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  1. 19 5月, 2015 1 次提交
  3. 11 5月, 2015 1 次提交
  5. 13 10月, 2014 1 次提交
  7. 04 9月, 2014 1 次提交
  9. 30 8月, 2014 1 次提交
  11. 23 7月, 2014 3 次提交
  13. 26 6月, 2014 1 次提交
    • V
      ARC: [SMP] Enable icache coherency · 2328af0c
      由 Vineet Gupta 提交于 
      icaches are not snooped hence not cohrent in SMP setups which means
kernel has to do cross core calls to ensure the same.

The leaf routine __ic_line_inv_vaddr() now does cross core calls.

__sync_icache_dcache() is affected due to this:

* local dcache line flushed ahead of remote icache inv requests
* can't disable interrupts anymore, since
      __ic_line_inv_vaddr()->on_each_cpu() can deadlock.

| WARNING: CPU: 0 PID: 1 at kernel/smp.c:374
| smp_call_function_many+0x25a/0x2c4()
|
|  init_kprobes+0x90/0xc8
|     register_kprobe+0x1d6/0x510
|	__sync_icache_dcache+0x28/0x80
|
|	    DISABLE IRQ
|
|	    __ic_line_inv_vaddr
|		on_each_cpu
|		     smp_call_function_many+0x25a/0x2c4   --> WARN
|			__ic_line_inv_vaddr_local
|	    __dc_line_op

* TODO: Needs to use mask of relevant CPUs to avoid broadcasting
Signed-off-by: NNoam Camus <noamc@ezchip.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      2328af0c
  15. 03 6月, 2014 1 次提交
  17. 05 5月, 2014 1 次提交
  19. 05 4月, 2014 1 次提交
    • V
      ARC: [SMP] General Fixes · c3441edd
      由 Vineet Gupta 提交于 
      -Pass the expected arg to non-boot park'ing routine
 (It worked so far because existing SMP backends don't use the arg)

-CONFIG_DEBUG_PREEMPT warning
      c3441edd
  21. 08 3月, 2014 1 次提交
  23. 06 11月, 2013 4 次提交
  25. 29 8月, 2013 1 次提交
  27. 27 6月, 2013 1 次提交
    • P
      arc: delete __cpuinit usage from all arc files · ce759956
      由 Paul Gortmaker 提交于 
      The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/arc uses of the __cpuinit macros from
all C files.  Currently arc does not have any __CPUINIT used in
assembly files.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      ce759956
  29. 22 6月, 2013 7 次提交
  31. 25 5月, 2013 1 次提交
    • V
      ARC: lazy dcache flush broke gdb in non-aliasing configs · 7bb66f6e
      由 Vineet Gupta 提交于 
      gdbserver inserting a breakpoint ends up calling copy_user_page() for a
code page. The generic version of which (non-aliasing config) didn't set
the PG_arch_1 bit hence update_mmu_cache() didn't sync dcache/icache for
corresponding dynamic loader code page - causing garbade to be executed.

So now aliasing versions of copy_user_highpage()/clear_page() are made
default. There is no significant overhead since all of special alias
handling code is compiled out for non-aliasing build
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      7bb66f6e
  33. 23 5月, 2013 1 次提交
  35. 10 5月, 2013 3 次提交
    • V
      ARC: [mm] Aliasing VIPT dcache support 3/4 · de2a852c
      由 Vineet Gupta 提交于 
      Fix the one zillion warnings
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      de2a852c
    • V
      ARC: [mm] Aliasing VIPT dcache support 2/4 · 4102b533
      由 Vineet Gupta 提交于 
      This is the meat of the series which prevents any dcache alias creation
by always keeping the U and K mapping of a page congruent.
If a mapping already exists, and other tries to access the page, prev
one is flushed to physical page (wback+inv)

Essentially flush_dcache_page()/copy_user_highpage() create K-mapping
of a page, but try to defer flushing, unless U-mapping exist.
When page is actually mapped to userspace, update_mmu_cache() flushes
the K-mapping (in certain cases this can be optimised out)

Additonally flush_cache_mm(), flush_cache_range(), flush_cache_page()
handle the puring of stale userspace mappings on exit/munmap...

flush_anon_page() handles the existing U-mapping for anon page before
kernel reads it via the GUP path.

Note that while not complete, this is enough to boot a simple
dynamically linked Busybox based rootfs
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      4102b533
    • V
      ARC: [mm] Aliasing VIPT dcache support 1/4 · 6ec18a81
      由 Vineet Gupta 提交于 
      This preps the low level dcache flush helpers to take vaddr argument in
addition to the existing paddr to properly flush the VIPT dcache
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      6ec18a81
  37. 09 5月, 2013 2 次提交
  39. 07 5月, 2013 6 次提交
    • V
      ARC: [mm] Lazy D-cache flush (non aliasing VIPT) · eacd0e95
      由 Vineet Gupta 提交于 
      flush_dcache_page( ) is MM hook to ensure that a page has consistent
views between kernel and userspace. Thus it is called when

* kernel writes to a page which at some later point could get mapped to
  userspace (so kernel mapping needs to be flushed-n-inv)
* kernel is about to read from a page with possible userspace mappings
  (so userspace mappings needs to be made coherent with kernel ones)

However for Non aliasing VIPT dcache, any userspace mapping will always
be congruent to kernel mapping. Thus d-cache need need not be flushed at
all (or delayed indefinitely).

