This patch adds the trace point to ext2 direct-io apis
in fs/ext2/file.c
Here is how the output looks like
a.out-467865 [006] 6758.170968: ext2_dio_write_begin: dev 7:12 ino 0xe isize 0x1000 pos 0x0 len 4096 flags DIRECT|WRITE aio 1 ret 0
a.out-467865 [006] 6758.171061: ext2_dio_write_end: dev 7:12 ino 0xe isize 0x1000 pos 0x0 len 0 flags DIRECT|WRITE aio 1 ret -529
kworker/3:153-444162 [003] 6758.171252: ext2_dio_write_endio: dev 7:12 ino 0xe isize 0x1000 pos 0x0 len 4096 flags DIRECT|WRITE aio 1 ret 0
a.out-468222 [001] 6761.628924: ext2_dio_read_begin: dev 7:12 ino 0xe isize 0x1000 pos 0x0 len 4096 flags DIRECT aio 1 ret 0
a.out-468222 [001] 6761.629063: ext2_dio_read_end: dev 7:12 ino 0xe isize 0x1000 pos 0x0 len 0 flags DIRECT aio 1 ret -529
a.out-468428 [005] 6763.937454: ext2_dio_write_begin: dev 7:12 ino 0xe isize 0x1000 pos 0x0 len 4096 flags DIRECT aio 0 ret 0
a.out-468428 [005] 6763.937829: ext2_dio_write_endio: dev 7:12 ino 0xe isize 0x1000 pos 0x0 len 4096 flags DIRECT aio 0 ret 0
a.out-468428 [005] 6763.937847: ext2_dio_write_end: dev 7:12 ino 0xe isize 0x1000 pos 0x1000 len 0 flags DIRECT aio 0 ret 4096
a.out-468609 [000] 6765.702878: ext2_dio_read_begin: dev 7:12 ino 0xe isize 0x1000 pos 0x0 len 4096 flags DIRECT aio 0 ret 0
a.out-468609 [000] 6765.703243: ext2_dio_read_end: dev 7:12 ino 0xe isize 0x1000 pos 0x1000 len 0 flags DIRECT aio 0 ret 4096
Reported-and-tested-by: Disha Goel <disgoel@xxxxxxxxxxxxx>
[Need to add CFLAGS_trace for fixing unable to find trace file problem]
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
---
fs/ext2/Makefile | 5 ++-
fs/ext2/file.c | 10 +++++-
fs/ext2/trace.c | 6 ++++
fs/ext2/trace.h | 94 ++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 113 insertions(+), 2 deletions(-)
create mode 100644 fs/ext2/trace.c
create mode 100644 fs/ext2/trace.h
diff --git a/fs/ext2/Makefile b/fs/ext2/Makefile
index 311479d864a7..8860948ef9ca 100644
--- a/fs/ext2/Makefile
+++ b/fs/ext2/Makefile
@@ -6,7 +6,10 @@
obj-$(CONFIG_EXT2_FS) += ext2.o
ext2-y := balloc.o dir.o file.o ialloc.o inode.o \
- ioctl.o namei.o super.o symlink.o
+ ioctl.o namei.o super.o symlink.o trace.o
+
+# For tracepoints to include our trace.h from tracepoint infrastructure
+CFLAGS_trace.o := -I$(src)
ext2-$(CONFIG_EXT2_FS_XATTR) += xattr.o xattr_user.o xattr_trusted.o
ext2-$(CONFIG_EXT2_FS_POSIX_ACL) += acl.o
diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index 98add36c1a59..7a32f202908e 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -29,6 +29,7 @@
#include "ext2.h"
#include "xattr.h"
#include "acl.h"
+#include "trace.h"
#ifdef CONFIG_FS_DAX
static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
@@ -168,9 +169,11 @@ static ssize_t ext2_dio_read_iter(struct kiocb *iocb, struct iov_iter *to)
struct inode *inode = file->f_mapping->host;
ssize_t ret;
+ trace_ext2_dio_read_begin(iocb, to, 0);
inode_lock_shared(inode);
ret = iomap_dio_rw(iocb, to, &ext2_iomap_ops, NULL, 0, NULL, 0);
inode_unlock_shared(inode);
+ trace_ext2_dio_read_end(iocb, to, ret);
return ret;
}
@@ -198,6 +201,7 @@ static int ext2_dio_write_end_io(struct kiocb *iocb, ssize_t size,
mark_inode_dirty(inode);
}
out:
+ trace_ext2_dio_write_endio(iocb, size, error);
return error;
}
@@ -214,7 +218,9 @@ static ssize_t ext2_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
unsigned long blocksize = inode->i_sb->s_blocksize;
loff_t offset = iocb->ki_pos;
loff_t count = iov_iter_count(from);
+ ssize_t status = 0;
+ trace_ext2_dio_write_begin(iocb, from, 0);
inode_lock(inode);
ret = generic_write_checks(iocb, from);
if (ret <= 0)
