46 lines
1.4 KiB
Diff
46 lines
1.4 KiB
Diff
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From a312877651e18175726e33e4530307880d249aa5 Mon Sep 17 00:00:00 2001
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From: Arjan van de Ven <arjan@linux.intel.com>
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Date: Wed, 11 Feb 2015 17:28:14 -0600
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Subject: [PATCH 08/22] smpboot: reuse timer calibration
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NO point recalibrating for known-constant tsc... saves 200ms+ of boot time.
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Author: Arjan van de Ven <arjan@linux.intel.com>
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Signed-off-by: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
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---
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arch/x86/kernel/smpboot.c | 2 +-
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arch/x86/kernel/tsc.c | 3 +++
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2 files changed, 4 insertions(+), 1 deletion(-)
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diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
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index 36171bcd..7f4e9cdf 100644
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--- a/arch/x86/kernel/smpboot.c
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+++ b/arch/x86/kernel/smpboot.c
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@@ -731,7 +731,7 @@ wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
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pr_debug("Waiting for send to finish...\n");
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send_status = safe_apic_wait_icr_idle();
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- udelay(init_udelay);
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+ udelay(100);
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pr_debug("Deasserting INIT\n");
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diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
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index 6e57edf3..94ab049f 100644
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--- a/arch/x86/kernel/tsc.c
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+++ b/arch/x86/kernel/tsc.c
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@@ -1390,6 +1390,9 @@ unsigned long calibrate_delay_is_known(void)
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if (!mask)
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return 0;
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+ if (cpu !=0)
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+ return cpu_data(0).loops_per_jiffy;
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+
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sibling = cpumask_any_but(mask, cpu);
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if (sibling < nr_cpu_ids)
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return cpu_data(sibling).loops_per_jiffy;
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--
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2.11.0
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