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x86/percpu: Fix x86_this_cpu_variable_test_bit() asm template

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Fix x86_this_cpu_variable_test_bit(), which is implemented with an
incorrect asm template, where argument 2 (count argument) is considered
a percpu variable. However, x86_this_cpu_test_bit() is currently
used exclusively with constant bit number argument, so the called
x86_this_cpu_variable_test_bit() function is never instantiated.

The fix introduces named assembler operands to prevent this kind
of error.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lore.kernel.org/r/20240404094218.448963-1-ubizjak@gmail.com
This commit is contained in:
Uros Bizjak 2024-04-04 11:42:01 +02:00 committed by Ingo Molnar
parent 9ebe5500d4
commit 4c3677c077
1 changed files with 3 additions and 2 deletions
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5
arch/x86/include/asm/percpu.h
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@ -586,10 +586,11 @@ static inline bool x86_this_cpu_variable_test_bit(int nr,
{
bool oldbit;
asm volatile("btl "__percpu_arg(2)",%1"
asm volatile("btl %[nr], " __percpu_arg([var])
CC_SET(c)
: CC_OUT(c) (oldbit)
: "m" (*__my_cpu_ptr((unsigned long __percpu *)(addr))), "Ir" (nr));
: [var] "m" (*__my_cpu_ptr((unsigned long __percpu *)(addr))),
[nr] "Ir" (nr));
return oldbit;
}