[patch V2 30/67] powerpc/numa: Convert to hotplug state machine

Subsystems: cpu hotplug, linux for powerpc (32-bit and 64-bit), the rest

STALE3661d

8 messages, 4 authors, 2016-07-18 · open the first message on its own page

[patch V2 30/67] powerpc/numa: Convert to hotplug state machine

From: Anna-Maria Gleixner <anna-maria@linutronix.de>
Date: 2016-07-13 17:29:37

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bharata B Rao <redacted>
Cc: Christophe Jaillet <redacted>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nikunj A Dadhania <redacted>
Cc: Paul Mackerras <redacted>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <redacted>
Cc: Thomas Gleixner <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 arch/powerpc/mm/numa.c     | 46 ++++++++++++++++------------------------------
 include/linux/cpuhotplug.h |  1 +
 2 files changed, 17 insertions(+), 30 deletions(-)

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 669a15e..d48ac48 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c

@@ -581,30 +581,22 @@ static void verify_cpu_node_mapping(int cpu, int node)
 	}
 }
 
-static int cpu_numa_callback(struct notifier_block *nfb, unsigned long action,
-			     void *hcpu)
+/* Must run before sched domains notifier. */
+static int ppc_numa_cpu_prepare(unsigned int cpu)
 {
-	unsigned long lcpu = (unsigned long)hcpu;
-	int ret = NOTIFY_DONE, nid;
+	int nid;
 
-	switch (action) {
-	case CPU_UP_PREPARE:
-	case CPU_UP_PREPARE_FROZEN:
-		nid = numa_setup_cpu(lcpu);
-		verify_cpu_node_mapping((int)lcpu, nid);
-		ret = NOTIFY_OK;
-		break;
+	nid = numa_setup_cpu(cpu);
+	verify_cpu_node_mapping(cpu, nid);
+	return 0;
+}
+
+static int ppc_numa_cpu_dead(unsigned int cpu)
+{
 #ifdef CONFIG_HOTPLUG_CPU
-	case CPU_DEAD:
-	case CPU_DEAD_FROZEN:
-	case CPU_UP_CANCELED:
-	case CPU_UP_CANCELED_FROZEN:
-		unmap_cpu_from_node(lcpu);
-		ret = NOTIFY_OK;
-		break;
+	unmap_cpu_from_node(cpu);
 #endif
-	}
-	return ret;
+	return 0;
 }
 
 /*

@@ -913,11 +905,6 @@ static void __init dump_numa_memory_topology(void)
 	}
 }
 
-static struct notifier_block ppc64_numa_nb = {
-	.notifier_call = cpu_numa_callback,
-	.priority = 1 /* Must run before sched domains notifier. */
-};
-
 /* Initialize NODE_DATA for a node on the local memory */
 static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
 {

@@ -953,7 +940,7 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
 
 void __init initmem_init(void)
 {
-	int nid, cpu;
+	int nid;
 
 	max_low_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
 	max_pfn = max_low_pfn;

@@ -985,15 +972,14 @@ void __init initmem_init(void)
 	setup_node_to_cpumask_map();
 
 	reset_numa_cpu_lookup_table();
-	register_cpu_notifier(&ppc64_numa_nb);
+
 	/*
 	 * We need the numa_cpu_lookup_table to be accurate for all CPUs,
 	 * even before we online them, so that we can use cpu_to_{node,mem}
 	 * early in boot, cf. smp_prepare_cpus().
 	 */
-	for_each_present_cpu(cpu) {
-		numa_setup_cpu((unsigned long)cpu);
-	}
+	cpuhp_setup_state(CPUHP_POWER_NUMA_PREPARE, "POWER_NUMA_PREPARE",
+			  ppc_numa_cpu_prepare, ppc_numa_cpu_dead);
 }
 
 static int __init early_numa(char *p)

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 7449081..01133ec 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h

@@ -14,6 +14,7 @@ enum cpuhp_state {
 	CPUHP_PERF_SUPERH,
 	CPUHP_X86_HPET_DEAD,
 	CPUHP_WORKQUEUE_PREP,
+	CPUHP_POWER_NUMA_PREPARE,
 	CPUHP_NOTIFY_PREPARE,
 	CPUHP_BRINGUP_CPU,
 	CPUHP_AP_IDLE_DEAD,

