We just need to check if a 'policy' is already present for the cpu we are
adding. We don't need to take all the locks and do kobject usage updates. Use
the light-weight cpufreq_cpu_get_raw() routine instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

There is no need of this separate variable, use 'policy' instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

These are messing up more than the benefit they provide. It isn't
a lot of code anyway, that we will compile without them.

Kill them.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

We should first check if a cpufreq driver is already registered or not
before updating driver_data->flags.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

There is no point finding out the 'policy' again within __cpufreq_get()
when all the callers already have it. Just make them pass policy instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

There is no point finding out the 'policy' again within cpufreq_out_of_sync()
when all the callers already have it. Just make them pass policy instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Either we can be setpolicy or target type, nothing else. And so the
else part of setpolicy will automatically be of has_target() type.
And so we don't need to check it again.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove unnecessary from find_governor's name.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

There are two 'if' blocks here, checking for !cpufreq_driver->setpolicy and
has_target(). Both are actually doing the same thing, merge them.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

No need of an unnecessary line break.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

We can live without it and so we should.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

It doesn't make any sense at all and is a leftover of some earlier commit.
Remove it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

We should stop cpufreq governors when we shut down the system.  If we
don't do this, we can end up with this deadlock:

1. cpufreq governor may be running on a CPU other than CPU0.
2. In machine_restart() we call smp_send_stop() which stops CPUs.
   If one of these CPUs was actively running a cpufreq governor
   then it may have the mutex / spinlock needed to access the main
   PMIC in the system (perhaps over I2C)
3. If a machine needs access to the main PMIC in order to shutdown
   then it will never get it since the mutex was lost when the other
   CPU stopped.
4. We'll hang (possibly eventually hitting the hard lockup detector).

Let's avoid the problem by stopping the cpufreq governor at shutdown,
which is a sensible thing to do anyway.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

This platform_driver does not need to set an owner, it will be
populated by the driver core.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Pull ARM SoC fixes from Olof Johansson:
 "We've been sitting on our fixes branch for a while, so this batch is
  unfortunately on the large side.

  A lot of these are tweaks and fixes to device trees, fixing various
  bugs around clocks, reg ranges, etc.  There's also a few defconfig
  updates (which are on the late side, no more of those).

  All in all the diffstat is bigger than ideal at this time, but nothing
  in here seems particularly risky"

* tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (31 commits)
  reset: sunxi: fix spinlock initialization
  ARM: dts: disable CCI on exynos5420 based arndale-octa
  drivers: bus: check cci device tree node status
  ARM: rockchip: disable jtag/sdmmc autoswitching on rk3288
  ARM: nomadik: fix up leftover device tree pins
  ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree
  ARM: at91/dt: sam9263: Add missing clocks to lcdc node
  ARM: at91: sama5d3: dt: correct the sound route
  ARM: at91/dt: sama5d4: fix the timer reg length
  ARM: exynos_defconfig: Enable LM90 driver
  ARM: exynos_defconfig: Enable options for display panel support
  arm: dts: Use pmu_system_controller phandle for dp phy
  ARM: shmobile: sh73a0 legacy: Set .control_parent for all irqpin instances
  ARM: dts: berlin: correct BG2Q's SM GPIO location.
  ARM: dts: berlin: add broken-cd and set bus width for eMMC in Marvell DMP DT
  ARM: dts: berlin: fix io clk and add missing core clk for BG2Q sdhci2 host
  ARM: dts: Revert disabling of smc91x for n900
  ARM: dts: imx51-babbage: Fix ULPI PHY reset modelling
  ARM: dts: dra7-evm: fix qspi device tree partition size
  ARM: omap2plus_defconfig: use CONFIG_CPUFREQ_DT
  ...

Pull clock driver fixes from Mike Turquette:
 "Small number of fixes for clock drivers and a single null pointer
  dereference fix in the framework core code.

