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536,164 commits

Author SHA1 Message Date
Damien Lespiau
9043ae0205 drm/i915: Re-order the PCU opcodes
Let's keep that list sorted!

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:33 +02:00
Damien Lespiau
71cd8423cd drm/i915/skl: Fix the CTRL typo in the DPLL_CRTL1 defines
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:32 +02:00
Damien Lespiau
aeaa2122af drm/i915/skl: Add the INIT power domain to the MISC I/O power well
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:31 +02:00
Michel Thierry
4dd738e9cd drm/i915: Fix 32b overflow check in gen8_ppgtt_alloc_page_directories
The patch 69876bed7e: "drm/i915/gen8:
page directories rework allocation" added an overflow warning, but the
mask had an extra 0. Use less typo-prone option suggested by Dave
instead, to check for (start + length) >= 0x100000000ULL.

This check will be unnecessary after gen8_alloc_va_range handles more
than 4 PDPs (48b addressing).

v2: Really check for 32b overflow (Ville)

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dave Gordon <david.s.gordon@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:30 +02:00
Mika Kuoppala
5e562f1ddd drm/i915: Clear vma->bound on unbinding
Unbinding doesn't always lead to unconditional destruction
of vma. This destruction avoidance happens if vma is part of
execbuffer relocation list or if vma is being considered for
eviction in i915_gem_evict_something().

For those other users, mark the vma unbound so that
the correct state of this vma is preserved.

Reported-by: Chris Wilson <chris@chris-wilson.co.ok>
Cc: Chris Wilson <chris@chris-wilson.co.ok>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:29 +02:00
Jani Nikula
65b38e0d87 drm/i915: make drm_crtc_helper_funcs const data
Because they can be.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:28 +02:00
Mika Kahola
5fa836a9d8 drm/i915: DP link training optimization
This patch adds DP link training optimization by reusing the
previously trained values.

v2:
- rebase

V3:
- rebase

V4:
- when HPD long pulse is received, the flag is cleared
  that indicates if DP link training is required or not
  (based on Sivakumar's comment)

Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:27 +02:00
Mika Kahola
4e96c97742 drm/i915: eDP link training optimization
This is a first of series patches that optimize DP link
training. The first patch is for eDP only where we reuse
the previously trained link training values from cache
i.e. voltage swing and pre-emphasis levels.

In case we are not able to train the link by reusing
the known values, the link training parameters are set
to zero and training is restarted.

V2:
- flag that indicates if DP link is trained and valid
  renamed from 'link_trained' to 'train_set_valid'
- removed routine 'intel_dp_reuse_link_train'

V3:
- rebased against the latest drm-intel-nightly

V4:
- removed HPD long pulse handling for eDP case to clear the
  flag that indicates to reuse the current link training
  parameters. (based on Sivakumar's comment)

Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
[danvet: s/DP/eDP/ in subject to make scope clear.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:26 +02:00
Deepak S
3ef62342bd drm/i915: Setup static bias for GPU
Based on the spec, Setting up static BIAS for GPU to improve the
rps performace.

v2: rename reg defn to match spec. (Ville)

v3: Updated bias setting for chv (Deepak)

Signed-off-by: Deepak S <deepak.s@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:25 +02:00
Dan Carpenter
3126a660f3 drm/i915: checking IS_ERR() instead of NULL
We switched from calling i915_gem_alloc_context_obj() to calling
i915_gem_alloc_object() so the error handling needs to be updated to
check for NULL instead of IS_ERR().

Fixes: 149c86e74f ('drm/i915: Allocate context objects from stolen')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:23 +02:00
Chris Wilson
d4dc5e92c0 drm/i915: Remove incorrect restriction on 32bit offsets in ppGTT backend
This is the wrong layer to apply an arbitrary restriction and the wrong
error code (object too large!). If we do want to prevent large offsets
being return to the user on 32bit systems (to hide bugs in userspace),
you want to restrict the drm_mm range manager instead. This first tells
userspace about the correct size of the GTT they can use (so they don't
try and overallocate object or batches), and fixes the eviction logic to
avoid the eventual and *guaranteed* error.

Fixes regression in
commit d7b2633dba
Author: Michel Thierry <michel.thierry@intel.com>
Date:   Wed Apr 8 12:13:34 2015 +0100

    drm/i915/gen8: Dynamic page table allocations

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:22 +02:00
Chris Wilson
d86ed34a4e drm/i915: Add RPS thresholds to debugfs/i915_frequency_info
Expose some more of our internal RPS bookkeeping for debugging.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:21 +02:00
Fabian Frederick
0b6cc18810 drm/i915: use ERR_CAST instead of ERR_PTR/PTR_ERR
Inspired by scripts/coccinelle/api/err_cast.cocci

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:20 +02:00
Joonas Lahtinen
06615ee5c5 drm/i915: Do not clear mappings beyond VMA size
Do not to clear mappings outside the allocated VMA under any
circumstances. Only clear the smaller of VMA or object page count.

This is required to allow creating partial object VMAs which in
turn are needed for partial GGTT views.

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:19 +02:00
Todd Previte
09b1eb130e drm/i915: Move Displayport test request and sink IRQ logic to intel_dp_detect()
Due to changes in the driver and to support Displayport compliance testing,
the test request and sink IRQ logic has been relocated from
intel_dp_check_link_status to intel_dp_detect. This is because the bulk of the
compliance tests that set the TEST_REQUEST bit in the DEVICE_IRQ field of the
DPCD issue a long pulse / hot plug event to signify the start of the test.
Currently, for a long pulse, intel_dp_check_link_status is not called for a
long HPD pulse, so if test requests come in, they cannot be detected by the
driver.

Once located in the intel_dp_detect, in the regular hot plug event path,
proper detection of Displayport compliance test requests occurs which then
invokes the test handler to support them. Additionally, this places compliance
testing in the normal operational paths, eliminating as much special case code
as possible.

