pnfs/flexfiles: Add tracepoints for detecting pnfs fallback to MDS

Add tracepoints to allow debugging of the event chain leading to
a pnfs fallback to doing I/O through the MDS.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Trond Myklebust 2019-07-18 09:32:17 -04:00
parent 58bbeab425
commit d5b9216fd5
5 changed files with 112 additions and 1 deletions

View File

@ -934,6 +934,10 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
if (pgio->pg_error < 0)
return;
out_mds:
trace_pnfs_mds_fallback_pg_init_read(pgio->pg_inode,
0, NFS4_MAX_UINT64, IOMODE_READ,
NFS_I(pgio->pg_inode)->layout,
pgio->pg_lseg);
pnfs_put_lseg(pgio->pg_lseg);
pgio->pg_lseg = NULL;
nfs_pageio_reset_read_mds(pgio);
@ -1000,6 +1004,10 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
return;
out_mds:
trace_pnfs_mds_fallback_pg_init_write(pgio->pg_inode,
0, NFS4_MAX_UINT64, IOMODE_RW,
NFS_I(pgio->pg_inode)->layout,
pgio->pg_lseg);
pnfs_put_lseg(pgio->pg_lseg);
pgio->pg_lseg = NULL;
nfs_pageio_reset_write_mds(pgio);
@ -1026,6 +1034,10 @@ ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
if (pgio->pg_lseg)
return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
trace_pnfs_mds_fallback_pg_get_mirror_count(pgio->pg_inode,
0, NFS4_MAX_UINT64, IOMODE_RW,
NFS_I(pgio->pg_inode)->layout,
pgio->pg_lseg);
/* no lseg means that pnfs is not in use, so no mirroring here */
nfs_pageio_reset_write_mds(pgio);
out:
@ -1075,6 +1087,10 @@ static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
hdr->args.count,
(unsigned long long)hdr->args.offset);
trace_pnfs_mds_fallback_write_done(hdr->inode,
hdr->args.offset, hdr->args.count,
IOMODE_RW, NFS_I(hdr->inode)->layout,
hdr->lseg);
task->tk_status = pnfs_write_done_resend_to_mds(hdr);
}
}
@ -1094,6 +1110,10 @@ static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
hdr->args.count,
(unsigned long long)hdr->args.offset);
trace_pnfs_mds_fallback_read_done(hdr->inode,
hdr->args.offset, hdr->args.count,
IOMODE_READ, NFS_I(hdr->inode)->layout,
hdr->lseg);
task->tk_status = pnfs_read_done_resend_to_mds(hdr);
}
}
@ -1827,6 +1847,9 @@ ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
out_failed:
if (ff_layout_avoid_mds_available_ds(lseg))
return PNFS_TRY_AGAIN;
trace_pnfs_mds_fallback_read_pagelist(hdr->inode,
hdr->args.offset, hdr->args.count,
IOMODE_READ, NFS_I(hdr->inode)->layout, lseg);
return PNFS_NOT_ATTEMPTED;
}
@ -1892,6 +1915,9 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
out_failed:
if (ff_layout_avoid_mds_available_ds(lseg))
return PNFS_TRY_AGAIN;
trace_pnfs_mds_fallback_write_pagelist(hdr->inode,
hdr->args.offset, hdr->args.count,
IOMODE_RW, NFS_I(hdr->inode)->layout, lseg);
return PNFS_NOT_ATTEMPTED;
}

View File

@ -16,4 +16,12 @@
EXPORT_TRACEPOINT_SYMBOL_GPL(nfs4_pnfs_read);
EXPORT_TRACEPOINT_SYMBOL_GPL(nfs4_pnfs_write);
EXPORT_TRACEPOINT_SYMBOL_GPL(nfs4_pnfs_commit_ds);
EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_pg_init_read);
EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_pg_init_write);
EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_pg_get_mirror_count);
EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_read_done);
EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_write_done);
EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_read_pagelist);
EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_write_pagelist);
#endif

