Commit Graph

858756 Commits

Author SHA1 Message Date
Olof Johansson
c3bd15a078 Merge tag 'omap-for-v5.3/ti-sysc-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into arm/drivers
ti-sysc interconnect target module driver changes for v5.3

This series of changes improves probing devices with ti-sysc to the
point where we can now probe most devices without the custom dts
property "ti,hwmods" and no legacy platform data :)

We add support for platform data callbacks for idling and unidling the
clockdomain the module belongs to. The rest of the series mostly adds
handling for the various quirks needed by old legacy modules such as
i2c and watchdog. Some quirk handling is still missing for few modules,
but those will be added as they get tested.

The related platform data and dts changes will be sent separately.

* tag 'omap-for-v5.3/ti-sysc-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  bus: ti-sysc: Add support for module specific reset quirks
  bus: ti-sysc: Detect uarts also on omap34xx
  bus: ti-sysc: Do rstctrl reset handling in two phases
  bus: ti-sysc: Add support for disabling module without legacy mode
  bus: ti-sysc: Set ENAWAKEUP if available
  bus: ti-sysc: Handle swsup idle mode quirks
  bus: ti-sysc: Handle clockactivity for enable and disable
  bus: ti-sysc: Enable interconnect target module autoidle bit on enable
  bus: ti-sysc: Allow QUIRK_LEGACY_IDLE even if legacy_mode is not set
  bus: ti-sysc: Make OCP reset work for sysstatus and sysconfig reset bits
  bus: ti-sysc: Support 16-bit writes too
  bus: ti-sysc: Add support for missing clockdomain handling
  ARM: dts: dra71x: Disable usb4_tm target module
  ARM: dts: dra71x: Disable rtc target module
  ARM: dts: dra76x: Disable usb4_tm target module
  ARM: dts: dra76x: Disable rtc target module
  ARM: dts: dra76x: Update MMC2_HS200_MANUAL1 iodelay values
  ARM: dts: am57xx-idk: Remove support for voltage switching for SD card
  bus: ti-sysc: Handle devices with no control registers
  ARM: dts: Configure osc clock for d_can on am335x

Signed-off-by: Olof Johansson <olof@lixom.net>
2019-06-17 04:53:32 -07:00
Olof Johansson
426356392c Merge tag 'arm-soc/for-5.3/drivers' of https://github.com/Broadcom/stblinux into arm/drivers
This pull request contains Broadcom ARM/ARM64/MIPS SoCs drivers changes
for 5.3, please pull the following:

- Markus provides a set of updates to the DPFE driver to support a new
  revision of the API to the firmware (version 3) and provides minor fixes
  about how the MR4-8 words are read for LPDDR4 devices

- Florian removes a print of a virtual address in brcmstb_gisb.c

* tag 'arm-soc/for-5.3/drivers' of https://github.com/Broadcom/stblinux:
  memory: brcmstb: dpfe: introduce DPFE API v3
  memory: brcmstb: dpfe: prepare for API-dependent sysfs attributes
  memory: brcmstb: dpfe: prepare support for multiple API versions
  memory: brcmstb: dpfe: wait for DCPU to be ready
  memory: brcmstb: dpfe: report firmware loading error
  memory: brcmstb: dpfe: remove unused code and fix formatting
  bus: brcmstb_gisb: Remove print of base address
  memory: brcmstb: dpfe: use byte 3 of registers MR4-MR8
  memory: brcmstb: dpfe: optimize generic_show()
  memory: brcmstb: dpfe: use msleep() over udelay()

Signed-off-by: Olof Johansson <olof@lixom.net>
2019-06-17 04:52:52 -07:00
Jean-Philippe Brucker
92e074acf6 firmware/psci: psci_checker: Park kthreads before stopping them
Since commit 85f1abe001 ("kthread, sched/wait: Fix kthread_parkme()
completion issue"), kthreads that are bound to a CPU must be parked
before being stopped. At the moment the PSCI checker calls
kthread_stop() directly on the suspend kthread, which triggers the
following warning:

[    6.068288] WARNING: CPU: 1 PID: 1 at kernel/kthread.c:398 __kthread_bind_mask+0x20/0x78
               ...
[    6.190151] Call trace:
[    6.192566]  __kthread_bind_mask+0x20/0x78
[    6.196615]  kthread_unpark+0x74/0x80
[    6.200235]  kthread_stop+0x44/0x1d8
[    6.203769]  psci_checker+0x3bc/0x484
[    6.207389]  do_one_initcall+0x48/0x260
[    6.211180]  kernel_init_freeable+0x2c8/0x368
[    6.215488]  kernel_init+0x10/0x100
[    6.218935]  ret_from_fork+0x10/0x1c
[    6.222467] ---[ end trace e05e22863d043cd3 ]---

kthread_unpark() tries to bind the thread to its CPU and aborts with a
WARN() if the thread wasn't in TASK_PARKED state. Park the kthreads
before stopping them.

