| Message ID | 2a9a998e-f2d0-3c07-e85e-7fdda18b506e@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | libxl/PCI: reserved device memory adjustments | expand |
On Tue, Feb 18, 2020 at 04:47:49PM +0100, Jan Beulich wrote: > As the code comment says, this will allow use of a 2Mb super page > mapping at the end of "low" memory. > > Signed-off-by: Jan Beulich <jbeulich@suse.com> > > --- a/tools/libxl/libxl_dm.c > +++ b/tools/libxl/libxl_dm.c > @@ -563,6 +563,13 @@ int libxl__domain_device_construct_rdm(l > /* Just check if RDM > our memory boundary. */ > if (rdm_start > rdm_mem_boundary) { > /* > + * For HAP guests round down to a 2Mb boundary to allow use > + * of large page mappings. > + */ > + if (libxl_defbool_val(d_config->c_info.hap) > + && rdm_start > 0x200000) Please use MB(2) here. With this fixed: Acked-by: Wei Liu <wl@xen.org>
On 20.02.2020 12:43, Wei Liu wrote: > On Tue, Feb 18, 2020 at 04:47:49PM +0100, Jan Beulich wrote: >> As the code comment says, this will allow use of a 2Mb super page >> mapping at the end of "low" memory. >> >> Signed-off-by: Jan Beulich <jbeulich@suse.com> >> >> --- a/tools/libxl/libxl_dm.c >> +++ b/tools/libxl/libxl_dm.c >> @@ -563,6 +563,13 @@ int libxl__domain_device_construct_rdm(l >> /* Just check if RDM > our memory boundary. */ >> if (rdm_start > rdm_mem_boundary) { >> /* >> + * For HAP guests round down to a 2Mb boundary to allow use >> + * of large page mappings. >> + */ >> + if (libxl_defbool_val(d_config->c_info.hap) >> + && rdm_start > 0x200000) > > Please use MB(2) here. Will do, but then what about the ~0x1fffff on the next line? Should this become ~(MB(2) - 1)? > With this fixed: > > Acked-by: Wei Liu <wl@xen.org> Thanks. Jan
On Thu, Feb 20, 2020 at 12:45:54PM +0100, Jan Beulich wrote: > On 20.02.2020 12:43, Wei Liu wrote: > > On Tue, Feb 18, 2020 at 04:47:49PM +0100, Jan Beulich wrote: > >> As the code comment says, this will allow use of a 2Mb super page > >> mapping at the end of "low" memory. > >> > >> Signed-off-by: Jan Beulich <jbeulich@suse.com> > >> > >> --- a/tools/libxl/libxl_dm.c > >> +++ b/tools/libxl/libxl_dm.c > >> @@ -563,6 +563,13 @@ int libxl__domain_device_construct_rdm(l > >> /* Just check if RDM > our memory boundary. */ > >> if (rdm_start > rdm_mem_boundary) { > >> /* > >> + * For HAP guests round down to a 2Mb boundary to allow use > >> + * of large page mappings. > >> + */ > >> + if (libxl_defbool_val(d_config->c_info.hap) > >> + && rdm_start > 0x200000) > > > > Please use MB(2) here. > > Will do, but then what about the ~0x1fffff on the next line? Should > this become ~(MB(2) - 1)? Yes that would be good too. Wei.
--- a/tools/libxl/libxl_dm.c +++ b/tools/libxl/libxl_dm.c @@ -563,6 +563,13 @@ int libxl__domain_device_construct_rdm(l /* Just check if RDM > our memory boundary. */ if (rdm_start > rdm_mem_boundary) { /* + * For HAP guests round down to a 2Mb boundary to allow use + * of large page mappings. + */ + if (libxl_defbool_val(d_config->c_info.hap) + && rdm_start > 0x200000) + rdm_start &= ~0x1fffff; + /* * We will move downwards lowmem_end so we have to expand * highmem_end. */
As the code comment says, this will allow use of a 2Mb super page mapping at the end of "low" memory. Signed-off-by: Jan Beulich <jbeulich@suse.com>