| Message ID | 20221101022840.1351163-3-tgsp002@gmail.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | Fixes to the hibernate_preallocate_memory() | expand |
On Tue, Nov 1, 2022 at 3:28 AM TGSP <tgsp002@gmail.com> wrote: > > From: xiongxin <xiongxin@kylinos.cn> > > Added a check on the return value of preallocate_image_highmem(). If > memory preallocate is insufficient, S4 cannot be done; > > I am playing 4K video on a machine with AMD or other graphics card and > only 8GiB memory, and the kernel is not configured with CONFIG_HIGHMEM. > When doing the S4 test, the analysis found that when the pages get from > minimum_image_size() is large enough, The preallocate_image_memory() and > preallocate_image_highmem() calls failed to obtain enough memory. Add > the judgment that memory preallocate is insufficient; > > "pages -= free_unnecessary_pages()" below will let pages to drop a lot, > so I wonder if it makes sense to add a judgment here. > > Cc: stable@vger.kernel.org > Signed-off-by: xiongxin <xiongxin@kylinos.cn> > Signed-off-by: huanglei <huanglei@kylinos.cn> > --- > kernel/power/snapshot.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c > index c20ca5fb9adc..670abf89cf31 100644 > --- a/kernel/power/snapshot.c > +++ b/kernel/power/snapshot.c > @@ -1738,6 +1738,7 @@ int hibernate_preallocate_memory(void) > struct zone *zone; > unsigned long saveable, size, max_size, count, highmem, pages = 0; > unsigned long alloc, save_highmem, pages_highmem, avail_normal; > + unsigned long size_highmem; Please define this in the block where it will be used. > ktime_t start, stop; > int error; > > @@ -1863,7 +1864,13 @@ int hibernate_preallocate_memory(void) > pages_highmem += size; The line above can be dropped. > alloc -= size; > size = preallocate_image_memory(alloc, avail_normal); > - pages_highmem += preallocate_image_highmem(alloc - size); > + size_highmem += preallocate_image_highmem(alloc - size); Did you mean "="? Assuming you did, this could be size_highmem = size + preallocate_image_highmem(alloc - size); if (size_highmem < alloc) { > + if (size_highmem < (alloc - size)) { The inner parens were not necessary. > + pr_err("Image allocation is %lu pages short, exit\n", > + alloc - size - pages_highmem); > + goto err_out; > + } > + pages_highmem += size_highmem; > pages += pages_highmem + size; > } > > -- But overall it would be better to avoid bailing out.
On Thu, Nov 3, 2022 at 5:47 PM Rafael J. Wysocki <rafael@kernel.org> wrote: > > On Tue, Nov 1, 2022 at 3:28 AM TGSP <tgsp002@gmail.com> wrote: > > > > From: xiongxin <xiongxin@kylinos.cn> > > > > Added a check on the return value of preallocate_image_highmem(). If > > memory preallocate is insufficient, S4 cannot be done; > > > > I am playing 4K video on a machine with AMD or other graphics card and > > only 8GiB memory, and the kernel is not configured with CONFIG_HIGHMEM. > > When doing the S4 test, the analysis found that when the pages get from > > minimum_image_size() is large enough, The preallocate_image_memory() and > > preallocate_image_highmem() calls failed to obtain enough memory. Add > > the judgment that memory preallocate is insufficient; > > > > "pages -= free_unnecessary_pages()" below will let pages to drop a lot, > > so I wonder if it makes sense to add a judgment here. > > > > Cc: stable@vger.kernel.org > > Signed-off-by: xiongxin <xiongxin@kylinos.cn> > > Signed-off-by: huanglei <huanglei@kylinos.cn> > > --- > > kernel/power/snapshot.c | 9 ++++++++- > > 1 file changed, 8 insertions(+), 1 deletion(-) > > > > diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c > > index c20ca5fb9adc..670abf89cf31 100644 > > --- a/kernel/power/snapshot.c > > +++ b/kernel/power/snapshot.c > > @@ -1738,6 +1738,7 @@ int hibernate_preallocate_memory(void) > > struct zone *zone; > > unsigned long saveable, size, max_size, count, highmem, pages = 0; > > unsigned long alloc, save_highmem, pages_highmem, avail_normal; > > + unsigned long size_highmem; > > Please define this in the block where it will be used. > > > ktime_t start, stop; > > int error; > > > > @@ -1863,7 +1864,13 @@ int hibernate_preallocate_memory(void) > > pages_highmem += size; > > The line above can be dropped. Not really, it needs to be replaced with size_highmem = size ; > > alloc -= size; > > size = preallocate_image_memory(alloc, avail_normal); > > - pages_highmem += preallocate_image_highmem(alloc - size); > > + size_highmem += preallocate_image_highmem(alloc - size); > > Did you mean "="? > > Assuming you did, this could be > > size_highmem = size + preallocate_image_highmem(alloc - size); And here size_highmem += preallocate_image_highmem(alloc - size); which is what you had in the original patch. > if (size_highmem < alloc) { > > > + if (size_highmem < (alloc - size)) { > > The inner parens were not necessary. > > > + pr_err("Image allocation is %lu pages short, exit\n", > > + alloc - size - pages_highmem); > > + goto err_out; > > + } > > + pages_highmem += size_highmem; > > pages += pages_highmem + size; > > } > > > > -- > > But overall it would be better to avoid bailing out.
On Tue, Nov 1, 2022 at 3:28 AM TGSP <tgsp002@gmail.com> wrote: > > From: xiongxin <xiongxin@kylinos.cn> > > Added a check on the return value of preallocate_image_highmem(). If > memory preallocate is insufficient, S4 cannot be done; > > I am playing 4K video on a machine with AMD or other graphics card and > only 8GiB memory, and the kernel is not configured with CONFIG_HIGHMEM. > When doing the S4 test, the analysis found that when the pages get from > minimum_image_size() is large enough, The preallocate_image_memory() and > preallocate_image_highmem() calls failed to obtain enough memory. Add > the judgment that memory preallocate is insufficient; So I'm not sure what the problem is. Can you please explain it in more detail? The if (pages < alloc) appears to be false in your case, so there should be enough free pages to create an image. Maybe reserved_size is too low?
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index c20ca5fb9adc..670abf89cf31 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1738,6 +1738,7 @@ int hibernate_preallocate_memory(void) struct zone *zone; unsigned long saveable, size, max_size, count, highmem, pages = 0; unsigned long alloc, save_highmem, pages_highmem, avail_normal; + unsigned long size_highmem; ktime_t start, stop; int error; @@ -1863,7 +1864,13 @@ int hibernate_preallocate_memory(void) pages_highmem += size; alloc -= size; size = preallocate_image_memory(alloc, avail_normal); - pages_highmem += preallocate_image_highmem(alloc - size); + size_highmem += preallocate_image_highmem(alloc - size); + if (size_highmem < (alloc - size)) { + pr_err("Image allocation is %lu pages short, exit\n", + alloc - size - pages_highmem); + goto err_out; + } + pages_highmem += size_highmem; pages += pages_highmem + size; }