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| author | Jiri Slaby <jslaby@suse.cz> | 2021-05-05 11:19:06 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-05-13 16:57:16 +0200 |
| commit | 64d608db38ffc0c7a25455387096e0aad9410397 (patch) | |
| tree | 356a8ff491e272f0d497c9da4401c7f0827c425d /drivers/tty/vt/vt.c | |
| parent | 6e94dbc7a4e49a028b81302d755bba1a518f973b (diff) | |
| download | linux-64d608db38ffc0c7a25455387096e0aad9410397.tar.gz linux-64d608db38ffc0c7a25455387096e0aad9410397.tar.bz2 linux-64d608db38ffc0c7a25455387096e0aad9410397.zip | |
tty: cumulate and document tty_struct::ctrl* members
Group the ctrl members under a single struct called ctrl. The new struct
contains 'pgrp', 'session', 'pktstatus', and 'packet'. 'pktstatus' and
'packet' used to be bits in a bitfield. The struct also contains the
lock protecting them to share the same cache line.
Note that commit c545b66c6922b (tty: Serialize tcflow() with other tty
flow control changes) added a padding to the original bitfield. It was
for the bitfield to occupy a whole 64b word to avoid interferring stores
on Alpha (cannot we evaporate this arch with weird implications to C
code yet?). But it doesn't work as expected as the padding
(tty_struct::ctrl_unused) is aligned to a 8B boundary too and occupies
some bytes from the next word.
So make it reliable by:
1) setting __aligned of the struct -- that aligns the start, and
2) making 'unsigned long unused[0]' as the last member of the struct --
pads the end.
Add a kerneldoc comment for this grouped members.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Link: https://lore.kernel.org/r/20210505091928.22010-14-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/vt/vt.c')
| -rw-r--r-- | drivers/tty/vt/vt.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 38c677fb6505..706f066eb711 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -1189,7 +1189,7 @@ static inline int resize_screen(struct vc_data *vc, int width, int height, * information and perform any necessary signal handling. * * Caller must hold the console semaphore. Takes the termios rwsem and - * ctrl_lock of the tty IFF a tty is passed. + * ctrl.lock of the tty IFF a tty is passed. */ static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc, @@ -1355,7 +1355,7 @@ int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows) * the actual work. * * Takes the console sem and the called methods then take the tty - * termios_rwsem and the tty ctrl_lock in that order. + * termios_rwsem and the tty ctrl.lock in that order. */ static int vt_resize(struct tty_struct *tty, struct winsize *ws) { |