  The driver fixes vary from fixing section mismatch warnings to
  preventing machines from hanging (and preventing developers from
  crying)"

* tag 'clk-fixes-for-linus' of git://git.linaro.org/people/mike.turquette/linux:
  clk: fix possible null pointer dereference
  Revert "clk: ppc-corenet: Fix Section mismatch warning"
  clk: rockchip: fix deadlock possibility in cpuclk
  clk: berlin: bg2q: remove non-exist "smemc" gate clock
  clk: at91: keep slow clk enabled to prevent system hang
  clk: rockchip: fix rk3288 cpuclk core dividers
  clk: rockchip: fix rk3066 pll lock bit location
  clk: rockchip: Fix clock gate for rk3188 hclk_emem_peri
  clk: rockchip: add CLK_IGNORE_UNUSED flag to fix rk3066/rk3188 USB Host

Pull SCSI fixes from James Bottomley:
 "This is one fix for a Multiqueue sleeping in invalid context problem
  and a MAINTAINER file update for Qlogic"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ->queue_rq can't sleep
  MAINTAINERS: Update maintainer list for qla4xxx

The commit 646cafc6 (clk: Change clk_ops->determine_rate to
return a clk_hw as the best parent) opens a possibility for
null pointer dereference, fix this.
Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

This reverts commit da788acb.

That commit tried to fix the section mismatch warning by moving the
ppc_corenet_clk_driver struct to init section. This is definitely wrong
because the kernel would free the memories occupied by this struct
after boot while this driver is still registered in the driver core.
The kernel would panic when accessing this driver struct.

Cc: stable@vger.kernel.org # 3.17
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

Lockdep reported a possible deadlock between the cpuclk lock and for example
the i2c driver.

       CPU0                    CPU1
       ----                    ----
  lock(clk_lock);
                               local_irq_disable();
                               lock(&(&i2c->lock)->rlock);
                               lock(clk_lock);
  <Interrupt>
    lock(&(&i2c->lock)->rlock);

 *** DEADLOCK ***

The generic clock-types of the core ccf already use spin_lock_irqsave when
touching clock registers, so do the same for the cpuclk.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: removed initialization of "flags"]

Pull dmaengine fixes from Vinod Koul:
 "Two patches, the first by Andy to fix dw dmac runtime pm and second
  one by me to fix the dmaengine headers in MAINTAINERS"

* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: dw: balance PM runtime calls
  MAINTAINERS: dmaengine: fix the header file for dmaengine

Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also two PMU driver fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools powerpc: Use dwfl_report_elf() instead of offline.
  perf tools: Fix segfault for symbol annotation on TUI
  perf test: Fix dwarf unwind using libunwind.
  perf tools: Avoid build splat for syscall numbers with uclibc
  perf tools: Elide strlcpy warning with uclibc
  perf tools: Fix statfs.f_type data type mismatch build error with uclibc
  tools: Remove bitops/hweight usage of bits in tools/perf
  perf machine: Fix __machine__findnew_thread() error path
  perf tools: Fix building error in x86_64 when dwarf unwind is on
  perf probe: Propagate error code when write(2) failed
  perf/x86/intel: Fix bug for "cycles:p" and "cycles:pp" on SLM
  perf/rapl: Fix sysfs_show() initialization for RAPL PMU

Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

  - Fix segfault when using both the map symtab viewer and annotation
    in the TUI (Namhyung Kim).

  - uClibc build fixes (Alexey Brodkin, Vineet Gupta).

  - bitops/hweight were moved from tools/perf/ too tools/include, move
    some leftovers (Arnaldo Carvalho de Melo)

  - Fix dwarf unwind x86_64 build error (Namhyung Kim)

  - Fix __machine__findnew_thread() error path (Namhyung Kim)

  - Propagate error code when write(2) failed in 'perf probe' (Namhyung Kim)

  - Use dwfl_report_elf() instead of offline in powerpc bits to
    properly handle non prelinked DSOs (Sukadev Bhattiprolu).

