-
Javier González authored
In order to respect mw_cuinits, pblk's write buffer maintains a backpointer to protect data not yet persisted; when writing to the write buffer, this backpointer defines a threshold that pblk's rate-limiter enforces. On small PU configurations, the following scenarios might take place: (i) the threshold is larger than the write buffer and (ii) the threshold is smaller than the write buffer, but larger than the maximun allowed split bio - 256KB at this moment (Note that writes are not always split - we only do this when we the size of the buffer is smaller than the buffer). In both cases, pblk's rate-limiter prevents the I/O to be written to the buffer, thus stalling. This patch fixes the original backpointer implementation by considering the threshold both on buffer creation and on the rate-limiters path, when bio_split is triggered (case (ii) above). Fixes: 766c8ceb ("lightnvm: pblk: guarantee that backpointer is respected on writer stall") Signed-off-by:
Javier González <javier@javigon.com> Reviewed-by:
Hans Holmberg <hans.holmberg@cnexlabs.com> Signed-off-by:
Matias Bjørling <mb@lightnvm.io> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
b4cdc426