Messages in this thread |  | | | Date | Sun, 03 Feb 2002 23:27:49 +0100 | | From | Steffen Persvold <> | | Subject | Re: Short question regarding generic_make_request() |
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Jens Axboe wrote: > > On Sun, Feb 03 2002, Ingo Molnar wrote: > > > > On Sun, 3 Feb 2002, Steffen Persvold wrote: > > > > > Can generic_make_request() be called from interrupt level (or tasklet) > > > ? > > > > no. > > In theory, READA from interrupt context would be ok, though. That > doesn't work in real-life due to the non flag saving spin locking in > __make_request. >
Ok, the reason I'm asking is that I receive a request from a remote machine on interrupt level (tasklet) and want to submit this to the local device. The reason I'm using a tasklet instead of a kernel thread is that somewhere between RedHat's 2.4.3-12 and 2.4.9-12 kernels the latency of waking up a kernel thread increased (using a semaphore method similar to the one used in loop.c). I don't know why this happened, but I guess that if I still could use a kernel thread there wouldn't be any problems using generic_make_request().
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