2014-10-06 05:44:43 +08:00
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#
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# For a description of the syntax of this configuration file,
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2015-06-28 22:08:57 +08:00
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# see the file kconfig-language.txt in the NuttX tools repository.
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2014-10-06 05:44:43 +08:00
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#
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config FS_AIO
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bool "Asynchronous I/O support"
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default n
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depends on SCHED_LPWORK
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---help---
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Enable support for aynchronous I/O. This selection enables the
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interfaces declared in include/aio.h.
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if FS_AIO
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2014-10-06 22:10:02 +08:00
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config FS_NAIOC
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int "Pre-allocated AIO containers"
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default 8
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---help---
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The AIO containers hold an AIO control block and appends information
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needed by the logic running within the RTOS. These structures are
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pre-allocated, the number pre-allocated controlled by this setting.
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This setting controls the number of asynchronous I/O operations that
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can be queued at one time. When this count is exhausted, the caller
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of aio_read(), aio_write(), or aio_fsync() will be forced to wait
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for an available container. That wait is minimized because each
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container is released prior to starting the next I/O.
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The AIO logic includes priority inheritance logic to prevent
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priority inversion problems: The priority of the low-priority work
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queue will be boosted, if necessary, to level of the waiting thread.
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2014-10-06 05:44:43 +08:00
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endif
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