e7734ef14e
NCR5380_poll_politely2() uses in_interrupt() and irqs_disabled() to check
if it is safe to sleep.
Such usage in drivers is phased out and Linus clearly requested that code
which changes behaviour depending on context should either be separated, or
the context be explicitly conveyed in an argument passed by the caller.
Below is a context analysis of NCR5380_poll_politely2() uppermost callers:
- NCR5380_maybe_reset_bus(), task, invoked during device probe.
-> NCR5380_poll_politely()
-> do_abort()
- NCR5380_select(), task, but can only sleep in the "release, then
re-acquire" regions of the spinlock held by its caller.
Sleeping invocations (lock released):
-> NCR5380_poll_politely2()
Atomic invocations (lock acquired):
-> NCR5380_reselect()
-> NCR5380_poll_politely()
-> do_abort()
-> NCR5380_transfer_pio()
- NCR5380_intr(), interrupt handler
-> NCR5380_dma_complete()
-> NCR5380_transfer_pio()
-> NCR5380_poll_politely()
-> NCR5380_reselect() (see above)
- NCR5380_information_transfer(), task, but can only sleep in the
"release, then re-acquire" regions of the caller-held spinlock.
Sleeping invocations (lock released):
- NCR5380_transfer_pio() -> NCR5380_poll_politely()
- NCR5380_poll_politely()
Atomic invocations (lock acquired):
- NCR5380_transfer_dma()
-> NCR5380_dma_recv_setup()
=> generic_NCR5380_precv() -> NCR5380_poll_politely()
=> macscsi_pread() -> NCR5380_poll_politely()
-> NCR5380_dma_send_setup()
=> generic_NCR5380_psend -> NCR5380_poll_politely2()
=> macscsi_pwrite() -> NCR5380_poll_politely()
-> NCR5380_poll_politely2()
-> NCR5380_dma_complete()
-> NCR5380_transfer_pio()
-> NCR5380_poll_politely()
- NCR5380_transfer_pio() -> NCR5380_poll_politely
- NCR5380_reselect(), atomic, always called with hostdata spinlock
held.
Since NCR5380_poll_politely2() already takes a "wait" argument in jiffies,
use it to determine if the function can sleep. Modify atomic callers, which
passed an unused wait value in terms of HZ, to pass zero.
Link: https://lore.kernel.org/r/20201206075157.19067-1-a.darwish@linutronix.de
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: <linux-m68k@lists.linux-m68k.org>
Suggested-by: Finn Thain <fthain@telegraphics.com.au>
Co-developed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.