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  1. 02 6月, 2017 18 次提交
    • M
      powerpc/lib/xor_vmx: Ensure no altivec code executes before enable_kernel_altivec() · f718d426
      由 Matt Brown 提交于 
      The xor_vmx.c file is used for the RAID5 xor operations. In these functions
altivec is enabled to run the operation and then disabled.

The code uses enable_kernel_altivec() around the core of the algorithm, however
the whole file is built with -maltivec, so the compiler is within its rights to
generate altivec code anywhere. This has been seen at least once in the wild:

  0:mon> di $xor_altivec_2
  c0000000000b97d0  3c4c01d9	addis   r2,r12,473
  c0000000000b97d4  3842db30	addi    r2,r2,-9424
  c0000000000b97d8  7c0802a6	mflr    r0
  c0000000000b97dc  f8010010	std     r0,16(r1)
  c0000000000b97e0  60000000	nop
  c0000000000b97e4  7c0802a6	mflr    r0
  c0000000000b97e8  faa1ffa8	std     r21,-88(r1)
  ...
  c0000000000b981c  f821ff41	stdu    r1,-192(r1)
  c0000000000b9820  7f8101ce	stvx    v28,r1,r0		<-- POP
  c0000000000b9824  38000030	li      r0,48
  c0000000000b9828  7fa101ce	stvx    v29,r1,r0
  ...
  c0000000000b984c  4bf6a06d	bl      c0000000000238b8 # enable_kernel_altivec

This patch splits the non-altivec code into xor_vmx_glue.c which calls the
altivec functions in xor_vmx.c. By compiling xor_vmx_glue.c without
-maltivec we can guarantee that altivec instruction will not be executed
outside of the enable/disable block.
Signed-off-by: NMatt Brown <matthew.brown.dev@gmail.com>
[mpe: Rework change log and include disassembly]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      f718d426
    • H
      powerpc/fadump: Set an upper limit for boot memory size · 48a316e3
      由 Hari Bathini 提交于 
      By default, 5% of system RAM is reserved for preserving boot memory.
Alternatively, a user can specify the amount of memory to reserve.
See Documentation/powerpc/firmware-assisted-dump.txt for details. In
addition to the memory reserved for preserving boot memory, some more
memory is reserved, to save HPTE region, CPU state data and ELF core
headers.

Memory Reservation during first kernel looks like below:

  Low memory                                        Top of memory
  0      boot memory size                                       |
  |           |                       |<--Reserved dump area -->|
  V           V                       |   Permanent Reservation V
  +-----------+----------/ /----------+---+----+-----------+----+
  |           |                       |CPU|HPTE|  DUMP     |ELF |
  +-----------+----------/ /----------+---+----+-----------+----+
        |                                           ^
        |                                           |
        \                                           /
         -------------------------------------------
          Boot memory content gets transferred to
          reserved area by firmware at the time of
          crash

This implicitly means that the sum of the sizes of boot memory, CPU
state data, HPTE region, DUMP preserving area and ELF core headers
can't be greater than the total memory size. But currently, a user is
allowed to specify any value as boot memory size. So, the above rule
is violated when a boot memory size around 50% of the total available
memory is specified. As the kernel is not handling this currently, it
may lead to undefined behavior. Fix it by setting an upper limit for
boot memory size to 25% of the total available memory. Also, instead
of using memblock_end_of_DRAM(), which doesn't take the holes, if any,
in the memory layout into account, use memblock_phys_mem_size() to
calculate the percentage of total available memory.
Signed-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      48a316e3
    • H
      powerpc/fadump: Update comment about offset where fadump is reserved · e7467dc6
      由 Hari Bathini 提交于 
      With commit f6e6bedb ("powerpc/fadump: Reserve memory at an offset
closer to bottom of RAM"), memory for fadump is no longer reserved at
the top of RAM. But there are still a few places which say so. Change
them appropriately.
Signed-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      e7467dc6
    • H
      powerpc/fadump: Add a warning when 'fadump_reserve_mem=' is used · 81d9eca5
      由 Hari Bathini 提交于 
      With commit 11550dc0 ("powerpc/fadump: reuse crashkernel parameter
for fadump memory reservation"), 'fadump_reserve_mem=' parameter is
deprecated in favor of 'crashkernel=' parameter. Add a warning if
'fadump_reserve_mem=' is still used.