Fixes: 85f1abe001 ("kthread, sched/wait: Fix kthread_parkme() completion issue")
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2019-06-17 04:50:21 -07:00
Masahiro Yamada
5ec47cda74 memory: move jedec_ddr.h from include/memory to drivers/memory/
Now that jedec_ddr_data.c was moved from lib/ to drivers/memory/,
<memory/jedec_ddr.h> is included only from drivers/memory/.

Make it a local header of drivers/memory/.

The directory include/memory is now gone.

While I am here, I also changed #include <linux/module.h> to
<linux/export.h>. Because CONFIG_DDR is bool, jedec_ddr_data.c is
never compiled as a module.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2019-06-17 04:45:21 -07:00
Masahiro Yamada
7b43b8fdc9 memory: move jedec_ddr_data.c from lib/ to drivers/memory/
jedec_ddr_data.c exports 3 symbols, and all of them are only
referenced from drivers/memory/{emif.c,of_memory.c}

drivers/memory/ is a better location than lib/.

I removed the Kconfig prompt "JEDEC DDR data" because it is only
select'ed by TI_EMIF, and there is no other user. There is no good
reason in making it a user-configurable CONFIG option.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2019-06-17 04:45:17 -07:00
Olof Johansson
c9727db7cc Merge tag 'tee-maint-for-5.3' of https://git.linaro.org/people/jens.wiklander/linux-tee into arm/drivers
Adding mailing list for TEE subsystem

* tag 'tee-maint-for-5.3' of https://git.linaro.org/people/jens.wiklander/linux-tee:
  MAINTAINERS: Add mailing list for the TEE subsystem

Signed-off-by: Olof Johansson <olof@lixom.net>
2019-06-17 04:40:41 -07:00
Olof Johansson
1126037393 Merge tag 'soc-fsl-next-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/leo/linux into arm/drivers
NXP/FSL SoC driver updates for v5.3

DPAA2 Console driver
- Add driver to export two char devices to dump logs for MC and
  AIOP

DPAA2 DPIO driver
- Add support for memory backed QBMan portals
- Increase the timeout period to prevent false error
- Add APIs to retrieve QBMan portal probing status

DPAA Qman driver
- Only make liodn fixup on powerpc SoCs with PAMU iommu

* tag 'soc-fsl-next-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/leo/linux:
  soc: fsl: qbman_portals: add APIs to retrieve the probing status
  soc: fsl: qman: fixup liodns only on ppc targets
  soc: fsl: dpio: Add support for memory backed QBMan portals
  bus: mc-bus: Add support for mapping shareable portals
  soc: fsl: dpio: Increase timeout for QBMan Management Commands
  soc: fsl: add DPAA2 console support
  Documentation: DT: Add entry for DPAA2 console
  soc: fsl: guts: Add definition for LX2160A

Signed-off-by: Olof Johansson <olof@lixom.net>
2019-06-17 04:38:06 -07:00
Yangbo Lu
791463ba1a mmc: sdhci-of-esdhc: use 1/2 periperhal clock for ls1028a
LS1028A used 1/2 periperhal clock as one reference clock.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:33:54 +02:00
Yangbo Lu
04509d7709 mmc: sdhci-of-esdhc: set the sd clock divisor value above 3
This patch is to set the sd clock divisor value above 3 in tuning mode

Signed-off-by: Yinbo Zhu <yinbo.zhu@nxp.com>
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:33:44 +02:00
Eric Farman
01aa26c672 s390/cio: Combine direct and indirect CCW paths
With both the direct-addressed and indirect-addressed CCW paths
simplified to this point, the amount of shared code between them is
(hopefully) more easily visible.  Move the processing of IDA-specific
bits into the direct-addressed path, and add some useful commentary of
what the individual pieces are doing.  This allows us to remove the
entire ccwchain_fetch_idal() routine and maintain a single function
for any non-TIC CCW.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-10-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:31:41 +02:00
Greg Kroah-Hartman
5928d8929d mmc: host: s3cmci: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Also, because there is no need to save the file dentries, remove them
from the host-specific structure and just recursively delete the
directory that the driver created, when shutting down.

Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:31:29 +02:00
Greg Kroah-Hartman
fcac152782 mmc: host: dw_mmc: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this

Cc: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:31:21 +02:00
Eric Farman
e8573b39a8 vfio-ccw: Rearrange IDAL allocation in direct CCW
This is purely deck furniture, to help understand the merge of the
direct and indirect handlers.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-9-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:31:17 +02:00
Greg Kroah-Hartman
091eb12f62 mmc: host: atmel-mci: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:30:54 +02:00
Greg Kroah-Hartman
a04c50aaa9 mmc: core: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:30:49 +02:00
Eric Farman
e7eaf91b0a vfio-ccw: Remove pfn_array_table
Now that both CCW codepaths build this nested array:

  ccwchain->pfn_array_table[1]->pfn_array[#idaws/#pages]

We can collapse this into simply:

  ccwchain->pfn_array[#idaws/#pages]

Let's do that, so that we don't have to continually navigate two
nested arrays when the first array always has a count of one.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-8-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:30:46 +02:00
Eric Farman
8aabf0edae vfio-ccw: Adjust the first IDAW outside of the nested loops
Now that pfn_array_table[] is always an array of 1, it seems silly to
check for the very first entry in an array in the middle of two nested
loops, since we know it'll only ever happen once.

Let's move this outside the loops to simplify things, even though
the "k" variable is still necessary.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-7-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:30:25 +02:00
Eric Farman
cc06ee983c vfio-ccw: Rearrange pfn_array and pfn_array_table arrays
While processing a channel program, we currently have two nested
arrays that carry a slightly different structure.  The direct CCW
path creates this:

  ccwchain->pfn_array_table[1]->pfn_array[#pages]

while an IDA CCW creates:

  ccwchain->pfn_array_table[#idaws]->pfn_array[1]

The distinction appears to state that each pfn_array_table entry
points to an array of contiguous pages, represented by a pfn_array,
um, array.  Since the direct-addressed scenario can ONLY represent
contiguous pages, it makes the intermediate array necessary but
difficult to recognize.  Meanwhile, since an IDAL can contain
non-contiguous pages and there is no logic in vfio-ccw to detect
adjacent IDAWs, it is the second array that is necessary but appearing
to be superfluous.

I am not aware of any documentation that states the pfn_array[] needs
to be of contiguous pages; it is just what the code does today.
I don't see any reason for this either, let's just flip the IDA
codepath around so that it generates:

  ch_pat->pfn_array_table[1]->pfn_array[#idaws]

This will bring it in line with the direct-addressed codepath,
so that we can understand the behavior of this memory regardless
of what type of CCW is being processed.  And it means the casual
observer does not need to know/care whether the pfn_array[]
represents contiguous pages or not.

NB: The existing vfio-ccw code only supports 4K-block Format-2 IDAs,
so that "#pages" == "#idaws" in this area.  This means that we will
have difficulty with this overlap in terminology if support for
Format-1 or 2K-block Format-2 IDAs is ever added.  I don't think that
this patch changes our ability to make that distinction.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-6-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:30:00 +02:00
Eric Farman
99afcb05d9 s390/cio: Use generalized CCW handler in cp_init()
It is now pretty apparent that ccwchain_handle_ccw()
(nee ccwchain_handle_tic()) does everything that cp_init()
wants to do.

Let's remove that duplicated code from cp_init() and let
ccwchain_handle_ccw() handle it itself.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-5-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:29:33 +02:00
Eric Farman
363fe5f7ae s390/cio: Generalize the TIC handler
Refactor ccwchain_handle_tic() into a routine that handles a channel
program address (which itself is a CCW pointer), rather than a CCW pointer
that is only a TIC CCW.  This will make it easier to reuse this code for
other CCW commands.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-4-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:29:10 +02:00
Eric Farman
e64bd68946 s390/cio: Refactor the routine that handles TIC CCWs
Extract the "does the target of this TIC already exist?" check from
ccwchain_handle_tic(), so that it's easier to refactor that function
into one that cp_init() is able to use.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-3-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:28:50 +02:00
Eric Farman
812271b910 s390/cio: Squash cp_free() and cp_unpin_free()
The routine cp_free() does nothing but call cp_unpin_free(), and while
most places call cp_free() there is one caller of cp_unpin_free() used
when the cp is guaranteed to have not been marked initialized.