The only change in intel_dp_check_link_status with this patch is that when
the IRQ is the result of a test request from the sink, the test handler is not
invoked during the short pulse path. Short pulse test requests are for a
particular variety of tests (mainly link training) that will be implemented
in the future. Once those tests are available, the test request handler will
be called from here as well.

V2:
- Rewored the commit message to be more clear about the content and intent
  of this patch
- Restore IRQ detection logic to intel_dp_check_link_status(). Continue to
  detect and clear sink IRQs in the short pulse case. Ignore test requests
  in the short pulses for now since they are for future test implementations.

Signed-off-by: Todd Previte <tprevite@gmail.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:18 +02:00
Suketu Shah
00776511da drm/i915/skl: Enable runtime PM
Enable runtime PM for Skylake platform

v2: After adding dmc ver 1.0 support rebased on top of nightly. (Animesh)

Issue: VIZ-2819
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Suketu Shah <suketu.j.shah@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:17 +02:00
Suketu Shah
93c7cb6c3a drm/i915/skl: Assert the requirements to enter or exit DC6.
Warn if the conditions to enter or exit DC6 are not satisfied such
as support for runtime PM, state of power well, CSR loading etc.

v2: Removed camelcase in functions and variables.

v3: Do some minimal check to assert if CSR program is not loaded.

v4:
1] Correct the check for backlight-disabling in assert_can_enable_dc6().
2] Check csr.loaded = false before disabling DC6 and simplify other checks.

v5:
1] Remove checks for DC5 state from assert_can_enable_dc6 function as DC5 is no
   longer enabled before enabling DC6.
2] Correct the check for CSR-loading in assert_can_disable_dc6 function as CSR must
   be loaded for context restore to happen on DC6 disabling.

v6:
1] It's okay to explicitly disable DC6 during driver-load/resume even though it might
   already be disabled and so don't warn about it.

v7: Rebase to latest.

v8: Sqashed the patch from Imre -
[PATCH] drm/i915/skl: avoid false CSR fw not loaded WARN during driver load/resume

v9: After adding dmc ver 1.0 support rebased on top of nightly. (Animesh)

v10: During initialization added a early return before disabling DC5. (Animesh)

Issue: VIZ-2819
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Suketu Shah <suketu.j.shah@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:16 +02:00
A.Sunil Kamath
74b4f371f5 Implement enable/disable for Display C6 state
This patch just implements the basic enable and disable
functions of DC6 state which is needed for SKL platform.

Its important to load SKL CSR program before calling enable.

DC6 is a deeper power saving state where hardware dynamically
disables power well 0 and saves the associated registers.
DC6 can be entered when software allows it, the conditions
for DC5 are met, and the PCU allows DC6.
DC6 cannot be used if the backlight is being driven from the
display utility pin.

Its better to configure display engine to have power well 2
disabled before getting into DC6 enable function. Hence rpm
framework will ensure to check status of power well 2 and DC5
before calling skl_enable_dc6.

v2: Replace HAS_ with IS_ check as per Daniel's review comments

v3: Cleared the bits dc5/dc6 enable of DC_STATE_EN register
before setting them as per Satheesh's review comments.

v4: No need to call gen9_disable_dc5 inside enable sequence of
DC6, as its already take care above.

v5: call POSTING_READ for every write to a register to ensure that
its written immediately.
Call intel_prepare_ddi during DC6 exit as it's required on low-power exit.

v6: Protect DC6-enabling-disabling functionality with locks to synchronize
with CSR-loading code.

v7: Remove grabbing CSR-related mutex in skl_enable/disable_dc6 functions as
    deferred DC5-enabling functionality is now removed.

v8: Remove 'Disabling DC5' from the debug comment during DC6 enabling as when
    DC6 is allowed, DC5 is not programmed at all.

v9:
- Rebase to latest.
- Move all DC6-related functions from intel_display.c to intel_runtime_pm.c.

v10: After adding dmc ver 1.0 support rebased on top of nightly. (Animesh)

Issue: VIZ-2819
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:15 +02:00
Suketu Shah
f75a198513 drm/i915/skl: Add DC6 Trigger sequence.
Add triggers for DC6 as per details provided in skl_enable_dc6
and skl_disable_dc6 implementations.

Also Call POSTING_READ for every write to a register to ensure
it is written to immediately

v1: Remove POSTING_READ and intel_prepare_ddi calls as they've been added in previous patches.

v2:
1] Remove check for backlight disabled as it should be the case by that time.
2] Mark DC5 as disabled when enabling DC6.
3] Return from DC5-disabling function early if DC5 is already be disabled which can happen
   due to DC6-enabling earlier.
3] Ensure CSR firmware is loaded after resume from DC6 as corresponding memory contents won't
   be retained after runtime-suspend.
4] Ensure that CSR isn't identified as loaded before CSR-loading program is called during
   runtime-resume.

v3: Rebase to latest
Modified as per review comments from Imre and after discussion with Art:
1] DC6 should be preferably enabled when PG2 is disabled by SW as the check for PG1 being
   disabled is taken of by HW to enter DC6, and disabled when PG2 is enabled respectively.
   This helps save more power, especially in the case when display is disabled but GT is
   enabled. Accordingly, replacing DC5 trigger sequence with DC6 for SKL.
2] DC6 could be enabled from intel_runtime_suspend() function, if DC5 is already enabled.
3] Move CSR-load-status setting code from intel_runtime_suspend function to a new function.

v4:
1] Enable/disable DC6 only when toggling the power-well using a newly defined macro ENABLE_DC6.

v5:
1] Load CSR on system resume too as firmware may be lost on system suspend preventing
   enabling DC5, DC6.
2] DDI buffers shouldn't be programmed during driver-load/resume as it's already done
   during modeset initialization then and also that the encoder list is still uninitialized by
   then. Therefore, call intel_prepare_ddi function right after disabling DC6 but outside
   skl_disable_dc6 function and not during driver-load/resume.