Fixes: 11550dc0 ("powerpc/fadump: reuse crashkernel parameter for fadump memory reservation")
Suggested-by: NPrarit Bhargava <prarit@redhat.com>
Signed-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com>
[mpe: Unsplit long printk strings]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      81d9eca5
    • M
      powerpc/fadump: Return error when fadump registration fails · 98b8cd7f
      由 Michal Suchanek 提交于 
       - log an error message when registration fails and no error code listed
   in the switch is returned
 - translate the hv error code to posix error code and return it from
   fw_register
 - return the posix error code from fw_register to the process writing
   to sysfs
 - return EEXIST on re-registration
 - return success on deregistration when fadump is not registered
 - return ENODEV when no memory is reserved for fadump
Signed-off-by: NMichal Suchanek <msuchanek@suse.de>
Tested-by: NHari Bathini <hbathini@linux.vnet.ibm.com>
[mpe: Use pr_err() to shrink the error print]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      98b8cd7f
    • C
      powerpc: Remove __ilog2()s and use generic ones · f782ddf2
      由 Christophe Leroy 提交于 
      With the __ilog2() function as defined in
arch/powerpc/include/asm/bitops.h, GCC will not optimise the code
in case of constant parameter.

The generic ilog2() function in include/linux/log2.h is written
to handle the case of the constant parameter.

This patch discards the three __ilog2() functions and
defines __ilog2() as ilog2()

For non constant calls, the generated code is doing the same:
int test__ilog2(unsigned long x)
{
	return __ilog2(x);
}

int test__ilog2_u32(u32 n)
{
	return __ilog2_u32(n);
}

int test__ilog2_u64(u64 n)
{
	return __ilog2_u64(n);
}

On PPC32 before the patch:
00000000 <test__ilog2>:
   0:	7c 63 00 34 	cntlzw  r3,r3
   4:	20 63 00 1f 	subfic  r3,r3,31
   8:	4e 80 00 20 	blr

0000000c <test__ilog2_u32>:
   c:	7c 63 00 34 	cntlzw  r3,r3
  10:	20 63 00 1f 	subfic  r3,r3,31
  14:	4e 80 00 20 	blr

On PPC32 after the patch:
00000000 <test__ilog2>:
   0:	7c 63 00 34 	cntlzw  r3,r3
   4:	20 63 00 1f 	subfic  r3,r3,31
   8:	4e 80 00 20 	blr

0000000c <test__ilog2_u32>:
   c:	7c 63 00 34 	cntlzw  r3,r3
  10:	20 63 00 1f 	subfic  r3,r3,31
  14:	4e 80 00 20 	blr

On PPC64 before the patch:
0000000000000000 <.test__ilog2>:
   0:	7c 63 00 74 	cntlzd  r3,r3
   4:	20 63 00 3f 	subfic  r3,r3,63
   8:	7c 63 07 b4 	extsw   r3,r3
   c:	4e 80 00 20 	blr

0000000000000010 <.test__ilog2_u32>:
  10:	7c 63 00 34 	cntlzw  r3,r3
  14:	20 63 00 1f 	subfic  r3,r3,31
  18:	7c 63 07 b4 	extsw   r3,r3
  1c:	4e 80 00 20 	blr

0000000000000020 <.test__ilog2_u64>:
  20:	7c 63 00 74 	cntlzd  r3,r3
  24:	20 63 00 3f 	subfic  r3,r3,63
  28:	7c 63 07 b4 	extsw   r3,r3
  2c:	4e 80 00 20 	blr

On PPC64 after the patch:
0000000000000000 <.test__ilog2>:
   0:	7c 63 00 74 	cntlzd  r3,r3
   4:	20 63 00 3f 	subfic  r3,r3,63
   8:	7c 63 07 b4 	extsw   r3,r3
   c:	4e 80 00 20 	blr

0000000000000010 <.test__ilog2_u32>:
  10:	7c 63 00 34 	cntlzw  r3,r3
  14:	20 63 00 1f 	subfic  r3,r3,31
  18:	7c 63 07 b4 	extsw   r3,r3
  1c:	4e 80 00 20 	blr

0000000000000020 <.test__ilog2_u64>:
  20:	7c 63 00 74 	cntlzd  r3,r3
  24:	20 63 00 3f 	subfic  r3,r3,63
  28:	7c 63 07 b4 	extsw   r3,r3
  2c:	4e 80 00 20 	blr
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      f782ddf2
    • C
      powerpc: Replace ffz() by equivalent generic function · 22ef33b3
      由 Christophe Leroy 提交于 
      With the ffz() function as defined in arch/powerpc/include/asm/bitops.h
GCC will not optimise the code in case of constant parameter.