This seems like a dubious way to make a distinction, so let's combine
these routines and make cp_free() do all the work.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190606202831.44135-2-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-17 13:28:29 +02:00
Ulf Hansson
163367c952 Merge branch 'fixes' into next 2019-06-17 13:28:12 +02:00
jjian zhou
20314ce30a mmc: mediatek: fix SDIO IRQ detection issue
If cmd19 timeout or response crcerr occurs during execute_tuning(),
it need invoke msdc_reset_hw(). Otherwise SDIO IRQ can't be detected.

Signed-off-by: jjian zhou <jjian.zhou@mediatek.com>
Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Yong Mao <yong.mao@mediatek.com>
Fixes: 5215b2e952 ("mmc: mediatek: Add MMC_CAP_SDIO_IRQ support")
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:26:50 +02:00
jjian zhou
8a5df8ac62 mmc: mediatek: fix SDIO IRQ interrupt handle flow
SDIO IRQ is triggered by low level. It need disable SDIO IRQ
detected function. Otherwise the interrupt register can't be cleared.
It will process the interrupt more.

Signed-off-by: Jjian Zhou <jjian.zhou@mediatek.com>
Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Yong Mao <yong.mao@mediatek.com>
Fixes: 5215b2e952 ("mmc: mediatek: Add MMC_CAP_SDIO_IRQ support")
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:25:44 +02:00
Ley Foon Tan
7a28db0a25 PCI: altera: Fix configuration type based on secondary number
Stratix 10 PCIe controller does not support Type 1 to Type 0 conversion
as previous version (V1) does so the PCIe controller configuration
mechanism needs to send Type 0 config TLP if the target bus number
matches with the secondary bus number.

Implement a function to form a TLP header that depends on the PCIe
controller version, so that the header can be formed according to
specific host controller HW internals, fixing the type conversion issue.

Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2019-06-17 12:22:25 +01:00
Wolfram Sang
b0e370b95a mmc: core: complete HS400 before checking status
We don't have a reproducible error case, yet our BSP team suggested that
the mmc_switch_status() command in mmc_select_hs400() should come after
the callback into the driver completing HS400 setup. It makes sense to
me because we want the status of a fully setup HS400, so it will
increase the reliability of the mmc_switch_status() command.

Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Fixes: ba6c7ac3a2 ("mmc: core: more fine-grained hooks for HS400 tuning")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-17 13:18:11 +02:00
Miquel Raynal
c369b536f8 PCI: armada8k: Add PHYs support
Bring PHY support for the Armada8k driver.

The Armada8k IP only supports x1, x2 or x4 link widths. Iterate over
the DT 'phys' entries and configure them one by one. Use
phy_set_mode_ext() to make use of the submode parameter (initially
introduced for Ethernet modes). For PCI configuration, let the submode
be the width (1, 2, 4, etc) so that the PHY driver knows how many
lanes are bundled. Do not error out in case of error for compatibility
reasons.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
2019-06-17 12:15:07 +01:00
Masayoshi Mizuma
8f5c9037a5 arm64/mm: Correct the cache line size warning with non coherent device
If the cache line size is greater than ARCH_DMA_MINALIGN (128),
the warning shows and it's tainted as TAINT_CPU_OUT_OF_SPEC.

However, it's not good because as discussed in the thread [1], the cpu
cache line size will be problem only on non-coherent devices.

Since the coherent flag is already introduced to struct device,
show the warning only if the device is non-coherent device and
ARCH_DMA_MINALIGN is smaller than the cpu cache size.

[1] https://lore.kernel.org/linux-arm-kernel/20180514145703.celnlobzn3uh5tc2@localhost/

Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Tested-by: Zhang Lei <zhang.lei@jp.fujitsu.com>
[catalin.marinas@arm.com: removed 'if' block for WARN_TAINT]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-06-17 11:52:47 +01:00
ShihPo Hung
bf587caae3 riscv: mm: synchronize MMU after pte change
Because RISC-V compliant implementations can cache invalid entries
in TLB, an SFENCE.VMA is necessary after changes to the page table.
This patch adds an SFENCE.vma for the vmalloc_fault path.

