This series implements the very slow but correct handling for blkdev_issue_flush() with DAX mappings, as discussed here:
https://lkml.org/lkml/2015/10/26/116 I don't think that we can actually do the on_each_cpu(sync_cache, ...); ...where sync_cache is something like: cache_disable(); wbinvd(); pcommit(); cache_enable(); solution as proposed by Dan because WBINVD + PCOMMIT doesn't guarantee that your writes actually make it durably onto the DIMMs. I believe you really do need to loop through the cache lines, flush them with CLWB, then fence and PCOMMIT. I do worry that the cost of blindly flushing the entire PMEM namespace on each fsync or msync will be prohibitively expensive, and that we'll by very incentivized to move to the radix tree based dirty page tracking as soon as possible. :) Ross Zwisler (2): pmem: add wb_cache_pmem() to the PMEM API pmem: Add simple and slow fsync/msync support arch/x86/include/asm/pmem.h | 11 ++++++----- drivers/nvdimm/pmem.c | 10 +++++++++- include/linux/pmem.h | 22 +++++++++++++++++++++- 3 files changed, 36 insertions(+), 7 deletions(-) -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
