diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/x86/kernel/tracepoint.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/x86/kernel/tracepoint.c')
-rw-r--r-- | kernel/arch/x86/kernel/tracepoint.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/kernel/arch/x86/kernel/tracepoint.c b/kernel/arch/x86/kernel/tracepoint.c new file mode 100644 index 000000000..1c113db9e --- /dev/null +++ b/kernel/arch/x86/kernel/tracepoint.c @@ -0,0 +1,59 @@ +/* + * Code for supporting irq vector tracepoints. + * + * Copyright (C) 2013 Seiji Aguchi <seiji.aguchi@hds.com> + * + */ +#include <asm/hw_irq.h> +#include <asm/desc.h> +#include <linux/atomic.h> + +atomic_t trace_idt_ctr = ATOMIC_INIT(0); +struct desc_ptr trace_idt_descr = { NR_VECTORS * 16 - 1, + (unsigned long) trace_idt_table }; + +/* No need to be aligned, but done to keep all IDTs defined the same way. */ +gate_desc trace_idt_table[NR_VECTORS] __page_aligned_bss; + +static int trace_irq_vector_refcount; +static DEFINE_MUTEX(irq_vector_mutex); + +static void set_trace_idt_ctr(int val) +{ + atomic_set(&trace_idt_ctr, val); + /* Ensure the trace_idt_ctr is set before sending IPI */ + wmb(); +} + +static void switch_idt(void *arg) +{ + unsigned long flags; + + local_irq_save(flags); + load_current_idt(); + local_irq_restore(flags); +} + +void trace_irq_vector_regfunc(void) +{ + mutex_lock(&irq_vector_mutex); + if (!trace_irq_vector_refcount) { + set_trace_idt_ctr(1); + smp_call_function(switch_idt, NULL, 0); + switch_idt(NULL); + } + trace_irq_vector_refcount++; + mutex_unlock(&irq_vector_mutex); +} + +void trace_irq_vector_unregfunc(void) +{ + mutex_lock(&irq_vector_mutex); + trace_irq_vector_refcount--; + if (!trace_irq_vector_refcount) { + set_trace_idt_ctr(0); + smp_call_function(switch_idt, NULL, 0); + switch_idt(NULL); + } + mutex_unlock(&irq_vector_mutex); +} |