| Message ID | 20190524085354.27411-5-daniel.vetter@ffwll.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fbcon notifier begone! | expand |
On Fri, May 24, 2019 at 10:53:25AM +0200, Daniel Vetter wrote: > I honestly have no idea what the subtle differences between > con_is_visible, con_is_fg (internal to vt.c) and con_is_bound are. But > it looks like both vc->vc_display_fg and con_driver_map are protected > by the console_lock, so probably better if we hold that when checking > this. > > To do that I had to deinline the con_is_visible function. > > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Cc: Nicolas Pitre <nicolas.pitre@linaro.org> > Cc: Martin Hostettler <textshell@uchuujin.de> > Cc: Adam Borowski <kilobyte@angband.pl> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > Cc: Mikulas Patocka <mpatocka@redhat.com> Hi Greg, Do you want to merge this through your console tree or ack for merging through drm/fbdev? It's part of a bigger series, and I'd like to have more testing with this in our trees, but also ok to merge stand-alone if you prefer that. It's just locking checks and some docs. Same for the preceeding patch in this series here. Thanks, Daniel > --- > drivers/tty/vt/vt.c | 16 ++++++++++++++++ > include/linux/console_struct.h | 5 +---- > 2 files changed, 17 insertions(+), 4 deletions(-) > > diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c > index bc9813b14c58..a8988a085138 100644 > --- a/drivers/tty/vt/vt.c > +++ b/drivers/tty/vt/vt.c > @@ -3815,6 +3815,8 @@ int con_is_bound(const struct consw *csw) > { > int i, bound = 0; > > + WARN_CONSOLE_UNLOCKED(); > + > for (i = 0; i < MAX_NR_CONSOLES; i++) { > if (con_driver_map[i] == csw) { > bound = 1; > @@ -3826,6 +3828,20 @@ int con_is_bound(const struct consw *csw) > } > EXPORT_SYMBOL(con_is_bound); > > +/** > + * con_is_visible - checks whether the current console is visible > + * @vc: virtual console > + * > + * RETURNS: zero if not visible, nonzero if visible > + */ > +bool con_is_visible(const struct vc_data *vc) > +{ > + WARN_CONSOLE_UNLOCKED(); > + > + return *vc->vc_display_fg == vc; > +} > +EXPORT_SYMBOL(con_is_visible); > + > /** > * con_debug_enter - prepare the console for the kernel debugger > * @sw: console driver > diff --git a/include/linux/console_struct.h b/include/linux/console_struct.h > index ed798e114663..24d4c16e3ae0 100644 > --- a/include/linux/console_struct.h > +++ b/include/linux/console_struct.h > @@ -168,9 +168,6 @@ extern void vc_SAK(struct work_struct *work); > > #define CUR_DEFAULT CUR_UNDERLINE > > -static inline bool con_is_visible(const struct vc_data *vc) > -{ > - return *vc->vc_display_fg == vc; > -} > +bool con_is_visible(const struct vc_data *vc); > > #endif /* _LINUX_CONSOLE_STRUCT_H */ > -- > 2.20.1 >
On Mon, May 27, 2019 at 09:08:58AM +0200, Daniel Vetter wrote: > On Fri, May 24, 2019 at 10:53:25AM +0200, Daniel Vetter wrote: > > I honestly have no idea what the subtle differences between > > con_is_visible, con_is_fg (internal to vt.c) and con_is_bound are. But > > it looks like both vc->vc_display_fg and con_driver_map are protected > > by the console_lock, so probably better if we hold that when checking > > this. > > > > To do that I had to deinline the con_is_visible function. > > > > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> > > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > Cc: Nicolas Pitre <nicolas.pitre@linaro.org> > > Cc: Martin Hostettler <textshell@uchuujin.de> > > Cc: Adam Borowski <kilobyte@angband.pl> > > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > > Cc: Mikulas Patocka <mpatocka@redhat.com> > > Hi Greg, > > Do you want to merge this through your console tree or ack for merging > through drm/fbdev? It's part of a bigger series, and I'd like to have more > testing with this in our trees, but also ok to merge stand-alone if you > prefer that. It's just locking checks and some docs. > > Same for the preceeding patch in this series here. For all of these, please take them through your tree(s): Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index bc9813b14c58..a8988a085138 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -3815,6 +3815,8 @@ int con_is_bound(const struct consw *csw) { int i, bound = 0; + WARN_CONSOLE_UNLOCKED(); + for (i = 0; i < MAX_NR_CONSOLES; i++) { if (con_driver_map[i] == csw) { bound = 1; @@ -3826,6 +3828,20 @@ int con_is_bound(const struct consw *csw) } EXPORT_SYMBOL(con_is_bound); +/** + * con_is_visible - checks whether the current console is visible + * @vc: virtual console + * + * RETURNS: zero if not visible, nonzero if visible + */ +bool con_is_visible(const struct vc_data *vc) +{ + WARN_CONSOLE_UNLOCKED(); + + return *vc->vc_display_fg == vc; +} +EXPORT_SYMBOL(con_is_visible); + /** * con_debug_enter - prepare the console for the kernel debugger * @sw: console driver diff --git a/include/linux/console_struct.h b/include/linux/console_struct.h index ed798e114663..24d4c16e3ae0 100644 --- a/include/linux/console_struct.h +++ b/include/linux/console_struct.h @@ -168,9 +168,6 @@ extern void vc_SAK(struct work_struct *work); #define CUR_DEFAULT CUR_UNDERLINE -static inline bool con_is_visible(const struct vc_data *vc) -{ - return *vc->vc_display_fg == vc; -} +bool con_is_visible(const struct vc_data *vc); #endif /* _LINUX_CONSOLE_STRUCT_H */
I honestly have no idea what the subtle differences between con_is_visible, con_is_fg (internal to vt.c) and con_is_bound are. But it looks like both vc->vc_display_fg and con_driver_map are protected by the console_lock, so probably better if we hold that when checking this. To do that I had to deinline the con_is_visible function. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Martin Hostettler <textshell@uchuujin.de> Cc: Adam Borowski <kilobyte@angband.pl> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Mikulas Patocka <mpatocka@redhat.com> --- drivers/tty/vt/vt.c | 16 ++++++++++++++++ include/linux/console_struct.h | 5 +---- 2 files changed, 17 insertions(+), 4 deletions(-)