x86, UV: Remove UV delay in starting slave cpus

commit 05e33fc20ea5e493a2a1e7f1d04f43cdf89f83ed upstream.

Delete the 10 msec delay between the INIT and SIPI when starting
slave cpus. I can find no requirement for this delay. BIOS also
has similar code sequences without the delay.

Removing the delay reduces boot time by 40 sec. Every bit helps.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Link: http://lkml.kernel.org/r/20110805140900.GA6774@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 25a1b3ccae9f0603b956ce756e219c1f5f003177..2872559ec027927f8e527270fd62f1ef4142edca 100644 (file)
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -144,7 +144,6 @@ static int __cpuinit uv_wakeup_secondary(int phys_apicid, unsigned long start_ri
            ((start_rip << UVH_IPI_INT_VECTOR_SHFT) >> 12) |
            APIC_DM_INIT;
        uv_write_global_mmr64(pnode, UVH_IPI_INT, val);
-       mdelay(10);
 
        val = (1UL << UVH_IPI_INT_SEND_SHFT) |
            (phys_apicid << UVH_IPI_INT_APIC_ID_SHFT) |