lkml.org 
[lkml]   [2019]   [Jul]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[patch 18/18] x86/apic/x2apic: Add conditional IPI shorthands support
Use the shorthand broadcast delivery if the static key controlling it is
enabled. If not use the regular one by one IPI mechanism.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/kernel/apic/local.h | 1 +
arch/x86/kernel/apic/x2apic_cluster.c | 10 ++++++++--
arch/x86/kernel/apic/x2apic_phys.c | 18 ++++++++++++++++--
3 files changed, 25 insertions(+), 4 deletions(-)

--- a/arch/x86/kernel/apic/local.h
+++ b/arch/x86/kernel/apic/local.h
@@ -23,6 +23,7 @@ unsigned int x2apic_get_apic_id(unsigned
u32 x2apic_set_apic_id(unsigned int id);
int x2apic_phys_pkg_id(int initial_apicid, int index_msb);
void x2apic_send_IPI_self(int vector);
+void __x2apic_send_IPI_shorthand(int vector, u32 which);

/* IPI */

--- a/arch/x86/kernel/apic/x2apic_cluster.c
+++ b/arch/x86/kernel/apic/x2apic_cluster.c
@@ -82,12 +82,18 @@ x2apic_send_IPI_mask_allbutself(const st

static void x2apic_send_IPI_allbutself(int vector)
{
- __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLBUT);
+ if (static_branch_likely(&apic_use_ipi_shorthand))
+ __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
+ else
+ __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLBUT);
}

static void x2apic_send_IPI_all(int vector)
{
- __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
+ if (static_branch_likely(&apic_use_ipi_shorthand))
+ __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
+ else
+ __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
}

static u32 x2apic_calc_apicid(unsigned int cpu)
--- a/arch/x86/kernel/apic/x2apic_phys.c
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -75,12 +75,18 @@ static void

static void x2apic_send_IPI_allbutself(int vector)
{
- __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLBUT);
+ if (static_branch_likely(&apic_use_ipi_shorthand))
+ __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
+ else
+ __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLBUT);
}

static void x2apic_send_IPI_all(int vector)
{
- __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
+ if (static_branch_likely(&apic_use_ipi_shorthand))
+ __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
+ else
+ __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
}

static void init_x2apic_ldr(void)
@@ -112,6 +118,14 @@ void __x2apic_send_IPI_dest(unsigned int
native_x2apic_icr_write(cfg, apicid);
}

+void __x2apic_send_IPI_shorthand(int vector, u32 which)
+{
+ unsigned long cfg = __prepare_ICR(which, vector, 0);
+
+ x2apic_wrmsr_fence();
+ native_x2apic_icr_write(cfg, 0);
+}
+
unsigned int x2apic_get_apic_id(unsigned long id)
{
return id;

\
 
 \ /
  Last update: 2019-07-03 13:05    [W:0.093 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site