x86/apic: Nuke empty init_apic_ldr() callbacks

apic::init_apic_ldr() is only invoked when the APIC is initialized. So
there is really no point in having:

  - Default empty callbacks all over the place

  - Two implementations of the actual LDR init function where one is
    just unreadable gunk but does exactly the same as the other.

Make the apic::init_apic_ldr() invocation conditional, remove the empty
callbacks and consolidate the two implementation into one.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index f6541a22bc696b59babe03440c94706c264682ca..f8a36319626ae2f9be72afd41d6f8ececf7062f8 100644 (file)
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -445,8 +445,6 @@ extern void generic_bigsmp_probe(void);
 
 #include <asm/smp.h>
 
-#define APIC_DFR_VALUE (APIC_DFR_FLAT)
-
 extern struct apic apic_noop;
 
 static inline unsigned int read_apic_id(void)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 24912b2279ded344b39b45f5ad0ea0745a520d12..622dd60229e5703a59b153b88ccf5208410af637 100644 (file)
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1578,9 +1578,12 @@ static void setup_local_APIC(void)
        /*
         * Intel recommends to set DFR, LDR and TPR before enabling
         * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
-        * document number 292116).  So here it goes...
+        * document number 292116).
+        *
+        * Except for APICs which operate in physical destination mode.
         */
-       apic->init_apic_ldr();
+       if (apic->init_apic_ldr)
+               apic->init_apic_ldr();
 
        /*
         * Set Task Priority to 'accept all except vectors 0-31'.  An APIC

diff --git a/arch/x86/kernel/apic/apic_common.c b/arch/x86/kernel/apic/apic_common.c
index 41528bb3a608a8435527df193e94af9355da7e3d..d55fdb33b8e5d4fa5fc0fa81348f0d4b59c4ac4e 100644 (file)
--- a/arch/x86/kernel/apic/apic_common.c
+++ b/arch/x86/kernel/apic/apic_common.c
@@ -6,6 +6,8 @@
 #include <linux/irq.h>
 #include <asm/apic.h>
 
+#include "local.h"
+
 u32 apic_default_calc_apicid(unsigned int cpu)
 {
        return per_cpu(x86_cpu_to_apicid, cpu);
@@ -39,3 +41,17 @@ int default_apic_id_valid(u32 apicid)
 {
        return (apicid < 255);
 }
+
+/*
+ * Set up the logical destination ID when the APIC operates in logical
+ * destination mode.
+ */
+void default_init_apic_ldr(void)
+{
+       unsigned long val;
+
+       apic_write(APIC_DFR, APIC_DFR_FLAT);
+       val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
+       val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
+       apic_write(APIC_LDR, val);
+}

diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c
index 00482cf8255a45bb5f90edac10c26bde1d31ee99..4ddced9005d368b4e440667c29cc79defd65ebca 100644 (file)
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -28,26 +28,6 @@ static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
        return 1;
 }
 
-/*
- * Set up the logical destination ID.
- *
- * Intel recommends to set DFR, LDR and TPR before enabling
- * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
- * document number 292116).  So here it goes...
- */
-void flat_init_apic_ldr(void)
-{
-       unsigned long val;
-       unsigned long num, id;
-
-       num = smp_processor_id();
-       id = 1UL << num;
-       apic_write(APIC_DFR, APIC_DFR_FLAT);
-       val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
-       val |= SET_APIC_LOGICAL_ID(id);
-       apic_write(APIC_LDR, val);
-}
-
 static void _flat_send_IPI_mask(unsigned long mask, int vector)
 {
        unsigned long flags;
@@ -119,7 +99,7 @@ static struct apic apic_flat __ro_after_init = {
        .disable_esr                    = 0,
 
        .check_apicid_used              = NULL,
-       .init_apic_ldr                  = flat_init_apic_ldr,
+       .init_apic_ldr                  = default_init_apic_ldr,
        .ioapic_phys_id_map             = NULL,
        .setup_apic_routing             = NULL,
        .cpu_present_to_apicid          = default_cpu_present_to_apicid,
@@ -175,15 +155,6 @@ static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
        return 0;
 }
 
