2015-11-16 16:58:45

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH] pNFS/flexfiles: Support server-supplied layoutstats sampling period

Some servers want to be able to control the frequency with which clients
report layoutstats, for instance, in order to monitor QoS for a particular
file or set of file. In order to support this, the flexfiles layout allows
the server to pass this info as a hint in the layout payload.

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/flexfilelayout/flexfilelayout.c | 16 +++++++++++++---
fs/nfs/flexfilelayout/flexfilelayout.h | 1 +
2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 03516c80855a..616817a46410 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -505,9 +505,17 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
}

p = xdr_inline_decode(&stream, 4);
- if (p)
- fls->flags = be32_to_cpup(p);
+ if (!p)
+ goto out_sort_mirrors;
+ fls->flags = be32_to_cpup(p);
+
+ p = xdr_inline_decode(&stream, 4);
+ if (!p)
+ goto out_sort_mirrors;
+ for (i=0; i < fls->mirror_array_cnt; i++)
+ fls->mirror_array[i]->report_interval = be32_to_cpup(p);

+out_sort_mirrors:
ff_layout_sort_mirrors(fls);
rc = ff_layout_check_layout(lgr);
if (rc)
@@ -603,7 +611,9 @@ nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
mirror->start_time = now;
if (ktime_equal(mirror->last_report_time, notime))
mirror->last_report_time = now;
- if (layoutstats_timer != 0)
+ if (mirror->report_interval != 0)
+ report_interval = (s64)mirror->report_interval * 1000LL;
+ else if (layoutstats_timer != 0)
report_interval = (s64)layoutstats_timer * 1000LL;
if (ktime_to_ms(ktime_sub(now, mirror->last_report_time)) >=
report_interval) {
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h
index 2bb08bc6aaf0..dd353bb7dc0a 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.h
+++ b/fs/nfs/flexfilelayout/flexfilelayout.h
@@ -85,6 +85,7 @@ struct nfs4_ff_layout_mirror {
struct nfs4_ff_layoutstat write_stat;
ktime_t start_time;
ktime_t last_report_time;
+ u32 report_interval;
};

struct nfs4_ff_layout_segment {
--
2.5.0