pNFS/filelayout: Fix coalescing test for single DS

When there is a single DS no striping constraints need to be placed on
the IO. When such constraint is applied then buffered reads don't
coalesce to the DS's rsize.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Olga Kornievskaia 2022-12-20 12:31:29 -05:00 committed by Trond Myklebust
parent b18cba09e3
commit a6b9d2fa00

View File

@ -783,6 +783,12 @@ filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
return &fl->generic_hdr;
}
static bool
filelayout_lseg_is_striped(const struct nfs4_filelayout_segment *flseg)
{
return flseg->num_fh > 1;
}
/*
* filelayout_pg_test(). Called by nfs_can_coalesce_requests()
*
@ -803,6 +809,8 @@ filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
size = pnfs_generic_pg_test(pgio, prev, req);
if (!size)
return 0;
else if (!filelayout_lseg_is_striped(FILELAYOUT_LSEG(pgio->pg_lseg)))
return size;
/* see if req and prev are in the same stripe */
if (prev) {