Pull perf events changes for v3.4 from Ingo Molnar:
- New "hardware based branch profiling" feature both on the kernel and
the tooling side, on CPUs that support it. (modern x86 Intel CPUs
with the 'LBR' hardware feature currently.)
This new feature is basically a sophisticated 'magnifying glass' for
branch execution - something that is pretty difficult to extract from
regular, function histogram centric profiles.
The simplest mode is activated via 'perf record -b', and the result
looks like this in perf report:
$ perf record -b any_call,u -e cycles:u branchy
$ perf report -b --sort=symbol
52.34% [.] main [.] f1
24.04% [.] f1 [.] f3
23.60% [.] f1 [.] f2
0.01% [k] _IO_new_file_xsputn [k] _IO_file_overflow
0.01% [k] _IO_vfprintf_internal [k] _IO_new_file_xsputn
0.01% [k] _IO_vfprintf_internal [k] strchrnul
0.01% [k] __printf [k] _IO_vfprintf_internal
0.01% [k] main [k] __printf
This output shows from/to branch columns and shows the highest
percentage (from,to) jump combinations - i.e. the most likely taken
branches in the system. "branches" can also include function calls
and any other synchronous and asynchronous transitions of the
instruction pointer that are not 'next instruction' - such as system
calls, traps, interrupts, etc.
This feature comes with (hopefully intuitive) flat ascii and TUI
support in perf report.
- Various 'perf annotate' visual improvements for us assembly junkies.
It will now recognize function calls in the TUI and by hitting enter
you can follow the call (recursively) and back, amongst other
improvements.
- Multiple threads/processes recording support in perf record, perf
stat, perf top - which is activated via a comma-list of PIDs:
perf top -p 21483,21485
perf stat -p 21483,21485 -ddd
perf record -p 21483,21485
- Support for per UID views, via the --uid paramter to perf top, perf
report, etc. For example 'perf top --uid mingo' will only show the
tasks that I am running, excluding other users, root, etc.
- Jump label restructurings and improvements - this includes the
factoring out of the (hopefully much clearer) include/linux/static_key.h
generic facility:
struct static_key key = STATIC_KEY_INIT_FALSE;
...
if (static_key_false(&key))
do unlikely code
else
do likely code
...
static_key_slow_inc();
...
static_key_slow_inc();
...
The static_key_false() branch will be generated into the code with as
little impact to the likely code path as possible. the
static_key_slow_*() APIs flip the branch via live kernel code patching.
This facility can now be used more widely within the kernel to
micro-optimize hot branches whose likelihood matches the static-key
usage and fast/slow cost patterns.
- SW function tracer improvements: perf support and filtering support.
- Various hardenings of the perf.data ABI, to make older perf.data's
smoother on newer tool versions, to make new features integrate more
smoothly, to support cross-endian recording/analyzing workflows
better, etc.
- Restructuring of the kprobes code, the splitting out of 'optprobes',
and a corner case bugfix.
- Allow the tracing of kernel console output (printk).
- Improvements/fixes to user-space RDPMC support, allowing user-space
self-profiling code to extract PMU counts without performing any
system calls, while playing nice with the kernel side.
- 'perf bench' improvements
- ... and lots of internal restructurings, cleanups and fixes that made
these features possible. And, as usual this list is incomplete as
there were also lots of other improvements
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits)
perf report: Fix annotate double quit issue in branch view mode
perf report: Remove duplicate annotate choice in branch view mode
perf/x86: Prettify pmu config literals
perf report: Enable TUI in branch view mode
perf report: Auto-detect branch stack sampling mode
perf record: Add HEADER_BRANCH_STACK tag
perf record: Provide default branch stack sampling mode option
perf tools: Make perf able to read files from older ABIs
perf tools: Fix ABI compatibility bug in print_event_desc()
perf tools: Enable reading of perf.data files from different ABI rev
perf: Add ABI reference sizes
perf report: Add support for taken branch sampling
perf record: Add support for sampling taken branch
perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK
x86/kprobes: Split out optprobe related code to kprobes-opt.c
x86/kprobes: Fix a bug which can modify kernel code permanently
x86/kprobes: Fix instruction recovery on optimized path
perf: Add callback to flush branch_stack on context switch
perf: Disable PERF_SAMPLE_BRANCH_* when not supported
perf/x86: Add LBR software filter support for Intel CPUs
...