Signed-off-by: ShihPo Hung <shihpo.hung@sifive.com>
[paul.walmsley@sifive.com: reversed tab->whitespace conversion,
 wrapped comment lines]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: linux-riscv@lists.infradead.org
Cc: stable@vger.kernel.org
2019-06-17 03:44:44 -07:00
Peter Zijlstra
2234a6d3a2 x86/percpu: Optimize raw_cpu_xchg()
Since raw_cpu_xchg() doesn't need to be IRQ-safe, like
this_cpu_xchg(), we can use a simple load-store instead of the cmpxchg
loop.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:43:44 +02:00
Peter Zijlstra
8dc2d993cf x86/percpu, sched/fair: Avoid local_clock()
Nadav reported that code-gen changed because of the this_cpu_*()
constraints, avoid this for select_idle_cpu() because that runs with
preemption (and IRQs) disabled anyway.

Reported-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:43:43 +02:00
Peter Zijlstra
602447f954 x86/percpu, x86/irq: Relax {set,get}_irq_regs()
Nadav reported that since the this_cpu_*() ops got asm-volatile
constraints on, code generation suffered for do_IRQ(), but since this
is all with IRQs disabled we can use __this_cpu_*().

  smp_x86_platform_ipi                                      234        222   -12,+0
  smp_kvm_posted_intr_ipi                                    74         66   -8,+0
  smp_kvm_posted_intr_wakeup_ipi                             86         78   -8,+0
  smp_apic_timer_interrupt                                  292        284   -8,+0
  smp_kvm_posted_intr_nested_ipi                             74         66   -8,+0
  do_IRQ                                                    195        187   -8,+0

Reported-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:43:42 +02:00
Peter Zijlstra
9ed7d75b2f x86/percpu: Relax smp_processor_id()
Nadav reported that since this_cpu_read() became asm-volatile, many
smp_processor_id() users generated worse code due to the extra
constraints.

However since smp_processor_id() is reading a stable value, we can use
__this_cpu_read().

While this does reduce text size somewhat, this mostly results in code
movement to .text.unlikely as a result of more/larger .cold.
subfunctions. Less text on the hotpath is good for I$.

  $ ./compare.sh defconfig-build1 defconfig-build2 vmlinux.o
  setup_APIC_ibs                                             90         98   -12,+20
  force_ibs_eilvt_setup                                     400        413   -57,+70
  pci_serr_error                                            109        104   -54,+49
  pci_serr_error                                            109        104   -54,+49
  unknown_nmi_error                                         125        120   -76,+71
  unknown_nmi_error                                         125        120   -76,+71
  io_check_error                                            125        132   -97,+104
  intel_thermal_interrupt                                   730        822   +92,+0
  intel_init_thermal                                        951        945   -6,+0
  generic_get_mtrr                                          301        294   -7,+0
  generic_get_mtrr                                          301        294   -7,+0
  generic_set_all                                           749        754   -44,+49
  get_fixed_ranges                                          352        360   -41,+49
  x86_acpi_suspend_lowlevel                                 369        363   -6,+0
  check_tsc_sync_source                                     412        412   -71,+71
  irq_migrate_all_off_this_cpu                              662        674   -14,+26
  clocksource_watchdog                                      748        748   -113,+113
  __perf_event_account_interrupt                            204        197   -7,+0
  attempt_merge                                            1748       1741   -7,+0
  intel_guc_send_ct                                        1424       1409   -15,+0
  __fini_doorbell                                           235        231   -4,+0
  bdw_set_cdclk                                             928        923   -5,+0
  gen11_dsi_disable                                        1571       1556   -15,+0
  gmbus_wait                                                493        488   -5,+0
  md_make_request                                           376        369   -7,+0
  __split_and_process_bio                                   543        536   -7,+0
  delay_tsc                                                  96         89   -7,+0
  hsw_disable_pc8                                           696        691   -5,+0
  tsc_verify_tsc_adjust                                     215        228   -22,+35
  cpuidle_driver_unref                                       56         49   -7,+0
  blk_account_io_completion                                 159        148   -11,+0
  mtrr_wrmsr                                                 95         99   -29,+33
  __intel_wait_for_register_fw                              401        419   +18,+0
  cpuidle_driver_ref                                         43         36   -7,+0
  cpuidle_get_driver                                         15          8   -7,+0
  blk_account_io_done                                       535        528   -7,+0
  irq_migrate_all_off_this_cpu                              662        674   -14,+26
  check_tsc_sync_source                                     412        412   -71,+71
  irq_wait_for_poll                                         170        163   -7,+0
  generic_end_io_acct                                       329        322   -7,+0
  x86_acpi_suspend_lowlevel                                 369        363   -6,+0
  nohz_balance_enter_idle                                   198        191   -7,+0
  generic_start_io_acct                                     254        247   -7,+0
  blk_account_io_start                                      341        334   -7,+0
  perf_event_task_tick                                      682        675   -7,+0
  intel_init_thermal                                        951        945   -6,+0
  amd_e400_c1e_apic_setup                                    47         51   -28,+32
  setup_APIC_eilvt                                          350        328   -22,+0
  hsw_enable_pc8                                           1611       1605   -6,+0
                                               total   12985947   12985892   -994,+939

