The function_graph_enter() function does the work of calling the function
graph hook function and the management of the shadow stack, simplifying the
work done in the architecture dependent prepare_ftrace_return().

Have parisc use the new code, and remove the shadow stack management as well as
having to set up the trace structure.

This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.

Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: stable@kernel.org
Fixes: 03274a3ffb449 ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

This reverts commit d27dfa13b9f77ae7e6ed09d70a0426ed26c1a8f9.

Unfortunately, this patch needs to be reverted.  We need the full sync
barrier and not the limited barrier provided by using an ordered store.
The sync ensures that all accesses and cache purge instructions that
follow the sync are performed after all such instructions prior the sync
instruction have completed executing.

The patch breaks the rwlock implementation in glibc.  This caused the
test-lock application in the libprelude testsuite to hang.  With the
change reverted, the test runs correctly and the libprelude package
builds successfully.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>

Pull parisc updates from Helge Deller:
 "Three small patches:

   - A boot fix for A500 machines, crash was caused by the new
     alternative patching code from this merge window (Dave)

   - Change __kernel_suseconds_t to match glibc on 64-bit parisc (Arnd)

   - Use constants instead of hard-coded numbers (me)"

* 'parisc-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix A500 boot crash
  parisc: Use LINUX_GATEWAY_SPACE constant in entry.S
  parisc64: change __kernel_suseconds_t to match glibc

Pull XArray conversion from Matthew Wilcox:
 "The XArray provides an improved interface to the radix tree data
  structure, providing locking as part of the API, specifying GFP flags
  at allocation time, eliminating preloading, less re-walking the tree,
  more efficient iterations and not exposing RCU-protected pointers to
  its users.

  This patch set

   1. Introduces the XArray implementation

   2. Converts the pagecache to use it

   3. Converts memremap to use it

  The page cache is the most complex and important user of the radix
  tree, so converting it was most important. Converting the memremap
  code removes the only other user of the multiorder code, which allows
  us to remove the radix tree code that supported it.

  I have 40+ followup patches to convert many other users of the radix
  tree over to the XArray, but I'd like to get this part in first. The
  other conversions haven't been in linux-next and aren't suitable for
  applying yet, but you can see them in the xarray-conv branch if you're
  interested"

* 'xarray' of git://git.infradead.org/users/willy/linux-dax: (90 commits)
  radix tree: Remove multiorder support
  radix tree test: Convert multiorder tests to XArray
  radix tree tests: Convert item_delete_rcu to XArray
  radix tree tests: Convert item_kill_tree to XArray
  radix tree tests: Move item_insert_order
  radix tree test suite: Remove multiorder benchmarking
  radix tree test suite: Remove __item_insert
  memremap: Convert to XArray
  xarray: Add range store functionality
  xarray: Move multiorder_check to in-kernel tests
  xarray: Move multiorder_shrink to kernel tests
  xarray: Move multiorder account test in-kernel
  radix tree test suite: Convert iteration test to XArray
  radix tree test suite: Convert tag_tagged_items to XArray
  radix tree: Remove radix_tree_clear_tags
  radix tree: Remove radix_tree_maybe_preload_order
  radix tree: Remove split/join code
  radix tree: Remove radix_tree_update_node_t
  page cache: Finish XArray conversion
  dax: Convert page fault handlers to XArray
  ...

Use and mention the predefined LINUX_GATEWAY_SPACE constant in the
various important code sections which deal with the gateway page.

Signed-off-by: Helge Deller <deller@gmx.de>

Pull parisc updates from Helge Deller:
 "Lots of small fixes and enhancements, most noteably:

   - Many TLB and cache flush optimizations (Dave)

   - Fixed HPMC/crash handler on 64-bit kernel (Dave and myself)

   - Added alternative infrastructre. The kernel now live-patches itself
     for various situations, e.g. replace SMP code when running on one
     CPU only or drop cache flushes when system has no cache installed.

   - vmlinuz now contains a full copy of the compressed vmlinux file.
     This simplifies debugging the currently booted kernel.

