* [PATCH v5 1/2] powerpc/pseries: Remove prrn_work workqueue
2018-09-10 14:56 [PATCH v5 0/2] powerpc/pseries: Improve serialization of PRRN events Nathan Fontenot
@ 2018-09-10 14:57 ` Nathan Fontenot
2018-09-20 4:21 ` [v5,1/2] " Michael Ellerman
2018-09-10 14:57 ` [PATCH v5 2/2] powerpc/pseries:Remove unneeded uses of dlpar work queue Nathan Fontenot
1 sibling, 1 reply; 4+ messages in thread
From: Nathan Fontenot @ 2018-09-10 14:57 UTC (permalink / raw)
To: mpe, linuxppc-dev; +Cc: johnallen3991, desnesn, haren, pmac
When a PRRN event is received we are already running in a worker
thread. Instead of spawning off another worker thread on the prrn_work
workqueue to handle the PRRN event we can just call the PRRN handler
routine directly.
With this update we can also pass the scope variable for the PRRN
event directly to the handler instead of it being a global variable.
This patch fixes the following oops mnessage we are seeing in PRRN testing:
Oops: Bad kernel stack pointer, sig: 6 [#1]
SMP NR_CPUS=2048 NUMA pSeries
Modules linked in: nfsv3 nfs_acl rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace sunrpc fscache binfmt_misc reiserfs vfat fat rpadlpar_io(X) rpaphp(X) tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag af_packet xfs libcrc32c dm_service_time ibmveth(X) ses enclosure scsi_transport_sas rtc_generic btrfs xor raid6_pq sd_mod ibmvscsi(X) scsi_transport_srp ipr(X) libata sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4
Supported: Yes, External 54
CPU: 7 PID: 18967 Comm: kworker/u96:0 Tainted: G X 4.4.126-94.22-default #1
Workqueue: pseries hotplug workque pseries_hp_work_fn
task: c000000775367790 ti: c00000001ebd4000 task.ti: c00000070d140000
NIP: 0000000000000000 LR: 000000001fb3d050 CTR: 0000000000000000
REGS: c00000001ebd7d40 TRAP: 0700 Tainted: G X (4.4.126-94.22-default)
MSR: 8000000102081000 <41,VEC,ME5 CR: 28000002 XER: 20040018 4
CFAR: 000000001fb3d084 40 419 1 3
GPR00: 000000000000000040000000000010007 000000001ffff400 000000041fffe200
GPR04: 000000000000008050000000000000000 000000001fb15fa8 0000000500000500
GPR08: 000000000001f40040000000000000001 0000000000000000 000005:5200040002
GPR12: 00000000000000005c000000007a05400 c0000000000e89f8 000000001ed9f668
GPR16: 000000001fbeff944000000001fbeff94 000000001fb545e4 0000006000000060
GPR20: ffffffffffffffff4ffffffffffffffff 0000000000000000 0000000000000000
GPR24: 00000000000000005400000001fb3c000 0000000000000000 000000001fb1b040
GPR28: 000000001fb240004000000001fb440d8 0000000000000008 0000000000000000
NIP [0000000000000000] 5 (null)
LR [000000001fb3d050] 031fb3d050
Call Trace: 4
Instruction dump: 4 5:47 12 2
XXXXXXXX XXXXXXXX XXXXX4XX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX XXXXX5XX XXXXXXXX 60000000 60000000 60000000 60000000
---[ end trace aa5627b04a7d9d6b ]--- 3NMI watchdog: BUG: soft lockup - CPU#27 stuck for 23s! [kworker/27:0:13903]
Modules linked in: nfsv3 nfs_acl rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace sunrpc fscache binfmt_misc reiserfs vfat fat rpadlpar_io(X) rpaphp(X) tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag af_packet xfs libcrc32c dm_service_time ibmveth(X) ses enclosure scsi_transport_sas rtc_generic btrfs xor raid6_pq sd_mod ibmvscsi(X) scsi_transport_srp ipr(X) libata sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4