Reported-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:43:41 +02:00
Peter Zijlstra
0b9ccc0a9b x86/percpu: Differentiate this_cpu_{}() and __this_cpu_{}()
Nadav Amit reported that commit:

  b59167ac7b ("x86/percpu: Fix this_cpu_read()")

added a bunch of constraints to all sorts of code; and while some of
that was correct and desired, some of that seems superfluous.

The thing is, the this_cpu_*() operations are defined IRQ-safe, this
means the values are subject to change from IRQs, and thus must be
reloaded.

Also, the generic form:

  local_irq_save()
  __this_cpu_read()
  local_irq_restore()

would not allow the re-use of previous values; if by nothing else,
then the barrier()s implied by local_irq_*().

Which raises the point that percpu_from_op() and the others also need
that volatile.

OTOH __this_cpu_*() operations are not IRQ-safe and assume external
preempt/IRQ disabling and could thus be allowed more room for
optimization.

This makes the this_cpu_*() vs __this_cpu_*() behaviour more
consistent with other architectures.

  $ ./compare.sh defconfig-build defconfig-build1 vmlinux.o
  x86_pmu_cancel_txn                                         80         71   -9,+0
  __text_poke                                               919        964   +45,+0
  do_user_addr_fault                                       1082       1058   -24,+0
  __do_page_fault                                          1194       1178   -16,+0
  do_exit                                                  2995       3027   -43,+75
  process_one_work                                         1008        989   -67,+48
  finish_task_switch                                        524        505   -19,+0
  __schedule_bug                                            103         98   -59,+54
  __schedule_bug                                            103         98   -59,+54
  __sched_setscheduler                                     2015       2030   +15,+0
  freeze_processes                                          203        230   +31,-4
  rcu_gp_kthread_wake                                       106         99   -7,+0
  rcu_core                                                 1841       1834   -7,+0
  call_timer_fn                                             298        286   -12,+0
  can_stop_idle_tick                                        146        139   -31,+24
  perf_pending_event                                        253        239   -14,+0
  shmem_alloc_page                                          209        213   +4,+0
  __alloc_pages_slowpath                                   3284       3269   -15,+0
  umount_tree                                               671        694   +23,+0
  advance_transaction                                       803        798   -5,+0
  con_put_char                                               71         51   -20,+0
  xhci_urb_enqueue                                         1302       1295   -7,+0
  xhci_urb_enqueue                                         1302       1295   -7,+0
  tcp_sacktag_write_queue                                  2130       2075   -55,+0
  tcp_try_undo_loss                                         229        208   -21,+0
  tcp_v4_inbound_md5_hash                                   438        411   -31,+4
  tcp_v4_inbound_md5_hash                                   438        411   -31,+4
  tcp_v6_inbound_md5_hash                                   469        411   -33,-25
  tcp_v6_inbound_md5_hash                                   469        411   -33,-25
  restricted_pointer                                        434        420   -14,+0
  irq_exit                                                  162        154   -8,+0
  get_perf_callchain                                        638        624   -14,+0
  rt_mutex_trylock                                          169        156   -13,+0
  avc_has_extended_perms                                   1092       1089   -3,+0
  avc_has_perm_noaudit                                      309        306   -3,+0
  __perf_sw_event                                           138        122   -16,+0
  perf_swevent_get_recursion_context                        116        102   -14,+0
  __local_bh_enable_ip                                       93         72   -21,+0
  xfrm_input                                               4175       4161   -14,+0
  avc_has_perm                                              446        443   -3,+0
  vm_events_fold_cpu                                         57         56   -1,+0
  vfree                                                      68         61   -7,+0
  freeze_processes                                          203        230   +31,-4
  _local_bh_enable                                           44         30   -14,+0
  ip_do_fragment                                           1982       1944   -38,+0
  do_exit                                                  2995       3027   -43,+75
  __do_softirq                                              742        724   -18,+0
  cpu_init                                                 1510       1489   -21,+0
  account_system_time                                        80         79   -1,+0
                                               total   12985281   12984819   -742,+280

Reported-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20181206112433.GB13675@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:43:40 +02:00
Will Deacon
c584b1202f MAINTAINERS: Update my email address to use @kernel.org
My @arm.com address will stop working at the end of August, so update to
my @kernel.org address where you'll still be able to reach me.

