ANDROID: fs: FS tracepoints to track IO.

Adds tracepoints in ext4/f2fs/mpage to track readpages/buffered
write()s. This allows us to track files that are being read/written
to PIDs.

Change-Id: I26bd36f933108927d6903da04d8cb42fd9c3ef3d
Signed-off-by: Mohan Srinivasan <srmohan@google.com>
Git-commit: 32cbbe59538d2dd0b77822cc27ce32ca487c467d
Git-repo: https://android.googlesource.com/kernel/common/
[runminw@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Runmin Wang <runminw@codeaurora.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 99fa2fca52b1..0f465840dc29 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -45,6 +45,7 @@
 #include "ext4_ice.h"
 
 #include <trace/events/ext4.h>
+#include <trace/events/android_fs.h>
 
 #define MPAGE_DA_EXTENT_TAIL 0x01
 
@@ -1018,6 +1019,8 @@ static int ext4_write_begin(struct file *file, struct address_space *mapping,
 	pgoff_t index;
 	unsigned from, to;
 
+	trace_android_fs_datawrite_start(inode, pos, len,
+					 current->pid, current->comm);
 	trace_ext4_write_begin(inode, pos, len, flags);
 	/*
 	 * Reserve one block more for addition to orphan list in case
@@ -1154,6 +1157,7 @@ static int ext4_write_end(struct file *file,
 	int ret = 0, ret2;
 	int i_size_changed = 0;
 
+	trace_android_fs_datawrite_end(inode, pos, len);
 	trace_ext4_write_end(inode, pos, len, copied);
 	if (ext4_test_inode_state(inode, EXT4_STATE_ORDERED_MODE)) {
 		ret = ext4_jbd2_file_inode(handle, inode);
@@ -1267,6 +1271,7 @@ static int ext4_journalled_write_end(struct file *file,
 	unsigned from, to;
 	int size_changed = 0;
 
+	trace_android_fs_datawrite_end(inode, pos, len);
 	trace_ext4_journalled_write_end(inode, pos, len, copied);
 	from = pos & (PAGE_CACHE_SIZE - 1);
 	to = from + len;
@@ -2742,6 +2747,8 @@ static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
 					len, flags, pagep, fsdata);
 	}
 	*fsdata = (void *)0;
+	trace_android_fs_datawrite_start(inode, pos, len,
+					 current->pid, current->comm);
 	trace_ext4_da_write_begin(inode, pos, len, flags);
 
 	if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
@@ -2860,6 +2867,7 @@ static int ext4_da_write_end(struct file *file,
 		return ext4_write_end(file, mapping, pos,
 				      len, copied, page, fsdata);
 
+	trace_android_fs_datawrite_end(inode, pos, len);
 	trace_ext4_da_write_end(inode, pos, len, copied);
 	start = pos & (PAGE_CACHE_SIZE - 1);
 	end = start + copied - 1;
@@ -3352,12 +3360,31 @@ static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
 	if (ext4_has_inline_data(inode))
 		return 0;
 
+	if (trace_android_fs_dataread_start_enabled() &&
+	    (iov_iter_rw(iter) == READ))
+		trace_android_fs_dataread_start(inode, offset, count,
+						current->pid,
+						current->comm);
+	if (trace_android_fs_datawrite_start_enabled() &&
+	    (iov_iter_rw(iter) == WRITE))
+		trace_android_fs_datawrite_start(inode, offset, count,
+						 current->pid,
+						 current->comm);
+
 	trace_ext4_direct_IO_enter(inode, offset, count, iov_iter_rw(iter));
 	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
 		ret = ext4_ext_direct_IO(iocb, iter, offset);
 	else
 		ret = ext4_ind_direct_IO(iocb, iter, offset);
 	trace_ext4_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), ret);
+
+	if (trace_android_fs_dataread_start_enabled() &&
+	    (iov_iter_rw(iter) == READ))
+		trace_android_fs_dataread_end(inode, offset, count);
+	if (trace_android_fs_datawrite_start_enabled() &&
+	    (iov_iter_rw(iter) == WRITE))
+		trace_android_fs_datawrite_end(inode, offset, count);
+
 	return ret;
 }