   - Unused driver removal (Christoph)

   - Reduced warnings of Dino PCI bridge when running in qemu

   - Removed gcc version check (Masahiro)"

* 'parisc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: (23 commits)
  parisc: Retrieve and display the PDC PAT capabilities
  parisc: Optimze cache flush algorithms
  parisc: Remove pte_inserted define
  parisc: Add PDC PAT cell_info() and pd_get_pdc_revisions() functions
  parisc: Drop two instructions from pte lookup code
  parisc: Use zdep for shlw macro on PA1.1 and PA2.0
  parisc: Add alternative coding infrastructure
  parisc: Include compressed vmlinux file in vmlinuz boot kernel
  extract-vmlinux: Check for uncompressed image as fallback
  parisc: Fix address in HPMC IVA
  parisc: Fix exported address of os_hpmc handler
  parisc: Fix map_pages() to not overwrite existing pte entries
  parisc: Purge TLB entries after updating page table entry and set page accessed flag in TLB handler
  parisc: Release spinlocks using ordered store
  parisc: Ratelimit dino stuck interrupt warnings
  parisc: dino: Utilize DINO_MASK_IRQ() macro
  parisc: Clean up crash header output
  parisc: Add SYSTEM_INFO and REGISTER TOC PAT functions
  parisc: Remove PTE load and fault check from L2_ptep macro
  parisc: Reorder TLB flush timing calculation
  ...

Pull dma mapping updates from Christoph Hellwig:
 "First batch of dma-mapping changes for 4.20.

  There will be a second PR as some big changes were only applied just
  before the end of the merge window, and I want to give them a few more
  days in linux-next.

  Summary:

   - mostly more consolidation of the direct mapping code, including
     converting over hexagon, and merging the coherent and non-coherent
     code into a single dma_map_ops instance (me)

   - cleanups for the dma_configure/dma_unconfigure callchains (me)

   - better handling of dma_masks in odd setups (me, Alexander Duyck)

   - better debugging of passing vmalloc address to the DMA API (Stephen
     Boyd)

   - CMA command line parsing fix (He Zhe)"

* tag 'dma-mapping-4.20' of git://git.infradead.org/users/hch/dma-mapping: (27 commits)
  dma-direct: respect DMA_ATTR_NO_WARN
  dma-mapping: translate __GFP_NOFAIL to DMA_ATTR_NO_WARN
  dma-direct: document the zone selection logic
  dma-debug: Check for drivers mapping invalid addresses in dma_map_single()
  dma-direct: fix return value of dma_direct_supported
  dma-mapping: move dma_default_get_required_mask under ifdef
  dma-direct: always allow dma mask <= physiscal memory size
  dma-direct: implement complete bus_dma_mask handling
  dma-direct: refine dma_direct_alloc zone selection
  dma-direct: add an explicit dma_direct_get_required_mask
  dma-mapping: make the get_required_mask method available unconditionally
  unicore32: remove swiotlb support
  Revert "dma-mapping: clear dev->dma_ops in arch_teardown_dma_ops"
  dma-mapping: support non-coherent devices in dma_common_get_sgtable
  dma-mapping: consolidate the dma mmap implementations
  dma-mapping: merge direct and noncoherent ops
  dma-mapping: move the dma_coherent flag to struct device
  MIPS: don't select DMA_MAYBE_COHERENT from DMA_PERDEV_COHERENT
  dma-mapping: add the missing ARCH_HAS_SYNC_DMA_FOR_CPU_ALL declaration
  dma-mapping: fix panic caused by passing empty cma command line argument
  ...

Signed-off-by: Helge Deller <deller@gmx.de>

The attached patch implements three optimizations:

1) Loops in flush_user_dcache_range_asm, flush_kernel_dcache_range_asm,
purge_kernel_dcache_range_asm, flush_user_icache_range_asm, and
flush_kernel_icache_range_asm are unrolled to reduce branch overhead.

2) The static branch prediction for cmpb instructions in pacache.S have
been reviewed and the operand order adjusted where necessary.

3) For flush routines in cache.c, we purge rather flush when we have no
context.  The pdc instruction at level 0 is not required to write back
dirty lines to memory. This provides a performance improvement over the
fdc instruction if the feature is implemented.

Version 2 adds alternative patching.

The patch provides an average improvement of about 2%.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>

Add wrappers for the PDC_PAT_CELL_GET_INFO and
PDC_PAT_PD_GET_PDC_INTERF_REV PAT PDC subfunctions.

Both provide access to the PAT capability bitfield which can guide us if
simultaneous PTLBs are allowed on the bus, and if firmware will
rendezvous all processors within PDCE_Check in case of an HPMC.

Signed-off-by: Helge Deller <deller@gmx.de>