-static void physflat_init_apic_ldr(void)
-{
-       /*
-        * LDR and DFR are not involved in physflat mode, rather:
-        * "In physical destination mode, the destination processor is
-        * specified by its local APIC ID [...]." (Intel SDM, 10.6.2.1)
-        */
-}
-
 static int physflat_probe(void)
 {
        if (apic == &apic_physflat || num_possible_cpus() > 8 ||
@@ -207,7 +178,6 @@ static struct apic apic_physflat __ro_after_init = {
        .disable_esr                    = 0,
 
        .check_apicid_used              = NULL,
-       .init_apic_ldr                  = physflat_init_apic_ldr,
        .ioapic_phys_id_map             = NULL,
        .setup_apic_routing             = NULL,
        .cpu_present_to_apicid          = default_cpu_present_to_apicid,

diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c
index ccd74e8016fc7383ea0665542d3308bec8752289..dee9e9c73ad93b173ebf26869f0a76049056c1d3 100644 (file)
--- a/arch/x86/kernel/apic/apic_noop.c
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -14,7 +14,6 @@
 
 #include <asm/apic.h>
 
-static void noop_init_apic_ldr(void) { }
 static void noop_send_IPI(int cpu, int vector) { }
 static void noop_send_IPI_mask(const struct cpumask *cpumask, int vector) { }
 static void noop_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector) { }
@@ -94,7 +93,6 @@ struct apic apic_noop __ro_after_init = {
        .disable_esr                    = 0,
 
        .check_apicid_used              = default_check_apicid_used,
-       .init_apic_ldr                  = noop_init_apic_ldr,
        .ioapic_phys_id_map             = default_ioapic_phys_id_map,
        .setup_apic_routing             = NULL,
        .cpu_present_to_apicid          = default_cpu_present_to_apicid,

diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c
index de16fde975681cf7590181d5b694d939aa83301f..d96d74cc8e8ec445a25511b90c669c75409f97ed 100644 (file)
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -252,7 +252,6 @@ static const struct apic apic_numachip1 __refconst = {
        .disable_esr                    = 0,
 
        .check_apicid_used              = NULL,
-       .init_apic_ldr                  = flat_init_apic_ldr,
        .ioapic_phys_id_map             = NULL,
        .setup_apic_routing             = NULL,
        .cpu_present_to_apicid          = default_cpu_present_to_apicid,
@@ -297,7 +296,6 @@ static const struct apic apic_numachip2 __refconst = {
        .disable_esr                    = 0,
 
        .check_apicid_used              = NULL,
-       .init_apic_ldr                  = flat_init_apic_ldr,
        .ioapic_phys_id_map             = NULL,
        .setup_apic_routing             = NULL,
        .cpu_present_to_apicid          = default_cpu_present_to_apicid,

diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c
index aba8ce1d3f2482a951dec7ba1aff42da69c955f5..c688af49bf987b95d8958fd2ce8895e92fe87006 100644 (file)
--- a/arch/x86/kernel/apic/bigsmp_32.c
+++ b/arch/x86/kernel/apic/bigsmp_32.c
@@ -28,14 +28,6 @@ static bool bigsmp_check_apicid_used(physid_mask_t *map, int apicid)
        return false;
 }
 
-/*
- * bigsmp enables physical destination mode
- * and doesn't use LDR and DFR
- */
-static void bigsmp_init_apic_ldr(void)
-{
-}
-
 static void bigsmp_setup_apic_routing(void)
 {
        printk(KERN_INFO
@@ -108,7 +100,6 @@ static struct apic apic_bigsmp __ro_after_init = {
        .disable_esr                    = 1,
 
        .check_apicid_used              = bigsmp_check_apicid_used,
-       .init_apic_ldr                  = bigsmp_init_apic_ldr,
        .ioapic_phys_id_map             = bigsmp_ioapic_phys_id_map,
        .setup_apic_routing             = bigsmp_setup_apic_routing,
        .cpu_present_to_apicid          = default_cpu_present_to_apicid,

diff --git a/arch/x86/kernel/apic/local.h b/arch/x86/kernel/apic/local.h
index ad96c1aece2fb2da718eb39fd19de1fe96df1d74..c14674146cfefc22538010d91fd8bd3ace4d9abb 100644 (file)
--- a/arch/x86/kernel/apic/local.h
+++ b/arch/x86/kernel/apic/local.h
@@ -13,9 +13,6 @@
 #include <asm/irq_vectors.h>
 #include <asm/apic.h>
 
