On 2/27/26 15:06, Yuvraj Sakshith wrote: > Today, page reporting sets page_reporting_order in two ways: > > (1) page_reporting.page_reporting_order cmdline parameter > (2) Driver can pass order while registering itself. > > In both cases, order zero is ignored by free page reporting > because it is used to set page_reporting_order to a default > value, like MAX_PAGE_ORDER. > > In some cases we might want page_reporting_order to be zero. > > For instance, when virtio-balloon runs inside a guest with > tiny memory (say, 16MB), it might not be able to find a order 1 page > (or in the worst case order MAX_PAGE_ORDER page) after some uptime. > Page reporting should be able to return order zero pages back for > optimal memory relinquishment. > > This patch changes the default fallback value from '0' to '-1' in > all possible clients of free page reporting (hv_balloon and > virtio-balloon) together with allowing '0' as a valid order in > page_reporting_register(). > > Changes in v1: > - Introduce PAGE_REPORTING_DEFAULT_ORDER macro (initially set to 0). > - Make use of new macro in drivers (hv_balloon and virtio-balloon) > working with page reporting. > - Change PAGE_REPORTING_DEFAULT_ORDER to -1 as zero is a valid > page order that can be requested. > > Yuvraj Sakshith (3): > mm/page_reporting: Allow zero page_reporting_order > hv_balloon: Change default page reporting order > virtio_balloon: Set pr_dev.order to new default
These look like old stats :) -- Cheers, David