v6:
1] Rebase to latest.
2] Move SKL_ENABLE_DC6 macro definition from intel_display.c to intel_runtime_pm.c.

v7:
1) Refactored the code for removing the warning got from checkpatch.
2) After adding dmc ver 1.0 support rebased on top of nightly. (Animesh)

v8:
- Reverted the changes done in v7.
- Removed the condition check in skl_prepare_resune(). (Animesh)

Issue: VIZ-2819
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Suketu Shah <suketu.j.shah@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:14 +02:00
Suketu Shah
5aefb2398a drm/i915/skl: Assert the requirements to enter or exit DC5.
Warn if the conditions to enter or exit DC5 are not satisfied such
as support for runtime PM, state of power well, CSR loading etc.

v2: Removed camelcase in functions and variables.

v3: Do some minimal check to assert if CSR program is not loaded.

v4:
1] Used an appropriate function lookup_power_well() to identify power well,
instead of using a magic number which can change in future.
2] Split the conditions further in assert_can_enable_DC5() and added more checks.
3] Removed all WARNs from assert_can_disable_DC5 as they were unnecessary and added two
   new ones.
4] Changed variable names as updated in earlier patches.

v5:
1] Change lookup_power_well function to take an int power well id.
2] Define a new intel_display_power_well_is_enabled helper function to check whether a
   particular power well is enabled.
3] Use CSR-related mutex in assert_csr_loaded function.

v6: Remove use of dc5_enabled variable as it's no longer needed.

v7:
1] Rebase to latest.
2] Move all DC5-related functions from intel_display.c to intel_runtime_pm.c.

v8: After adding dmc ver 1.0 support rebased on top of nightly. (Animesh)

v9: Modified below changes based on review comments from Imre.
- Moved intel_display_power_well_is_enabled() to intel_runtime_pm.c.
- Removed mutex lock from assert_csr_loaded(). (Animesh)

Issue: VIZ-2819
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Suketu Shah <suketu.j.shah@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:13 +02:00
A.Sunil Kamath
6b457d31ea drm/i915/skl: Implement enable/disable for Display C5 state.
This patch just implements the basic enable and disable
functions of DC5 state which is needed for both SKL and BXT.

Its important to load respective CSR program before calling
enable, which anyways will happen as CSR program is executed
during boot.

DC5 is a power saving state where hardware dynamically disables
power well 1 and the CDCLK PLL and saves the associated registers.

DC5 can be entered when software allows it, power well 2 is
disabled, and hardware detects that all pipes are disabled
or pipe A is enabled with PSR active.

Its better to configure display engine to have power well 2 disabled before
getting into DC5 enable function. Hence rpm framework will have to
ensure to check status of power well 2 before calling gen9_enable_dc5.

Rather dc5 entry criteria should be decided based on power well 2 status.
If disabled, then call gen9_enable_dc5.

v2: Replace HAS_ with IS_ check as per Daniel's review comments

v3: Cleared the bits dc5/dc6 enable of DC_STATE_EN register
before setting them as per Satheesh's review comments.

v4: call POSTING_READ for every write to a register to ensure that
its written immediately.

v5: Modified as per review comments from Imre.
- Squashed register definitions into this patch.
- Finetuned comments and functions.

v6:
Avoid redundant writes in gen9_set_dc_state_debugmask_memory_up function.

v7:
- Rebase to latest.
- Move all runtime PM functions defined in intel_display.c to
  intel_runtime_pm.c.

v8: Rebased to drm-intel-nightly. (Animesh)

Issue: VIZ-2819
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:12 +02:00
Suketu Shah
dc17430054 drm/i915/skl: Add DC5 Trigger Sequence
Add triggers as per expectations mentioned in gen9_enable_dc5
and gen9_disable_dc5 patch.

Also call POSTING_READ for every write to a register to ensure that
its written immediately.

v1: Remove POSTING_READ calls as they've already been added in previous patches.

v2: Rebase to move all runtime pm specific changes to intel_runtime_pm.c file.

Modified as per review comments from Imre:
1] Change variable name 'dc5_allowed' to 'dc5_enabled' to correspond to relevant
   functions.
2] Move the check dc5_enabled in skl_set_power_well() to disable DC5 into
   gen9_disable_DC5 which is a more appropriate place.
3] Convert checks for 'pm.dc5_enabled' and 'pm.suspended' in skl_set_power_well()
   to warnings. However, removing them for now as they'll be included in a future patch
   asserting DC-state entry/exit criteria.
4] Enable DC5, only when CSR firmware is verified to be loaded. Create new structure
   to track 'enabled' and 'deferred' status of DC5.
5] Ensure runtime PM reference is obtained, if CSR is not loaded, to avoid entering
   runtime-suspend and release it when it's loaded.
6] Protect necessary CSR-related code with locks.
7] Move CSR-loading call to runtime PM initialization, as power domains needed to be
   accessed during deferred DC5-enabling, are not initialized earlier.

v3: Rebase to latest.

Modified as per review comments from Imre:
1] Use blocking wait for CSR-loading to finish to enable DC5  for simplicity, instead of
   deferring enabling DC5 until CSR is loaded.
2] Obtain runtime PM reference during CSR-loading initialization itself as deferred DC5-
   enabling is removed and release it at the end of CSR-loading functionality.
3] Revert calling CSR-loading functionality to the beginning of i915 driver-load
   functionality to avoid any delay in loading.
4] Define another variable to track whether CSR-loading failed and use it to avoid enabling
   DC5 if it's true.
5] Define CSR-load-status accessor functions for use later.

v4:
1] Disable DC5 before enabling PG2 instead of after it.
2] DC5 was being mistaken enabled even when CSR-loading timed-out. Fix that.
3] Enable DC5-related functionality using a macro.
4] Remove dc5_enabled tracking variable and its use as it's not needed now.