-/* APIC flat 64 */
-void flat_init_apic_ldr(void);
-
 /* X2APIC */
 int x2apic_apic_id_valid(u32 apicid);
 int x2apic_apic_id_registered(void);
@@ -46,6 +43,8 @@ static inline unsigned int __prepare_ICR(unsigned int shortcut, int vector,
        return icr;
 }
 
+void default_init_apic_ldr(void);
+
 void __default_send_IPI_shortcut(unsigned int shortcut, int vector);
 
 /*

diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index 706a8447ac1714ecc211d60311d16cf13bbc7fe4..68fc220efb95f9ac76c291bc0ef532075fc0c783 100644 (file)
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -32,21 +32,6 @@ static int default_apic_id_registered(void)
        return physid_isset(read_apic_id(), phys_cpu_present_map);
 }
 
-/*
- * Set up the logical destination ID.  Intel recommends to set DFR, LDR and
- * TPR before enabling an APIC.  See e.g. "AP-388 82489DX User's Manual"
- * (Intel document number 292116).
- */
-static void default_init_apic_ldr(void)
-{
-       unsigned long val;
-
-       apic_write(APIC_DFR, APIC_DFR_VALUE);
-       val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
-       val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
-       apic_write(APIC_LDR, val);
-}
-
 static int default_phys_pkg_id(int cpuid_apic, int index_msb)
 {
        return cpuid_apic >> index_msb;

diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c
index 9cf32ce779be58bee6f5053c2babf1caae6b0872..c3c2e9814ea1927c32b0423b5ee94cf0f548627b 100644 (file)
--- a/arch/x86/kernel/apic/x2apic_phys.c
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -91,10 +91,6 @@ static void x2apic_send_IPI_all(int vector)
        __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
 }
 
-static void init_x2apic_ldr(void)
-{
-}
-
 static int x2apic_phys_probe(void)
 {
        if (!x2apic_mode)
@@ -169,7 +165,6 @@ static struct apic apic_x2apic_phys __ro_after_init = {
        .disable_esr                    = 0,
 
        .check_apicid_used              = NULL,
-       .init_apic_ldr                  = init_x2apic_ldr,
        .ioapic_phys_id_map             = NULL,
        .setup_apic_routing             = NULL,
        .cpu_present_to_apicid          = default_cpu_present_to_apicid,

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 8b14451611d431d8f9d5d300019b386d8b2a30ae..ab17e588fd9779d779052e8b78b8ccaefdc4ee54 100644 (file)
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -788,10 +788,6 @@ static int uv_apic_id_registered(void)
        return 1;
 }
 
-static void uv_init_apic_ldr(void)
-{
-}
-
 static u32 apic_uv_calc_apicid(unsigned int cpu)
 {
        return apic_default_calc_apicid(cpu);
@@ -841,7 +837,6 @@ static struct apic apic_x2apic_uv_x __ro_after_init = {
        .disable_esr                    = 0,
 
        .check_apicid_used              = NULL,
-       .init_apic_ldr                  = uv_init_apic_ldr,
        .ioapic_phys_id_map             = NULL,
        .setup_apic_routing             = NULL,
        .cpu_present_to_apicid          = default_cpu_present_to_apicid,

diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
index c8240afca77cf80f259e1bb390749cb80d4e63a8..1ff8f75e5c88b7f8fcd27c046f71eb9d74356684 100644 (file)
--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -149,7 +149,6 @@ static struct apic xen_pv_apic = {
        .disable_esr                    = 0,
 
        .check_apicid_used              = default_check_apicid_used, /* Used on 32-bit */
-       .init_apic_ldr                  = xen_noop, /* setup_local_APIC calls it */
        .ioapic_phys_id_map             = default_ioapic_phys_id_map, /* Used on 32-bit */
        .setup_apic_routing             = NULL,
        .cpu_present_to_apicid          = xen_cpu_present_to_apicid,