-- 
2.8.1

Re: [patch V2 30/67] powerpc/numa: Convert to hotplug state machine

From: Anton Blanchard <hidden>
Date: 2016-07-14 21:43:50

Hi,

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

This is causing an oops on ppc64le QEMU, looks like a NULL pointer:

percpu: Embedded 3 pages/cpu @c00000001fe00000 s145816 r0 d50792 u1048576
Unable to handle kernel paging request for data at address 0x00001e08
Faulting instruction address: 0xc0000000001e6b78
Oops: Kernel access of bad area, sig: 11 [#1]
SMP NR_CPUS=2048 NUMA pSeries
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 4.7.0-rc7-00198-g425209e #14
task: c000000000d82a00 ti: c000000000dc4000 task.ti: c000000000dc4000
NIP: c0000000001e6b78 LR: c0000000001e6df4 CTR: 0000000000000000
REGS: c000000000dc7b60 TRAP: 0300   Not tainted  (4.7.0-rc7-00198-g425209e)
MSR: 8000000002001033 <SF,VEC,ME,IR,DR,RI,LE>  CR: 44000220  XER: 00000000
CFAR: 0000000000008468 DAR: 0000000000001e08 DSISR: 40000000 SOFTE: 0 
GPR00: 0000000000000006 c000000000dc7de0 c000000000dc6c00 0000000000000000 
GPR04: 0000000000000000 0000000000000000 c00000001fe1fb70 0000000000000010 
GPR08: c000000000dfe918 c000000000e50dd0 c000000000e56c00 0000000000000001 
GPR12: 0000000000000000 c00000000fe00000 0000000000000060 0000000000f1d618 
GPR16: 0000000000efccd8 0000000000efcb20 fffffffffffffffd 0000000000000000 
GPR20: 000000001f150000 c000000000dfa8e0 c000000000ccfafc c000000000dfeb18 
GPR24: c000000000dfee34 c000000000ccfaf8 0000000000000000 0000000000000001 
GPR28: c000000000ebad20 c000000000ccfb00 0000000000000000 c00000001fe1fb00 
NIP [c0000000001e6b78] local_memory_node+0x18/0x80
LR [c0000000001e6df4] __build_all_zonelists+0x214/0x2d0
Call Trace:
[c000000000dc7de0] [c0000000001e6ccc] __build_all_zonelists+0xec/0x2d0 (unreliable)
[c000000000dc7e70] [c000000000c39fbc] build_all_zonelists_init+0x1c/0x3c
[c000000000dc7e90] [c000000000282acc] build_all_zonelists+0x17c/0x18c
[c000000000dc7f00] [c000000000c13c54] start_kernel+0x18c/0x514
[c000000000dc7f90] [c000000000008c60] start_here_common+0x20/0xa0
Instruction dump:
38810178 7f63db78 48769171 60000000 4bfffd2c 60420000 3c4c00be 384200a0 
3d420009 78631f24 392aa1d0 7c69182a <81231e08> 38631e00 2b890002 419d001c 

Anton

quoted hunk

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bharata B Rao <redacted>
Cc: Christophe Jaillet <redacted>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nikunj A Dadhania <redacted>
Cc: Paul Mackerras <redacted>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <redacted>
Cc: Thomas Gleixner <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 arch/powerpc/mm/numa.c     | 46
++++++++++++++++------------------------------
include/linux/cpuhotplug.h |  1 + 2 files changed, 17 insertions(+),
30 deletions(-)

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 669a15e..d48ac48 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c

@@ -581,30 +581,22 @@ static void verify_cpu_node_mapping(int cpu,

int node) }
 }
 
-static int cpu_numa_callback(struct notifier_block *nfb, unsigned
long action,
-			     void *hcpu)
+/* Must run before sched domains notifier. */
+static int ppc_numa_cpu_prepare(unsigned int cpu)
 {
-	unsigned long lcpu = (unsigned long)hcpu;
-	int ret = NOTIFY_DONE, nid;
+	int nid;
 
-	switch (action) {
-	case CPU_UP_PREPARE:
-	case CPU_UP_PREPARE_FROZEN:
-		nid = numa_setup_cpu(lcpu);
-		verify_cpu_node_mapping((int)lcpu, nid);
-		ret = NOTIFY_OK;
-		break;
+	nid = numa_setup_cpu(cpu);
+	verify_cpu_node_mapping(cpu, nid);
+	return 0;
+}
+
+static int ppc_numa_cpu_dead(unsigned int cpu)
+{
 #ifdef CONFIG_HOTPLUG_CPU
-	case CPU_DEAD:
-	case CPU_DEAD_FROZEN:
-	case CPU_UP_CANCELED:
-	case CPU_UP_CANCELED_FROZEN:
-		unmap_cpu_from_node(lcpu);
-		ret = NOTIFY_OK;
-		break;
+	unmap_cpu_from_node(cpu);
 #endif
-	}
-	return ret;
+	return 0;
 }
 
 /*

@@ -913,11 +905,6 @@ static void __init

dump_numa_memory_topology(void) }
 }
 
-static struct notifier_block ppc64_numa_nb = {
-	.notifier_call = cpu_numa_callback,
-	.priority = 1 /* Must run before sched domains notifier. */
-};
-
 /* Initialize NODE_DATA for a node on the local memory */
 static void __init setup_node_data(int nid, u64 start_pfn, u64
end_pfn) {

