linux-stable.git/arch/powerpc/sysdev/xive, branch v5.13.2

Merge branch 'akpm' (patches from Andrew)

2021-04-30T21:38:01+00:00

Merge misc updates from Andrew Morton:
 "A few misc subsystems and some of MM.

  175 patches.

  Subsystems affected by this patch series: ia64, kbuild, scripts, sh,
  ocfs2, kfifo, vfs, kernel/watchdog, and mm (slab-generic, slub,
  kmemleak, debug, pagecache, msync, gup, memremap, memcg, pagemap,
  mremap, dma, sparsemem, vmalloc, documentation, kasan, initialization,
  pagealloc, and memory-failure)"

* emailed patches from Andrew Morton : (175 commits)
  mm/memory-failure: unnecessary amount of unmapping
  mm/mmzone.h: fix existing kernel-doc comments and link them to core-api
  mm: page_alloc: ignore init_on_free=1 for debug_pagealloc=1
  net: page_pool: use alloc_pages_bulk in refill code path
  net: page_pool: refactor dma_map into own function page_pool_dma_map
  SUNRPC: refresh rq_pages using a bulk page allocator
  SUNRPC: set rq_page_end differently
  mm/page_alloc: inline __rmqueue_pcplist
  mm/page_alloc: optimize code layout for __alloc_pages_bulk
  mm/page_alloc: add an array-based interface to the bulk page allocator
  mm/page_alloc: add a bulk page allocator
  mm/page_alloc: rename alloced to allocated
  mm/page_alloc: duplicate include linux/vmalloc.h
  mm, page_alloc: avoid page_to_pfn() in move_freepages()
  mm/Kconfig: remove default DISCONTIGMEM_MANUAL
  mm: page_alloc: dump migrate-failed pages
  mm/mempolicy: fix mpol_misplaced kernel-doc
  mm/mempolicy: rewrite alloc_pages_vma documentation
  mm/mempolicy: rewrite alloc_pages documentation
  mm/mempolicy: rename alloc_pages_current to alloc_pages
  ...

powerpc/xive: remove unnecessary unmap_kernel_range

2021-04-30T18:20:40+00:00

iounmap will remove ptes.

Link: https://lkml.kernel.org/r/20210322021806.892164-4-npiggin@gmail.com
Signed-off-by: Nicholas Piggin 
Reviewed-by: Christoph Hellwig 
Acked-by: Cédric Le Goater 
Cc: Uladzislau Rezki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

powerpc/xive: Use the "ibm, chip-id" property only under PowerNV

2021-04-17T00:40:51+00:00

The 'chip_id' field of the XIVE CPU structure is used to choose a
target for a source located on the same chip. For that, the XIVE
driver queries the chip identifier from the "ibm,chip-id" property
and compares it to a 'src_chip' field identifying the chip of a
source. This information is only available on the PowerNV platform,
'src_chip' being assigned to XIVE_INVALID_CHIP_ID under pSeries.

The "ibm,chip-id" property is also not available on all platforms. It
was first introduced on PowerNV and later, under QEMU for pSeries/KVM.
However, the property is not part of PAPR and does not exist under
pSeries/PowerVM.

Assign 'chip_id' to XIVE_INVALID_CHIP_ID by default and let the
PowerNV platform override the value with the "ibm,chip-id" property.

Signed-off-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210413130352.1183267-1-clg@kaod.org

powerpc/xive: Modernize XIVE-IPI domain with an 'alloc' handler

2021-04-14T13:04:15+00:00

Instead of calling irq_create_mapping() to map the IPI for a node,
introduce an 'alloc' handler. This is usually an extension to support
hierarchy irq_domains which is not exactly the case for XIVE-IPI
domain. However, we can now use the irq_domain_alloc_irqs() routine
which allocates the IRQ descriptor on the specified node, even better
for cache performance on multi node machines.

Signed-off-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-10-clg@kaod.org

powerpc/xive: Map one IPI interrupt per node

2021-04-14T13:04:15+00:00

ipistorm [*] can be used to benchmark the raw interrupt rate of an
interrupt controller by measuring the number of IPIs a system can
sustain. When applied to the XIVE interrupt controller of POWER9 and
POWER10 systems, a significant drop of the interrupt rate can be
observed when crossing the second node boundary.

This is due to the fact that a single IPI interrupt is used for all
CPUs of the system. The structure is shared and the cache line updates
impact greatly the traffic between nodes and the overall IPI
performance.

As a workaround, the impact can be reduced by deactivating the IRQ
lockup detector ("noirqdebug") which does a lot of accounting in the
Linux IRQ descriptor structure and is responsible for most of the
performance penalty.

As a fix, this proposal allocates an IPI interrupt per node, to be
shared by all CPUs of that node. It solves the scaling issue, the IRQ
lockup detector still has an impact but the XIVE interrupt rate scales
linearly. It also improves the "noirqdebug" case as showed in the
tables below.