  - Fix dwarf unwind using libunwind in 'perf test' (Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'samsung-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into fixes

Merge "Samsung fixes for v3.19" from Kukjin Kim:

Samsung fixes for v3.19
- exynos_defconfig: enable LM90 driver and display panel support
   - HWMON
   - SENSORS_LM90
   - Direct Rendering Manager (DRM)
   - DRM bridge registration and lookup framework
   - Parade ps8622/ps8625 eDP/LVDS bridge
   - NXP ptn3460 eDP/LVDS bridge
   - Exynos Fully Interactive Mobile Display controller (FIMD)
   - Panel registration and lookup framework
   - Simple panels
   - Backlight & LCD device support

- use pmu_system_controller phandle for dp phy
  : DP PHY requires pmu_system_controller to handle PMU reg. now

* tag 'samsung-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  ARM: exynos_defconfig: Enable LM90 driver
  ARM: exynos_defconfig: Enable options for display panel support
  arm: dts: Use pmu_system_controller phandle for dp phy
Signed-off-by: Olof Johansson <olof@lixom.net>

Call spin_lock_init() before the spinlocks are used, both in early init
and probe functions preventing a lockdep splat.

I have been observing lockdep complaining [1] during boot on my a80 optimus [2]
when CONFIG_PROVE_LOCKING has been enabled. This patch resolves the splat,
and has been tested on a few other sunxi platforms without issue.

[1] http://storage.kernelci.org/next/next-20150107/arm-multi_v7_defconfig+CONFIG_PROVE_LOCKING=y/lab-tbaker/boot-sun9i-a80-optimus.html
[2] http://kernelci.org/boot/?a80-optimusSigned-off-by: Tyler Baker <tyler.baker@linaro.org>
Cc: <stable@vger.kernel.org>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'renesas-soc-fixes-for-v3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas into fixes

Merge "Renesas ARM Based SoC Fixes for v3.19" from Simon Horman:

Renesas ARM Based SoC Fixes for v3.19

This pull request is based on the last round of SoC updates for v3.19,
Fourth Round of Renesas ARM Based SoC Updates for v3.19, tagged as
renesas-soc3-for-v3.19, merged into your next/soc branch and included in
v3.19-rc1.

- ARM: shmobile: r8a7740: Instantiate GIC from C board code in legacy builds

  Set .control_parent for all irqpin instances for sh73a0 SoC when booting
  using legacy C.

- ARM: shmobile: r8a7740: Instantiate GIC from C board code in legacy builds

  This fixes a long standing problem which has been present since
  the sh73a0 SoC started using the INTC External IRQ pin driver.

  The patch that introduced the problem is 341eb546 ("ARM:
  shmobile: INTC External IRQ pin driver on sh73a0") which was included
  in v3.10.

* tag 'renesas-soc-fixes-for-v3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
  ARM: shmobile: sh73a0 legacy: Set .control_parent for all irqpin instances
  ARM: shmobile: r8a7740: Instantiate GIC from C board code in legacy builds

The arndale-octa board was giving "imprecise external aborts" during
boot-up with MCPM enabled. CCI enablement of the boot cluster was found
to be the cause of these aborts (possibly because the secure f/w was not
allowing it). Hence, disable CCI for the arndale-octa board.
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Tyler Baker <tyler.baker@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

The arm-cci driver completes the probe sequence even if the cci node is
marked as disabled. Add a check in the driver to honour the cci status
in the device tree.
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'at91-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nferre/linux-at91 into fixes

Merge "at91: fixes for 3.19 #1 (ter)" from Nicolas Ferre:

First fixes batch for AT91 on 3.19:
- fix some DT entries
- correct clock entry for the at91sam9263 LCD
- add a phy_fixup for Eth1 on sama5d4

* tag 'at91-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nferre/linux-at91:
  ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree
  ARM: at91/dt: sam9263: Add missing clocks to lcdc node
  ARM: at91: sama5d3: dt: correct the sound route
  ARM: at91/dt: sama5d4: fix the timer reg length
Signed-off-by: Olof Johansson <olof@lixom.net>

rk3288 SoCs have a function to automatically switch between jtag/sdmmc pinmux
settings depending on the card state. This collides with a lot of assumptions.

