A lot of CPU time is wasted on allocating, populating, and copying
debug names back and forth with userspace when they're not actually
needed. We can't just remove the name buffers from the various sync data
structures though because we must preserve ABI compatibility with
userspace, but instead we can just pretend the name fields of the
user-shared structs aren't there. This massively reduces the sizes of
memory allocated for these data structures and the amount of data passed
between userspace, as well as eliminates a kzalloc() entirely from
sync_file_ioctl_fence_info(), thus improving graphics performance.
Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
[ Upstream commit b794918961516f667b0c745aebdfebbb8a98df39 ]
Since commit a6aa8fca4d79 ("dma-buf/sw-sync: Reduce irqsave/irqrestore from
known context") by error replaced spin_unlock_irqrestore() with
spin_unlock_irq() for both sync_debugfs_show() and sync_print_obj() despite
sync_print_obj() is called from sync_debugfs_show(), lockdep complains
inconsistent lock state warning.
Use plain spin_{lock,unlock}() for sync_print_obj(), for
sync_debugfs_show() is already using spin_{lock,unlock}_irq().
Reported-by: syzbot <syzbot+a225ee3df7e7f9372dbe@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=a225ee3df7e7f9372dbe
Fixes: a6aa8fca4d79 ("dma-buf/sw-sync: Reduce irqsave/irqrestore from known context")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/c2e46020-aaa6-4e06-bf73-f05823f913f0@I-love.SAKURA.ne.jp
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