@@ -242,7 +248,6 @@ static ssize_t ext2_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
/* handle case for partial write and for fallback to buffered write */
if (ret >= 0 && iov_iter_count(from)) {
loff_t pos, endbyte;
- ssize_t status;
int ret2;
iocb->ki_flags &= ~IOCB_DIRECT;
@@ -268,6 +273,9 @@ static ssize_t ext2_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
out_unlock:
inode_unlock(inode);
+ if (status)
+ trace_ext2_dio_write_buff_end(iocb, from, status);
+ trace_ext2_dio_write_end(iocb, from, ret);
return ret;
}
diff --git a/fs/ext2/trace.c b/fs/ext2/trace.c
new file mode 100644
index 000000000000..b01cdf6526fd
--- /dev/null
+++ b/fs/ext2/trace.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "ext2.h"
+#include <linux/uio.h>
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
diff --git a/fs/ext2/trace.h b/fs/ext2/trace.h
new file mode 100644
index 000000000000..7d230e13576e
--- /dev/null
+++ b/fs/ext2/trace.h
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM ext2
+
+#if !defined(_EXT2_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _EXT2_TRACE_H
+
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(ext2_dio_class,
+ TP_PROTO(struct kiocb *iocb, struct iov_iter *iter, ssize_t ret),
+ TP_ARGS(iocb, iter, ret),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(ino_t, ino)
+ __field(loff_t, isize)
+ __field(loff_t, pos)
+ __field(size_t, count)
+ __field(int, ki_flags)
+ __field(bool, aio)
+ __field(ssize_t, ret)
+ ),
+ TP_fast_assign(
+ __entry->dev = file_inode(iocb->ki_filp)->i_sb->s_dev;
+ __entry->ino = file_inode(iocb->ki_filp)->i_ino;
+ __entry->isize = file_inode(iocb->ki_filp)->i_size;
+ __entry->pos = iocb->ki_pos;
+ __entry->count = iov_iter_count(iter);
+ __entry->ki_flags = iocb->ki_flags;
+ __entry->aio = !is_sync_kiocb(iocb);
+ __entry->ret = ret;
+ ),
+ TP_printk("dev %d:%d ino 0x%lx isize 0x%llx pos 0x%llx len %zu flags %s aio %d ret %zd",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->ino,
+ __entry->isize,
+ __entry->pos,
+ __entry->count,
+ __print_flags(__entry->ki_flags, "|", TRACE_IOCB_STRINGS),
+ __entry->aio,
+ __entry->ret)
+);
+
+#define DEFINE_DIO_RW_EVENT(name) \
+DEFINE_EVENT(ext2_dio_class, name, \
+ TP_PROTO(struct kiocb *iocb, struct iov_iter *iter, ssize_t ret), \
+ TP_ARGS(iocb, iter, ret))
+DEFINE_DIO_RW_EVENT(ext2_dio_write_begin);
+DEFINE_DIO_RW_EVENT(ext2_dio_write_end);
+DEFINE_DIO_RW_EVENT(ext2_dio_write_buff_end);
+DEFINE_DIO_RW_EVENT(ext2_dio_read_begin);
+DEFINE_DIO_RW_EVENT(ext2_dio_read_end);
+
+TRACE_EVENT(ext2_dio_write_endio,
+ TP_PROTO(struct kiocb *iocb, ssize_t size, int ret),
+ TP_ARGS(iocb, size, ret),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(ino_t, ino)
+ __field(loff_t, isize)
+ __field(loff_t, pos)
+ __field(ssize_t, size)
+ __field(int, ki_flags)
+ __field(bool, aio)
+ __field(int, ret)
+ ),
+ TP_fast_assign(
+ __entry->dev = file_inode(iocb->ki_filp)->i_sb->s_dev;
+ __entry->ino = file_inode(iocb->ki_filp)->i_ino;
+ __entry->isize = file_inode(iocb->ki_filp)->i_size;
+ __entry->pos = iocb->ki_pos;
+ __entry->size = size;
+ __entry->ki_flags = iocb->ki_flags;
+ __entry->aio = !is_sync_kiocb(iocb);
+ __entry->ret = ret;
+ ),
+ TP_printk("dev %d:%d ino 0x%lx isize 0x%llx pos 0x%llx len %zd flags %s aio %d ret %d",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->ino,
+ __entry->isize,
+ __entry->pos,
+ __entry->size,
+ __print_flags(__entry->ki_flags, "|", TRACE_IOCB_STRINGS),
+ __entry->aio,
+ __entry->ret)
+);
+
+#endif /* _EXT2_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE trace
+#include <trace/define_trace.h>
--
2.39.2
