Fix: update writeback instrumentation for kernel 4.0+

Introduced by Linux kernel commit:

commit 0ae45f63d4ef8d8eeec49c7d8b44a1775fff13e8
Author: Theodore Ts'o <tytso@mit.edu>
Date:   Mon Feb 2 00:37:00 2015 -0500

    vfs: add support for a lazytime mount option

And:

commit de1414a654e66b81b5348dbc5259ecf2fb61655e
Author: Christoph Hellwig <hch@lst.de>
Date:   Wed Jan 14 10:42:36 2015 +0100

    fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/instrumentation/events/lttng-module/writeback.h b/instrumentation/events/lttng-module/writeback.h
index a7657ed0e75bc04c9d2a94e85894cf3a4d039776..79f84b76559f92d72b3d34440c74c23205b900f3 100644 (file)
--- a/instrumentation/events/lttng-module/writeback.h
+++ b/instrumentation/events/lttng-module/writeback.h
@@ -12,6 +12,8 @@
 
 #ifndef _TRACE_WRITEBACK_DEF_
 #define _TRACE_WRITEBACK_DEF_
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(4,0,0))
 static inline struct backing_dev_info *inode_to_bdi(struct inode *inode)
 {
        struct super_block *sb = inode->i_sb;
@@ -21,8 +23,26 @@ static inline struct backing_dev_info *inode_to_bdi(struct inode *inode)
 
        return sb->s_bdi;
 }
+#endif /* #if (LINUX_VERSION_CODE < KERNEL_VERSION(4,0,0)) */
+
 #endif
 
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,0,0))
+#define show_inode_state(state)                                        \
+       __print_flags(state, "|",                               \
+               {I_DIRTY_SYNC,          "I_DIRTY_SYNC"},        \
+               {I_DIRTY_DATASYNC,      "I_DIRTY_DATASYNC"},    \
+               {I_DIRTY_PAGES,         "I_DIRTY_PAGES"},       \
+               {I_NEW,                 "I_NEW"},               \
+               {I_WILL_FREE,           "I_WILL_FREE"},         \
+               {I_FREEING,             "I_FREEING"},           \
+               {I_CLEAR,               "I_CLEAR"},             \
+               {I_SYNC,                "I_SYNC"},              \
+               {I_DIRTY_TIME,          "I_DIRTY_TIME"},        \
+               {I_DIRTY_TIME_EXPIRED,  "I_DIRTY_TIME_EXPIRED"}, \
+               {I_REFERENCED,          "I_REFERENCED"}         \
+       )
+#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,0,0)) */
 #define show_inode_state(state)                                        \
        __print_flags(state, "|",                               \
                {I_DIRTY_SYNC,          "I_DIRTY_SYNC"},        \
@@ -35,6 +55,7 @@ static inline struct backing_dev_info *inode_to_bdi(struct inode *inode)
                {I_SYNC,                "I_SYNC"},              \
                {I_REFERENCED,          "I_REFERENCED"}         \
        )
+#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,0,0)) */
 
 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0))
 #define WB_WORK_REASON                                                 \
@@ -48,7 +69,91 @@ static inline struct backing_dev_info *inode_to_bdi(struct inode *inode)
                {WB_REASON_FORKER_THREAD,       "forker_thread"}
 #endif
 
