Commit Graph

16 Commits

Author SHA1 Message Date
Chris Metcalf 893d66192c tile: support gcc 7 optimization to use __multi3
The tip gcc includes an optimization mode that converts
64-bit divides into 128-bit multiplies using __multi3.
Export the symbol so that modules can find it.  We just
export unconditionally without worrying about the gcc
version, since the symbol has been in libgcc forever and
the function is less than 300 bytes.

Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
2016-06-24 15:32:02 -04:00
Chris Metcalf 47ad7b9bbe tile: improve stack backtrace
This commit fixes a number of issues with the tile backtrace code.

- Don't try to identify userspace shared object or executable paths
  if we are doing a backtrace from an interrupt; it's not legal,
  and also unlikely to be interesting.  Likewise, don't try to do
  it for other address spaces, since d_path() assumes it is being
  called in "current" context.

- Move "in_backtrace" from thread_struct to thread_info.
  This way we can access it even if our stack thread_info has been
  clobbered, which makes backtracing more robust.

- Avoid using "current" directly when testing for is_sigreturn().
  Since "current" may be corrupt, we're better off using kbt->task
  explicitly to look up the vdso_base for the current task.
  Conveniently, this simplifies the internal APIs (we only need
  one is_sigreturn() function now).

- Avoid bogus "Odd fault" warning when pc/sp/ex1 are all zero,
  as is true for kernel threads above the last frame.

- Hook into Tejun Heo's dump_stack() framework in lib/dump_stack.c.

- Write last entry in save_stack_trace() as ULONG_MAX, not zero,
  since ftrace (at least) relies on finding that marker.

- Implement save_stack_trace_regs() and save_strack_trace_user(),
  and set CONFIG_USER_STACKTRACE_SUPPORT.

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
2015-05-11 11:22:40 -04:00
Chris Metcalf 5bf6c07a18 tile: add <asm/word-at-a-time.h> and enable support functions
This change enables the generic strncpy_from_user() and strnlen_user()
using word-at-a-time.h.  The tile implementation is trivial since
both tilepro and tilegx have SIMD operations that do byte-wise
comparisons against immediate zero for each byte, and return an
0x01 byte in each position where there is a 0x00 byte.

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
2015-04-30 15:23:37 -04:00
Tony Lu a61fd5e366 tile: support ftrace on tilegx
This commit adds support for static ftrace, graph function support,
and dynamic tracer support.

Signed-off-by: Tony Lu <zlu@tilera.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30 10:20:13 -04:00
Chris Metcalf dd78bc11fb tile: convert uses of "inv" to "finv"
The "inv" (invalidate) instruction is generally less safe than "finv"
(flush and invalidate), as it will drop dirty data from the cache.
It turns out we have almost no need for "inv" (other than for the
older 32-bit architecture in some limited cases), so convert to
"finv" where possible and delete the extra "inv" infrastructure.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-07-31 11:51:19 -04:00
Chris Metcalf 3cb3f839d3 tilepro: work around module link error with gcc 4.7
gcc 4.7.x is emitting calls to __ffsdi2 where previously
it used to inline the appropriate ctz instructions.
While this needs to be fixed in gcc, it's also easy to avoid
having it cause build failures when building with those
compilers by exporting __ffsdi2 to modules.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: stable@kernel.org
2013-06-15 16:47:47 -04:00
Chris Metcalf 7c63e1ee0a tile: export a handful of symbols appropriately
This was shown up by running with "allmodconfig".  I used
EXPORT_SYMBOL() to match existing conventions in files that
were already exporting symbols, or that were exported that way
by other architectures, and otherwise EXPORT_SYMBOL_GPL().

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-02-08 13:20:36 -05:00
Chris Metcalf 47d632f9f8 arch/tile: optimize get_user/put_user and friends
Use direct load/store for the get_user/put_user.

Previously, we would call out to a helper routine that would do the
appropriate thing and then return, handling the possible exception
internally.  Now we inline the load or store, along with a "we succeeded"
indication in a register; if the load or store faults, we write a
"we failed" indication into the same register and then return to the
following instruction.  This is more efficient and gives us more compact
code, as well as being more in line with what other architectures do.