Pull irq/core changes for v3.4 from Ingo Molnar
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Remove paranoid warnons and bogus fixups
genirq: Flush the irq thread on synchronization
genirq: Get rid of unnecessary IRQTF_DIED flag
genirq: No need to check IRQTF_DIED before stopping a thread handler
genirq: Get rid of unnecessary irqaction field in task_struct
genirq: Fix incorrect check for forced IRQ thread handler
softirq: Reduce invoke_softirq() code duplication
genirq: Fix long-term regression in genirq irq_set_irq_type() handling
x86-32/irq: Don't switch to irq stack for a user-mode irq
Pull RCU changes for v3.4 from Ingo Molnar. The major features of this
series are:
- making RCU more aggressive about entering dyntick-idle mode in order
to improve energy efficiency
- converting a few more call_rcu()s to kfree_rcu()s
- applying a number of rcutree fixes and cleanups to rcutiny
- removing CONFIG_SMP #ifdefs from treercu
- allowing RCU CPU stall times to be set via sysfs
- adding CPU-stall capability to rcutorture
- adding more RCU-abuse diagnostics
- updating documentation
- fixing yet more issues located by the still-ongoing top-to-bottom
inspection of RCU, this time with a special focus on the CPU-hotplug
code path.
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
rcu: Stop spurious warnings from synchronize_sched_expedited
rcu: Hold off RCU_FAST_NO_HZ after timer posted
rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop
rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections
rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit()
rcu: Remove redundant check for rcu_head misalignment
PTR_ERR should be called before its argument is cleared.
rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdep
rcu: Trace only after NULL-pointer check
rcu: Call out dangers of expedited RCU primitives
rcu: Rework detection of use of RCU by offline CPUs
lockdep: Add CPU-idle/offline warning to lockdep-RCU splat
rcu: No interrupt disabling for rcu_prepare_for_idle()
rcu: Move synchronize_sched_expedited() to rcutree.c
rcu: Check for illegal use of RCU from offlined CPUs
rcu: Update stall-warning documentation
rcu: Add CPU-stall capability to rcutorture
rcu: Make documentation give more realistic rcutorture duration
rcutorture: Permit holding off CPU-hotplug operations during boot
rcu: Print scheduling-clock information on RCU CPU stall-warning messages
...
This allows us to turn on/off the dprintk() debugging interfaces for
those distributions that don't ship the 'rpcdebug' utility.
It also allows us to add Kbuild dependencies. Specifically, we already
know that dprintk() in general relies on CONFIG_SYSCTL. Now it turns out
that the NFS dprintks depend on CONFIG_CRC32 after we added support
for the filehandle hash.
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The tracing_on/off() declarations were under CONFIG_RING_BUFFER, but
the functions are now only defined under CONFIG_TRACING as they are
specific to ftrace and not the ring buffer.
But the declarations were still defined under the ring buffer and
this caused the build to fail when CONFIG_RING_BUFFER was set but
CONFIG_TRACING was not.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
toshiba_acpi needs to execute an AML method within the EC namespace
to make hotkeys work on some platforms. Provide an interface to
allow it to easily get a handle to the EC namespace for this purpose.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
All production devices operate in the Oaktrail configuration with legacy PC
elements present and an ACPI BIOS. Continue stripping out the Moorestown
elements from the tree leaving Medfield.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
TPS65090 is a Texas Instrument PMIC. It contains 3 Step-Down converters, 2
always on LDO's and 7 current limited load switches.
Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
[swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
For backward compatibility, we still keep the deprecated form,
and will warn the users if they still use the deprecated one, like this:
drivers/block/drbd/drbd_bitmap.c: In function ‘bm_page_io_async’:
drivers/block/drbd/drbd_bitmap.c:973:3: warning: ‘kmap_atomic_deprecated’ is deprecated (declared at /home/wangcong/linux-2.6/include/linux/highmem.h:124)
drivers/block/drbd/drbd_bitmap.c:977:3: warning: ‘kunmap_atomic_deprecated’ is deprecated (declared at /home/wangcong/linux-2.6/include/linux/highmem.h:144)
Thanks to Nick Bowler for the cpp trick!
