dax: add tracepoints to dax_load_hole()
Add tracepoints to dax_load_hole(), following the same logging conventions
as the rest of DAX.
Here is the logging generated by a PTE read from a hole:
read-1075 [002] ....
62.362108: dax_pte_fault: dev 259:0 ino 0x1003 shared ALLOW_RETRY|KILLABLE|USER address 0x10480000 pgoff 0x280
read-1075 [002] ....
62.362140: dax_load_hole: dev 259:0 ino 0x1003 shared ALLOW_RETRY|KILLABLE|USER address 0x10480000 pgoff 0x280 NOPAGE
read-1075 [002] ....
62.362141: dax_pte_fault_done: dev 259:0 ino 0x1003 shared ALLOW_RETRY|KILLABLE|USER address 0x10480000 pgoff 0x280 NOPAGE
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ross Zwisler <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Steven Rostedt <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/fs/dax.c b/fs/dax.c
index d10524a..36fafff 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -509,21 +509,25 @@ int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
static int dax_load_hole(struct address_space *mapping, void **entry,
struct vm_fault *vmf)
{
+ struct inode *inode = mapping->host;
struct page *page;
int ret;
/* Hole page already exists? Return it... */
if (!radix_tree_exceptional_entry(*entry)) {
page = *entry;
- goto out;
+ goto finish_fault;
}
/* This will replace locked radix tree entry with a hole page */
page = find_or_create_page(mapping, vmf->pgoff,
vmf->gfp_mask | __GFP_ZERO);
- if (!page)
- return VM_FAULT_OOM;
- out:
+ if (!page) {
+ ret = VM_FAULT_OOM;
+ goto out;
+ }
+
+finish_fault:
vmf->page = page;
ret = finish_fault(vmf);
vmf->page = NULL;
@@ -531,8 +535,10 @@ static int dax_load_hole(struct address_space *mapping, void **entry,
if (!ret) {
/* Grab reference for PTE that is now referencing the page */
get_page(page);
- return VM_FAULT_NOPAGE;
+ ret = VM_FAULT_NOPAGE;
}
+out:
+ trace_dax_load_hole(inode, vmf, ret);
return ret;
}
