@@ -1132,13 +1132,16 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf,
int vmf_ret = 0;
void *entry;
+ trace_dax_pte_fault(inode, vmf, vmf_ret);
/*
* Check whether offset isn't beyond end of file now. Caller is supposed
* to hold locks serializing us with truncate / punch hole so this is
* a reliable test.
*/
- if (pos >= i_size_read(inode))
- return VM_FAULT_SIGBUS;
+ if (pos >= i_size_read(inode)) {
+ vmf_ret = VM_FAULT_SIGBUS;
+ goto out;
+ }
if ((vmf->flags & FAULT_FLAG_WRITE) && !vmf->cow_page)
flags |= IOMAP_WRITE;
@@ -1149,8 +1152,10 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf,
* that we never have to deal with more than a single extent here.
*/
error = ops->iomap_begin(inode, pos, PAGE_SIZE, flags, &iomap);
- if (error)
- return dax_fault_return(error);
+ if (error) {
+ vmf_ret = dax_fault_return(error);
+ goto out;
+ }
if (WARN_ON_ONCE(iomap.offset + iomap.length < pos + PAGE_SIZE)) {
vmf_ret = dax_fault_return(-EIO); /* fs corruption? */
goto finish_iomap;
@@ -1234,6 +1239,8 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf,
*/
ops->iomap_end(inode, pos, PAGE_SIZE, copied, flags, &iomap);
}
+out:
+ trace_dax_pte_fault_done(inode, vmf, vmf_ret);
return vmf_ret;
}
@@ -150,6 +150,47 @@ DEFINE_EVENT(dax_pmd_insert_mapping_class, name, \
DEFINE_PMD_INSERT_MAPPING_EVENT(dax_pmd_insert_mapping);
DEFINE_PMD_INSERT_MAPPING_EVENT(dax_pmd_insert_mapping_fallback);
+DECLARE_EVENT_CLASS(dax_pte_fault_class,
+ TP_PROTO(struct inode *inode, struct vm_fault *vmf, int result),
+ TP_ARGS(inode, vmf, result),
+ TP_STRUCT__entry(
+ __field(unsigned long, ino)
+ __field(unsigned long, vm_flags)
+ __field(unsigned long, address)
+ __field(pgoff_t, pgoff)
+ __field(dev_t, dev)
+ __field(unsigned int, flags)
+ __field(int, result)
+ ),
+ TP_fast_assign(
+ __entry->dev = inode->i_sb->s_dev;
+ __entry->ino = inode->i_ino;
+ __entry->vm_flags = vmf->vma->vm_flags;
+ __entry->address = vmf->address;
+ __entry->flags = vmf->flags;
+ __entry->pgoff = vmf->pgoff;
+ __entry->result = result;
+ ),
+ TP_printk("dev %d:%d ino %#lx %s %s address %#lx pgoff %#lx %s",
+ MAJOR(__entry->dev),
+ MINOR(__entry->dev),
+ __entry->ino,
+ __entry->vm_flags & VM_SHARED ? "shared" : "private",
+ __print_flags(__entry->flags, "|", FAULT_FLAG_TRACE),
+ __entry->address,
+ __entry->pgoff,
+ __print_flags(__entry->result, "|", VM_FAULT_RESULT_TRACE)
+ )
+)
+
+#define DEFINE_PTE_FAULT_EVENT(name) \
+DEFINE_EVENT(dax_pte_fault_class, name, \
+ TP_PROTO(struct inode *inode, struct vm_fault *vmf, int result), \
+ TP_ARGS(inode, vmf, result))
+
+DEFINE_PTE_FAULT_EVENT(dax_pte_fault);
+DEFINE_PTE_FAULT_EVENT(dax_pte_fault_done);
+
#endif /* _TRACE_FS_DAX_H */
/* This part must be outside protection */
Add tracepoints to dax_iomap_pte_fault(), following the same logging conventions as the rest of DAX. Here is an example fault that initially tries to be serviced by the PMD fault handler but which falls back to PTEs because the VMA isn't large enough to hold a PMD: small-1086 [005] .... 71.140014: xfs_filemap_huge_fault: dev 259:0 ino 0x1003 small-1086 [005] .... 71.140027: dax_pmd_fault: dev 259:0 ino 0x1003 shared WRITE|ALLOW_RETRY|KILLABLE|USER address 0x10420000 vm_start 0x10200000 vm_end 0x10500000 pgoff 0x220 max_pgoff 0x1400 small-1086 [005] .... 71.140028: dax_pmd_fault_done: dev 259:0 ino 0x1003 shared WRITE|ALLOW_RETRY|KILLABLE|USER address 0x10420000 vm_start 0x10200000 vm_end 0x10500000 pgoff 0x220 max_pgoff 0x1400 FALLBACK small-1086 [005] .... 71.140035: dax_pte_fault: dev 259:0 ino 0x1003 shared WRITE|ALLOW_RETRY|KILLABLE|USER address 0x10420000 pgoff 0x220 small-1086 [005] .... 71.140396: dax_pte_fault_done: dev 259:0 ino 0x1003 shared WRITE|ALLOW_RETRY|KILLABLE|USER address 0x10420000 pgoff 0x220 MAJOR|NOPAGE Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> --- fs/dax.c | 15 +++++++++++---- include/trace/events/fs_dax.h | 41 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+), 4 deletions(-)