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Message-ID: <CAKMK7uEfyaex+kWyphReA9uaX9p21hDd_WquskocarvWtq1MHA@mail.gmail.com>
Date: Mon, 20 May 2019 19:29:52 +0200
From: Daniel Vetter <daniel.vetter@...ll.ch>
To: Sam Ravnborg <sam@...nborg.org>
Cc: DRI Development <dri-devel@...ts.freedesktop.org>,
Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>,
Intel Graphics Development <intel-gfx@...ts.freedesktop.org>,
LKML <linux-kernel@...r.kernel.org>,
Michał Mirosław <mirq-linux@...e.qmqm.pl>,
Yisheng Xie <ysxie@...mail.com>,
Hans de Goede <hdegoede@...hat.com>,
Mikulas Patocka <mpatocka@...hat.com>,
Daniel Vetter <daniel.vetter@...el.com>,
Peter Rosin <peda@...ntia.se>
Subject: Re: [PATCH 27/33] fbdev: remove FBINFO_MISC_USEREVENT around fb_blank
On Mon, May 20, 2019 at 7:20 PM Sam Ravnborg <sam@...nborg.org> wrote:
>
> Hi Daniel.
>
> > With the recursion broken in the previous patch we can drop the
> > FBINFO_MISC_USEREVENT flag around calls to fb_blank - recursion
> > prevention was it's only job.
> >
> When grepping for FBINFO_MISC_USEREVENT I get a few hits not addressed
> in the patch below:
>
> drivers/video/fbdev/core/fbcon.c: if (!(info->flags & FBINFO_MISC_USEREVENT))
> drivers/video/fbdev/core/fbmem.c: if (!ret && (flags & FBINFO_MISC_USEREVENT)) {
> drivers/video/fbdev/core/fbmem.c: info->flags &= ~FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/core/fbmem.c: info->flags |= FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/core/fbmem.c: info->flags &= ~FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/core/fbmem.c: info->flags |= FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/core/fbmem.c: info->flags &= ~FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/core/fbsysfs.c: fb_info->flags |= FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/core/fbsysfs.c: fb_info->flags &= ~FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/core/fbsysfs.c: fb_info->flags |= FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/core/fbsysfs.c: fb_info->flags &= ~FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/ps3fb.c: info->flags |= FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/ps3fb.c: info->flags &= ~FBINFO_MISC_USEREVENT;
> drivers/video/fbdev/sh_mobile_lcdcfb.c: * FBINFO_MISC_USEREVENT flag is set. Since we do not want to fake a
> include/linux/fb.h:#define FBINFO_MISC_USEREVENT 0x10000 /* event request
>
> The use in ps3fb looks like a candidate for removal and this file is not
> touch in this patch series, so I guess I did not miss it.
>
> As I did not apply the full series maybe some of the other users was
> already taken care of.
It's also used to break recursion around fb_set_par and fb_set_pan.
Untangling that one would be possible, but also requires untangling
some locking, so a lot more work. If you chase all the call paths then
you'll noticed that the users still left have no overlap with the ones
I'm removing here.
-Daniel
>
>
> Sam
>
> > Signed-off-by: Daniel Vetter <daniel.vetter@...el.com>
> > Cc: Daniel Vetter <daniel.vetter@...ll.ch>
> > Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
> > Cc: Hans de Goede <hdegoede@...hat.com>
> > Cc: Yisheng Xie <ysxie@...mail.com>
> > Cc: "Michał Mirosław" <mirq-linux@...e.qmqm.pl>
> > Cc: Peter Rosin <peda@...ntia.se>
> > Cc: Mikulas Patocka <mpatocka@...hat.com>
> > Cc: Rob Clark <robdclark@...il.com>
> > ---
> > drivers/video/fbdev/core/fbcon.c | 5 ++---
> > drivers/video/fbdev/core/fbmem.c | 3 ---
> > drivers/video/fbdev/core/fbsysfs.c | 2 --
> > 3 files changed, 2 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
> > index f85d794a3bee..c1a7476e980f 100644
> > --- a/drivers/video/fbdev/core/fbcon.c
> > +++ b/drivers/video/fbdev/core/fbcon.c
> > @@ -2382,9 +2382,8 @@ static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
> > fbcon_cursor(vc, blank ? CM_ERASE : CM_DRAW);
> > ops->cursor_flash = (!blank);
> >
> > - if (!(info->flags & FBINFO_MISC_USEREVENT))
> > - if (fb_blank(info, blank))
> > - fbcon_generic_blank(vc, info, blank);
> > + if (fb_blank(info, blank))
> > + fbcon_generic_blank(vc, info, blank);
> > }
> >
> > if (!blank)
> > diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
> > index 7f95c7e80155..65a075ccac4a 100644
> > --- a/drivers/video/fbdev/core/fbmem.c
> > +++ b/drivers/video/fbdev/core/fbmem.c
> > @@ -1194,10 +1194,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
> > case FBIOBLANK:
> > console_lock();
> > lock_fb_info(info);
> > - info->flags |= FBINFO_MISC_USEREVENT;
> > ret = fb_blank(info, arg);
> > - info->flags &= ~FBINFO_MISC_USEREVENT;
> > -
> > /* might again call into fb_blank */
> > fbcon_fb_blanked(info, arg);
> > unlock_fb_info(info);
> > diff --git a/drivers/video/fbdev/core/fbsysfs.c b/drivers/video/fbdev/core/fbsysfs.c
> > index 252d4f52d2a5..882b471d619e 100644
> > --- a/drivers/video/fbdev/core/fbsysfs.c
> > +++ b/drivers/video/fbdev/core/fbsysfs.c
> > @@ -310,9 +310,7 @@ static ssize_t store_blank(struct device *device,
> >
> > arg = simple_strtoul(buf, &last, 0);
> > console_lock();
> > - fb_info->flags |= FBINFO_MISC_USEREVENT;
> > err = fb_blank(fb_info, arg);
> > - fb_info->flags &= ~FBINFO_MISC_USEREVENT;
> > /* might again call into fb_blank */
> > fbcon_fb_blanked(fb_info, arg);
> > console_unlock();
> > --
> > 2.20.1
> >
> > _______________________________________________
> > dri-devel mailing list
> > dri-devel@...ts.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/dri-devel
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
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