v5:
1] Mark CSR failed to load where necessary in finish_csr_load function.
2] Use mutex-protected accessor function to check if CSR loaded instead of directly
   accessing the variable.
3] Prefix csr_load_status_get/set function names with intel_.

v6: rebase to latest.
v7: Rebase on top of nightly (Damien)
v8: Squashed the patch from Imre - added csr helper pointers to simplify the code. (Imre)
v9: After adding dmc ver 1.0 support rebased on top of nightly. (Animesh)
v10: Added a enum for different csr states, suggested by Imre. (Animesh)

v11: Based on review comments from Imre, Damien and Daniel following changes done
- enum name chnaged to csr_state (singular form).
- FW_UNINITIALIZED used as zeroth element in enum csr_state.
- Prototype changed for helper function(set/get csr status), using enum csr_state instead of bool.

v12: Based on review comment from Imre, introduced bool fw_loaded local to finish_csr_load() which helps
calling once to set the csr status. The same flag used to fail RPM if find any issue during
firmware loading.

Issue: VIZ-2819
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Suketu Shah <suketu.j.shah@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:11 +02:00
Daniel Vetter
eb805623d8 drm/i915/skl: Add support to load SKL CSR firmware.
Display Context Save and Restore support is needed for
various SKL Display C states like DC5, DC6.

This implementation is added based on first version of DMC CSR program
that we received from h/w team.

Here we are using request_firmware based design.
Finally this firmware should end up in linux-firmware tree.

For SKL platform its mandatory to ensure that we load this
csr program before enabling DC states like DC5/DC6.

As CSR program gets reset on various conditions, we should ensure
to load it during boot and in future change to be added to load
this system resume sequence too.

v1: Initial relese as RFC patch

v2: Design change as per Daniel, Damien and Shobit's review comments
request firmware method followed.

v3: Some optimization and functional changes.
Pulled register defines into drivers/gpu/drm/i915/i915_reg.h
Used kmemdup to allocate and duplicate firmware content.
Ensured to free allocated buffer.

v4: Modified as per review comments from Satheesh and Daniel
Removed temporary buffer.
Optimized number of writes by replacing I915_WRITE with I915_WRITE64.

v5:
Modified as per review comemnts from Damien.
- Changed name for functions and firmware.
- Introduced HAS_CSR.
- Reverted back previous change and used csr_buf with u8 size.
- Using cpu_to_be64 for endianness change.

Modified as per review comments from Imre.
- Modified registers and macro names to be a bit closer to bspec terminology
and the existing register naming in the driver.
- Early return for non SKL platforms in intel_load_csr_program function.
- Added locking around CSR program load function as it may be called
concurrently during system/runtime resume.
- Releasing the fw before loading the program for consistency
- Handled error path during f/w load.

v6: Modified as per review comments from Imre.
- Corrected out_freecsr sequence.

v7: Modified as per review comments from Imre.
Fail loading fw if fw->size%8!=0.

v8: Rebase to latest.

v9: Rebase on top of -nightly (Damien)

v10: Enabled support for dmc firmware ver 1.0.
According to ver 1.0 in a single binary package all the firmware's that are
required for different stepping's of the product will be stored. The package
contains the css header, followed by the package header and the actual dmc
firmwares. Package header contains the firmware/stepping mapping table and
the corresponding firmware offsets to the individual binaries, within the
package. Each individual program binary contains the header and the payload
sections whose size is specified in the header section. This changes are done
to extract the specific firmaware from the package. (Animesh)

v11: Modified as per review comemnts from Imre.
- Added code comment from bpec for header structure elements.
- Added __packed to avoid structure padding.
- Added helper functions for stepping and substepping info.
- Added code comment for CSR_MAX_FW_SIZE.
- Disabled BXT firmware loading, will be enabled with dmc 1.0 support.
- Changed skl_stepping_info based on bspec, earlier used from config DB.
- Removed duplicate call of cpu_to_be* from intel_csr_load_program function.
- Used cpu_to_be32 instead of cpu_to_be64 as firmware binary in dword aligned.
- Added sanity check for header length.
- Added sanity check for mmio address got from firmware binary.
- kmalloc done separately for dmc header and dmc firmware. (Animesh)

v12: Modified as per review comemnts from Imre.
- Corrected the typo error in skl stepping info structure.
- Added out-of-bound access for skl_stepping_info.
- Sanity check for mmio address modified.
- Sanity check added for stepping and substeppig.
- Modified the intel_dmc_info structure, cache only the required header info. (Animesh)

v13: clarify firmware load error message.
The reason for a firmware loading failure can be obscure if the driver
is built-in. Provide an explanation to the user about the likely reason for
the failure and how to resolve it. (Imre)

v14: Suggested by Jani.
- fix s/I915/CONFIG_DRM_I915/ typo
- add fw_path to the firmware object instead of using a static ptr (Jani)

v15:
1) Changed the firmware name as dmc_gen9.bin, everytime for a new firmware version a symbolic link
with same name will help not to build kernel again.
2) Changes done as per review comments from Imre.
- Error check removed for intel_csr_ucode_init.
- Moved csr-specific data structure to intel_csr.h and optimization done on structure definition.
- fw->data used directly for parsing the header info & memory allocation
only done separately for payload. (Animesh)

v16:
- No need for out_regs label in i915_driver_load(), so removed it.
- Changed the firmware name as skl_dmc_ver1.bin, followed naming convention <platform>_dmc_<api-version>.bin (Animesh)

Issue: VIZ-2569
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:10 +02:00
Daniel Vetter
c6b8a4bc1e drm/i915: Simplify cmd-parser DISPATCH_SECURE check
i915_needs_cmd_parser already checks that for us.