This patch replaces ffz() by the generic function.

The generic ffz(x) expects to never be called with ~x == 0
as written in the comment in include/asm-generic/bitops/ffz.h
The only user of ffz() within arch/powerpc/ is
platforms/512x/mpc5121_ads_cpld.c, which checks if x is not 0xff

For non constant calls, the generated code is doing the same:

unsigned long testffz(unsigned long x)
{
	return ffz(x);
}

On PPC32, before the patch:
00000018 <testffz>:
  18:	7c 63 18 f9 	not.    r3,r3
  1c:	40 82 00 0c 	bne     28 <testffz+0x10>
  20:	38 60 00 20 	li      r3,32
  24:	4e 80 00 20 	blr
  28:	7d 23 00 d0 	neg     r9,r3
  2c:	7d 23 18 38 	and     r3,r9,r3
  30:	7c 63 00 34 	cntlzw  r3,r3
  34:	20 63 00 1f 	subfic  r3,r3,31
  38:	4e 80 00 20 	blr

On PPC32, after the patch:
00000018 <testffz>:
  18:	39 23 00 01 	addi    r9,r3,1
  1c:	7d 23 18 78 	andc    r3,r9,r3
  20:	7c 63 00 34 	cntlzw  r3,r3
  24:	20 63 00 1f 	subfic  r3,r3,31
  28:	4e 80 00 20 	blr

On PPC64, before the patch:
0000000000000030 <.testffz>:
  30:	7c 60 18 f9 	not.    r0,r3
  34:	38 60 00 40 	li      r3,64
  38:	4d 82 00 20 	beqlr
  3c:	7c 60 00 d0 	neg     r3,r0
  40:	7c 63 00 38 	and     r3,r3,r0
  44:	7c 63 00 74 	cntlzd  r3,r3
  48:	20 63 00 3f 	subfic  r3,r3,63
  4c:	7c 63 07 b4 	extsw   r3,r3
  50:	4e 80 00 20 	blr

On PPC64, after the patch:
0000000000000030 <.testffz>:
  30:	38 03 00 01 	addi    r0,r3,1
  34:	7c 03 18 78 	andc    r3,r0,r3
  38:	7c 63 00 74 	cntlzd  r3,r3
  3c:	20 63 00 3f 	subfic  r3,r3,63
  40:	4e 80 00 20 	blr
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      22ef33b3
    • C
      powerpc: Use builtin functions for fls()/__fls()/fls64() · 2fcff790
      由 Christophe Leroy 提交于 
      With the fls() functions as defined in arch/powerpc/include/asm/bitops.h
GCC will not optimise the code in case of constant parameter.

This patch replaces __fls() by the builtin function, and modifies
fls() and fls64() to use builtins instead of inline assembly

For non constant calls, the generated code is doing the same:

int testfls(unsigned int x)
{
	return fls(x);
}

unsigned long test__fls(unsigned long x)
{
	return __fls(x);
}

int testfls64(__u64 x)
{
	return fls64(x);
}

On PPC32, before the patch:
00000064 <testfls>:
  64:	7c 63 00 34 	cntlzw  r3,r3
  68:	20 63 00 20 	subfic  r3,r3,32
  6c:	4e 80 00 20 	blr

00000070 <test__fls>:
  70:	7c 63 00 34 	cntlzw  r3,r3
  74:	20 63 00 1f 	subfic  r3,r3,31
  78:	4e 80 00 20 	blr

0000007c <testfls64>:
  7c:	2c 03 00 00 	cmpwi   r3,0
  80:	40 82 00 10 	bne     90 <testfls64+0x14>
  84:	7c 83 00 34 	cntlzw  r3,r4
  88:	20 63 00 20 	subfic  r3,r3,32
  8c:	4e 80 00 20 	blr
  90:	7c 63 00 34 	cntlzw  r3,r3
  94:	20 63 00 40 	subfic  r3,r3,64
  98:	4e 80 00 20 	blr

On PPC32, after the patch:
00000054 <testfls>:
  54:	7c 63 00 34 	cntlzw  r3,r3
  58:	20 63 00 20 	subfic  r3,r3,32
  5c:	4e 80 00 20 	blr

