1WAIT_ON_BIT(9) Driver Basics WAIT_ON_BIT(9)
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6 wait_on_bit - wait for a bit to be cleared
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9 int wait_on_bit(void * word, int bit, unsigned mode);
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12 word
13 the word being waited on, a kernel virtual address
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15 bit
16 the bit of the word being waited on
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18 mode
19 the task state to sleep in
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22 There is a standard hashed waitqueue table for generic use. This is the
23 part of the hashtable's accessor API that waits on a bit. For instance,
24 if one were to have waiters on a bitflag, one would call wait_on_bit in
25 threads waiting for the bit to clear. One uses wait_on_bit where one is
26 waiting for the bit to clear, but has no intention of setting it.
27 Returned value will be zero if the bit was cleared, or non-zero if the
28 process received a signal and the mode permitted wakeup on that signal.
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31Kernel Hackers Manual 3.10 June 2019 WAIT_ON_BIT(9)