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@ -1771,6 +1771,7 @@ TRACE_DEFINE_ENUM(PNFS_UPDATE_LAYOUT_BLOCKED);
TRACE_DEFINE_ENUM(PNFS_UPDATE_LAYOUT_INVALID_OPEN);
TRACE_DEFINE_ENUM(PNFS_UPDATE_LAYOUT_RETRY);
TRACE_DEFINE_ENUM(PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
TRACE_DEFINE_ENUM(PNFS_UPDATE_LAYOUT_EXIT);
#define show_pnfs_update_layout_reason(reason) \
__print_symbolic(reason, \
@ -1786,7 +1787,8 @@ TRACE_DEFINE_ENUM(PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
{ PNFS_UPDATE_LAYOUT_BLOCKED, "layouts blocked" }, \
{ PNFS_UPDATE_LAYOUT_INVALID_OPEN, "invalid open" }, \
{ PNFS_UPDATE_LAYOUT_RETRY, "retrying" }, \
{ PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET, "sent layoutget" })
{ PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET, "sent layoutget" }, \
{ PNFS_UPDATE_LAYOUT_EXIT, "exit" })
TRACE_EVENT(pnfs_update_layout,
TP_PROTO(struct inode *inode,
@ -1845,6 +1847,78 @@ TRACE_EVENT(pnfs_update_layout,
)
);
DECLARE_EVENT_CLASS(pnfs_layout_event,
TP_PROTO(struct inode *inode,
loff_t pos,
u64 count,
enum pnfs_iomode iomode,
struct pnfs_layout_hdr *lo,
struct pnfs_layout_segment *lseg
),
TP_ARGS(inode, pos, count, iomode, lo, lseg),
TP_STRUCT__entry(
__field(dev_t, dev)
__field(u64, fileid)
__field(u32, fhandle)
__field(loff_t, pos)
__field(u64, count)
__field(enum pnfs_iomode, iomode)
__field(int, layoutstateid_seq)
__field(u32, layoutstateid_hash)
__field(long, lseg)
),
TP_fast_assign(
__entry->dev = inode->i_sb->s_dev;
__entry->fileid = NFS_FILEID(inode);
__entry->fhandle = nfs_fhandle_hash(NFS_FH(inode));
__entry->pos = pos;
__entry->count = count;
__entry->iomode = iomode;
if (lo != NULL) {
__entry->layoutstateid_seq =
be32_to_cpu(lo->plh_stateid.seqid);
__entry->layoutstateid_hash =
nfs_stateid_hash(&lo->plh_stateid);
} else {
__entry->layoutstateid_seq = 0;
__entry->layoutstateid_hash = 0;
}
__entry->lseg = (long)lseg;
),
TP_printk(
"fileid=%02x:%02x:%llu fhandle=0x%08x "
"iomode=%s pos=%llu count=%llu "
"layoutstateid=%d:0x%08x lseg=0x%lx",
MAJOR(__entry->dev), MINOR(__entry->dev),
(unsigned long long)__entry->fileid,
__entry->fhandle,
show_pnfs_iomode(__entry->iomode),
(unsigned long long)__entry->pos,
(unsigned long long)__entry->count,
__entry->layoutstateid_seq, __entry->layoutstateid_hash,
__entry->lseg
)
);
#define DEFINE_PNFS_LAYOUT_EVENT(name) \
DEFINE_EVENT(pnfs_layout_event, name, \
TP_PROTO(struct inode *inode, \
loff_t pos, \
u64 count, \
enum pnfs_iomode iomode, \
struct pnfs_layout_hdr *lo, \
struct pnfs_layout_segment *lseg \
), \
TP_ARGS(inode, pos, count, iomode, lo, lseg))
DEFINE_PNFS_LAYOUT_EVENT(pnfs_mds_fallback_pg_init_read);
DEFINE_PNFS_LAYOUT_EVENT(pnfs_mds_fallback_pg_init_write);
DEFINE_PNFS_LAYOUT_EVENT(pnfs_mds_fallback_pg_get_mirror_count);
DEFINE_PNFS_LAYOUT_EVENT(pnfs_mds_fallback_read_done);
DEFINE_PNFS_LAYOUT_EVENT(pnfs_mds_fallback_write_done);
DEFINE_PNFS_LAYOUT_EVENT(pnfs_mds_fallback_read_pagelist);
DEFINE_PNFS_LAYOUT_EVENT(pnfs_mds_fallback_write_pagelist);
#endif /* CONFIG_NFS_V4_1 */
#endif /* _TRACE_NFS4_H */

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@ -2037,6 +2037,8 @@ pnfs_update_layout(struct inode *ino,
out_put_layout_hdr:
if (first)
pnfs_clear_first_layoutget(lo);
trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
PNFS_UPDATE_LAYOUT_EXIT);
pnfs_put_layout_hdr(lo);
out:
dprintk("%s: inode %s/%llu pNFS layout segment %s for "

View File

@ -660,6 +660,7 @@ enum pnfs_update_layout_reason {
PNFS_UPDATE_LAYOUT_BLOCKED,
PNFS_UPDATE_LAYOUT_INVALID_OPEN,
PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET,
PNFS_UPDATE_LAYOUT_EXIT,
};
#define NFS4_OP_MAP_NUM_LONGS \