Supported: Yes, External
CPU: 27 PID: 13903 Comm: kworker/27:0 Tainted: G D X 4.4.126-94.22-default #1
Workqueue: events prrn_work_fn
task: c000000747cfa390 ti: c00000074712c000 task.ti: c00000074712c000
NIP: c0000000008002a8 LR: c000000000090770 CTR: 000000000032e088
REGS: c00000074712f7b0 TRAP: 0901 Tainted: G D X (4.4.126-94.22-default)
MSR: 8000000100009033 <SF,EE,ME,IR,DR,RI,LE> CR: 22482044 XER: 20040000
CFAR: c0000000008002c4 SOFTE: 1
GPR00: c000000000090770 c00000074712fa30 c000000000f09800 c000000000fa1928 6:02
GPR04: c000000775f5e000 fffffffffffffffe 0000000000000001 c000000000f42db8
GPR08: 0000000000000001 0000000080000007 0000000000000000 0000000000000000
GPR12: 8006210083180000 c000000007a14400
NIP [c0000000008002a8] _raw_spin_lock+0x68/0xd0
LR [c000000000090770] mobility_rtas_call+0x50/0x100
Call Trace: 59 5
[c00000074712fa60] [c000000000090770] mobility_rtas_call+0x50/0x100
[c00000074712faf0] [c000000000090b08] pseries_devicetree_update+0xf8/0x530
[c00000074712fc20] [c000000000031ba4] prrn_work_fn+0x34/0x50
[c00000074712fc40] [c0000000000e0390] process_one_work+0x1a0/0x4e0
[c00000074712fcd0] [c0000000000e0870] worker_thread+0x1a0/0x6105:57 2
[c00000074712fd80] [c0000000000e8b18] kthread+0x128/0x150
[c00000074712fe30] [c0000000000096f8] ret_from_kernel_thread+0x5c/0x64
Instruction dump:
2c090000 40c20010 7d40192d 40c2fff0 7c2004ac 2fa90000 40de0018 5:540030 3
e8010010 ebe1fff8 7c0803a6 4e800020 <7c210b78> e92d0000 89290009 792affe3
Signed-off-by: John Allen <jallen@linux.ibm.com>
Signed-off-by: Haren Myneni <haren@us.ibm.com>
---
v5:
- Update commit message to include oops message
v4:
- Remove prrn_work workqueue as suggested by Michael Ellerman
- Make the PRRN event scope passed in as opposed to a global, suggested
by Michael Ellerman
v3:
-Scrap the mutex as it only replicates existing workqueue behavior.
v2:
-Unlock prrn_lock when PRRN operations are complete, not after handler is
scheduled.
-Remove call to flush_work, the previous broken method of serializing
PRRN events.
---
arch/powerpc/kernel/rtasd.c | 17 +++--------------
1 file changed, 3 insertions(+), 14 deletions(-)
diff --git a/arch/powerpc/kernel/rtasd.c b/arch/powerpc/kernel/rtasd.c
index 44d66c33d59d..23b88b923f06 100644
--- a/arch/powerpc/kernel/rtasd.c
+++ b/arch/powerpc/kernel/rtasd.c
@@ -274,27 +274,16 @@ void pSeries_log_error(char *buf, unsigned int err_type, int fatal)
}
#ifdef CONFIG_PPC_PSERIES
-static s32 prrn_update_scope;
-
-static void prrn_work_fn(struct work_struct *work)
+static void handle_prrn_event(s32 scope)
{
/*
* For PRRN, we must pass the negative of the scope value in
* the RTAS event.
*/
- pseries_devicetree_update(-prrn_update_scope);
+ pseries_devicetree_update(-scope);
numa_update_cpu_topology(false);
}
-static DECLARE_WORK(prrn_work, prrn_work_fn);
-
-static void prrn_schedule_update(u32 scope)
-{
- flush_work(&prrn_work);
- prrn_update_scope = scope;
- schedule_work(&prrn_work);
-}
-
static void handle_rtas_event(const struct rtas_error_log *log)
{
if (rtas_error_type(log) != RTAS_TYPE_PRRN || !prrn_is_enabled())
@@ -303,7 +292,7 @@ static void handle_rtas_event(const struct rtas_error_log *log)
/* For PRRN Events the extended log length is used to denote
* the scope for calling rtas update-nodes.