00000060 <test__fls>:
  60:	7c 63 00 34 	cntlzw  r3,r3
  64:	20 63 00 1f 	subfic  r3,r3,31
  68:	4e 80 00 20 	blr

0000006c <testfls64>:
  6c:	2c 03 00 00 	cmpwi   r3,0
  70:	41 82 00 10 	beq     80 <testfls64+0x14>
  74:	7c 63 00 34 	cntlzw  r3,r3
  78:	20 63 00 40 	subfic  r3,r3,64
  7c:	4e 80 00 20 	blr
  80:	7c 83 00 34 	cntlzw  r3,r4
  84:	20 63 00 40 	subfic  r3,r3,32
  88:	4e 80 00 20 	blr

On PPC64, before the patch:
00000000000000a0 <.testfls>:
  a0:	7c 63 00 34 	cntlzw  r3,r3
  a4:	20 63 00 20 	subfic  r3,r3,32
  a8:	7c 63 07 b4 	extsw   r3,r3
  ac:	4e 80 00 20 	blr

00000000000000b0 <.test__fls>:
  b0:	7c 63 00 74 	cntlzd  r3,r3
  b4:	20 63 00 3f 	subfic  r3,r3,63
  b8:	7c 63 07 b4 	extsw   r3,r3
  bc:	4e 80 00 20 	blr

00000000000000c0 <.testfls64>:
  c0:	7c 63 00 74 	cntlzd  r3,r3
  c4:	20 63 00 40 	subfic  r3,r3,64
  c8:	7c 63 07 b4 	extsw   r3,r3
  cc:	4e 80 00 20 	blr

On PPC64, after the patch:
0000000000000090 <.testfls>:
  90:	7c 63 00 34 	cntlzw  r3,r3
  94:	20 63 00 20 	subfic  r3,r3,32
  98:	7c 63 07 b4 	extsw   r3,r3
  9c:	4e 80 00 20 	blr

00000000000000a0 <.test__fls>:
  a0:	7c 63 00 74 	cntlzd  r3,r3
  a4:	20 63 00 3f 	subfic  r3,r3,63
  a8:	4e 80 00 20 	blr
  ac:	60 00 00 00 	nop

00000000000000b0 <.testfls64>:
  b0:	7c 63 00 74 	cntlzd  r3,r3
  b4:	20 63 00 40 	subfic  r3,r3,64
  b8:	7c 63 07 b4 	extsw   r3,r3
  bc:	4e 80 00 20 	blr

Those builtins have been in GCC since at least 3.4.6 (see
https://gcc.gnu.org/onlinedocs/gcc-3.4.6/gcc/Other-Builtins.html )
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      2fcff790
    • C
      powerpc: Discard ffs()/__ffs() function and use builtin functions instead · f83647d6
      由 Christophe Leroy 提交于 
      With the ffs() function as defined in arch/powerpc/include/asm/bitops.h
GCC will not optimise the code in case of constant parameter, as shown
by the small exemple below.

int ffs_test(void)
{
	return 4 << ffs(31);
}

c0012334 <ffs_test>:
c0012334:       39 20 00 01     li      r9,1
c0012338:       38 60 00 04     li      r3,4
c001233c:       7d 29 00 34     cntlzw  r9,r9
c0012340:       21 29 00 20     subfic  r9,r9,32
c0012344:       7c 63 48 30     slw     r3,r3,r9
c0012348:       4e 80 00 20     blr

With this patch, the same function will compile as follows:

c0012334 <ffs_test>:
c0012334:       38 60 00 08     li      r3,8
c0012338:       4e 80 00 20     blr

The same happens with __ffs()

For non constant calls, the generated code is doing the same,
allthought it is slightly different on 64 bits for ffs():

unsigned long test__ffs(unsigned long x)
{
	return __ffs(x);
}

int testffs(int x)
{
	return ffs(x);
}

On PPC32, before the patch:
0000003c <test__ffs>:
  3c:	7d 23 00 d0 	neg     r9,r3
  40:	7d 23 18 38 	and     r3,r9,r3
  44:	7c 63 00 34 	cntlzw  r3,r3
  48:	20 63 00 1f 	subfic  r3,r3,31
  4c:	4e 80 00 20 	blr

00000050 <testffs>:
  50:	7d 23 00 d0 	neg     r9,r3
  54:	7d 23 18 38 	and     r3,r9,r3
  58:	7c 63 00 34 	cntlzw  r3,r3
  5c:	20 63 00 20 	subfic  r3,r3,32
  60:	4e 80 00 20 	blr

