Re: [PATCH 08/12] iomap: lift the xfs readpage / readpages tracing to iomap

Darrick J. Wong
2019-10-15T18:08:41Z

On Tue, Oct 15, 2019 at 05:43:41PM +0200, Christoph Hellwig wrote:
> Lift the xfs code for tracing address space operations to the iomap
> layer.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks ok,
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

--D

> ---
> fs/iomap/Makefile | 16 ++++++++------
> fs/iomap/buffered-io.c | 5 +++++
> fs/iomap/trace.c | 12 +++++++++++
> fs/iomap/trace.h | 49 ++++++++++++++++++++++++++++++++++++++++++
> fs/xfs/xfs_aops.c | 2 --
> fs/xfs/xfs_trace.h | 26 ----------------------
> 6 files changed, 75 insertions(+), 35 deletions(-)
> create mode 100644 fs/iomap/trace.c
> create mode 100644 fs/iomap/trace.h
>
> diff --git a/fs/iomap/Makefile b/fs/iomap/Makefile
> index 93cd11938bf5..eef2722d93a1 100644
> --- a/fs/iomap/Makefile
> +++ b/fs/iomap/Makefile
> @@ -3,13 +3,15 @@
> # Copyright (c) 2019 Oracle.
> # All Rights Reserved.
> #
> -obj-$(CONFIG_FS_IOMAP) += iomap.o
>
> -iomap-y += \
> - apply.o \
> - buffered-io.o \
> - direct-io.o \
> - fiemap.o \
> - seek.o
> +ccflags-y += -I $(srctree)/$(src) # needed for trace events
> +
> +obj-$(CONFIG_FS_IOMAP) += iomap.o
>
> +iomap-y += trace.o \
> + apply.o \
> + buffered-io.o \
> + direct-io.o \
> + fiemap.o \
> + seek.o
> iomap-$(CONFIG_SWAP) += swapfile.o
> diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
> index 181ee8477aad..d1620c3f2a4c 100644
> --- a/fs/iomap/buffered-io.c
> +++ b/fs/iomap/buffered-io.c
> @@ -16,6 +16,7 @@
> #include <linux/bio.h>
> #include <linux/sched/signal.h>
> #include <linux/migrate.h>
> +#include "trace.h"
>
> #include "../internal.h"
>
> @@ -301,6 +302,8 @@ iomap_readpage(struct page *page, const struct iomap_ops *ops)
> unsigned poff;
> loff_t ret;
>
> + trace_iomap_readpage(page->mapping->host, 1);
> +
> for (poff = 0; poff < PAGE_SIZE; poff += ret) {
> ret = iomap_apply(inode, page_offset(page) + poff,
> PAGE_SIZE - poff, 0, ops, &ctx,
> @@ -397,6 +400,8 @@ iomap_readpages(struct address_space *mapping, struct list_head *pages,
> loff_t last = page_offset(list_entry(pages->next, struct page, lru));
> loff_t length = last - pos + PAGE_SIZE, ret = 0;
>
> + trace_iomap_readpages(mapping->host, nr_pages);
> +
> while (length > 0) {
> ret = iomap_apply(mapping->host, pos, length, 0, ops,
> &ctx, iomap_readpages_actor);
> diff --git a/fs/iomap/trace.c b/fs/iomap/trace.c
> new file mode 100644
> index 000000000000..63ce9f0ce4dc
> --- /dev/null
> +++ b/fs/iomap/trace.c
> @@ -0,0 +1,12 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2019, Christoph Hellwig
> + */
> +#include <linux/iomap.h>
> +
> +/*
> + * We include this last to have the helpers above available for the trace
> + * event implementations.
> + */
> +#define CREATE_TRACE_POINTS
> +#include "trace.h"
> diff --git a/fs/iomap/trace.h b/fs/iomap/trace.h
> new file mode 100644
> index 000000000000..3900de1d871d
> --- /dev/null
> +++ b/fs/iomap/trace.h
> @@ -0,0 +1,49 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2009-2019, Christoph Hellwig