The special futex assembly source file for TILE-Gx also disappears in
this change; we just use the same inlining idiom there as well, putting
the appropriate atomic operations directly into futex_atomic_op_inuser()
(and thus into the FUTEX_WAIT function).

The underlying atomic copy_from_user, copy_to_user functions were
renamed using the (cryptic) x86 convention as copy_from_user_ll and
copy_to_user_ll.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-05-25 12:48:23 -04:00
Chris Metcalf 3989efb770 arch/tile: add a few #includes and an EXPORT to catch up with kernel changes.
The empty_zero_page[] export is required for ZERO_PAGE() module references.
The #includes are due to changes in implicit inclusion, and should of
course have been in the sources from the beginning.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-12-03 15:31:41 -05:00
Chris Metcalf f319d6e238 arch/tile: avoid exporting a symbol no longer used by gcc
An earlier Tilera compiler generated calls to an "__ll_mul"
function for long long multiplication.  Our libgcc supported that
as an alias for the normal __muldi3 routine, so we made it available
to kernel modules as well.  However, for a while now the compiler
has internally been generating only the standard __muldi3 symbol,
and the version we are giving back to the community does not have
the __ll_mul alias, so we are removing it from the kernel too.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-11-03 16:58:42 -04:00
Chris Metcalf 00dce03134 arch/tile: export some additional module symbols
This adds a grab bag of symbols that have been missing for
various modules.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-03-01 16:21:12 -05:00
Chris Metcalf 6c4d112688 arch/tile: use extended assembly to inline __mb_incoherent()
This avoids having to maintain an additional separate assembly
file, and of course the inline is slightly more efficient as well.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-03-01 16:20:54 -05:00
Chris Metcalf 13c9d5a630 arch/tile: properly export __mb_incoherent for modules
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-10-14 15:12:55 -04:00
Chris Metcalf c745a8a11f arch/tile: Various cleanups.
This change rolls up random cleanups not representing any actual bugs.

- Remove a stale CONFIG_ value from the default tile_defconfig
- Remove unused tns_atomic_xxx() family of methods from <asm/atomic.h>
- Optimize get_order() using Tile's "clz" instruction
- Fix a bad hypervisor upcall name (not currently used in Linux anyway)
- Use __copy_in_user_inatomic() name for consistency, and export it
- Export some additional hypervisor driver I/O upcalls and some homecache calls
- Remove the obfuscating MEMCPY_TEST_WH64 support code
- Other stray comment cleanups, #if 0 removal, etc.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2010-08-13 08:52:19 -04:00
Chris Metcalf 0707ad30d1 arch/tile: Miscellaneous cleanup changes.
This commit is primarily changes caused by reviewing "sparse"
and "checkpatch" output on our sources, so is somewhat noisy, since
things like "printk() -> pr_err()" (or whatever) throughout the
codebase tend to get tedious to read.  Rather than trying to tease
apart precisely which things changed due to which type of code
review, this commit includes various cleanups in the code:

- sparse: Add declarations in headers for globals.
- sparse: Fix __user annotations.
- sparse: Using gfp_t consistently instead of int.
- sparse: removing functions not actually used.
- checkpatch: Clean up printk() warnings by using pr_info(), etc.;
  also avoid partial-line printks except in bootup code.
  - checkpatch: Use exposed structs rather than typedefs.
  - checkpatch: Change some C99 comments to C89 comments.

In addition, a couple of minor other changes are rolled in
to this commit:

- Add support for a "raise" instruction to cause SIGFPE, etc., to be raised.
- Remove some compat code that is unnecessary when we fully eliminate
  some of the deprecated syscalls from the generic syscall ABI.
- Update the tile_defconfig to reflect current config contents.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2010-07-06 13:41:51 -04:00
Chris Metcalf 867e359b97 arch/tile: core support for Tilera 32-bit chips.
This change is the core kernel support for TILEPro and TILE64 chips.
No driver support (except the console driver) is included yet.

This includes the relevant Linux headers in asm/; the low-level
low-level "Tile architecture" headers in arch/, which are
shared with the hypervisor, etc., and are build-system agnostic;
and the relevant hypervisor headers in hv/.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Paul Mundt <lethal@linux-sh.org>
2010-06-04 17:11:18 -04:00