It only works when using the internal card-detect mechanism and breaks
horribly when using either the normal card-detect via the slot-gpio function
or via any other pin. Also there is of course no link between the mmc and jtag
on the software-side, so the jtag clocks may very well be disabled when the
card is ejected and the soc switches back to the jtag pinmux.

Leaving the switching function enabled did result in mmc timeouts and rcu
stalls thus hanging the system on 3.19-rc1. Therefore disable it in all cases,
as we expect the devicetree to explicitly select either mmc or jtag pinmuxes
anyway.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'berlin-fixes-for-3.19-1' of git://git.infradead.org/users/hesselba/linux-berlin into fixes

Merge "ARM: berlin: Fixes for v3.19 (round 1)" from Sebastian Hesselbarth:

Marvell Berlin fixes for v3.19 round 1:
- SDHCI DT fixes for BG2Q and BG2Q reference board
- BG2Q SM GPIO DT node relocation

* tag 'berlin-fixes-for-3.19-1' of git://git.infradead.org/users/hesselba/linux-berlin:
  ARM: dts: berlin: correct BG2Q's SM GPIO location.
  ARM: dts: berlin: add broken-cd and set bus width for eMMC in Marvell DMP DT
  ARM: dts: berlin: fix io clk and add missing core clk for BG2Q sdhci2 host
Signed-off-by: Olof Johansson <olof@lixom.net>

We altered the device tree bindings for the Nomadik family of
pin controllers to be standard, this file was merged out-of-order
so we missed fixing this. Fix it up.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'omap-for-v3.19/fixes-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Merge "omap fixes against v3.19-rc1" from Tony Lindgren:

Fixes for omaps mostly to deal with dra7 timer issues
and hypervisor mode. The other fixes are minor fixes for
various boards. The summary of the fixes is:

- Fix real-time counter rate typos for some frequencies
- Fix counter frequency drift for am572x
- Fix booting of secondary CPU in HYP mode
- Fix n900 board name for legacy user space
- Fix cpufreq in omap2plus_defconfig after Kconfig change
- Fix dra7 qspi partitions

And also, let's re-enable smc91x on some n900 boards that
we have sitting in a few test boot systems after the boot
loader dependencies got fixed.

* tag 'omap-for-v3.19/fixes-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: dts: Revert disabling of smc91x for n900
  ARM: dts: dra7-evm: fix qspi device tree partition size
  ARM: omap2plus_defconfig: use CONFIG_CPUFREQ_DT
  ARM: OMAP2+: Fix n900 board name for legacy user space
  ARM: omap5/dra7xx: Enable booting secondary CPU in HYP mode
  ARM: dra7xx: Fix counter frequency drift for AM572x errata i856
  ARM: omap5/dra7xx: Fix frequency typos
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'imx-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into fixes

Merge "ARM: imx: fixes for 3.19" from Shawn Guo:

The i.MX fixes for 3.19:
 - One fix for incorrect i.MX25 SPI1 clock assignment in device tree,
   which causes system hang when accessing SPI1.
 - Correct i.MX6SX QSPI parent clock configuration to fix a kernel Oops.
 - Fix ULPI PHY reset modelling on imx51-babbage board to remove the
   dependency on bootloader for USB3317 ULPI PHY reset.
 - Correct video divider setting on i.MX6Q rev T0 1.0 to fix the issue
   that HDMI is not working at high resolution on T0 1.0.
 - One incremental fix for CODA960 VPU enabling in device tree to
   correct interrupt order.
 - LS1021A SCFG block works in BE mode, add device tree property
   big-endian to make it right.

