Messages in this thread Patch in this message | | | Date | Fri, 5 Aug 2011 09:09:00 -0500 | From | Jack Steiner <> | Subject | [PATCH] x86, UV: Remove UV delay in starting slave cpus |
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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>
--- arch/x86/kernel/apic/x2apic_uv_x.c | 1 - 1 file changed, 1 deletion(-)
Index: linux/arch/x86/kernel/apic/x2apic_uv_x.c =================================================================== --- linux.orig/arch/x86/kernel/apic/x2apic_uv_x.c 2011-08-05 08:22:42.511980932 -0500 +++ linux/arch/x86/kernel/apic/x2apic_uv_x.c 2011-08-05 08:23:27.488613896 -0500 @@ -207,7 +207,6 @@ static int __cpuinit uv_wakeup_secondary ((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) |
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