From 10e30e21dbe47702c1580ee315de6bd79fe8bcdf Mon Sep 17 00:00:00 2001 From: Luming Yu Date: Fri, 29 Sep 2017 22:00:44 +0800 Subject: [PATCH v1 3/9] early pt: boot option to enable early pt boot option "early_pt" to enable early pt Signed-off-by: Luming Yu --- arch/x86/events/intel/early_pt.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/x86/events/intel/early_pt.c b/arch/x86/events/intel/early_pt.c index 67513ed..16ed03c 100644 --- a/arch/x86/events/intel/early_pt.c +++ b/arch/x86/events/intel/early_pt.c @@ -42,6 +42,8 @@ static int early_pt_buffer_order = 9; static bool single_range = true; +static bool early_pt_enabled = false; + static DEFINE_PER_CPU(bool, early_pt_running); static DEFINE_PER_CPU(u64, pt_offset); static DEFINE_PER_CPU(u64, pt_buffer_cpu); @@ -201,6 +203,8 @@ static int early_pt_init(void) { int err; + if (!early_pt_enabled) + return 0; err = early_pt_cpuid_caps(); if (err < 0) { pr_info("early_pt_init: no feature available\n"); @@ -214,6 +218,8 @@ static int late_pt_init(void) int err; unsigned int i; + if (!early_pt_enabled) + return 0; for_each_online_cpu(i) { if (!per_cpu(early_pt_running, i)) { pr_err("late_pt_init: failed, early pt not running\n"); @@ -335,3 +341,10 @@ static struct miscdevice early_pt_miscdev = { &early_pt_fops }; +static int __init early_pt_enable(char *str) +{ + early_pt_enabled = true; + return 0; +} +early_param("early_pt", early_pt_enable); + -- 2.7.5