linux-stable.git/arch/powerpc/kernel/interrupt.c, branch v5.12.2

powerpc/traps: unrecoverable_exception() is not an interrupt handler

2021-03-12T00:02:12+00:00

unrecoverable_exception() is called from interrupt handlers or
after an interrupt handler has failed.

Make it a standard function to avoid doubling the actions
performed on interrupt entry (e.g.: user time accounting).

Fixes: 3a96570ffceb ("powerpc: convert interrupt handlers to use wrappers")
Signed-off-by: Christophe Leroy 
Reviewed-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/ae96c59fa2cb7f24a8929c58cfa2c909cb8ff1f1.1615291471.git.christophe.leroy@csgroup.eu

powerpc/syscall: Force inlining of __prep_irq_for_enabled_exit()

2021-03-01T01:33:31+00:00

As reported by kernel test robot, a randconfig with high amount of
debuging options can lead to build failure for undefined reference
to replay_soft_interrupts() on ppc32.

This is due to gcc not seeing that __prep_irq_for_enabled_exit()
always returns true on ppc32 because it doesn't inline it for
some reason.

Force inlining of __prep_irq_for_enabled_exit() to fix the build.

Fixes: 344bb20b159d ("powerpc/syscall: Make interrupt.c buildable on PPC32")
Reported-by: kernel test robot 
Signed-off-by: Christophe Leroy 
Acked-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/53f3a1f719441761000c41154602bf097d4350b5.1614148356.git.christophe.leroy@csgroup.eu

powerpc/syscall: Avoid storing 'current' in another pointer

2021-02-11T12:35:13+00:00

By saving the pointer pointing to thread_info.flags, gcc copies r2
in a non-volatile register.

We know 'current' doesn't change, so avoid that intermediaite pointer.

Reduces null_syscall benchmark by 2 cycles (322 => 320 cycles)

On PPC64, gcc seems to know that 'current' is not changing, and it keeps
it in a non volatile register to avoid multiple read of 'current' in paca.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/ad0363ff0ff8c125f40e1cdc589a85bbd7e31693.1612946484.git.christophe.leroy@csgroup.eu

powerpc/32: Handle bookE debugging in C in syscall entry/exit

2021-02-11T12:35:12+00:00

The handling of SPRN_DBCR0 and other registers can easily
be done in C instead of ASM.

For that, create booke_load_dbcr0() and booke_restore_dbcr0().

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/1a7515f9258b27a9177de88491a8bb79b255ceb7.1612898425.git.christophe.leroy@csgroup.eu

powerpc/syscall: Do not check unsupported scv vector on PPC32

2021-02-11T12:35:12+00:00

Only book3s/64 has scv. No need to check the 0x7ff0 trap on 32 or 64e.
For that, add a helper trap_is_unsupported_scv() similar to
trap_is_scv().

And ignore the scv parameter in syscall_exit_prepare (Save 14 cycles
346 => 332 cycles)

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/fb87b205ae8eb8c623f33bb316801acf95a831e6.1612898425.git.christophe.leroy@csgroup.eu

powerpc/syscall: Change condition to check MSR_RI

2021-02-11T12:35:11+00:00

In system_call_exception(), MSR_RI also needs to be checked on 8xx.
Only booke and 40x doesn't have MSR_RI.

Signed-off-by: Christophe Leroy 
Reviewed-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/67820fada8dd6a8fe9d7b666f175d4cc9d8de87e.1612796617.git.christophe.leroy@csgroup.eu

powerpc/syscall: Save r3 in regs->orig_r3

2021-02-11T12:35:10+00:00

Save r3 in regs->orig_r3 in system_call_exception()

Signed-off-by: Christophe Leroy 
Reviewed-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/9a90805ab6b9101b46daf56470f457a57acd86fc.1612796617.git.christophe.leroy@csgroup.eu

powerpc/syscall: Use is_compat_task()

2021-02-11T12:35:10+00:00

Instead of hard comparing task flags with _TIF_32BIT, use
is_compat_task(). The advantage is that it returns 0 on PPC32
allthough _TIF_32BIT is always set.

Signed-off-by: Christophe Leroy 
Reviewed-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/c8094662199337a7200fea9f6e1d1f8b1b6d5f69.1612796617.git.christophe.leroy@csgroup.eu

powerpc/syscall: Make interrupt.c buildable on PPC32

2021-02-11T12:35:10+00:00

To allow building interrupt.c on PPC32, ifdef out specific PPC64
code or use helpers which are available on both PP32 and PPC64

Modify Makefile to always build interrupt.o

Signed-off-by: Christophe Leroy 
Reviewed-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/ba073ad67bd971a88ce331b65d6655523b54c794.1612796617.git.christophe.leroy@csgroup.eu

powerpc/syscall: Rename syscall_64.c into interrupt.c

2021-02-11T12:35:10+00:00

syscall_64.c will be reused almost as is for PPC32.

As this file also contains functions to handle other types
of interrupts rename it interrupt.c

Signed-off-by: Christophe Leroy 
Reviewed-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/cddc2deaa8f049d3ec419738e69804934919b935.1612796617.git.christophe.leroy@csgroup.eu