Re: [PATCH 0/2] Ajust lockdep static allocations

From: Babu Moger
Date: Fri Sep 23 2016 - 11:16:42 EST




On 9/23/2016 10:04 AM, Peter Zijlstra wrote:
On Fri, Sep 23, 2016 at 09:50:52AM -0500, Babu Moger wrote:
Why can't you boot? You have that little memories? 4MB doesn't seem like
a worthwhile amount of memory.

Also, you didn't say. This seems a somewhat crucial point.
Correct, We can't boot with lockdep. Sorry I did not make that clear.
We have a limit on static size of the kernel.
This stuff should be in .bss not .data. It should not affect the static
size at all. Or am I misunderstanding things?
Here it is.
$ ./scripts/bloat-o-meter vmlinux.lockdep.small vmlinux.lockdep.big
add/remove: 0/0 grow/shrink: 5/0 up/down: 4653056/0 (4653056)
function old new delta
stack_trace 2097152 4194304 +2097152
lock_chains 1048576 2097152 +1048576
list_entries 1048576 2097152 +1048576
chain_hlocks 327680 655360 +327680
chainhash_table 131072 262144 +131072
Total: Before=21046200, After=25699256, chg 22.000000%