On Fri, Apr 21, 2023 at 03:16:19PM +0530, Ritesh Harjani (IBM) wrote:
> Add trace_iomap_dio_rw_begin, trace_iomap_dio_rw_queued and
> trace_iomap_dio_complete tracepoint.
> trace_iomap_dio_rw_queued is mostly only to know that the request was
> queued and -EIOCBQUEUED was returned. It is mostly trace_iomap_dio_rw_begin
> & trace_iomap_dio_complete which has all the details.
>
> <example output log>
> a.out-2073 [006] 134.225717: iomap_dio_rw_begin: dev 7:7 ino 0xe size 0x0 offset 0x0 length 0x1000 done_before 0x0 flags DIRECT|WRITE dio_flags DIO_FORCE_WAIT aio 1
> a.out-2073 [006] 134.226234: iomap_dio_complete: dev 7:7 ino 0xe size 0x1000 offset 0x1000 flags DIRECT|WRITE aio 1 error 0 ret 4096
> a.out-2074 [006] 136.225975: iomap_dio_rw_begin: dev 7:7 ino 0xe size 0x1000 offset 0x0 length 0x1000 done_before 0x0 flags DIRECT dio_flags aio 1
> a.out-2074 [006] 136.226173: iomap_dio_rw_queued: dev 7:7 ino 0xe size 0x1000 offset 0x1000 length 0x0
> ksoftirqd/3-31 [003] 136.226389: iomap_dio_complete: dev 7:7 ino 0xe size 0x1000 offset 0x1000 flags DIRECT aio 1 error 0 ret 4096
> a.out-2075 [003] 141.674969: iomap_dio_rw_begin: dev 7:7 ino 0xe size 0x1000 offset 0x0 length 0x1000 done_before 0x0 flags DIRECT|WRITE dio_flags aio 1
> a.out-2075 [003] 141.676085: iomap_dio_rw_queued: dev 7:7 ino 0xe size 0x1000 offset 0x1000 length 0x0
> kworker/2:0-27 [002] 141.676432: iomap_dio_complete: dev 7:7 ino 0xe size 0x1000 offset 0x1000 flags DIRECT|WRITE aio 1 error 0 ret 4096
> a.out-2077 [006] 143.443746: iomap_dio_rw_begin: dev 7:7 ino 0xe size 0x1000 offset 0x0 length 0x1000 done_before 0x0 flags DIRECT dio_flags aio 1
> a.out-2077 [006] 143.443866: iomap_dio_rw_queued: dev 7:7 ino 0xe size 0x1000 offset 0x1000 length 0x0
> ksoftirqd/5-41 [005] 143.444134: iomap_dio_complete: dev 7:7 ino 0xe size 0x1000 offset 0x1000 flags DIRECT aio 1 error 0 ret 4096
> a.out-2078 [007] 146.716833: iomap_dio_rw_begin: dev 7:7 ino 0xe size 0x1000 offset 0x0 length 0x1000 done_before 0x0 flags DIRECT dio_flags aio 0
> a.out-2078 [007] 146.717639: iomap_dio_complete: dev 7:7 ino 0xe size 0x1000 offset 0x1000 flags DIRECT aio 0 error 0 ret 4096
> a.out-2079 [006] 148.972605: iomap_dio_rw_begin: dev 7:7 ino 0xe size 0x1000 offset 0x0 length 0x1000 done_before 0x0 flags DIRECT dio_flags aio 0
> a.out-2079 [006] 148.973099: iomap_dio_complete: dev 7:7 ino 0xe size 0x1000 offset 0x1000 flags DIRECT aio 0 error 0 ret 4096
>
> Reviewed-by: Christoph Hellwig <hch@xxxxxx>
> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
> ---
> fs/iomap/direct-io.c | 7 +++-
> fs/iomap/trace.c | 1 +
> fs/iomap/trace.h | 78 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 85 insertions(+), 1 deletion(-)
>
> diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
> index 36ab1152dbea..019cc87d0fb3 100644
> --- a/fs/iomap/direct-io.c
> +++ b/fs/iomap/direct-io.c
> @@ -130,6 +130,7 @@ ssize_t iomap_dio_complete(struct iomap_dio *dio)
> if (ret > 0)
> ret += dio->done_before;
>
> + trace_iomap_dio_complete(iocb, dio->error, ret);
> kfree(dio);
>
> return ret;
> @@ -493,6 +494,8 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
> struct blk_plug plug;
> struct iomap_dio *dio;
>
> + trace_iomap_dio_rw_begin(iocb, iter, dio_flags, done_before);
> +
> if (!iomi.len)
> return NULL;
>
> @@ -650,8 +653,10 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
> */
> dio->wait_for_completion = wait_for_completion;
> if (!atomic_dec_and_test(&dio->ref)) {
> - if (!wait_for_completion)
> + if (!wait_for_completion) {
