Messages in this thread |  | | Date | Tue, 21 Oct 2014 12:36:22 +0200 | From | Pavel Machek <> | Subject | Re: [PATCH] staging: android: binder: move to the "real" part of the kernel |
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On Fri 2014-10-17 01:12:21, Greg Kroah-Hartman wrote: > On Thu, Oct 16, 2014 at 10:09:04AM -0700, John Stultz wrote: > > On Thu, Oct 16, 2014 at 5:47 AM, Greg Kroah-Hartman > > <gregkh@linuxfoundation.org> wrote: > > > From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > Are the Android guys comfortable with the ABI stability rules they'll > > now face? > > Just because something is in staging, doesn't mean you don't have to > follow the same ABI stability rules as the rest of the kernel. If a > change had happened to this code that broke userspace in the past, I > would have reverted it. So this should not be anything different from > what has been happening inthe past.
Actually, there's big difference.
If Al Viro changes core filesystem in a way that breaks staging/binder, binder is broken, and if it can't be fixed... well it can't be fixed.
If Al Viro changes core filesystem in a way that breaks drivers/binder, Al's change is going to be reverted.
It is really hard to review without API documentation. Normally, API documentation is required for stuff like this.
For example: does it add new files in /proc?
Given that it is stable, can we get rid of binder_debug() and especially BINDER_DEBUG_ENTRY stuff?
Checkpatch warns about 98 too long lines. Some of them could be fixed easily.
This looks scary:
trace_binder_transaction_fd(t, fp->handle, target_fd); binder_debug(BINDER_DEBUG_TRANSACTION, " fd %d -> %d\n", fp->handle, target_fd); /* TODO: fput? */ fp->handle = target_fd; } break;
Could binder_transcation() be split to smaller functions according to CodingStyle? 17 goto targets at the end of function are not exactly easy to read.
ginder_thread_read/write also needs splitting.
binder_ioctl_write_read: just use direct return, no need to goto out if it just returns.
proc->user_buffer_offset = vma->vm_start - (uintptr_t)proc->buffer; mutex_unlock(&binder_mmap_lock);
#ifdef CONFIG_CPU_CACHE_VIPT if (cache_is_vipt_aliasing()) { while (CACHE_COLOUR((vma->vm_start ^ (uint32_t)proc->buffer))) {
Should this be (uintptr_t)?
/*pr_info("binder_mmap: %d %lx-%lx maps %p\n",
Delete the code, don't comment it out. It is on more than one place.
static void print_binder_thread(struct seq_file *m, struct binder_thread *thread, int print_always) { struct binder_transaction *t; struct binder_work *w; size_t start_pos = m->count; size_t header_pos;
seq_printf(m, " thread %d: l %02x\n", thread->pid, thread->looper); header_pos = m->count; t = thread->transaction_stack; while (t) { if (t->from == thread) { print_binder_transaction(m, " outgoing transaction", t); t = t->from_parent;
Is anyone depending on the debugfs files? Can it be deleted?
Code indentation is "interesting" in binder_thread_read(). See the "} break;" lines. {}s should not be needed...?
I don't think this code would get merged if it was submitted for normal inclusion in kernel. I don't think it is good idea to push it through the back door, without documenting what it does and without patches even going to the lists.
Pavel
-- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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