Suggested-by: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2015-05-08 13:03:09 +02:00
Nick Hoath
dfb601e6d2 drm/i915/bxt: Add WaDisableThreadStallDopClockGating
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:08 +02:00
Chandra Konduru
c331879ce8 drm/i915: skylake sprite plane scaling using shared scalers
This patch enables skylake sprite plane display scaling using shared
scalers atomic desgin.

v2:
-use single copy of scaler limits (Matt)

v3:
-detaching scalers moved to crtc commit path (Matt)

v4:
-changes to align with updated scaler structures (Matt, me)
-keep sprite src rect in 16.16 format (Matt, Daniel)

v5:
-rebased on top of 90/270 rotation changes (me)
-Refactored skl_update_plane to reduce its size (Daniel)
 It is a step towards having a single function covering all planes.

Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Testcase: igt/kms_plane_scaling
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:07 +02:00
Chandra Konduru
6156a45602 drm/i915: skylake primary plane scaling using shared scalers
This patch enables skylake primary plane scaling using shared
scalers atomic desgin.

v2:
-use single copy of scaler limits (Matt)

v3:
-move detach_scalers to crtc commit path (Matt)
-use values in plane_state->src as regular integers (me)

v4:
-changes to align with updated scaler structures (Matt, me)
-keep plane src rect in 16.16 format (Matt, Daniel)

v5:
-Rebased on top of 90/270 rotation changes (me)
-Fixed an issue introduced by 90/270 changes where plane programming
 is using drm_plane->state rect instead of intel_plane->state rect.
 This change also required for scaling to work properly. (me)
-With 90/270, updated limits to cover both portrait and landscape usages (me)
-Refactored skylake_update_primary_plane to reduce its size (Daniel)
 Added helper functions for refactoring are comprehended enough to be
 used for skylake_update_plane (for sprite) too. One stop towards
 having single function for all planes.

v6:
-Added fixme note when checking plane_state->src width in update_plane (Daniel)
-Release lock when failing to colorkey request with active scaler (Daniel)

Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
Reviewed-by: matthew.d.roper@intel.com
Reviewed-by: sonika.jindal@intel.com (v5)
Testcase: igt/kms_plane_scaling
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-05-08 13:03:06 +02:00
Kirill A. Shutemov
cad14bb9f8 x86/kconfig: Fix the CONFIG_NR_CPUS description
Since:

  b53b5eda81 ("x86/cpu: Increase max CPU count to 8192")

... the maximum supported NR_CPUS for CPUMASK_OFFSTACK case
is 8192. Let's adjust the description to reflect the change.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431080726-2490-1-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:58:56 +02:00
Kirill A. Shutemov
c5c19941ad x86/kconfig: Bump default NR_CPUS from 8 to 64 for 64-bit configuration
Default NR_CPUS==8 is not enough to cover high-end desktop
configuration: Haswell-E has upto 16 threads.

Let's increase default NR_CPUS to 64 on 64-bit configuration.
With this value CPU bitmask will still fit into one unsigned long.

Default for 32-bit configuration is still 8: it's unlikely
anybody will run 32-bit kernels on modern hardware.

As an alternative we could bump NR_CPUS to 128 to cover all
dual-processor servers with some margin.

For reference: Debian and Suse build their kernels with
NR_CPUS==512, Fedora -- 1024.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431080745-19792-1-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:58:56 +02:00
Mario Kleiner
3790e395b8 drm/tegra: Don't use vblank_disable_immediate on incapable driver.
Tegra would not only need a hardware vblank counter that
increments at leading edge of vblank, but also support
for instantaneous high precision vblank timestamp queries, ie.
a proper implementation of dev->driver->get_vblank_timestamp().

Without these, there can be off-by-one errors during vblank
disable/enable if the scanout is inside vblank at en/disable
time, and additionally clients will never see any useable
vblank timestamps when querying via drmWaitVblank ioctl. This
would negatively affect swap scheduling under X11 and Wayland.

Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-05-08 20:56:34 +10:00
Denys Vlasenko
2a4e90b18c x86: Force inlining of atomic ops
With both gcc 4.7.2 and 4.9.2, sometimes gcc mysteriously
doesn't inline very small functions we expect to be inlined:

$ nm --size-sort vmlinux | grep -iF ' t ' | uniq -c | grep -v '^
*1 ' | sort -rn     473 000000000000000b t spin_unlock_irqrestore
    449 000000000000005f t rcu_read_unlock
    355 0000000000000009 t atomic_inc                <== THIS
    353 000000000000006e t rcu_read_lock
    350 0000000000000075 t rcu_read_lock_sched_held
    291 000000000000000b t spin_unlock
    266 0000000000000019 t arch_local_irq_restore
    215 000000000000000b t spin_lock
    180 0000000000000011 t kzalloc
    165 0000000000000012 t list_add_tail
    161 0000000000000019 t arch_local_save_flags
    153 0000000000000016 t test_and_set_bit
    134 000000000000000b t spin_unlock_irq
    134 0000000000000009 t atomic_dec                <== THIS
    130 000000000000000b t spin_unlock_bh
    122 0000000000000010 t brelse
    120 0000000000000016 t test_and_clear_bit
    120 000000000000000b t spin_lock_irq
    119 000000000000001e t get_dma_ops
    117 0000000000000053 t cpumask_next
    116 0000000000000036 t kref_get
    114 000000000000001a t schedule_work
    106 000000000000000b t spin_lock_bh
    103 0000000000000019 t arch_local_irq_disable
...

