sched: move rq_weight data array out of .percpu
Commit 34d76c41 introduced percpu array update_shares_data, size of which
being proportional to NR_CPUS. Unfortunately this blows up ia64 for large
NR_CPUS configuration, as ia64 allows only 64k for .percpu section.
Fix this by allocating this array dynamically and keep only pointer to it
percpu.
The per-cpu handling doesn't impose significant performance penalty on
potentially contented path in tg_shares_up().
...
ffffffff8104337c: 65 48 8b 14 25 20 cd mov %gs:0xcd20,%rdx
ffffffff81043383: 00 00
ffffffff81043385: 48 c7 c0 00 e1 00 00 mov $0xe100,%rax
ffffffff8104338c: 48 c7 45 a0 00 00 00 movq $0x0,-0x60(%rbp)
ffffffff81043393: 00
ffffffff81043394: 48 c7 45 a8 00 00 00 movq $0x0,-0x58(%rbp)
ffffffff8104339b: 00
ffffffff8104339c: 48 01 d0 add %rdx,%rax
ffffffff8104339f: 49 8d 94 24 08 01 00 lea 0x108(%r12),%rdx
ffffffff810433a6: 00
ffffffff810433a7: b9 ff ff ff ff mov $0xffffffff,%ecx
ffffffff810433ac: 48 89 45 b0 mov %rax,-0x50(%rbp)
ffffffff810433b0: bb 00 04 00 00 mov $0x400,%ebx
ffffffff810433b5: 48 89 55 c0 mov %rdx,-0x40(%rbp)
...
After:
...
ffffffff8104337c: 65 8b 04 25 28 cd 00 mov %gs:0xcd28,%eax
ffffffff81043383: 00
ffffffff81043384: 48 98 cltq
ffffffff81043386: 49 8d bc 24 08 01 00 lea 0x108(%r12),%rdi
ffffffff8104338d: 00
ffffffff8104338e: 48 8b 15 d3 7f 76 00 mov 0x767fd3(%rip),%rdx # ffffffff817ab368 <update_shares_data>
ffffffff81043395: 48 8b 34 c5 00 ee 6d mov -0x7e921200(,%rax,8),%rsi
ffffffff8104339c: 81
ffffffff8104339d: 48 c7 45 a0 00 00 00 movq $0x0,-0x60(%rbp)
ffffffff810433a4: 00
ffffffff810433a5: b9 ff ff ff ff mov $0xffffffff,%ecx
ffffffff810433aa: 48 89 7d c0 mov %rdi,-0x40(%rbp)
ffffffff810433ae: 48 c7 45 a8 00 00 00 movq $0x0,-0x58(%rbp)
ffffffff810433b5: 00
ffffffff810433b6: bb 00 04 00 00 mov $0x400,%ebx
ffffffff810433bb: 48 01 f2 add %rsi,%rdx
ffffffff810433be: 48 89 55 b0 mov %rdx,-0x50(%rbp)
...
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Tejun Heo <tj@kernel.org>
1 file changed