When I say "stop working" I really mean "will go to my line manager", so
send patches there at your peril because they may reply with roadmaps
and spreadsheets. You have been warned.

Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: arm-soc <arm@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-06-17 11:37:01 +01:00
Jiri Olsa
d0e1a507bd perf/x86/intel: Disable check_msr for real HW
Tom Vaden reported false failure of the check_msr() function, because
some servers can do POST tracing and enable LBR tracing during
bootup.

Kan confirmed that check_msr patch was to fix a bug report in
guest, so it's ok to disable it for real HW.

Reported-by: Tom Vaden <tom.vaden@hpe.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tom Vaden <tom.vaden@hpe.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Liang Kan <kan.liang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190616141313.GD2500@krava
[ Readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:24 +02:00
Jiri Olsa
b7c9b39273 perf/x86/intel: Use ->is_visible callback for default group
It's preffered to use group's ->is_visible callback, so
we do not need to use condition attribute assignment.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190524132152.GB26617@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:23 +02:00
Kan Liang
ee49532b38 perf/x86/intel/uncore: Add IMC uncore support for Snow Ridge
IMC uncore unit can only be accessed via MMIO on Snow Ridge.
The MMIO space of IMC uncore is at the specified offsets from the
MEM0_BAR. Add snr_uncore_get_mc_dev() to locate the PCI device with
MMIO_BASE and MEM0_BAR register.

Add new ops to access the IMC registers via MMIO.

Add 3 new free running counters for clocks, read and write bandwidth.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: eranian@google.com
Link: https://lkml.kernel.org/r/1556672028-119221-7-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:22 +02:00
Kan Liang
07ce734dd8 perf/x86/intel/uncore: Clean up client IMC
The client IMC block is accessed by MMIO. Current code uses an informal
way to access the block, which is not recommended.

Clean up the code by using __iomem annotation and the accessor
functions (read[lq]()).

Move exit_box() and read_counter() to generic code, which can be shared
with the server code later.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: eranian@google.com
Link: https://lkml.kernel.org/r/1556672028-119221-6-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:21 +02:00
Kan Liang
3da04b8a00 perf/x86/intel/uncore: Support MMIO type uncore blocks
A new MMIO type uncore box is introduced on Snow Ridge server. The
counters of MMIO type uncore box can only be accessed by MMIO.

Add a new uncore type, uncore_mmio_uncores, for MMIO type uncore blocks.

Support MMIO type uncore blocks in CPU hot plug. The MMIO space has to
be map/unmap for the first/last CPU. The context also need to be
migrated if the bind CPU changes.

Add mmio_init() to init and register PMUs for MMIO type uncore blocks.

Add a helper to calculate the box_ctl address.

The helpers which calculate ctl/ctr can be shared with PCI type uncore
blocks.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: eranian@google.com
Link: https://lkml.kernel.org/r/1556672028-119221-5-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:20 +02:00
Kan Liang
c8872d90e0 perf/x86/intel/uncore: Factor out box ref/unref functions
For uncore box which can only be accessed by MSR, its reference
box->refcnt is updated in CPU hot plug. The uncore boxes need to be
initalized and exited accordingly for the first/last CPU of a socket.

Starts from Snow Ridge server, a new type of uncore box is introduced,
which can only be accessed by MMIO. The driver needs to map/unmap
MMIO space for the first/last CPU of a socket.

Extract the codes of box ref/unref and init/exit for reuse later.

There is no functional change.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: eranian@google.com
Link: https://lkml.kernel.org/r/1556672028-119221-4-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:19 +02:00
Kan Liang
210cc5f9db perf/x86/intel/uncore: Add uncore support for Snow Ridge server
The uncore subsystem on Snow Ridge is similar as previous SKX server.
The uncore units on Snow Ridge include Ubox, Chabox, IIO, IRP, M2PCIE,
PCU, M2M, PCIE3 and IMC.