> + trace_iomap_dio_rw_queued(inode, iomi.pos, iomi.len);
> return ERR_PTR(-EIOCBQUEUED);
> + }
>
> for (;;) {
> set_current_state(TASK_UNINTERRUPTIBLE);
> diff --git a/fs/iomap/trace.c b/fs/iomap/trace.c
> index da217246b1a9..728d5443daf5 100644
> --- a/fs/iomap/trace.c
> +++ b/fs/iomap/trace.c
> @@ -3,6 +3,7 @@
> * Copyright (c) 2019 Christoph Hellwig
> */
> #include <linux/iomap.h>
> +#include <linux/uio.h>
>
> /*
> * We include this last to have the helpers above available for the trace
> diff --git a/fs/iomap/trace.h b/fs/iomap/trace.h
> index f6ea9540d082..448b82d16c0b 100644
> --- a/fs/iomap/trace.h
> +++ b/fs/iomap/trace.h
> @@ -83,6 +83,7 @@ DEFINE_RANGE_EVENT(iomap_writepage);
> DEFINE_RANGE_EVENT(iomap_release_folio);
> DEFINE_RANGE_EVENT(iomap_invalidate_folio);
> DEFINE_RANGE_EVENT(iomap_dio_invalidate_fail);
> +DEFINE_RANGE_EVENT(iomap_dio_rw_queued);
>
> #define IOMAP_TYPE_STRINGS \
> { IOMAP_HOLE, "HOLE" }, \
> @@ -107,6 +108,11 @@ DEFINE_RANGE_EVENT(iomap_dio_invalidate_fail);
> { IOMAP_F_BUFFER_HEAD, "BH" }, \
> { IOMAP_F_SIZE_CHANGED, "SIZE_CHANGED" }
>
> +#define IOMAP_DIO_STRINGS \
> + {IOMAP_DIO_FORCE_WAIT, "DIO_FORCE_WAIT" }, \
> + {IOMAP_DIO_OVERWRITE_ONLY, "DIO_OVERWRITE_ONLY" }, \
> + {IOMAP_DIO_PARTIAL, "DIO_PARTIAL" }
I'll fix these indentation ^ problems on commit.
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
--D
> +
> DECLARE_EVENT_CLASS(iomap_class,
> TP_PROTO(struct inode *inode, struct iomap *iomap),
> TP_ARGS(inode, iomap),
> @@ -183,6 +189,78 @@ TRACE_EVENT(iomap_iter,
> (void *)__entry->caller)
> );
>
> +TRACE_EVENT(iomap_dio_rw_begin,
> + TP_PROTO(struct kiocb *iocb, struct iov_iter *iter,
> + unsigned int dio_flags, size_t done_before),
> + TP_ARGS(iocb, iter, dio_flags, done_before),
> + TP_STRUCT__entry(
> + __field(dev_t, dev)
> + __field(ino_t, ino)
> + __field(loff_t, isize)
> + __field(loff_t, pos)
> + __field(size_t, count)
> + __field(size_t, done_before)
> + __field(int, ki_flags)
> + __field(unsigned int, dio_flags)
> + __field(bool, aio)
> + ),
> + 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->done_before = done_before;
> + __entry->ki_flags = iocb->ki_flags;
> + __entry->dio_flags = dio_flags;
> + __entry->aio = !is_sync_kiocb(iocb);
> + ),
> + TP_printk("dev %d:%d ino 0x%lx size 0x%llx offset 0x%llx length 0x%zx done_before 0x%zx flags %s dio_flags %s aio %d",
> + MAJOR(__entry->dev), MINOR(__entry->dev),
> + __entry->ino,
> + __entry->isize,
> + __entry->pos,
> + __entry->count,
> + __entry->done_before,
> + __print_flags(__entry->ki_flags, "|", TRACE_IOCB_STRINGS),
> + __print_flags(__entry->dio_flags, "|", IOMAP_DIO_STRINGS),
> + __entry->aio)
> +);
> +
> +TRACE_EVENT(iomap_dio_complete,
> + TP_PROTO(struct kiocb *iocb, int error, ssize_t ret),
> + TP_ARGS(iocb, error, ret),
> + TP_STRUCT__entry(
> + __field(dev_t, dev)
> + __field(ino_t, ino)
> + __field(loff_t, isize)
> + __field(loff_t, pos)
> + __field(int, ki_flags)
> + __field(bool, aio)
> + __field(int, error)
> + __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->ki_flags = iocb->ki_flags;
> + __entry->aio = !is_sync_kiocb(iocb);
> + __entry->error = error;
> + __entry->ret = ret;
> + ),
> + TP_printk("dev %d:%d ino 0x%lx size 0x%llx offset 0x%llx flags %s aio %d error %d ret %zd",
> + MAJOR(__entry->dev), MINOR(__entry->dev),
> + __entry->ino,
> + __entry->isize,
> + __entry->pos,
> + __print_flags(__entry->ki_flags, "|", TRACE_IOCB_STRINGS),
> + __entry->aio,
> + __entry->error,
> + __entry->ret)
> +);
> +
> #endif /* _IOMAP_TRACE_H */
>
> #undef TRACE_INCLUDE_PATH
> --
> 2.39.2
>
