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Date: Mon, 7 Nov 2016 14:20:40 +0100
From: Borislav Petkov <bp@...en8.de>
To: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Cc: linux-kernel@...r.kernel.org, rt@...utronix.de,
Tony Luck <tony.luck@...el.com>, linux-edac@...r.kernel.org,
x86@...nel.org, Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH 21/25] x86/mcheck: Split threshold_cpu_callback into two
callbacks
On Thu, Nov 03, 2016 at 03:50:17PM +0100, Sebastian Andrzej Siewior wrote:
> The threshold_cpu_callback callbacks looks like one of the notifier and
> its arguments are almost the same. Split this out and have one ONLINE
> and one DEAD callback. This will come handy later once the main code
> gets changed to use the callback mechanism.
> Also, handle threshold_cpu_callback_online() return value so we don't
> continue if the function fails.
>
> Cc: Tony Luck <tony.luck@...el.com>
> Cc: Borislav Petkov <bp@...en8.de>
> Cc: linux-edac@...r.kernel.org
> Cc: x86@...nel.org
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
> Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
> ---
> arch/x86/include/asm/mce.h | 3 ++-
> arch/x86/kernel/cpu/mcheck/mce.c | 18 +++++++++++++-----
> arch/x86/kernel/cpu/mcheck/mce_amd.c | 24 ++++--------------------
> 3 files changed, 19 insertions(+), 26 deletions(-)
...
> -void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu);
> +int (*threshold_cpu_callback_online)(unsigned int cpu);
> +int (*threshold_cpu_callback_dead)(unsigned int cpu);
Let's get rid of those pointers and pointer testing and export the
create/remove functions directly.
How's that? It builds here.
---
Index: b/arch/x86/include/asm/mce.h
===================================================================
--- a/arch/x86/include/asm/mce.h 2016-11-07 14:06:40.246518729 +0100
+++ b/arch/x86/include/asm/mce.h 2016-11-07 14:17:36.770529205 +0100
@@ -292,9 +292,9 @@ void do_machine_check(struct pt_regs *,
/*
* Threshold handler
*/
-
extern void (*mce_threshold_vector)(void);
-extern void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu);
+extern int mce_threshold_create_device(unsigned int cpu);
+extern int mce_threshold_remove_device(unsigned int cpu);
/* Deferred error interrupt handler */
extern void (*deferred_error_int_vector)(void);
Index: b/arch/x86/kernel/cpu/mcheck/mce.c
===================================================================
--- a/arch/x86/kernel/cpu/mcheck/mce.c 2016-11-07 14:06:40.246518729 +0100
+++ b/arch/x86/kernel/cpu/mcheck/mce.c 2016-11-07 14:17:06.186528717 +0100
@@ -2291,8 +2291,6 @@ static struct bus_type mce_subsys = {
DEFINE_PER_CPU(struct device *, mce_device);
-void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu);
-
static inline struct mce_bank *attr_to_bank(struct device_attribute *attr)
{
return container_of(attr, struct mce_bank, attr);
@@ -2548,13 +2546,17 @@ mce_cpu_callback(struct notifier_block *
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_ONLINE:
+
mce_device_create(cpu);
- if (threshold_cpu_callback)
- threshold_cpu_callback(action, cpu);
+
+ if (mce_threshold_create_device(cpu)) {
+ mce_device_remove(cpu);
+ return NOTIFY_BAD;
+ }
+
break;
case CPU_DEAD:
- if (threshold_cpu_callback)
- threshold_cpu_callback(action, cpu);
+ mce_threshold_remove_device(cpu);
mce_device_remove(cpu);
mce_intel_hcpu_update(cpu);
Index: b/arch/x86/kernel/cpu/mcheck/mce_amd.c
===================================================================
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c 2016-11-07 14:06:40.246518729 +0100
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c 2016-11-07 14:18:10.506529743 +0100
@@ -55,6 +55,8 @@
/* Threshold LVT offset is at MSR0xC0000410[15:12] */
#define SMCA_THR_LVT_OFF 0xF000
+static bool thresholding_en;
+
static const char * const th_names[] = {
"load_store",
"insn_fetch",
@@ -1097,10 +1099,13 @@ free_out:
per_cpu(threshold_banks, cpu)[bank] = NULL;
}
-static void threshold_remove_device(unsigned int cpu)
+int mce_threshold_remove_device(unsigned int cpu)
{
unsigned int bank;
+ if (!thresholding_en)
+ return 0;
+
for (bank = 0; bank < mca_cfg.banks; ++bank) {
if (!(per_cpu(bank_map, cpu) & (1 << bank)))
continue;
@@ -1108,15 +1113,19 @@ static void threshold_remove_device(unsi
}
kfree(per_cpu(threshold_banks, cpu));
per_cpu(threshold_banks, cpu) = NULL;
+ return 0;
}
/* create dir/files for all valid threshold banks */
-static int threshold_create_device(unsigned int cpu)
+int mce_threshold_create_device(unsigned int cpu)
{
unsigned int bank;
struct threshold_bank **bp;
int err = 0;
+ if (!thresholding_en)
+ return 0;
+
bp = per_cpu(threshold_banks, cpu);
if (bp)
return 0;
@@ -1136,40 +1145,23 @@ static int threshold_create_device(unsig
}
return err;
err:
- threshold_remove_device(cpu);
+ mce_threshold_remove_device(cpu);
return err;
}
-/* get notified when a cpu comes on/off */
-static void
-amd_64_threshold_cpu_callback(unsigned long action, unsigned int cpu)
-{
- switch (action) {
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- threshold_create_device(cpu);
- break;
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- threshold_remove_device(cpu);
- break;
- default:
- break;
- }
-}
-
static __init int threshold_init_device(void)
{
unsigned lcpu = 0;
/* to hit CPUs online before the notifier is up */
for_each_online_cpu(lcpu) {
- int err = threshold_create_device(lcpu);
+ int err = mce_threshold_create_device(lcpu);
if (err)
return err;
}
- threshold_cpu_callback = amd_64_threshold_cpu_callback;
+
+ thresholding_en = true;
return 0;
}
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
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