Note sizes of marked functions. They are merely 9 bytes long!
Selecting function with 'atomic' in their names:

    355 0000000000000009 t atomic_inc
    134 0000000000000009 t atomic_dec
     98 0000000000000014 t atomic_dec_and_test
     31 000000000000000e t atomic_add_return
     27 000000000000000a t atomic64_inc
     26 000000000000002f t kmap_atomic
     24 0000000000000009 t atomic_add
     12 0000000000000009 t atomic_sub
     10 0000000000000021 t __atomic_add_unless
     10 000000000000000a t atomic64_add
      5 000000000000001f t __atomic_add_unless.constprop.7
      5 000000000000000a t atomic64_dec
      4 000000000000001f t __atomic_add_unless.constprop.18
      4 000000000000001f t __atomic_add_unless.constprop.12
      4 000000000000001f t __atomic_add_unless.constprop.10
      3 000000000000001f t __atomic_add_unless.constprop.13
      3 0000000000000011 t atomic64_add_return
      2 000000000000001f t __atomic_add_unless.constprop.9
      2 000000000000001f t __atomic_add_unless.constprop.8
      2 000000000000001f t __atomic_add_unless.constprop.6
      2 000000000000001f t __atomic_add_unless.constprop.5
      2 000000000000001f t __atomic_add_unless.constprop.3
      2 000000000000001f t __atomic_add_unless.constprop.22
      2 000000000000001f t __atomic_add_unless.constprop.14
      2 000000000000001f t __atomic_add_unless.constprop.11
      2 000000000000001e t atomic_dec_if_positive
      2 0000000000000014 t atomic_inc_and_test
      2 0000000000000011 t atomic_add_return.constprop.4
      2 0000000000000011 t atomic_add_return.constprop.17
      2 0000000000000011 t atomic_add_return.constprop.16
      2 000000000000000d t atomic_inc.constprop.4
      2 000000000000000c t atomic_cmpxchg

This patch fixes this for x86 atomic ops via
s/inline/__always_inline/. This decreases allyesconfig kernel by
about 25k:

    text     data      bss       dec     hex filename
82399481 22255416 20627456 125282353 777a831 vmlinux.before
82375570 22255544 20627456 125258570 7774b4a vmlinux

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1431080762-17797-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:55:50 +02:00
Dave Airlie
94754c183a Merge tag 'drm-amdkfd-fixes-2015-05-07' of git://people.freedesktop.org/~gabbayo/linux into drm-fixes
- Add missing initialization of SDMA vm register when creating an SDMA queue
- Don't report local memory size, as we don't support local memory allocation
  yet.
- Allow to unregister process with exisiting queues. Until now we blocked
  it with BUG_ON, which was also an error by itself.

* tag 'drm-amdkfd-fixes-2015-05-07' of git://people.freedesktop.org/~gabbayo/linux:
  drm/amdkfd: Initialize sdma vm when creating sdma queue
  drm/amdkfd: Don't report local memory size
  drm/amdkfd: allow unregister process with queues
2015-05-08 20:52:51 +10:00
Dave Airlie
7122e505a5 Merge branch 'drm-fixes-4.1' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
Mostly stability fixes for UVD and VCE, plus a few other bug and regression
fixes.

* 'drm-fixes-4.1' of git://people.freedesktop.org/~agd5f/linux:
  drm/radeon: stop trying to suspend UVD sessions
  drm/radeon: more strictly validate the UVD codec
  drm/radeon: make UVD handle checking more strict
  drm/radeon: make VCE handle check more strict
  drm/radeon: fix userptr lockup
  drm/radeon: fix userptr BO unpin bug v3
  drm/radeon: don't setup audio on asics that don't support it
  drm/radeon: disable semaphores for UVD V1 (v2)
2015-05-08 20:52:21 +10:00
Dave Airlie
e1dee1973c Merge tag 'drm-intel-next-2015-04-23-fixed' of git://anongit.freedesktop.org/drm-intel into drm-next
drm-intel-next-2015-04-23:
- dither support for ns2501 dvo (Thomas Richter)
- some polish for the gtt code and fixes to finally enable the cmd parser on hsw
- first pile of bxt stage 1 enabling (too many different people to list ...)
- more psr fixes from Rodrigo
- skl rotation support from Chandra
- more atomic work from Ander and Matt
- pile of cleanups and micro-ops for execlist from Chris
drm-intel-next-2015-04-10:
- cdclk handling cleanup and fixes from Ville
- more prep patches for olr removal from John Harrison
- gmbus pin naming rework from Jani (prep for bxt)
- remove ->new_config from Ander (more atomic conversion work)
- rps (boost) tuning and unification with byt/bsw from Chris
- cmd parser batch bool tuning from Chris
- gen8 dynamic pte allocation (Michel Thierry, based on work from Ben Widawsky)
- execlist tuning (not yet all of it) from Chris
- add drm_plane_from_index (Chandra)
- various small things all over

* tag 'drm-intel-next-2015-04-23-fixed' of git://anongit.freedesktop.org/drm-intel: (204 commits)
  drm/i915/gtt: Allocate va range only if vma is not bound
  drm/i915: Enable cmd parser to do secure batch promotion for aliasing ppgtt
  drm/i915: fix intel_prepare_ddi
  drm/i915: factor out ddi_get_encoder_port
  drm/i915/hdmi: check port in ibx_infoframe_enabled
  drm/i915/hdmi: fix vlv infoframe port check
  drm/i915: Silence compiler warning in dvo
  drm/i915: Update DRIVER_DATE to 20150423
  drm/i915: Enable dithering on NatSemi DVO2501 for Fujitsu S6010
  rm/i915: Move i915_get_ggtt_vma_pages into ggtt_bind_vma
  drm/i915: Don't try to outsmart gcc in i915_gem_gtt.c
  drm/i915: Unduplicate i915_ggtt_unbind/bind_vma
  drm/i915: Move ppgtt_bind/unbind around
  drm/i915: move i915_gem_restore_gtt_mappings around
  drm/i915: Fix up the vma aliasing ppgtt binding
  drm/i915: Remove misleading comment around bind_to_vm
  drm/i915: Don't use atomics for pg_dirty_rings
  drm/i915: Don't look at pg_dirty_rings for aliasing ppgtt
  drm/i915/skl: Support Y tiling in MMIO flips
  drm/i915: Fixup kerneldoc for struct intel_context
  ...

Conflicts:
	drivers/gpu/drm/i915/i915_drv.c
2015-05-08 20:51:06 +10:00
Ingo Molnar
562bfca4c8 x86/mm: Clean up types in xlate_dev_mem_ptr() some more
So Linus noticed that in:

  94d4b4765b ("x86/mm: Clean up types in xlate_dev_mem_ptr()")

... I added two nonsensical casts, due to the poor type choice
for 'vaddr'.

