sevki
c9e1dba412
setup CI/CD for kernel development - added CodeQL for code scanning - every pr is built as an image and is available for 30days on https://oklinux.dev - tagged and released on github for now Signed-off-by: sevki <s@sevki.io>
41 lines
640 B
Text
41 lines
640 B
Text
C RM-fixed
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(*
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* Result: Never
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*
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* This litmus test demonstrates that the old "roach motel" approach
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* to locking, where code can be freely moved into critical sections,
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* cannot be used in the Linux kernel.
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*)
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{
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int x;
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atomic_t y;
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}
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P0(int *x, atomic_t *y, spinlock_t *lck)
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{
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int r2;
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spin_lock(lck);
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r2 = atomic_inc_return(y);
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WRITE_ONCE(*x, 1);
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spin_unlock(lck);
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}
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P1(int *x, atomic_t *y, spinlock_t *lck)
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{
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int r0;
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int r1;
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int r2;
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r0 = READ_ONCE(*x);
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r1 = READ_ONCE(*x);
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spin_lock(lck);
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r2 = atomic_inc_return(y);
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spin_unlock(lck);
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}
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locations [x;0:r2;1:r0;1:r1;1:r2]
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filter (1:r0=0 /\ 1:r1=1)
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exists (1:r2=1)
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