| Message ID | 1556234531-108228-1-git-send-email-yang.shi@linux.alibaba.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm: filemap: correct the comment about VM_FAULT_RETRY | expand |
Ping. Josef, any comment on this one? Thanks, Yang On 4/25/19 4:22 PM, Yang Shi wrote: > The commit 6b4c9f446981 ("filemap: drop the mmap_sem for all blocking > operations") changed when mmap_sem is dropped during filemap page fault > and when returning VM_FAULT_RETRY. > > Correct the comment to reflect the change. > > Cc: Josef Bacik <josef@toxicpanda.com> > Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> > --- > mm/filemap.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/mm/filemap.c b/mm/filemap.c > index d78f577..f0d6250 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -2545,10 +2545,8 @@ static struct file *do_async_mmap_readahead(struct vm_fault *vmf, > * > * vma->vm_mm->mmap_sem must be held on entry. > * > - * If our return value has VM_FAULT_RETRY set, it's because > - * lock_page_or_retry() returned 0. > - * The mmap_sem has usually been released in this case. > - * See __lock_page_or_retry() for the exception. > + * If our return value has VM_FAULT_RETRY set, it's because the mmap_sem > + * may be dropped before doing I/O or by lock_page_maybe_drop_mmap(). > * > * If our return value does not have VM_FAULT_RETRY set, the mmap_sem > * has not been released.
Hi Josef, Any comment on this patch? I switched to my personal email since the mail may get bounced back with my work email sometime. On Wed, May 8, 2019 at 9:55 AM Yang Shi <yang.shi@linux.alibaba.com> wrote: > > Ping. > > > Josef, any comment on this one? > > > Thanks, > > Yang > > > > On 4/25/19 4:22 PM, Yang Shi wrote: > > The commit 6b4c9f446981 ("filemap: drop the mmap_sem for all blocking > > operations") changed when mmap_sem is dropped during filemap page fault > > and when returning VM_FAULT_RETRY. > > > > Correct the comment to reflect the change. > > > > Cc: Josef Bacik <josef@toxicpanda.com> > > Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> > > --- > > mm/filemap.c | 6 ++---- > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/mm/filemap.c b/mm/filemap.c > > index d78f577..f0d6250 100644 > > --- a/mm/filemap.c > > +++ b/mm/filemap.c > > @@ -2545,10 +2545,8 @@ static struct file *do_async_mmap_readahead(struct vm_fault *vmf, > > * > > * vma->vm_mm->mmap_sem must be held on entry. > > * > > - * If our return value has VM_FAULT_RETRY set, it's because > > - * lock_page_or_retry() returned 0. > > - * The mmap_sem has usually been released in this case. > > - * See __lock_page_or_retry() for the exception. > > + * If our return value has VM_FAULT_RETRY set, it's because the mmap_sem > > + * may be dropped before doing I/O or by lock_page_maybe_drop_mmap(). > > * > > * If our return value does not have VM_FAULT_RETRY set, the mmap_sem > > * has not been released. >
On Thu, Apr 25, 2019 at 4:22 PM Yang Shi <yang.shi@linux.alibaba.com> wrote: > > The commit 6b4c9f446981 ("filemap: drop the mmap_sem for all blocking > operations") changed when mmap_sem is dropped during filemap page fault > and when returning VM_FAULT_RETRY. > > Correct the comment to reflect the change. > > Cc: Josef Bacik <josef@toxicpanda.com> > Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> Looks good to me! Acked-by: Song Liu <songliubraving@fb.com> > --- > mm/filemap.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/mm/filemap.c b/mm/filemap.c > index d78f577..f0d6250 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -2545,10 +2545,8 @@ static struct file *do_async_mmap_readahead(struct vm_fault *vmf, > * > * vma->vm_mm->mmap_sem must be held on entry. > * > - * If our return value has VM_FAULT_RETRY set, it's because > - * lock_page_or_retry() returned 0. > - * The mmap_sem has usually been released in this case. > - * See __lock_page_or_retry() for the exception. > + * If our return value has VM_FAULT_RETRY set, it's because the mmap_sem > + * may be dropped before doing I/O or by lock_page_maybe_drop_mmap(). > * > * If our return value does not have VM_FAULT_RETRY set, the mmap_sem > * has not been released. > -- > 1.8.3.1 >
On Fri, Apr 26, 2019 at 07:22:11AM +0800, Yang Shi wrote: > The commit 6b4c9f446981 ("filemap: drop the mmap_sem for all blocking > operations") changed when mmap_sem is dropped during filemap page fault > and when returning VM_FAULT_RETRY. > > Correct the comment to reflect the change. > > Cc: Josef Bacik <josef@toxicpanda.com> > Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> > --- Reviewed-by: Josef Bacik <josef@toxicpanda.com> Thanks, Josef
diff --git a/mm/filemap.c b/mm/filemap.c index d78f577..f0d6250 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2545,10 +2545,8 @@ static struct file *do_async_mmap_readahead(struct vm_fault *vmf, * * vma->vm_mm->mmap_sem must be held on entry. * - * If our return value has VM_FAULT_RETRY set, it's because - * lock_page_or_retry() returned 0. - * The mmap_sem has usually been released in this case. - * See __lock_page_or_retry() for the exception. + * If our return value has VM_FAULT_RETRY set, it's because the mmap_sem + * may be dropped before doing I/O or by lock_page_maybe_drop_mmap(). * * If our return value does not have VM_FAULT_RETRY set, the mmap_sem * has not been released.
The commit 6b4c9f446981 ("filemap: drop the mmap_sem for all blocking operations") changed when mmap_sem is dropped during filemap page fault and when returning VM_FAULT_RETRY. Correct the comment to reflect the change. Cc: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> --- mm/filemap.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)