Cc: Cesar Eduardo Barros <cesarb@cesarb.net>
Cc: Nick Bowler <nbowler@elliptictech.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Cong Wang <amwang@redhat.com>
As kvm_notify_acked_irq calls kvm_assigned_dev_ack_irq under
rcu_read_lock, we cannot use a mutex in the latter function. Switch to a
spin lock to address this.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
* tag 'drm-intel-next-2012-03-01' of git://people.freedesktop.org/~danvet/drm-intel:
drm/i915: Only clear the GPU domains upon a successful finish
drm/i915: reenable gmbus on gen3+ again
drm/i915: i2c: unconditionally set up gpio fallback
drm/i915: merge gmbus and gpio i2c adpater into one
drm/i915: merge struct intel_gpio into struct intel_gmbus
i2c: export bit-banging algo functions
drm/nouveau: do a better job at hiding the NIH i2c bit-banging algo
drm/i915: add dev_priv to intel_gmbus
drm/i915: Fix single msg gmbus_xfers writes
drm/i915: error_buffer->ring should be signed
drm/i915: Silence the error message from i915_wait_request()
drm/i915: use the new hdmi_force_audio enum more
drm/i915: No need to search again after retiring requests
drm/i915: Only bump refcnt on objects scheduled for eviction
drm/i915/bios: Downgrade the "signature missing" DRM_ERROR to debug
drm/i915: Ignore LVDS on hp t5745 and hp st5747 thin client
drm/i915: Fixes distorted external screen image on HP 2730p
Some of buttons, like power-on key or onkey, may only generate interrupts
when pressed and not actually be mapped as gpio in the system. Allow
setting gpio to invalid value and specify IRQ instead to support such
keys. The debounce timer is used not to debounce but to ignore new IRQs
coming while button is kept pressed.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This patch adds support for TI's CPSW driver.
The three port switch gigabit ethernet subsystem provides ethernet packet
communication and can be configured as an ethernet switch. Supports
10/100/1000 Mbps.
Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Signed-off-by: Sriramakrishnan A G <srk@ti.com>
Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is related to fixing the bug of dropping FCoE frames when disabling tx ip
checksum by 'ethtool -K ethx tx off'. The FCoE protocol stack driver would
use CHECKSUM_UNNECESSARY on tx path instead of CHECKSUM_PARTIAL (as indicated in
the 2/2 of this series). To do so, netif_needs_gso() has to be changed here to
not do gso for both CHECKSUM_PARTIAL and CHECKSUM_UNNECESSARY.
Ref. to original discussion thread:
http://patchwork.ozlabs.org/patch/146567/
Signed-off-by: Yi Zou <yi.zou@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With increasing receive window sizes, but speed of light not improved
that much, out of order queue can contain a huge number of skbs, waiting
to be moved to receive_queue when missing packets can fill the holes.
Some devices happen to use fat skbs (truesize of 4096 + sizeof(struct
sk_buff)) to store regular (MTU <= 1500) frames. This makes highly
probable sk_rmem_alloc hits sk_rcvbuf limit, which can be 4Mbytes in
many cases.
When limit is hit, tcp stack calls tcp_collapse_ofo_queue(), a true
latency killer and cpu cache blower.
Doing the coalescing attempt each time we add a frame in ofo queue
permits to keep memory use tight and in many cases avoid the
tcp_collapse() thing later.
Tested on various wireless setups (b43, ath9k, ...) known to use big skb
truesize, this patch removed the "packets collapsed in receive queue due
to low socket buffer" I had before.
This also reduced average memory used by tcp sockets.
With help from Neal Cardwell.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: H.K. Jerry Chu <hkchu@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the VIDIOC_G/S_SELECTION ioctls documentation more consistent
with the rest of media Docbook, use capital letters where necessary
and correct few minor errors.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
TWL specific changes, cross-merged with OMAP due to arch/arm wanting to
use the new ability to override the voltage set and get operations to
support the in-CPU voltage management. The other changes are minor
fixes, the addition of a few new regulators and device tree support.
* tag 'v3.3': (1646 commits)
Linux 3.3
Don't limit non-nested epoll paths
netfilter: ctnetlink: fix race between delete and timeout expiration
ipv6: Don't dev_hold(dev) in ip6_mc_find_dev_rcu.
nilfs2: fix NULL pointer dereference in nilfs_load_super_block()
nilfs2: clamp ns_r_segments_percentage to [1, 99]
afs: Remote abort can cause BUG in rxrpc code
afs: Read of file returns EBADMSG
C6X: remove dead code from entry.S
wimax/i2400m: fix erroneous NETDEV_TX_BUSY use
net/hyperv: fix erroneous NETDEV_TX_BUSY use
net/usbnet: reserve headroom on rx skbs
bnx2x: fix memory leak in bnx2x_init_firmware()
bnx2x: fix a crash on corrupt firmware file
sch_sfq: revert dont put new flow at the end of flows
ipv6: fix icmp6_dst_alloc()
MAINTAINERS: Add Serge as maintainer of capabilities
drivers/video/backlight/s6e63m0.c: fix corruption storing gamma mode
MAINTAINERS: add entry for exynos mipi display drivers
MAINTAINERS: fix link to Gustavo Padovans tree
...