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,9,0))
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,0,0))
+
+LTTNG_TRACEPOINT_EVENT(writeback_dirty_page,
+       TP_PROTO(struct page *page, struct address_space *mapping),
+       TP_ARGS(page, mapping),
+       TP_STRUCT__entry (
+               __array_text(char, name, 32)
+               __field(unsigned long, ino)
+               __field(pgoff_t, index)
+       ),
+       TP_fast_assign(
+               tp_memcpy(name,
+                       mapping ? dev_name(inode_to_bdi(mapping->host)->dev) : "(unknown)", 32)
+               tp_assign(ino, mapping ? mapping->host->i_ino : 0)
+               tp_assign(index, page->index)
+       ),
+       TP_printk("bdi %s: ino=%lu index=%lu",
+               __entry->name,
+               __entry->ino,
+               __entry->index
+       )
+)
+
+LTTNG_TRACEPOINT_EVENT_CLASS(writeback_dirty_inode_template,
+       TP_PROTO(struct inode *inode, int flags),
+       TP_ARGS(inode, flags),
+       TP_STRUCT__entry (
+               __array_text(char, name, 32)
+               __field(unsigned long, ino)
+               __field(unsigned long, state)
+               __field(unsigned long, flags)
+       ),
+       TP_fast_assign(
+               /* may be called for files on pseudo FSes w/ unregistered bdi */
+               tp_memcpy(name,
+                       inode_to_bdi(inode)->dev ?
+                               dev_name(inode_to_bdi(inode)->dev) : "(unknown)", 32)
+               tp_assign(ino, inode->i_ino)
+               tp_assign(state, inode->i_state)
+               tp_assign(flags, flags)
+       ),
+       TP_printk("bdi %s: ino=%lu flags=%s",
+               __entry->name,
+               __entry->ino,
+               show_inode_state(__entry->flags)
+       )
+)
+#define LTTNG_TRACEPOINT_EVENT_WRITEBACK_DIRTY_INODE_TEMPLATE(name) \
+LTTNG_TRACEPOINT_EVENT_INSTANCE(writeback_dirty_inode_template, name, \
+       TP_PROTO(struct inode *inode, int flags), \
+       TP_ARGS(inode, flags))
+LTTNG_TRACEPOINT_EVENT_WRITEBACK_DIRTY_INODE_TEMPLATE(writeback_dirty_inode_start)
+LTTNG_TRACEPOINT_EVENT_WRITEBACK_DIRTY_INODE_TEMPLATE(writeback_dirty_inode)
+LTTNG_TRACEPOINT_EVENT_WRITEBACK_DIRTY_INODE_TEMPLATE(writeback_mark_inode_dirty)
+
+LTTNG_TRACEPOINT_EVENT_CLASS(writeback_write_inode_template,
+       TP_PROTO(struct inode *inode, struct writeback_control *wbc),
+       TP_ARGS(inode, wbc),
+       TP_STRUCT__entry (
+               __array_text(char, name, 32)
+               __field(unsigned long, ino)
+               __field(int, sync_mode)
+       ),
+       TP_fast_assign(
+               tp_memcpy(name,
+                       dev_name(inode_to_bdi(inode)->dev), 32)
+               tp_assign(ino, inode->i_ino)
+               tp_assign(sync_mode, wbc->sync_mode)
+       ),
+       TP_printk("bdi %s: ino=%lu sync_mode=%d",
+               __entry->name,
+               __entry->ino,
+               __entry->sync_mode
+       )
+)
+
+#define LTTNG_TRACEPOINT_EVENT_WRITEBACK_WRITE_INODE(name) \
+LTTNG_TRACEPOINT_EVENT_INSTANCE(writeback_write_inode_template, name, \
+       TP_PROTO(struct inode *inode, struct writeback_control *wbc), \
+       TP_ARGS(inode, wbc))
+LTTNG_TRACEPOINT_EVENT_WRITEBACK_WRITE_INODE(writeback_write_inode_start)
+LTTNG_TRACEPOINT_EVENT_WRITEBACK_WRITE_INODE(writeback_write_inode)
+
+#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(3,9,0))
+
 LTTNG_TRACEPOINT_EVENT(writeback_dirty_page,
        TP_PROTO(struct page *page, struct address_space *mapping),
        TP_ARGS(page, mapping),
@@ -126,8 +231,28 @@ LTTNG_TRACEPOINT_EVENT_INSTANCE(writeback_write_inode_template, name, \
        TP_ARGS(inode, wbc))
 LTTNG_TRACEPOINT_EVENT_WRITEBACK_WRITE_INODE(writeback_write_inode_start)
 LTTNG_TRACEPOINT_EVENT_WRITEBACK_WRITE_INODE(writeback_write_inode)
+
 #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,9,0)) */
 
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,0,0))
+
+LTTNG_TRACEPOINT_EVENT_CLASS(writeback_work_class,
+       TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work),
+       TP_ARGS(bdi, work),
+       TP_STRUCT__entry(
+               __array_text(char, name, 32)
+       ),
+       TP_fast_assign(
+               tp_memcpy(name, bdi->dev ? dev_name(bdi->dev) :
+                               "(unknown)", 32)
+       ),
+       TP_printk("bdi %s",
+                 __entry->name
+       )
+)
+
+#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,0,0)) */
+
 LTTNG_TRACEPOINT_EVENT_CLASS(writeback_work_class,
        TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work),
        TP_ARGS(bdi, work),
@@ -142,6 +267,9 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_work_class,
                  __entry->name
        )
 )
+
+#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,0,0)) */
+
 #define LTTNG_TRACEPOINT_EVENT_WRITEBACK_WORK_INSTANCE(name) \
 LTTNG_TRACEPOINT_EVENT_INSTANCE(writeback_work_class, name, \
        TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work), \