ARM: smp: Store current pointer in TPIDRURO register if available
Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.
Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.
<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
2021-09-18 10:44:37 +02:00
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/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (c) 2021 Keith Packard <keithp@keithp.com>
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* Copyright (c) 2021 Google, LLC <ardb@kernel.org>
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*/
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#ifndef _ASM_ARM_CURRENT_H
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#define _ASM_ARM_CURRENT_H
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#ifndef __ASSEMBLY__
|
ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems
On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.
To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-11-24 14:08:11 +01:00
|
|
|
#include <asm/insn.h>
|
ARM: smp: Store current pointer in TPIDRURO register if available
Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.
Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.
<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
2021-09-18 10:44:37 +02:00
|
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struct task_struct;
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|
|
|
ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems
On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.
To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-11-24 14:08:11 +01:00
|
|
|
extern struct task_struct *__current;
|
ARM: smp: Store current pointer in TPIDRURO register if available
Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.
Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.
<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
2021-09-18 10:44:37 +02:00
|
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|
2022-01-24 23:32:51 +01:00
|
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|
static __always_inline __attribute_const__ struct task_struct *get_current(void)
|
ARM: smp: Store current pointer in TPIDRURO register if available
Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.
Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.
<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
2021-09-18 10:44:37 +02:00
|
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|
{
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struct task_struct *cur;
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2024-01-25 15:55:10 -07:00
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#if __has_builtin(__builtin_thread_pointer) && defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO)
|
ARM: smp: Store current pointer in TPIDRURO register if available
Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.
Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.
<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
2021-09-18 10:44:37 +02:00
|
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/*
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* Use the __builtin helper when available - this results in better
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* code, especially when using GCC in combination with the per-task
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* stack protector, as the compiler will recognize that it needs to
|
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* load the TLS register only once in every function.
|
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*/
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cur = __builtin_thread_pointer();
|
ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems
On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.
To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-11-24 14:08:11 +01:00
|
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#elif defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
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asm("0: mrc p15, 0, %0, c13, c0, 3 \n\t"
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#ifdef CONFIG_CPU_V6
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"1: \n\t"
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" .subsection 1 \n\t"
|
2022-01-24 19:16:58 +01:00
|
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#if defined(CONFIG_ARM_HAS_GROUP_RELOCS) && \
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!(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
|
ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems
On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.
To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-11-24 14:08:11 +01:00
|
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"2: " LOAD_SYM_ARMV6(%0, __current) " \n\t"
|
|
|
|
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" b 1b \n\t"
|
ARM: 9176/1: avoid literal references in inline assembly
Nathan reports that the new get_current() and per-CPU offset accessors
may cause problems at build time due to the use of a literal to hold the
address of the respective variables. This is due to the fact that LLD
before v14 does not support the PC-relative group relocations that are
normally used for this, and the fallback relies on literals but does not
emit the literal pools explictly using the .ltorg directive.
./arch/arm/include/asm/current.h:53:6: error: out of range pc-relative fixup value
asm(LOAD_SYM_ARMV6(%0, __current) : "=r"(cur));
^
./arch/arm/include/asm/insn.h:25:2: note: expanded from macro 'LOAD_SYM_ARMV6'
" ldr " #reg ", =" #sym " nt"
^
<inline asm>:1:3: note: instantiated into assembly here
ldr r0, =__current
^
Since emitting a literal pool in this particular case is not possible,
let's avoid the LOAD_SYM_ARMV6() entirely, and use the ordinary C
assigment instead.
As it turns out, there are other such cases, and here, using .ltorg to
emit the literal pool within range of the LDR instruction would be
possible due to the presence of an unconditional branch right after it.
Unfortunately, putting .ltorg directives in subsections appears to
confuse the Clang inline assembler, resulting in similar errors even
though the .ltorg is most definitely within range.
So let's fix this by emitting the literal explicitly, and not rely on
the assembler to figure this out. This means we have move the fallback
out of the LOAD_SYM_ARMV6() macro and into the callers.
Link: https://github.com/ClangBuiltLinux/linux/issues/1551
Fixes: 9c46929e7989 ("ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-12-24 10:31:00 +01:00
|
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#else
|
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|
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"2: ldr %0, 3f \n\t"
|
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" ldr %0, [%0] \n\t"
|
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|
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" b 1b \n\t"
|
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|
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|
"3: .long __current \n\t"
|
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|
#endif
|
ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems
On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.
To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-11-24 14:08:11 +01:00
|
|
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" .previous \n\t"
|
|
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" .pushsection \".alt.smp.init\", \"a\" \n\t"
|
|
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|
|
" .long 0b - . \n\t"
|
|
|
|
|
" b . + (2b - 0b) \n\t"
|
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|
" .popsection \n\t"
|
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|
#endif
|
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|
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: "=r"(cur));
|
ARM: 9176/1: avoid literal references in inline assembly
Nathan reports that the new get_current() and per-CPU offset accessors
may cause problems at build time due to the use of a literal to hold the
address of the respective variables. This is due to the fact that LLD
before v14 does not support the PC-relative group relocations that are
normally used for this, and the fallback relies on literals but does not
emit the literal pools explictly using the .ltorg directive.
./arch/arm/include/asm/current.h:53:6: error: out of range pc-relative fixup value
asm(LOAD_SYM_ARMV6(%0, __current) : "=r"(cur));
^
./arch/arm/include/asm/insn.h:25:2: note: expanded from macro 'LOAD_SYM_ARMV6'
" ldr " #reg ", =" #sym " nt"
^
<inline asm>:1:3: note: instantiated into assembly here
ldr r0, =__current
^
Since emitting a literal pool in this particular case is not possible,
let's avoid the LOAD_SYM_ARMV6() entirely, and use the ordinary C
assigment instead.
As it turns out, there are other such cases, and here, using .ltorg to
emit the literal pool within range of the LDR instruction would be
possible due to the presence of an unconditional branch right after it.
Unfortunately, putting .ltorg directives in subsections appears to
confuse the Clang inline assembler, resulting in similar errors even
though the .ltorg is most definitely within range.
So let's fix this by emitting the literal explicitly, and not rely on
the assembler to figure this out. This means we have move the fallback
out of the LOAD_SYM_ARMV6() macro and into the callers.
Link: https://github.com/ClangBuiltLinux/linux/issues/1551
Fixes: 9c46929e7989 ("ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-12-24 10:31:00 +01:00
|
|
|
#elif __LINUX_ARM_ARCH__>= 7 || \
|
2022-01-24 19:16:58 +01:00
|
|
|
!defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \
|
|
|
|
|
(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
|
ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems
On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.
To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-11-24 14:08:11 +01:00
|
|
|
cur = __current;
|
ARM: smp: Store current pointer in TPIDRURO register if available
Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.
Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.
<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
2021-09-18 10:44:37 +02:00
|
|
|
#else
|
ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems
On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.
To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-11-24 14:08:11 +01:00
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asm(LOAD_SYM_ARMV6(%0, __current) : "=r"(cur));
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ARM: smp: Store current pointer in TPIDRURO register if available
Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.
Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.
<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
2021-09-18 10:44:37 +02:00
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#endif
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return cur;
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}
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#define current get_current()
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#endif /* __ASSEMBLY__ */
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#endif /* _ASM_ARM_CURRENT_H */
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