@@ -540,7 +540,7 @@ static void ssd_commit_superblock(struct dm_writecache *wc)
static void writecache_commit_flushed(struct dm_writecache *wc, bool wait_for_ios)
{
if (WC_MODE_PMEM(wc))
- wmb();
+ arch_pmem_flush_barrier();
else
ssd_commit_flushed(wc, wait_for_ios);
}
@@ -1216,13 +1216,13 @@ int generic_nvdimm_flush(struct nd_region *nd_region)
idx = this_cpu_add_return(flush_idx, hash_32(current->pid + idx, 8));
/*
- * The first wmb() is needed to 'sfence' all previous writes
- * such that they are architecturally visible for the platform
- * buffer flush. Note that we've already arranged for pmem
+ * The first arch_pmem_flush_barrier() is needed to 'sfence' all
+ * previous writes such that they are architecturally visible for
+ * the platform buffer flush. Note that we've already arranged for pmem
* writes to avoid the cache via memcpy_flushcache(). The final
* wmb() ensures ordering for the NVDIMM flush write.
*/
- wmb();
+ arch_pmem_flush_barrier();
for (i = 0; i < nd_region->ndr_mappings; i++)
if (ndrd_get_flush_wpq(ndrd, i, 0))
writeq(1, ndrd_get_flush_wpq(ndrd, i, idx));
@@ -286,4 +286,8 @@ static inline void arch_invalidate_pmem(void *addr, size_t size)
}
#endif
+#ifndef arch_pmem_flush_barrier
+#define arch_pmem_flush_barrier() wmb()
+#endif
+
#endif /* __LIBNVDIMM_H__ */
Architectures like ppc64 provide persistent memory specific barriers that will ensure that all stores for which the modifications are written to persistent storage by preceding dcbfps and dcbstps instructions have updated persistent storage before any data access or data transfer caused by subsequent instructions is initiated. This is in addition to the ordering done by wmb() Update nvdimm core such that architecture can use barriers other than wmb to ensure all previous writes are architecturally visible for the platform buffer flush. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> --- drivers/md/dm-writecache.c | 2 +- drivers/nvdimm/region_devs.c | 8 ++++---- include/linux/libnvdimm.h | 4 ++++ 3 files changed, 9 insertions(+), 5 deletions(-)