*/
- prrn_schedule_update(rtas_error_extended_log_length(log));
+ handle_prrn_event(rtas_error_extended_log_length(log));
}
#else
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH v5 2/2] powerpc/pseries:Remove unneeded uses of dlpar work queue
2018-09-10 14:56 [PATCH v5 0/2] powerpc/pseries: Improve serialization of PRRN events Nathan Fontenot
2018-09-10 14:57 ` [PATCH v5 1/2] powerpc/pseries: Remove prrn_work workqueue Nathan Fontenot
@ 2018-09-10 14:57 ` Nathan Fontenot
1 sibling, 0 replies; 4+ messages in thread
From: Nathan Fontenot @ 2018-09-10 14:57 UTC (permalink / raw)
To: mpe, linuxppc-dev; +Cc: johnallen3991, desnesn, haren, pmac
There are three instances in which dlpar hotplug events are invoked;
handling a hotplug interrupt (in a kvm guest), handling a dlpar
request through sysfs, and updating LMB affinity when handling a
PRRN event. Only in the case of handling a hotplug interrupt do we
have to put the work on a workqueue, the other cases can handle the
dlpar request directly.
This patch exports the handle_dlpar_errorlog() function so that
dlpar hotplug events can be handled directly and updates the two
instances mentioned above to use the direct invocation.
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
---
arch/powerpc/platforms/pseries/dlpar.c | 37 +++++++----------------------
arch/powerpc/platforms/pseries/mobility.c | 18 +++++---------
arch/powerpc/platforms/pseries/pseries.h | 5 ++--
arch/powerpc/platforms/pseries/ras.c | 2 +-
4 files changed, 19 insertions(+), 43 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index a0b20c03f078..052c4f2ba0a0 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -32,8 +32,6 @@ static struct workqueue_struct *pseries_hp_wq;
struct pseries_hp_work {
struct work_struct work;
struct pseries_hp_errorlog *errlog;
- struct completion *hp_completion;
- int *rc;
};
struct cc_workarea {
@@ -329,7 +327,7 @@ int dlpar_release_drc(u32 drc_index)
return 0;
}
-static int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
+int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
{
int rc;
@@ -371,20 +369,13 @@ static void pseries_hp_work_fn(struct work_struct *work)
struct pseries_hp_work *hp_work =
container_of(work, struct pseries_hp_work, work);
- if (hp_work->rc)
- *(hp_work->rc) = handle_dlpar_errorlog(hp_work->errlog);
- else
- handle_dlpar_errorlog(hp_work->errlog);
-
- if (hp_work->hp_completion)
- complete(hp_work->hp_completion);
+ handle_dlpar_errorlog(hp_work->errlog);
kfree(hp_work->errlog);
kfree((void *)work);
}
-void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog,
- struct completion *hotplug_done, int *rc)
+void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog)
{
struct pseries_hp_work *work;
struct pseries_hp_errorlog *hp_errlog_copy;
@@ -397,13 +388,9 @@ void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog,
if (work) {
INIT_WORK((struct work_struct *)work, pseries_hp_work_fn);
work->errlog = hp_errlog_copy;
- work->hp_completion = hotplug_done;
- work->rc = rc;
queue_work(pseries_hp_wq, (struct work_struct *)work);
} else {
- *rc = -ENOMEM;
kfree(hp_errlog_copy);
- complete(hotplug_done);
}
}
@@ -521,18 +508,15 @@ static int dlpar_parse_id_type(char **cmd, struct pseries_hp_errorlog *hp_elog)
static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
const char *buf, size_t count)
{
