[tip: x86/apic] x86/apic: Move safe wait_icr_idle() next to apic_mem_wait_icr_idle()

From: tip-bot2 for Thomas Gleixner
Date: Wed Aug 09 2023 - 16:37:13 EST


The following commit has been merged into the x86/apic branch of tip:

Commit-ID: e7b6a023d2c90fcd540a29bbf5bd4e1b816e613c
Gitweb: https://git.kernel.org/tip/e7b6a023d2c90fcd540a29bbf5bd4e1b816e613c
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Tue, 08 Aug 2023 15:04:06 -07:00
Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CommitterDate: Wed, 09 Aug 2023 11:58:29 -07:00

x86/apic: Move safe wait_icr_idle() next to apic_mem_wait_icr_idle()

Move it next to apic_mem_wait_icr_idle(), rename it so that it's clear what
it does and rewrite it in readable form.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Tested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Tested-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>
Tested-by: Juergen Gross <jgross@xxxxxxxx> # Xen PV (dom0 and unpriv. guest)
---
arch/x86/include/asm/apic.h | 1 -
arch/x86/kernel/apic/apic.c | 17 -----------------
arch/x86/kernel/apic/apic_flat_64.c | 4 ++--
arch/x86/kernel/apic/bigsmp_32.c | 2 +-
arch/x86/kernel/apic/ipi.c | 19 +++++++++++++++++--
arch/x86/kernel/apic/local.h | 1 +
arch/x86/kernel/apic/probe_32.c | 2 +-
7 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index dd0a05d..49b6c7e 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -98,7 +98,6 @@ static inline u32 native_apic_mem_read(u32 reg)
return *((volatile u32 *)(APIC_BASE + reg));
}

-extern u32 native_safe_apic_wait_icr_idle(void);
extern void native_apic_icr_write(u32 low, u32 id);
extern u64 native_apic_icr_read(void);

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index ab26a61..80a31f2 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -240,23 +240,6 @@ static void __init apic_disable(void)
apic = &apic_noop;
}

-u32 native_safe_apic_wait_icr_idle(void)
-{
- u32 send_status;
- int timeout;
-
- timeout = 0;
- do {
- send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
- if (!send_status)
- break;
- inc_irq_stat(icr_read_retry_count);
- udelay(100);
- } while (timeout++ < 1000);
-
- return send_status;
-}
-
void native_apic_icr_write(u32 low, u32 id)
{
unsigned long flags;
diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c
index 57d3afb..1da865f 100644
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -112,7 +112,7 @@ static struct apic apic_flat __ro_after_init = {
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
.wait_icr_idle = apic_mem_wait_icr_idle,
- .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
+ .safe_wait_icr_idle = apic_mem_wait_icr_idle_timeout,
};

/*
@@ -188,7 +188,7 @@ static struct apic apic_physflat __ro_after_init = {
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
.wait_icr_idle = apic_mem_wait_icr_idle,
- .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
+ .safe_wait_icr_idle = apic_mem_wait_icr_idle_timeout,
};

/*
diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c
index 57077fc..32984bf 100644
--- a/arch/x86/kernel/apic/bigsmp_32.c
+++ b/arch/x86/kernel/apic/bigsmp_32.c
@@ -109,7 +109,7 @@ static struct apic apic_bigsmp __ro_after_init = {
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
.wait_icr_idle = apic_mem_wait_icr_idle,
- .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
+ .safe_wait_icr_idle = apic_mem_wait_icr_idle_timeout,
};

bool __init apic_bigsmp_possible(bool cmdline_override)
diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c
index e0e0567..460df02 100644
--- a/arch/x86/kernel/apic/ipi.c
+++ b/arch/x86/kernel/apic/ipi.c
@@ -1,7 +1,9 @@
// SPDX-License-Identifier: GPL-2.0

#include <linux/cpumask.h>
+#include <linux/delay.h>
#include <linux/smp.h>
+
#include <asm/io_apic.h>

#include "local.h"
@@ -102,6 +104,19 @@ static inline int __prepare_ICR2(unsigned int mask)
return SET_XAPIC_DEST_FIELD(mask);
}

+u32 apic_mem_wait_icr_idle_timeout(void)
+{
+ int cnt;
+
+ for (cnt = 0; cnt < 1000; cnt++) {
+ if (!(apic_read(APIC_ICR) & APIC_ICR_BUSY))
+ return 0;
+ inc_irq_stat(icr_read_retry_count);
+ udelay(100);
+ }
+ return APIC_ICR_BUSY;
+}
+
void apic_mem_wait_icr_idle(void)
{
while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY)
@@ -135,7 +150,7 @@ static void __default_send_IPI_shortcut(unsigned int shortcut, int vector)
* to stop the others before launching the kdump kernel.
*/
if (unlikely(vector == NMI_VECTOR))
- safe_apic_wait_icr_idle();
+ apic_mem_wait_icr_idle_timeout();
else
apic_mem_wait_icr_idle();

@@ -152,7 +167,7 @@ void __default_send_IPI_dest_field(unsigned int dest_mask, int vector,
{
/* See comment in __default_send_IPI_shortcut() */
if (unlikely(vector == NMI_VECTOR))
- safe_apic_wait_icr_idle();
+ apic_mem_wait_icr_idle_timeout();
else
apic_mem_wait_icr_idle();

diff --git a/arch/x86/kernel/apic/local.h b/arch/x86/kernel/apic/local.h
index 2eb49d4..98cfe78 100644
--- a/arch/x86/kernel/apic/local.h
+++ b/arch/x86/kernel/apic/local.h
@@ -45,6 +45,7 @@ static inline unsigned int __prepare_ICR(unsigned int shortcut, int vector,
void default_init_apic_ldr(void);

void apic_mem_wait_icr_idle(void);
+u32 apic_mem_wait_icr_idle_timeout(void);

/*
* This is used to send an IPI with no shorthand notation (the destination is
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index 52f3c6f..a861a77 100644
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -65,7 +65,7 @@ static struct apic apic_default __ro_after_init = {
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
.wait_icr_idle = apic_mem_wait_icr_idle,
- .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
+ .safe_wait_icr_idle = apic_mem_wait_icr_idle_timeout,
};

apic_driver(apic_default);