rob Herring:
"Clean-up to fix some warnings for !OF builds and spelling fixes in
docs:
- Clean-up openrisc prom.h
- Fix warnings caused by of_irq.h ifdefs
- Spelling fix for Synopsys"
* tag 'devicetree-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
dts: Fix misspelling of Synopsys
of: clean-up ifdefs in of_irq.h
openrisc: clean-up prom.h
Pull ARM fixes from Russell King:
"Just a few relatively small ARM fixes found since the last merge
window, nothing too exciting"
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7837/3: fix Thumb-2 bug in AES assembler code
ARM: only allow kernel mode neon with AEABI
ARM: 7839/1: entry: fix tracing of ARM-private syscalls
ARM: 7836/1: add __get_user_unaligned/__put_user_unaligned
This patch adds code to initialize the DMA buffer to compensate for
possible hardware data corruption.
Signed-off-by: James Ralston <james.d.ralston@intel.com>
[wsa: changed to use 'sizeof']
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
We still need an API exported by msm iommu driver (but not visible in
any public header anymore). For now, just declare the prototype
ourselves, but when msm iommu driver provides a better option, use that
instead.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Ran into this cryptic PMU bootup log recently:
[ 0.124047] Performance Events:
[ 0.125000] smpboot: ...
Turns out we print this if no PMU is detected. Fall back to
the right condition so that the following is printed:
[ 0.122381] Performance Events: no PMU driver, software events only.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/n/tip-u2fwaUffakjp0qkpRfqljgsn@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andi Kleen
Knut Petersen
Ingo Molnar
Peter Zijlstra
Linus Torvalds
Dave Airlie
Yinghai Lu
Jean Delvare
James Ralston
Rob Clark