On Wed, Feb 12, 2025 at 12:56:46PM -0500, Peter Xu wrote: > On Wed, Feb 12, 2025 at 05:48:46PM +0000, Daniel P. Berrangé wrote: > > On Wed, Feb 12, 2025 at 12:38:23PM -0500, Peter Xu wrote: > > > From: Daniil Tatianin <d-tatia...@yandex-team.ru> > > > > > > This will be used in the following commits to make it possible to only > > > lock memory on fault instead of right away. > > > > > > Signed-off-by: Daniil Tatianin <d-tatia...@yandex-team.ru> > > > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru> > > > Link: > > > https://lore.kernel.org/r/20250212143920.1269754-2-d-tatia...@yandex-team.ru > > > [peterx: fail os_mlock(on_fault=1) when not supported] > > > [peterx: use G_GNUC_UNUSED instead of "(void)on_fault", per Dan] > > > Signed-off-by: Peter Xu <pet...@redhat.com> > > > --- > > > meson.build | 6 ++++++ > > > include/system/os-posix.h | 2 +- > > > include/system/os-win32.h | 2 +- > > > migration/postcopy-ram.c | 2 +- > > > os-posix.c | 15 +++++++++++++-- > > > system/vl.c | 2 +- > > > 6 files changed, 23 insertions(+), 6 deletions(-) > > > > > > diff --git a/meson.build b/meson.build > > > index 18cf9e2913..59953cbe6b 100644 > > > --- a/meson.build > > > +++ b/meson.build > > > @@ -2885,6 +2885,12 @@ config_host_data.set('HAVE_MLOCKALL', > > > cc.links(gnu_source_prefix + ''' > > > return mlockall(MCL_FUTURE); > > > }''')) > > > > > > +config_host_data.set('HAVE_MLOCK_ONFAULT', cc.links(gnu_source_prefix + > > > ''' > > > + #include <sys/mman.h> > > > + int main(void) { > > > + return mlockall(MCL_FUTURE | MCL_ONFAULT); > > > + }''')) > > > + > > > have_l2tpv3 = false > > > if get_option('l2tpv3').allowed() and have_system > > > have_l2tpv3 = cc.has_type('struct mmsghdr', > > > diff --git a/include/system/os-posix.h b/include/system/os-posix.h > > > index b881ac6c6f..ce5b3bccf8 100644 > > > --- a/include/system/os-posix.h > > > +++ b/include/system/os-posix.h > > > @@ -53,7 +53,7 @@ bool os_set_runas(const char *user_id); > > > void os_set_chroot(const char *path); > > > void os_setup_limits(void); > > > void os_setup_post(void); > > > -int os_mlock(void); > > > +int os_mlock(bool on_fault); > > > > > > /** > > > * qemu_alloc_stack: > > > diff --git a/include/system/os-win32.h b/include/system/os-win32.h > > > index b82a5d3ad9..bc623061d8 100644 > > > --- a/include/system/os-win32.h > > > +++ b/include/system/os-win32.h > > > @@ -123,7 +123,7 @@ static inline bool is_daemonized(void) > > > return false; > > > } > > > > > > -static inline int os_mlock(void) > > > +static inline int os_mlock(bool on_fault G_GNUC_UNUSED) > > > > So did this actually generate a warning ? We don' even need > > G_GNUC_UNUSED unless we're actually seeing warnings about this. > > I didn't try to hit a warning without it, as we can use different compilers > and I thought the results could be different, even if I try it and it > didn't raise a warning?
We strictly only permit use of clang & gcc. > I do see though that we have plenty of such uses in the current tree, > though. Does it mean it's a broader question to ask, rather than this > patch only? > > Thanks, > > -- > Peter Xu > With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