 * P9 DD2.2 - 2s * 64 threads

                                               "noirqdebug"
                        Mint/s                    Mint/s
 chips  cpus      IPI/sys   IPI/chip       IPI/chip    IPI/sys
 --------------------------------------------------------------
 1      0-15     4.984023   4.875405       4.996536   5.048892
        0-31    10.879164  10.544040      10.757632  11.037859
        0-47    15.345301  14.688764      14.926520  15.310053
        0-63    17.064907  17.066812      17.613416  17.874511
 2      0-79    11.768764  21.650749      22.689120  22.566508
        0-95    10.616812  26.878789      28.434703  28.320324
        0-111   10.151693  31.397803      31.771773  32.388122
        0-127    9.948502  33.139336      34.875716  35.224548

 * P10 DD1 - 4s (not homogeneous) 352 threads

                                               "noirqdebug"
                        Mint/s                    Mint/s
 chips  cpus      IPI/sys   IPI/chip       IPI/chip    IPI/sys
 --------------------------------------------------------------
 1      0-15     2.409402   2.364108       2.383303   2.395091
        0-31     6.028325   6.046075       6.089999   6.073750
        0-47     8.655178   8.644531       8.712830   8.724702
        0-63    11.629652  11.735953      12.088203  12.055979
        0-79    14.392321  14.729959      14.986701  14.973073
        0-95    12.604158  13.004034      17.528748  17.568095
 2      0-111    9.767753  13.719831      19.968606  20.024218
        0-127    6.744566  16.418854      22.898066  22.995110
        0-143    6.005699  19.174421      25.425622  25.417541
        0-159    5.649719  21.938836      27.952662  28.059603
        0-175    5.441410  24.109484      31.133915  31.127996
 3      0-191    5.318341  24.405322      33.999221  33.775354
        0-207    5.191382  26.449769      36.050161  35.867307
        0-223    5.102790  29.356943      39.544135  39.508169
        0-239    5.035295  31.933051      42.135075  42.071975
        0-255    4.969209  34.477367      44.655395  44.757074
 4      0-271    4.907652  35.887016      47.080545  47.318537
        0-287    4.839581  38.076137      50.464307  50.636219
        0-303    4.786031  40.881319      53.478684  53.310759
        0-319    4.743750  43.448424      56.388102  55.973969
        0-335    4.709936  45.623532      59.400930  58.926857
        0-351    4.681413  45.646151      62.035804  61.830057

[*] https://github.com/antonblanchard/ipistorm

Signed-off-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-9-clg@kaod.org

powerpc/xive: Fix xmon command "dxi"

2021-04-14T13:04:15+00:00

When under xmon, the "dxi" command dumps the state of the XIVE
interrupts. If an interrupt number is specified, only the state of
the associated XIVE interrupt is dumped. This form of the command
lacks an irq_data parameter which is nevertheless used by
xmon_xive_get_irq_config(), leading to an xmon crash.

Fix that by doing a lookup in the system IRQ mapping to query the IRQ
descriptor data. Invalid interrupt numbers, or not belonging to the
XIVE IRQ domain, OPAL event interrupt number for instance, should be
caught by the previous query done at the firmware level.

Fixes: 97ef27507793 ("powerpc/xive: Fix xmon support on the PowerNV platform")
Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Cédric Le Goater 
Tested-by: Greg Kurz 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-8-clg@kaod.org

powerpc/xive: Simplify the dump of XIVE interrupts under xmon

2021-04-14T13:04:14+00:00

Move the xmon routine under XIVE subsystem and rework the loop on the
interrupts taking into account the xive_irq_domain to filter out IPIs.

Signed-off-by: Cédric Le Goater 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-7-clg@kaod.org

powerpc/xive: Drop check on irq_data in xive_core_debug_show()

2021-04-14T13:04:14+00:00

When looping on IRQ descriptor, irq_data is always valid.

Fixes: 930914b7d528 ("powerpc/xive: Add a debugfs file to dump internal XIVE state")
Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Cédric Le Goater 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-6-clg@kaod.org

powerpc/xive: Simplify xive_core_debug_show()

2021-04-14T13:04:14+00:00

Now that the IPI interrupt has its own domain, the checks on the HW
interrupt number XIVE_IPI_HW_IRQ and on the chip can be replaced by a
check on the domain.

Signed-off-by: Cédric Le Goater 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-5-clg@kaod.org

powerpc/xive: Remove useless check on XIVE_IPI_HW_IRQ

2021-04-14T13:04:14+00:00

The IPI interrupt has its own domain now. Testing the HW interrupt
number is not needed anymore.

Signed-off-by: Cédric Le Goater 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-4-clg@kaod.org