* tag 'imx-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
  ARM: dts: imx51-babbage: Fix ULPI PHY reset modelling
  ARM: imx6sx: Set PLL2 as parent of QSPI clocks
  ARM: dts: imx25: Fix the SPI1 clocks
  ARM: clk-imx6q: fix video divider for rev T0 1.0
  ARM: dts: imx6qdl: Fix CODA960 interrupt order
  ARM: ls1021a: dtsi: add 'big-endian' property for scfg node
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'v3.19-rockchip-dtsfixes1' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip into fixes

Merge "ARM: rockchip: dts fix for 3.19" from Heiko Stübner:

Increase drive-strength to sdmmc pins on rk3288-evb to fix
an issue with the fixed highspeed card detection.

* tag 'v3.19-rockchip-dtsfixes1' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip:
  ARM: dts: rockchip: bump sd card pin drive strength up on rk3288-evb
Signed-off-by: Olof Johansson <olof@lixom.net>

Avoid overflow possibility.

[ The overflow is purely theoretical, since this is used for memory
  ranges that aren't even close to using the full 64 bits, but this is
  the right thing to do regardless.  - Linus ]
Signed-off-by: Louis Langholtz <lou_langholtz@me.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Peter Anvin <hpa@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dwfl_report_offline() works only when libraries are prelinked.

Replace dwfl_report_offline() with dwfl_report_elf() so we correctly
extract debug info even from libraries that are not prelinked.
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Link: http://lkml.kernel.org/r/20150114221045.GA17703@us.ibm.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Currently the symbol structure is allocated with symbol_conf.priv_size
to carry sideband information like annotation, map browser on TUI and
sort-by-name tree node.  So retrieving these information from symbol
needs to care about the details of such placement.

However the annotation code just assumes that the symbol is placed after
the struct annotation.  But actually there's other info between them.
So accessing those struct will lead to an undefined behavior (usually a
crash) after they write their info to the same location.

To reproduce the problem, please follow the steps below:

  1. run perf report (TUI of course) with -v option
  2. open map browser (by pressing right arrow key for any entry)
  3. search any function (by pressing '/' key and input whatever..)
  4. return to the hist browser (by pressing 'q' or left arrow key)
  5. open annotation window for the same entry (by pressing 'a' key)
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1421234288-22758-1-git-send-email-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Perf tool fails to unwind user stack if the event raises in a shared
object. This patch improves tests/dwarf-unwind.c to demonstrate the
problem by utilizing commonly used glibc function "bsearch". If perf is
not statically linked, the testcase will try to unwind a mixed call
trace.

By debugging libunwind I found that there is a bug in unwind-libunwind:
it always passes 0 as segbase to libunwind, cause libunwind unable to
locate debug_frame entry fir first level ip address (I add some more
debugging output into libunwind to make things clear):

               >_Uarm_dwarf_find_debug_frame: start_ip = 10be98, end_ip = 10c2a4
               >_Uarm_dwarf_find_debug_frame: found debug_frame table `/lib/libc-2.18.so': segbase=0x0, len=7, gp=0x0, table_data=0x449388
               >_Uarm_dwarf_search_unwind_table: call lookup:ip = b6cd3bcc, segbase = 0, rel_ip = b6cd3bcc
               >lookup: e->start_ip_offset = bcf18 (rel_ip = b6cd3bcc)
               >lookup: e->start_ip_offset = 6d314 (rel_ip = b6cd3bcc)
               >lookup: e->start_ip_offset = 33d0c (rel_ip = b6cd3bcc)
                ...
               >lookup: e->start_ip_offset = 15d0c (rel_ip = b6cd3bcc)
               >lookup: e->start_ip_offset = 15c40 (rel_ip = b6cd3bcc)
 >_Uarm_dwarf_search_unwind_table: IP b6cd3bcc inside range b6c12000-b6d4c000, but no explicit unwind info found
                >put_rs_cache: unmasking signals/interrupts and releasing lock
               >_Uarm_dwarf_step: returning -10
 >_Uarm_step: dwarf_step()=-10

This patch passes map->start as segbase to dwarf_find_debug_frame(), so
di will be initialized correctly.

In addition, dso and executable are different when setting segbase. This
patch first check whether the elf is executable, and pass segbase only
for shared object.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1421203007-75799-1-git-send-email-wangnan0@huawei.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>