The only reason it does need to be flushed is when mapping code pages.
Since icache doesn't snoop dcache, those dirty dcache lines need to be
written back to memory and icache line invalidated so that icache lines
fetch will get the right data.

Decent gains on LMBench fork/exec/sh and File I/O micro-benchmarks.

(1) FPGA @ 80 MHZ

Processor, Processes - times in microseconds - smaller is better
------------------------------------------------------------------------------
Host                 OS  Mhz null null      open slct sig  sig  fork exec sh
                             call  I/O stat clos TCP  inst hndl proc proc proc
--------- ------------- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
3.9-rc6-a Linux 3.9.0-r   80 4.79 8.72 66.7 116. 239. 8.39 30.4 4798 14.K 34.K
3.9-rc6-b Linux 3.9.0-r   80 4.79 8.62 65.4 111. 239. 8.35 29.0 3995 12.K 30.K
3.9-rc7-c Linux 3.9.0-r   80 4.79 9.00 66.1 106. 239. 8.61 30.4 2858 10.K 24.K
                                                                ^^^^ ^^^^ ^^^

File & VM system latencies in microseconds - smaller is better
-------------------------------------------------------------------------------
Host                 OS   0K File      10K File     Mmap    Prot   Page 100fd
                        Create Delete Create Delete Latency Fault  Fault selct
--------- ------------- ------ ------ ------ ------ ------- ----- ------- -----
3.9-rc6-a Linux 3.9.0-r  317.8  204.2 1122.3  375.1 3522.0 4.288     20.7 126.8
3.9-rc6-b Linux 3.9.0-r  298.7  223.0 1141.6  367.8 3531.0 4.866     20.9 126.4
3.9-rc7-c Linux 3.9.0-r  278.4  179.2  862.1  339.3 3705.0 3.223     20.3 126.6
                         ^^^^^  ^^^^^  ^^^^^  ^^^^

(2) Customer Silicon @ 500 MHz (166 MHz mem)

------------------------------------------------------------------------------
Host                 OS  Mhz null null      open slct sig  sig  fork exec sh
                             call  I/O stat clos TCP  inst hndl proc proc proc
--------- ------------- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
abilis-ba Linux 3.9.0-r  497 0.71 1.38 4.58 12.0 35.5 1.40 3.89 2070 5525 13.K
abilis-ca Linux 3.9.0-r  497 0.71 1.40 4.61 11.8 35.6 1.37 3.92 1411 4317 10.K
                                                                ^^^^ ^^^^ ^^^
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      eacd0e95
    • V
      ARC: [mm] micro-optimize page size icache invalidate · 764531cc
      由 Vineet Gupta 提交于 
      start address is already page aligned and size is const PAGE_SIZE,
thus fixups for alignment not needed in generated code.

bloat-o-meter vmlinux-mm5 vmlinux
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-32 (-32)
function                                     old     new   delta
__inv_icache_page                             82      50     -32
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      764531cc
    • V
      ARC: [mm] remove the pessimistic all-alias-invalidate icache helpers · 7f250a0f
      由 Vineet Gupta 提交于 
      No users of this code anymore - so RIP !
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      7f250a0f
    • V
      ARC: [mm] consolidate icache/dcache sync code · 94bad1af
      由 Vineet Gupta 提交于 
      Now that we have same helper used for all icache invalidates (i.e.
vaddr+paddr based exact line invalidate), consolidate the open coded
calls into one place.

Also rename flush_icache_range_vaddr => __sync_icache_dcache
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      94bad1af
    • V
      ARC: [mm] optimise icache flush for kernel mappings · 7586bf72
      由 Vineet Gupta 提交于 
      This change continues the theme from prev commit - this time icache
handling for kernel's own code modification (vmalloc: loadable modules,
breakpoints for kprobes/kgdb...)

flush_icache_range() calls the CDU icache helper with vaddr to enable
exact line invalidate.

For a true kernel-virtual mapping, the vaddr is actually virtual hence
valid as index into cache. For kprobes breakpoint however, the vaddr arg
is actually paddr - since that's how normal kernel is mapped in ARC
memory map.  This implies that CDU will use the same addr for
indexing as for tag match - which is fine since kernel code would only
have that "implicit" mapping and none other.

This should speed up module loading significantly - specially on default
ARC700 icache configurations (32k) which alias.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      7586bf72
    • V
      ARC: [mm] optimise icache flush for user mappings · 24603fdd
      由 Vineet Gupta 提交于 
      ARC icache doesn't snoop dcache thus executable pages need to be made
coherent before mapping into userspace in flush_icache_page().

However ARC700 CDU (hardware cache flush module) requires both vaddr
(index in cache) as well as paddr (tag match) to correctly identify a
line in the VIPT cache. A typical ARC700 SoC has aliasing icache, thus
the paddr only based flush_icache_page() API couldn't be implemented
efficiently. It had to loop thru all possible alias indexes and perform
the invalidate operation (ofcourse the cache op would only succeed at
the index(es) where tag matches - typically only 1, but the cost of
visiting all the cache-bins needs to paid nevertheless).

Turns out however that the vaddr (along with paddr) is available in
update_mmu_cache() hence better suits ARC icache flush semantics.
With both vaddr+paddr, exactly one flush operation per line is done.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
      24603fdd
  41. 09 4月, 2013 1 次提交