x86, UV: Remove UV delay in starting slave cpus
Subsystems (2)
PATCH 1/1 x86, UV: Remove UV delay in starting slave cpus
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 <[email protected]>
--- arch/x86/kernel/apic/x2apic_uv_x.c | 1 - 1 file changed, 1 deletion(-)
arch/x86/kernel/apic/x2apic_uv_x.c +0 -1
@@ -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) |
Commit-ID: 05e33fc20ea5e493a2a1e7f1d04f43cdf89f83ed Gitweb: http://git.kernel.org/tip/05e33fc20ea5e493a2a1e7f1d04f43cdf89f83ed Author: Jack Steiner <[email protected]> AuthorDate: Fri, 5 Aug 2011 09:09:00 -0500 Committer: Ingo Molnar <[email protected]> CommitDate: Fri, 5 Aug 2011 23:48:34 +0200
x86, UV: Remove UV delay in starting slave cpus
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 <[email protected]>
Cc <[email protected]>
Signed-off-by Ingo Molnar <[email protected]>
--- arch/x86/kernel/apic/x2apic_uv_x.c | 1 - 1 files changed, 0 insertions(+), 1 deletions(-)
arch/x86/kernel/apic/x2apic_uv_x.c +0 -1
@@ -207,7 +207,6 @@ 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) |