Commit-ID: 2fe9a5c6ade4dfb53ff1c137cca3828d9d1d0948 Gitweb: http://git.kernel.org/tip/2fe9a5c6ade4dfb53ff1c137cca3828d9d1d0948 Author: Andrew Banman <aban...@hpe.com> AuthorDate: Thu, 20 Jul 2017 17:05:51 -0500 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Fri, 21 Jul 2017 09:56:25 +0200
x86/platform/uv/BAU: Disable BAU on single hub configurations The BAU confers no benefit to a UV system running with only one hub/socket. Permanently disable the BAU driver if there are less than two hubs online to avoid BAU overhead. We have observed failed boots on single-socket UV4 systems caused by BAU that are avoided with this patch. Also, while at it, consolidate initialization error blocks and fix a memory leak. Signed-off-by: Andrew Banman <aban...@hpe.com> Acked-by: Russ Anderson <r...@hpe.com> Acked-by: Mike Travis <mike.tra...@hpe.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: tony.er...@hpe.com Link: http://lkml.kernel.org/r/1500588351-78016-1-git-send-email-aban...@hpe.com [ Minor cleanups. ] Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/platform/uv/tlb_uv.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c index fd87591..3e4bdb4 100644 --- a/arch/x86/platform/uv/tlb_uv.c +++ b/arch/x86/platform/uv/tlb_uv.c @@ -2221,13 +2221,17 @@ static int __init uv_bau_init(void) else if (is_uv1_hub()) ops = uv1_bau_ops; + nuvhubs = uv_num_possible_blades(); + if (nuvhubs < 2) { + pr_crit("UV: BAU disabled - insufficient hub count\n"); + goto err_bau_disable; + } + for_each_possible_cpu(cur_cpu) { mask = &per_cpu(uv_flush_tlb_mask, cur_cpu); zalloc_cpumask_var_node(mask, GFP_KERNEL, cpu_to_node(cur_cpu)); } - nuvhubs = uv_num_possible_blades(); - uv_base_pnode = 0x7fffffff; for (uvhub = 0; uvhub < nuvhubs; uvhub++) { cpus = uv_blade_nr_possible_cpus(uvhub); @@ -2240,9 +2244,8 @@ static int __init uv_bau_init(void) enable_timeouts(); if (init_per_cpu(nuvhubs, uv_base_pnode)) { - set_bau_off(); - nobau_perm = 1; - return 0; + pr_crit("UV: BAU disabled - per CPU init failed\n"); + goto err_bau_disable; } vector = UV_BAU_MESSAGE; @@ -2268,6 +2271,16 @@ static int __init uv_bau_init(void) } return 0; + +err_bau_disable: + + for_each_possible_cpu(cur_cpu) + free_cpumask_var(per_cpu(uv_flush_tlb_mask, cur_cpu)); + + set_bau_off(); + nobau_perm = 1; + + return -EINVAL; } core_initcall(uv_bau_init); fs_initcall(uv_ptc_init);
