[PATCH v2 3/6] locks: sprinkle some tracepoints around the file locking code
From: Jeff Layton
Date: Fri Jan 08 2016 - 08:51:40 EST
Add some tracepoints around the POSIX locking code. These were useful
when tracking down problems when handling the race between setlk and
close.
Signed-off-by: Jeff Layton <jeff.layton@xxxxxxxxxxxxxxx>
---
fs/locks.c | 12 +++++--
include/trace/events/filelock.h | 77 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 86 insertions(+), 3 deletions(-)
diff --git a/fs/locks.c b/fs/locks.c
index e72077d5a664..0af2387bd91e 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -229,6 +229,7 @@ locks_get_lock_context(struct inode *inode, int type)
ctx = smp_load_acquire(&inode->i_flctx);
}
out:
+ trace_locks_get_lock_context(inode, type, ctx);
return ctx;
}
@@ -1141,6 +1142,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
if (new_fl2)
locks_free_lock(new_fl2);
locks_dispose_list(&dispose);
+ trace_posix_lock_inode(inode, request, error);
+
return error;
}
@@ -2164,6 +2167,8 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
if (file_lock == NULL)
return -ENOLCK;
+ inode = file_inode(filp);
+
/*
* This might block, so we do it before checking the inode.
*/
@@ -2171,8 +2176,6 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
if (copy_from_user(&flock, l, sizeof(flock)))
goto out;
- inode = file_inode(filp);
-
/* Don't allow mandatory locks on files that may be memory mapped
* and shared.
*/
@@ -2241,6 +2244,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
}
}
out:
+ trace_fcntl_setlk(inode, file_lock, error);
locks_free_lock(file_lock);
return error;
}
@@ -2397,6 +2401,7 @@ out:
*/
void locks_remove_posix(struct file *filp, fl_owner_t owner)
{
+ int error;
struct file_lock lock;
struct file_lock_context *ctx;
@@ -2419,10 +2424,11 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner)
lock.fl_ops = NULL;
lock.fl_lmops = NULL;
- vfs_lock_file(filp, F_SETLK, &lock, NULL);
+ error = vfs_lock_file(filp, F_SETLK, &lock, NULL);
if (lock.fl_ops && lock.fl_ops->fl_release_private)
lock.fl_ops->fl_release_private(&lock);
+ trace_locks_remove_posix(file_inode(filp), &lock, error);
}
EXPORT_SYMBOL(locks_remove_posix);
diff --git a/include/trace/events/filelock.h b/include/trace/events/filelock.h
index c72f2dc01d0b..63a7680347cb 100644
--- a/include/trace/events/filelock.h
+++ b/include/trace/events/filelock.h
@@ -34,6 +34,83 @@
{ F_WRLCK, "F_WRLCK" }, \
{ F_UNLCK, "F_UNLCK" })
+TRACE_EVENT(locks_get_lock_context,
+ TP_PROTO(struct inode *inode, int type, struct file_lock_context *ctx),
+
+ TP_ARGS(inode, type, ctx),
+
+ TP_STRUCT__entry(
+ __field(unsigned long, i_ino)
+ __field(dev_t, s_dev)
+ __field(unsigned char, type)
+ __field(struct file_lock_context *, ctx)
+ ),
+
+ TP_fast_assign(
+ __entry->s_dev = inode->i_sb->s_dev;
+ __entry->i_ino = inode->i_ino;
+ __entry->type = type;
+ __entry->ctx = ctx;
+ ),
+
+ TP_printk("dev=0x%x:0x%x ino=0x%lx type=%s ctx=%p",
+ MAJOR(__entry->s_dev), MINOR(__entry->s_dev),
+ __entry->i_ino, show_fl_type(__entry->type), __entry->ctx)
+);
+
+DECLARE_EVENT_CLASS(filelock_lock,
+ TP_PROTO(struct inode *inode, struct file_lock *fl, int ret),
+
+ TP_ARGS(inode, fl, ret),
+
+ TP_STRUCT__entry(
+ __field(struct file_lock *, fl)
+ __field(unsigned long, i_ino)
+ __field(dev_t, s_dev)
+ __field(struct file_lock *, fl_next)
+ __field(fl_owner_t, fl_owner)
+ __field(unsigned int, fl_pid)
+ __field(unsigned int, fl_flags)
+ __field(unsigned char, fl_type)
+ __field(loff_t, fl_start)
+ __field(loff_t, fl_end)
+ __field(int, ret)
+ ),
+
+ TP_fast_assign(
+ __entry->fl = fl ? fl : NULL;
+ __entry->s_dev = inode->i_sb->s_dev;
+ __entry->i_ino = inode->i_ino;
+ __entry->fl_next = fl ? fl->fl_next : NULL;
+ __entry->fl_owner = fl ? fl->fl_owner : NULL;
+ __entry->fl_pid = fl ? fl->fl_pid : 0;
+ __entry->fl_flags = fl ? fl->fl_flags : 0;
+ __entry->fl_type = fl ? fl->fl_type : 0;
+ __entry->fl_start = fl ? fl->fl_start : 0;
+ __entry->fl_end = fl ? fl->fl_end : 0;
+ __entry->ret = ret;
+ ),
+
+ TP_printk("fl=0x%p dev=0x%x:0x%x ino=0x%lx fl_next=0x%p fl_owner=0x%p fl_pid=%u fl_flags=%s fl_type=%s fl_start=%lld fl_end=%lld ret=%d",
+ __entry->fl, MAJOR(__entry->s_dev), MINOR(__entry->s_dev),
+ __entry->i_ino, __entry->fl_next, __entry->fl_owner,
+ __entry->fl_pid, show_fl_flags(__entry->fl_flags),
+ show_fl_type(__entry->fl_type),
+ __entry->fl_start, __entry->fl_end, __entry->ret)
+);
+
+DEFINE_EVENT(filelock_lock, posix_lock_inode,
+ TP_PROTO(struct inode *inode, struct file_lock *fl, int ret),
+ TP_ARGS(inode, fl, ret));
+
+DEFINE_EVENT(filelock_lock, fcntl_setlk,
+ TP_PROTO(struct inode *inode, struct file_lock *fl, int ret),
+ TP_ARGS(inode, fl, ret));
+
+DEFINE_EVENT(filelock_lock, locks_remove_posix,
+ TP_PROTO(struct inode *inode, struct file_lock *fl, int ret),
+ TP_ARGS(inode, fl, ret));
+
DECLARE_EVENT_CLASS(filelock_lease,
TP_PROTO(struct inode *inode, struct file_lock *fl),
--
2.5.0