Change it to 'void *' and take advantage of void * arithmetics.

This removes the casts.

( Also remove a nonsensical return line from unxlate_dev_mem_ptr()
  while at it. )

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:43:53 +02:00
Ingo Molnar
99e711101c Merge branch 'linus' into x86/cleanups, before applying dependent patch 2015-05-08 12:41:09 +02:00
David Vrabel
e95e6f176c locking/pvqspinlock, x86: Enable PV qspinlock for Xen
This patch adds the necessary Xen specific code to allow Xen to
support the CPU halting and kicking operations needed by the queue
spinlock PV code.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-12-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:37:18 +02:00
Waiman Long
bf0c7c34ad locking/pvqspinlock, x86: Enable PV qspinlock for KVM
This patch adds the necessary KVM specific code to allow KVM to
support the CPU halting and kicking operations needed by the queue
spinlock PV code.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-11-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:37:17 +02:00
Peter Zijlstra (Intel)
f233f7f158 locking/pvqspinlock, x86: Implement the paravirt qspinlock call patching
We use the regular paravirt call patching to switch between:

  native_queued_spin_lock_slowpath()	__pv_queued_spin_lock_slowpath()
  native_queued_spin_unlock()		__pv_queued_spin_unlock()

We use a callee saved call for the unlock function which reduces the
i-cache footprint and allows 'inlining' of SPIN_UNLOCK functions
again.

We further optimize the unlock path by patching the direct call with a
"movb $0,%arg1" if we are indeed using the native unlock code. This
makes the unlock code almost as fast as the !PARAVIRT case.

This significantly lowers the overhead of having
CONFIG_PARAVIRT_SPINLOCKS enabled, even for native code.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-10-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:37:09 +02:00
Waiman Long
a23db284fe locking/pvqspinlock: Implement simple paravirt support for the qspinlock
Provide a separate (second) version of the spin_lock_slowpath for
paravirt along with a special unlock path.

The second slowpath is generated by adding a few pv hooks to the
normal slowpath, but where those will compile away for the native
case, they expand into special wait/wake code for the pv version.

The actual MCS queue can use extra storage in the mcs_nodes[] array to
keep track of state and therefore uses directed wakeups.

The head contender has no such storage directly visible to the
unlocker.  So the unlocker searches a hash table with open addressing
using a simple binary Galois linear feedback shift register.

Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1429901803-29771-9-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:37:05 +02:00
Peter Zijlstra (Intel)
2aa79af642 locking/qspinlock: Revert to test-and-set on hypervisors
When we detect a hypervisor (!paravirt, see qspinlock paravirt support
patches), revert to a simple test-and-set lock to avoid the horrors
of queue preemption.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-8-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:58 +02:00
Waiman Long
2c83e8e949 locking/qspinlock: Use a simple write to grab the lock
Currently, atomic_cmpxchg() is used to get the lock. However, this
is not really necessary if there is more than one task in the queue
and the queue head don't need to reset the tail code. For that case,
a simple write to set the lock bit is enough as the queue head will
be the only one eligible to get the lock as long as it checks that
both the lock and pending bits are not set. The current pending bit
waiting code will ensure that the bit will not be set as soon as the
tail code in the lock is set.

With that change, the are some slight improvement in the performance
of the queued spinlock in the 5M loop micro-benchmark run on a 4-socket
Westere-EX machine as shown in the tables below.

		[Standalone/Embedded - same node]
  # of tasks	Before patch	After patch	%Change
  ----------	-----------	----------	-------
       3	 2324/2321	2248/2265	 -3%/-2%
       4	 2890/2896	2819/2831	 -2%/-2%
       5	 3611/3595	3522/3512	 -2%/-2%
       6	 4281/4276	4173/4160	 -3%/-3%
       7	 5018/5001	4875/4861	 -3%/-3%
       8	 5759/5750	5563/5568	 -3%/-3%

		[Standalone/Embedded - different nodes]
  # of tasks	Before patch	After patch	%Change
  ----------	-----------	----------	-------
       3	12242/12237	12087/12093	 -1%/-1%
       4	10688/10696	10507/10521	 -2%/-2%

It was also found that this change produced a much bigger performance
improvement in the newer IvyBridge-EX chip and was essentially to close
the performance gap between the ticket spinlock and queued spinlock.

The disk workload of the AIM7 benchmark was run on a 4-socket
Westmere-EX machine with both ext4 and xfs RAM disks at 3000 users
on a 3.14 based kernel. The results of the test runs were:

                AIM7 XFS Disk Test
  kernel                 JPM    Real Time   Sys Time    Usr Time
  -----                  ---    ---------   --------    --------
  ticketlock            5678233    3.17       96.61       5.81
  qspinlock             5750799    3.13       94.83       5.97

                AIM7 EXT4 Disk Test
  kernel                 JPM    Real Time   Sys Time    Usr Time
  -----                  ---    ---------   --------    --------
  ticketlock            1114551   16.15      509.72       7.11
  qspinlock             2184466    8.24      232.99       6.01

The ext4 filesystem run had a much higher spinlock contention than
the xfs filesystem run.

The "ebizzy -m" test was also run with the following results:

  kernel               records/s  Real Time   Sys Time    Usr Time
  -----                ---------  ---------   --------    --------
  ticketlock             2075       10.00      216.35       3.49
  qspinlock              3023       10.00      198.20       4.80

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-7-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:55 +02:00
Peter Zijlstra (Intel)
69f9cae909 locking/qspinlock: Optimize for smaller NR_CPUS
When we allow for a max NR_CPUS < 2^14 we can optimize the pending
wait-acquire and the xchg_tail() operations.

By growing the pending bit to a byte, we reduce the tail to 16bit.
This means we can use xchg16 for the tail part and do away with all
the repeated compxchg() operations.