- The config register encoding and pci device IDs are changed.
- For CHA, the umask_ext and filter_tid fields are changed.
- For IIO, the ch_mask and fc_mask fields are changed.
- For M2M, the mask_ext field is changed.
- Add new PCIe3 unit for PCIe3 root port which provides the interface
  between PCIe devices, plugged into the PCIe port, and the components
  (in M2IOSF).
- IMC can only be accessed via MMIO on Snow Ridge now. Current common
  code doesn't support it yet. IMC will be supported in following
  patches.
- There are 9 free running counters for IIO CLOCKS and bandwidth In.
- Full uncore event list is not published yet. Event constrain is not
  included in this patch. It will be added later separately.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: eranian@google.com
Link: https://lkml.kernel.org/r/1556672028-119221-3-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:18 +02:00
Kan Liang
543ac280b3 perf/x86/intel/uncore: Handle invalid event coding for free-running counter
Counting with invalid event coding for free-running counter may cause
OOPs, e.g. uncore_iio_free_running_0/event=1/.

Current code only validate the event with free-running event format,
event=0xff,umask=0xXY. Non-free-running event format never be checked
for the PMU with free-running counters.

Add generic hw_config() to check and reject the invalid event coding
for free-running PMU.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: eranian@google.com
Fixes: 0f519f0352 ("perf/x86/intel/uncore: Support IIO free-running counters on SKX")
Link: https://lkml.kernel.org/r/1556672028-119221-2-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:17 +02:00
Kan Liang
faaeff9866 perf/x86/intel: Add more Icelake CPUIDs
Add new model number for Icelake desktop and server to perf.

The data source encoding for Icelake server is the same as Skylake
server.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: qiuxu.zhuo@intel.com
Cc: rui.zhang@intel.com
Cc: tony.luck@intel.com
Link: https://lkml.kernel.org/r/20190603134122.13853-2-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:16 +02:00
Kan Liang
2a538fda82 perf/x86/intel: Add Icelake desktop CPUID
Add new Icelake desktop CPUID for RAPL, CSTATE and UNCORE.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: qiuxu.zhuo@intel.com
Cc: rui.zhang@intel.com
Cc: tony.luck@intel.com
Link: https://lkml.kernel.org/r/20190603134122.13853-3-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:36:14 +02:00
Rafael J. Wysocki
0c7376ada9 PCI: PM: Replace pci_dev_keep_suspended() with two functions
The code in pci_dev_keep_suspended() is relatively hard to follow due
to the negative checks in it and in its callers and the function has
a possible side-effect (disabling the PME) which doesn't really match
its role.

For this reason, move the PME disabling from pci_dev_keep_suspended()
to a separate function and change the semantics (and name) of the
rest of it, so that 'true' is returned when the device needs to be
resumed (and not the other way around).  Change the callers of
pci_dev_keep_suspended() accordingly.

While at it, make the code flow in pci_pm_poweroff() reflect the
pci_pm_suspend() more closely to avoid arbitrary differences between
them.

This is a cosmetic change with no intention to alter behavior.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2019-06-17 12:30:24 +02:00
Rafael J. Wysocki
234f223d63 PCI: PM: Avoid resuming devices in D3hot during system suspend
The current code resumes devices in D3hot during system suspend if
the target power state for them is D3cold, but that is not necessary
in general.  It only is necessary to do that if the platform firmware
requires the device to be resumed, but that should be covered by
the platform_pci_need_resume() check anyway, so rework
pci_dev_keep_suspended() to avoid returning 'false' for devices
in D3hot which need not be resumed due to platform firmware
requirements.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2019-06-17 12:30:24 +02:00
Ingo Molnar
bddb363673 Merge branch 'x86/cpu' into perf/core, to pick up dependent changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:29:16 +02:00
Waiman Long
a15ea1a35f locking/rwsem: Guard against making count negative
The upper bits of the count field is used as reader count. When
sufficient number of active readers are present, the most significant
bit will be set and the count becomes negative. If the number of active
readers keep on piling up, we may eventually overflow the reader counts.
This is not likely to happen unless the number of bits reserved for
reader count is reduced because those bits are need for other purpose.

To prevent this count overflow from happening, the most significant
bit is now treated as a guard bit (RWSEM_FLAG_READFAIL). Read-lock
attempts will now fail for both the fast and slow paths whenever this
bit is set. So all those extra readers will be put to sleep in the wait
list. Wakeup will not happen until the reader count reaches 0.

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: huang ying <huang.ying.caritas@gmail.com>
Link: https://lkml.kernel.org/r/20190520205918.22251-17-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:28:11 +02:00