> + *
> + * NOTE: none of these tracepoints shall be consider a stable kernel ABI
> + * as they can change at any time.
> + */
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM iomap
> +
> +#if !defined(_IOMAP_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _IOMAP_TRACE_H
> +
> +#include <linux/tracepoint.h>
> +
> +struct inode;
> +
> +DECLARE_EVENT_CLASS(iomap_readpage_class,
> + TP_PROTO(struct inode *inode, int nr_pages),
> + TP_ARGS(inode, nr_pages),
> + TP_STRUCT__entry(
> + __field(dev_t, dev)
> + __field(u64, ino)
> + __field(int, nr_pages)
> + ),
> + TP_fast_assign(
> + __entry->dev = inode->i_sb->s_dev;
> + __entry->ino = inode->i_ino;
> + __entry->nr_pages = nr_pages;
> + ),
> + TP_printk("dev %d:%d ino 0x%llx nr_pages %d",
> + MAJOR(__entry->dev), MINOR(__entry->dev),
> + __entry->ino,
> + __entry->nr_pages)
> +)
> +
> +#define DEFINE_READPAGE_EVENT(name) \
> +DEFINE_EVENT(iomap_readpage_class, name, \
> + TP_PROTO(struct inode *inode, int nr_pages), \
> + TP_ARGS(inode, nr_pages))
> +DEFINE_READPAGE_EVENT(iomap_readpage);
> +DEFINE_READPAGE_EVENT(iomap_readpages);
> +
> +#endif /* _IOMAP_TRACE_H */
> +
> +#undef TRACE_INCLUDE_PATH
> +#define TRACE_INCLUDE_PATH .
> +#define TRACE_INCLUDE_FILE trace
> +#include <trace/define_trace.h>
> diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
> index 00fe40b35f72..e2033b070f4a 100644
> --- a/fs/xfs/xfs_aops.c
> +++ b/fs/xfs/xfs_aops.c
> @@ -1184,7 +1184,6 @@ xfs_vm_readpage(
> struct file *unused,
> struct page *page)
> {
> - trace_xfs_vm_readpage(page->mapping->host, 1);
> return iomap_readpage(page, &xfs_iomap_ops);
> }
>
> @@ -1195,7 +1194,6 @@ xfs_vm_readpages(
> struct list_head *pages,
> unsigned nr_pages)
> {
> - trace_xfs_vm_readpages(mapping->host, nr_pages);
> return iomap_readpages(mapping, pages, nr_pages, &xfs_iomap_ops);
> }
>
> diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
> index eaae275ed430..eae4b29c174e 100644
> --- a/fs/xfs/xfs_trace.h
> +++ b/fs/xfs/xfs_trace.h
> @@ -1197,32 +1197,6 @@ DEFINE_PAGE_EVENT(xfs_writepage);
> DEFINE_PAGE_EVENT(xfs_releasepage);
> DEFINE_PAGE_EVENT(xfs_invalidatepage);
>
> -DECLARE_EVENT_CLASS(xfs_readpage_class,
> - TP_PROTO(struct inode *inode, int nr_pages),
> - TP_ARGS(inode, nr_pages),
> - TP_STRUCT__entry(
> - __field(dev_t, dev)
> - __field(xfs_ino_t, ino)
> - __field(int, nr_pages)
> - ),
> - TP_fast_assign(
> - __entry->dev = inode->i_sb->s_dev;
> - __entry->ino = inode->i_ino;
> - __entry->nr_pages = nr_pages;
> - ),
> - TP_printk("dev %d:%d ino 0x%llx nr_pages %d",
> - MAJOR(__entry->dev), MINOR(__entry->dev),
> - __entry->ino,
> - __entry->nr_pages)
> -)
> -
> -#define DEFINE_READPAGE_EVENT(name) \
> -DEFINE_EVENT(xfs_readpage_class, name, \
> - TP_PROTO(struct inode *inode, int nr_pages), \
> - TP_ARGS(inode, nr_pages))
> -DEFINE_READPAGE_EVENT(xfs_vm_readpage);
> -DEFINE_READPAGE_EVENT(xfs_vm_readpages);
> -
> DECLARE_EVENT_CLASS(xfs_imap_class,
> TP_PROTO(struct xfs_inode *ip, xfs_off_t offset, ssize_t count,
> int whichfork, struct xfs_bmbt_irec *irec),
> --
> 2.20.1
>