On PPC32, after the patch:
0000002c <test__ffs>:
  2c:	7d 23 00 d0 	neg     r9,r3
  30:	7d 23 18 38 	and     r3,r9,r3
  34:	7c 63 00 34 	cntlzw  r3,r3
  38:	20 63 00 1f 	subfic  r3,r3,31
  3c:	4e 80 00 20 	blr

00000040 <testffs>:
  40:	7d 23 00 d0 	neg     r9,r3
  44:	7d 23 18 38 	and     r3,r9,r3
  48:	7c 63 00 34 	cntlzw  r3,r3
  4c:	20 63 00 20 	subfic  r3,r3,32
  50:	4e 80 00 20 	blr

On PPC64, before the patch:
0000000000000060 <.test__ffs>:
  60:	7c 03 00 d0 	neg     r0,r3
  64:	7c 03 18 38 	and     r3,r0,r3
  68:	7c 63 00 74 	cntlzd  r3,r3
  6c:	20 63 00 3f 	subfic  r3,r3,63
  70:	7c 63 07 b4 	extsw   r3,r3
  74:	4e 80 00 20 	blr

0000000000000080 <.testffs>:
  80:	7c 03 00 d0 	neg     r0,r3
  84:	7c 03 18 38 	and     r3,r0,r3
  88:	7c 63 00 74 	cntlzd  r3,r3
  8c:	20 63 00 40 	subfic  r3,r3,64
  90:	7c 63 07 b4 	extsw   r3,r3
  94:	4e 80 00 20 	blr

On PPC64, after the patch:
0000000000000050 <.test__ffs>:
  50:	7c 03 00 d0 	neg     r0,r3
  54:	7c 03 18 38 	and     r3,r0,r3
  58:	7c 63 00 74 	cntlzd  r3,r3
  5c:	20 63 00 3f 	subfic  r3,r3,63
  60:	4e 80 00 20 	blr

0000000000000070 <.testffs>:
  70:	7c 03 00 d0 	neg     r0,r3
  74:	7c 03 18 38 	and     r3,r0,r3
  78:	7c 63 00 34 	cntlzw  r3,r3
  7c:	20 63 00 20 	subfic  r3,r3,32
  80:	7c 63 07 b4 	extsw   r3,r3
  84:	4e 80 00 20 	blr
(ffs() operates on an int so cntlzw is equivalent to cntlzd)

In addition, when reading the generated vmlinux, we can observe
that with the builtin functions, GCC sometimes efficiently spreads
the instructions within the generated functions while the inline
assembly force them to remain grouped together.

__builtin_ffs() is already used in arch/powerpc/include/asm/page_32.h

Those builtins have been in GCC since at least 3.4.6 (see
https://gcc.gnu.org/onlinedocs/gcc-3.4.6/gcc/Other-Builtins.html )
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      f83647d6
    • C
      powerpc: Handle simultaneous interrupts at once · 45cb08f4
      由 Christophe Leroy 提交于 
      It often happens to have simultaneous interrupts, for instance
when having double Ethernet attachment. With the current
implementation, we suffer the cost of kernel entry/exit for each
interrupt.

This patch introduces a loop in __do_irq() to handle all interrupts
at once before returning.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      45cb08f4
    • C
      powerpc/8xx: fix mpc8xx_get_irq() return on no irq · 3c29b603
      由 Christophe Leroy 提交于 
      IRQ 0 is a valid HW interrupt. So get_irq() shall return 0 when
there is no irq, instead of returning irq_linear_revmap(... ,0)

Fixes: f2a0bd37 ("[POWERPC] 8xx: powerpc port of core CPM PIC")
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      3c29b603
    • C
      powerpc/40x: Clear MSR_DR in one insn instead of two · 362957c2
      由 Christophe Leroy 提交于 
      Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      362957c2
    • C
      powerpc/mm: The 8xx doesn't call do_page_fault() for breakpoints · 92aa2fe0
      由 Christophe Leroy 提交于 
      The 8xx has a dedicated exception for breakpoints, that directly
calls do_break()
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      92aa2fe0
    • C
      powerpc/mm: Evaluate user_mode(regs) only once in do_page_fault() · da929f6a
      由 Christophe Leroy 提交于 
      Analysis of the assembly code shows that when using user_mode(regs),
at least the 'andi.' is redone all the time, and also
the 'lwz ,132(r31)' most of the time. With the new form, the 'is_user'
is mapped to cr4, then all further use of is_user results in just
things like 'beq cr4,218 <do_page_fault+0x218>'

