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

Christoph Hellwig
2019-10-15T15:44:18Z

Lift the xfs code for tracing address space operations to the iomap
layer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
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