@@ -953,7 +940,7 @@ static void __init setup_node_data(int nid, u64

start_pfn, u64 end_pfn) 
 void __init initmem_init(void)
 {
-	int nid, cpu;
+	int nid;
 
 	max_low_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
 	max_pfn = max_low_pfn;

@@ -985,15 +972,14 @@ void __init initmem_init(void)
 	setup_node_to_cpumask_map();
 
 	reset_numa_cpu_lookup_table();
-	register_cpu_notifier(&ppc64_numa_nb);
+
 	/*
 	 * We need the numa_cpu_lookup_table to be accurate for all

CPUs,
 	 * even before we online them, so that we can use
cpu_to_{node,mem}
 	 * early in boot, cf. smp_prepare_cpus().
 	 */
-	for_each_present_cpu(cpu) {
-		numa_setup_cpu((unsigned long)cpu);
-	}
+	cpuhp_setup_state(CPUHP_POWER_NUMA_PREPARE,
"POWER_NUMA_PREPARE",
+			  ppc_numa_cpu_prepare, ppc_numa_cpu_dead);
 }
 
 static int __init early_numa(char *p)

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 7449081..01133ec 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h

@@ -14,6 +14,7 @@ enum cpuhp_state {
 	CPUHP_PERF_SUPERH,
 	CPUHP_X86_HPET_DEAD,
 	CPUHP_WORKQUEUE_PREP,
+	CPUHP_POWER_NUMA_PREPARE,
 	CPUHP_NOTIFY_PREPARE,
 	CPUHP_BRINGUP_CPU,
 	CPUHP_AP_IDLE_DEAD,

Re: [patch V2 30/67] powerpc/numa: Convert to hotplug state machine

From: Anna-Maria Gleixner <anna-maria@linutronix.de>
Date: 2016-07-15 00:00:38

Hi,

On 2016-07-14 23:42, Anton Blanchard wrote:

Hi,

quoted

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

This is causing an oops on ppc64le QEMU, looks like a NULL pointer:

Did you tested it against tip WIP.hotplug?

Regards,
      Anna-Maria

Re: [patch V2 30/67] powerpc/numa: Convert to hotplug state machine

From: Anton Blanchard <hidden>
Date: 2016-07-15 00:28:50

Hi Anna-Maria,

quoted

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

This is causing an oops on ppc64le QEMU, looks like a NULL
pointer:

Did you tested it against tip WIP.hotplug?

I noticed tip started failing in my CI environment which tests on QEMU.
The failure bisected to commit 425209e0abaf2c6e3a90ce4fedb935c10652bf80

It reproduces running ppc64le QEMU on a x86-64 box. On Ubuntu:

sudo apt-get install qemu-system-ppc gcc-powerpc64le-linux-gnu

make ARCH=powerpc pseries_le_defconfig

make ARCH=powerpc CROSS_COMPILE=powerpc64le-linux-gnu- vmlinux -j4

qemu-system-ppc64 -nographic -vga none -kernel vmlinux 

Anton

Re: [patch V2 30/67] powerpc/numa: Convert to hotplug state machine

From: Ingo Molnar <mingo@kernel.org>
Date: 2016-07-15 08:43:32

* Anton Blanchard [off-list ref] wrote:

Hi Anna-Maria,

quoted

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

This is causing an oops on ppc64le QEMU, looks like a NULL
pointer:

Did you tested it against tip WIP.hotplug?

I noticed tip started failing in my CI environment which tests on QEMU.
The failure bisected to commit 425209e0abaf2c6e3a90ce4fedb935c10652bf80

That's very useful, thanks Anton!

I have removed this commit from the series for the time being, refactored the 
followup commits (there was one trivial conflict). We can re-try this patch when a 
fix is found.

Thanks,

	Ingo

Re: [patch V2 30/67] powerpc/numa: Convert to hotplug state machine

From: Anton Blanchard <hidden>
Date: 2016-07-15 12:14:56

quoted

I noticed tip started failing in my CI environment which tests on
QEMU. The failure bisected to commit
425209e0abaf2c6e3a90ce4fedb935c10652bf80

That's very useful, thanks Anton!

I have removed this commit from the series for the time being,
refactored the followup commits (there was one trivial conflict). We
can re-try this patch when a fix is found.

Thanks Ingo, my tests are passing again after your last push.

Anton

Re: [patch V2 30/67] powerpc/numa: Convert to hotplug state machine

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: 2016-07-15 16:20:57

* Anton Blanchard | 2016-07-15 10:28:25 [+1000]:

Hi Anna-Maria,

Hi Anton,

quoted

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs. =20

This is causing an oops on ppc64le QEMU, looks like a NULL
pointer: =20

=20
Did you tested it against tip WIP.hotplug?