Without the patch:

  50:	81 1e 00 84 	lwz     r8,132(r30)
  54:	71 09 40 00 	andi.   r9,r8,16384
  58:	40 82 00 0c 	bne     64 <do_page_fault+0x64>

  84:	81 3e 00 84 	lwz     r9,132(r30)
  8c:	71 2a 40 00 	andi.   r10,r9,16384
  90:	41 a2 01 64 	beq     1f4 <do_page_fault+0x1f4>

  d4:	81 3e 00 84 	lwz     r9,132(r30)
  dc:	71 28 40 00 	andi.   r8,r9,16384
  e0:	41 82 02 08 	beq     2e8 <do_page_fault+0x2e8>

 108:	81 3e 00 84 	lwz     r9,132(r30)
 110:	71 28 40 00 	andi.   r8,r9,16384
 118:	41 82 02 28 	beq     340 <do_page_fault+0x340>

 1e4:	81 3e 00 84 	lwz     r9,132(r30)
 1e8:	71 2a 40 00 	andi.   r10,r9,16384
 1ec:	40 82 01 68 	bne     354 <do_page_fault+0x354>

 228:	81 3e 00 84 	lwz     r9,132(r30)
 22c:	71 28 40 00 	andi.   r8,r9,16384
 230:	41 82 ff c4 	beq     1f4 <do_page_fault+0x1f4>

 288:	71 2a 40 00 	andi.   r10,r9,16384
 294:	41 a2 fe 60 	beq     f4 <do_page_fault+0xf4>

 50c:	81 3e 00 84 	lwz     r9,132(r30)
 514:	71 2a 40 00 	andi.   r10,r9,16384
 518:	40 a2 fc e0 	bne     1f8 <do_page_fault+0x1f8>

 534:	81 3e 00 84 	lwz     r9,132(r30)
 53c:	71 2a 40 00 	andi.   r10,r9,16384
 540:	41 82 fc b8 	beq     1f8 <do_page_fault+0x1f8>

This patch creates a local var called 'is_user' which contains the
result of user_mode(regs)

With the patch:

  20:	81 03 00 84 	lwz     r8,132(r3)
  48:	55 09 97 fe 	rlwinm  r9,r8,18,31,31
  58:	2e 09 00 00 	cmpwi   cr4,r9,0
  5c:	40 92 00 0c 	bne     cr4,68 <do_page_fault+0x68>

  88:	41 b2 01 90 	beq     cr4,218 <do_page_fault+0x218>

  d4:	40 92 01 d0 	bne     cr4,2a4 <do_page_fault+0x2a4>

 120:	41 b2 00 f8 	beq     cr4,218 <do_page_fault+0x218>

 138:	41 b2 ff a0 	beq     cr4,d8 <do_page_fault+0xd8>

 1d4:	40 92 00 e0 	bne     cr4,2b4 <do_page_fault+0x2b4>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      da929f6a
    • C
      powerpc/mm: Remove a redundant test in do_page_fault() · 97a011e6
      由 Christophe Leroy 提交于 
      The result of (trap == 0x400) is already in is_exec.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      97a011e6
    • C
      powerpc/mm: Only call store_updates_sp() on stores in do_page_fault() · e8de85ca
      由 Christophe Leroy 提交于 
      Function store_updates_sp() checks whether the faulting
instruction is a store updating r1. Therefore we can limit its calls
to store exceptions.

This patch is an improvement of commit a7a9dcd8 ("powerpc: Avoid
taking a data miss on every userspace instruction miss")

With the same microbenchmark app, run with 500 as argument, on an
MPC885 we get:

Before this patch: 152000 DTLB misses
After this patch:  147000 DTLB misses
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      e8de85ca
    • C
      powerpc/mm: Remove __this_fixmap_does_not_exist() · 9affa9e2
      由 Christophe Leroy 提交于 
      This function has not been used since commit 9494a1e8
("powerpc: use generic fixmap.h)
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      9affa9e2
    • B
      powerpc/mm/ptdump: Dump the first entry of the linear mapping as well · e63739b1
      由 Balbir Singh 提交于 
      The check in hpte_find() should be < and not <= for PAGE_OFFSET
Signed-off-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      e63739b1
  3. 30 5月, 2017 22 次提交