x86: UV BAU messaging timeouts
This patch replaces a 'nop' uv_enable_timeouts() in the
UV TLB shootdown code. (somehow, long ago that function got
eviscerated)
If any cpu in the destination node does not get interrupted by the
message and post completion in a reasonable time the hardware
should respond to the sender with an error. This function
enables such timeouts.
Tested on the UV hardware simulator.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
LKML-Reference: <E1LpjXU-00007e-Qh@eag09.americas.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/tlb_uv.c b/arch/x86/kernel/tlb_uv.c
index b833bc6..fced96e 100644
--- a/arch/x86/kernel/tlb_uv.c
+++ b/arch/x86/kernel/tlb_uv.c
@@ -445,24 +445,58 @@
set_irq_regs(old_regs);
}
+/*
+ * uv_enable_timeouts
+ *
+ * Each target blade (i.e. blades that have cpu's) needs to have
+ * shootdown message timeouts enabled. The timeout does not cause
+ * an interrupt, but causes an error message to be returned to
+ * the sender.
+ */
static void uv_enable_timeouts(void)
{
- int i;
int blade;
- int last_blade;
+ int nblades;
int pnode;
- int cur_cpu = 0;
- unsigned long apicid;
+ unsigned long mmr_image;
- last_blade = -1;
- for_each_online_node(i) {
- blade = uv_node_to_blade_id(i);
- if (blade == last_blade)
+ nblades = uv_num_possible_blades();
+
+ for (blade = 0; blade < nblades; blade++) {
+ if (!uv_blade_nr_possible_cpus(blade))
continue;
- last_blade = blade;
- apicid = per_cpu(x86_cpu_to_apicid, cur_cpu);
+
pnode = uv_blade_to_pnode(blade);
- cur_cpu += uv_blade_nr_possible_cpus(i);
+ mmr_image =
+ uv_read_global_mmr64(pnode, UVH_LB_BAU_MISC_CONTROL);
+ /*
+ * Set the timeout period and then lock it in, in three
+ * steps; captures and locks in the period.
+ *
+ * To program the period, the SOFT_ACK_MODE must be off.
+ */
+ mmr_image &= ~((unsigned long)1 <<
+ UV_ENABLE_INTD_SOFT_ACK_MODE_SHIFT);
+ uv_write_global_mmr64
+ (pnode, UVH_LB_BAU_MISC_CONTROL, mmr_image);
+ /*
+ * Set the 4-bit period.
+ */
+ mmr_image &= ~((unsigned long)0xf <<
+ UV_INTD_SOFT_ACK_TIMEOUT_PERIOD_SHIFT);
+ mmr_image |= (UV_INTD_SOFT_ACK_TIMEOUT_PERIOD <<
+ UV_INTD_SOFT_ACK_TIMEOUT_PERIOD_SHIFT);
+ uv_write_global_mmr64
+ (pnode, UVH_LB_BAU_MISC_CONTROL, mmr_image);
+ /*
+ * Subsequent reversals of the timebase bit (3) cause an
+ * immediate timeout of one or all INTD resources as
+ * indicated in bits 2:0 (7 causes all of them to timeout).
+ */
+ mmr_image |= ((unsigned long)1 <<
+ UV_ENABLE_INTD_SOFT_ACK_MODE_SHIFT);
+ uv_write_global_mmr64
+ (pnode, UVH_LB_BAU_MISC_CONTROL, mmr_image);
}
}