I noticed tip started failing in my CI environment which tests on QEMU.
The failure bisected to commit 425209e0abaf2c6e3a90ce4fedb935c10652bf80

It reproduces running ppc64le QEMU on a x86-64 box. On Ubuntu:

=E2=80=A6

Thanks for that. I can reproduce this ontop of latest WIP.hotplug with
this patch.

Anton

Sebastian

[PATCH v2] powerpc/numa: Convert to hotplug state machine

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: 2016-07-18 14:08:10

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

v1=E2=80=A6v2: manual callback invocation on boot-CPU (cpuhp is not up yet =
and
       we need them all before additional CPUs are up).

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bharata B Rao <redacted>
Cc: Christophe Jaillet <redacted>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nikunj A Dadhania <redacted>
Cc: Paul Mackerras <redacted>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <redacted>
Cc: Thomas Gleixner <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 arch/powerpc/mm/numa.c     | 48 ++++++++++++++++++------------------------=
----
 include/linux/cpuhotplug.h |  1 +
 2 files changed, 20 insertions(+), 29 deletions(-)

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 669a15e7fa76..6dc07ddbfd04 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c

@@ -581,30 +581,22 @@ static void verify_cpu_node_mapping(int cpu, int node)
 	}
 }

=20
-static int cpu_numa_callback(struct notifier_block *nfb, unsigned long act=
ion,
-			     void *hcpu)
+/* Must run before sched domains notifier. */
+static int ppc_numa_cpu_prepare(unsigned int cpu)
 {
-	unsigned long lcpu =3D (unsigned long)hcpu;
-	int ret =3D NOTIFY_DONE, nid;
+	int nid;
=20
-	switch (action) {
-	case CPU_UP_PREPARE:
-	case CPU_UP_PREPARE_FROZEN:
-		nid =3D numa_setup_cpu(lcpu);
-		verify_cpu_node_mapping((int)lcpu, nid);
-		ret =3D NOTIFY_OK;
-		break;
+	nid =3D numa_setup_cpu(cpu);
+	verify_cpu_node_mapping(cpu, nid);
+	return 0;
+}
+
+static int ppc_numa_cpu_dead(unsigned int cpu)
+{
 #ifdef CONFIG_HOTPLUG_CPU
-	case CPU_DEAD:
-	case CPU_DEAD_FROZEN:
-	case CPU_UP_CANCELED:
-	case CPU_UP_CANCELED_FROZEN:
-		unmap_cpu_from_node(lcpu);
-		ret =3D NOTIFY_OK;
-		break;
+	unmap_cpu_from_node(cpu);
 #endif
-	}
-	return ret;
+	return 0;
 }
=20
 /*

@@ -913,11 +905,6 @@ static void __init dump_numa_memory_topology(void)
 	}
 }

=20
-static struct notifier_block ppc64_numa_nb =3D {
-	.notifier_call =3D cpu_numa_callback,
-	.priority =3D 1 /* Must run before sched domains notifier. */
-};
-
 /* Initialize NODE_DATA for a node on the local memory */
 static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
 {

@@ -985,15 +972,18 @@ void __init initmem_init(void)
 	setup_node_to_cpumask_map();

=20
 	reset_numa_cpu_lookup_table();
-	register_cpu_notifier(&ppc64_numa_nb);
+
 	/*
 	 * We need the numa_cpu_lookup_table to be accurate for all CPUs,
 	 * even before we online them, so that we can use cpu_to_{node,mem}
 	 * early in boot, cf. smp_prepare_cpus().
+	 * _nocalls() + manual invocation is used because cpuhp is not yet
+	 * initialized for the boot CPU.
 	 */
-	for_each_present_cpu(cpu) {
-		numa_setup_cpu((unsigned long)cpu);
-	}
+	cpuhp_setup_state_nocalls(CPUHP_POWER_NUMA_PREPARE, "POWER_NUMA_PREPARE",
+				  ppc_numa_cpu_prepare, ppc_numa_cpu_dead);
+	for_each_present_cpu(cpu)
+		numa_setup_cpu(cpu);
 }
=20
 static int __init early_numa(char *p)

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 09ef54bcba39..5015f463d314 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h

@@ -15,6 +15,7 @@ enum cpuhp_state {
 	CPUHP_X86_HPET_DEAD,
 	CPUHP_X86_APB_DEAD,
 	CPUHP_WORKQUEUE_PREP,
+	CPUHP_POWER_NUMA_PREPARE,
 	CPUHP_HRTIMERS_PREPARE,
 	CPUHP_PROFILE_PREPARE,
 	CPUHP_X2APIC_PREPARE,
--=20

2.8.1

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