pstore: Adjust buffer size for compression for smaller registered buffers
authorAruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Wed, 11 Sep 2013 17:57:41 +0000 (10:57 -0700)
committerTony Luck <tony.luck@intel.com>
Mon, 16 Sep 2013 16:28:28 +0000 (09:28 -0700)
commit7de8fe2fa8f94985a83120f04d41a93425ea66ba
tree30fb66a6e04b3dcba8fe6d21be01b3cf5e9e203f
parente831cbfc1ad843b5542cc45f777e1a00b73c0685
pstore: Adjust buffer size for compression for smaller registered buffers

When backends (ex: efivars) have smaller registered buffers, the
big_oops_buf is too big for them as number of repeated occurences
in the text captured will be less. What happens is that pstore takes
too big a bite from the dmesg log and then finds it cannot compress it
enough to meet the backend block size. Patch takes care of adjusting
the buffer size based on the registered buffer size. cmpr values have
been arrived after doing experiments with plain text for buffers of
size 1k - 4k (Smaller the buffer size repeated occurence will be less)
and with sample crash log for buffers ranging from 4k - 10k.

Reported-by: Seiji Aguchi <seiji.aguchi@hds.com>
Tested-by: Seiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
fs/pstore/platform.c