forked from Minki/linux
ef4b4b274c
`comedi_event()` is called from low-level drivers to handle comedi asynchronous command event flags. As a safety check, it checks the subdevice's "run" flags to make sure an asynchronous command is running. It can also change the run flags to mark the command as no longer running (possibly also marking it as terminated with an error). Checking the runflags and modifying them involves two uses of the subdevice's spin-lock. It seems better to do it with a single use of the spin-lock. This also avoids possible interactions with `do_become_nonbusy()`. Acquire the subdevice's spin-lock at the start of `comedi_event()` and release it near the end, before a possible call to `kill_fasync()` (but after it's parameter values have been determined). Add and make use of few new inline helper functions: * `__comedi_clear_subdevice_runflags()` -- clears some run flags without using the spin-lock * `__comedi_set_subdevice_runflags()` -- sets some run flags without using the spin-lock * `__comedi_get_subdevice_runflags()` -- a spin-lockless version of `comedi_get_subdevice_runflags() * `__comedi_is_subdevice_running()` -- a spin-lockless version of * `comedi_is_subdevice_running()` Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| .. | ||
| drivers | ||
| kcomedilib | ||
| comedi_buf.c | ||
| comedi_compat32.c | ||
| comedi_compat32.h | ||
| comedi_fops.c | ||
| comedi_internal.h | ||
| comedi_pci.c | ||
| comedi_pci.h | ||
| comedi_pcmcia.c | ||
| comedi_pcmcia.h | ||
| comedi_usb.c | ||
| comedi_usb.h | ||
| comedi.h | ||
| comedidev.h | ||
| comedilib.h | ||
| drivers.c | ||
| Kconfig | ||
| Makefile | ||
| proc.c | ||
| range.c | ||
| TODO | ||