This in turn allows us to unconditionally acquire; the locked state
as observed by the wait loops cannot change. And because both locked
and pending are now a full byte we can use simple stores for the
state transition, obviating one atomic operation entirely.

This optimization is needed to make the qspinlock achieve performance
parity with ticket spinlock at light load.

All this is horribly broken on Alpha pre EV56 (and any other arch that
cannot do single-copy atomic byte stores).

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-6-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:48 +02:00
Waiman Long
6403bd7d0e locking/qspinlock: Extract out code snippets for the next patch
This is a preparatory patch that extracts out the following 2 code
snippets to prepare for the next performance optimization patch.

 1) the logic for the exchange of new and previous tail code words
    into a new xchg_tail() function.
 2) the logic for clearing the pending bit and setting the locked bit
    into a new clear_pending_set_locked() function.

This patch also simplifies the trylock operation before queuing by
calling queued_spin_trylock() directly.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-5-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:41 +02:00
Peter Zijlstra (Intel)
c1fb159db9 locking/qspinlock: Add pending bit
Because the qspinlock needs to touch a second cacheline (the per-cpu
mcs_nodes[]); add a pending bit and allow a single in-word spinner
before we punt to the second cacheline.

It is possible so observe the pending bit without the locked bit when
the last owner has just released but the pending owner has not yet
taken ownership.

In this case we would normally queue -- because the pending bit is
already taken. However, in this case the pending bit is guaranteed
to be released 'soon', therefore wait for it and avoid queueing.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-4-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:32 +02:00
Waiman Long
d73a33973f locking/qspinlock, x86: Enable x86-64 to use queued spinlocks
This patch makes the necessary changes at the x86 architecture
specific layer to enable the use of queued spinlocks for x86-64. As
x86-32 machines are typically not multi-socket. The benefit of queue
spinlock may not be apparent. So queued spinlocks are not enabled.

Currently, there is some incompatibilities between the para-virtualized
spinlock code (which hard-codes the use of ticket spinlock) and the
queued spinlocks. Therefore, the use of queued spinlocks is disabled
when the para-virtualized spinlock is enabled.

The arch/x86/include/asm/qspinlock.h header file includes some x86
specific optimization which will make the queueds spinlock code
perform better than the generic implementation.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-3-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:26 +02:00
Waiman Long
a33fda35e3 locking/qspinlock: Introduce a simple generic 4-byte queued spinlock
This patch introduces a new generic queued spinlock implementation that
can serve as an alternative to the default ticket spinlock. Compared
with the ticket spinlock, this queued spinlock should be almost as fair
as the ticket spinlock. It has about the same speed in single-thread
and it can be much faster in high contention situations especially when
the spinlock is embedded within the data structure to be protected.

Only in light to moderate contention where the average queue depth
is around 1-3 will this queued spinlock be potentially a bit slower
due to the higher slowpath overhead.

This queued spinlock is especially suit to NUMA machines with a large
number of cores as the chance of spinlock contention is much higher
in those machines. The cost of contention is also higher because of
slower inter-node memory traffic.

Due to the fact that spinlocks are acquired with preemption disabled,
the process will not be migrated to another CPU while it is trying
to get a spinlock. Ignoring interrupt handling, a CPU can only be
contending in one spinlock at any one time. Counting soft IRQ, hard
IRQ and NMI, a CPU can only have a maximum of 4 concurrent lock waiting
activities.  By allocating a set of per-cpu queue nodes and used them
to form a waiting queue, we can encode the queue node address into a
much smaller 24-bit size (including CPU number and queue node index)
leaving one byte for the lock.

Please note that the queue node is only needed when waiting for the
lock. Once the lock is acquired, the queue node can be released to
be used later.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-2-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:25 +02:00
Preeti U Murthy
663fdcbee0 kernel: Replace reference to ASSIGN_ONCE() with WRITE_ONCE() in comment
Looks like commit :

 43239cbe79 ("kernel: Change ASSIGN_ONCE(val, x) to WRITE_ONCE(x, val)")

left behind a reference to ASSIGN_ONCE(). Update this to WRITE_ONCE().

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: borntraeger@de.ibm.com
Cc: dave@stgolabs.net
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20150430115721.22278.94082.stgit@preeti.in.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:28:53 +02:00
Waiman Long
59aabfc7e9 locking/rwsem: Reduce spinlock contention in wakeup after up_read()/up_write()
In up_write()/up_read(), rwsem_wake() will be called whenever it
detects that some writers/readers are waiting. The rwsem_wake()
function will take the wait_lock and call __rwsem_do_wake() to do the
real wakeup.  For a heavily contended rwsem, doing a spin_lock() on
wait_lock will cause further contention on the heavily contended rwsem
cacheline resulting in delay in the completion of the up_read/up_write
operations.

This patch makes the wait_lock taking and the call to __rwsem_do_wake()
optional if at least one spinning writer is present. The spinning
writer will be able to take the rwsem and call rwsem_wake() later
when it calls up_write(). With the presence of a spinning writer,
rwsem_wake() will now try to acquire the lock using trylock. If that
fails, it will just quit.

Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Jason Low <jason.low2@hp.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1430428337-16802-2-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:27:59 +02:00
Michael Ellerman
cb30711374 perf_event: Don't allow vmalloc() backed perf on powerpc
On powerpc the perf event interrupt is not masked when interrupts are
disabled, allowing it to function as an NMI.

This causes problems if perf is using vmalloc. If we take a page fault
on the vmalloc region the fault handler will fail the page fault because
it detects we are coming in from an NMI (see do_hash_page()).

We don't actually need or want vmalloc backed perf so just disable it on
powerpc.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <linuxppc-dev@ozlabs.org>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@ghostprotocols.net
Cc: sukadev@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1430720799-18426-1-git-send-email-mpe@ellerman.id.au
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:26:01 +02:00