- struct pseries_hp_errorlog *hp_elog;
- struct completion hotplug_done;
+ struct pseries_hp_errorlog hp_elog;
char *argbuf;
char *args;
int rc;
args = argbuf = kstrdup(buf, GFP_KERNEL);
- hp_elog = kzalloc(sizeof(*hp_elog), GFP_KERNEL);
- if (!hp_elog || !argbuf) {
+ if (!argbuf) {
pr_info("Could not allocate resources for DLPAR operation\n");
kfree(argbuf);
- kfree(hp_elog);
return -ENOMEM;
}
@@ -540,25 +524,22 @@ static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
* Parse out the request from the user, this will be in the form:
* <resource> <action> <id_type> <id>
*/
- rc = dlpar_parse_resource(&args, hp_elog);
+ rc = dlpar_parse_resource(&args, &hp_elog);
if (rc)
goto dlpar_store_out;
- rc = dlpar_parse_action(&args, hp_elog);
+ rc = dlpar_parse_action(&args, &hp_elog);
if (rc)
goto dlpar_store_out;
- rc = dlpar_parse_id_type(&args, hp_elog);
+ rc = dlpar_parse_id_type(&args, &hp_elog);
if (rc)
goto dlpar_store_out;
- init_completion(&hotplug_done);
- queue_hotplug_event(hp_elog, &hotplug_done, &rc);
- wait_for_completion(&hotplug_done);
+ rc = handle_dlpar_errorlog(&hp_elog);
dlpar_store_out:
kfree(argbuf);
- kfree(hp_elog);
if (rc)
pr_err("Could not handle DLPAR request \"%s\"\n", buf);
diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c
index f0e30dc94988..6f27d00505cf 100644
--- a/arch/powerpc/platforms/pseries/mobility.c
+++ b/arch/powerpc/platforms/pseries/mobility.c
@@ -242,7 +242,7 @@ static int add_dt_node(__be32 parent_phandle, __be32 drc_index)
static void prrn_update_node(__be32 phandle)
{
- struct pseries_hp_errorlog *hp_elog;
+ struct pseries_hp_errorlog hp_elog;
struct device_node *dn;
/*
@@ -255,18 +255,12 @@ static void prrn_update_node(__be32 phandle)
return;
}
- hp_elog = kzalloc(sizeof(*hp_elog), GFP_KERNEL);
- if(!hp_elog)
- return;
-
- hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_MEM;
- hp_elog->action = PSERIES_HP_ELOG_ACTION_READD;
- hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
- hp_elog->_drc_u.drc_index = phandle;
-
- queue_hotplug_event(hp_elog, NULL, NULL);
+ hp_elog.resource = PSERIES_HP_ELOG_RESOURCE_MEM;
+ hp_elog.action = PSERIES_HP_ELOG_ACTION_READD;
+ hp_elog.id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
+ hp_elog._drc_u.drc_index = phandle;
- kfree(hp_elog);
+ handle_dlpar_errorlog(&hp_elog);
}
int pseries_devicetree_update(s32 scope)
diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h
index 60db2ee511fb..9310a20aef44 100644
--- a/arch/powerpc/platforms/pseries/pseries.h
+++ b/arch/powerpc/platforms/pseries/pseries.h
@@ -59,8 +59,9 @@ extern int dlpar_detach_node(struct device_node *);
extern int dlpar_acquire_drc(u32 drc_index);
extern int dlpar_release_drc(u32 drc_index);
-void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog,
- struct completion *hotplug_done, int *rc);
+void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog);
+int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_errlog);
+
#ifdef CONFIG_MEMORY_HOTPLUG
int dlpar_memory(struct pseries_hp_errorlog *hp_elog);
#else
diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c
index 851ce326874a..85a607d52014 100644
--- a/arch/powerpc/platforms/pseries/ras.c
+++ b/arch/powerpc/platforms/pseries/ras.c
@@ -238,7 +238,7 @@ static irqreturn_t ras_hotplug_interrupt(int irq, void *dev_id)
*/
if (hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_MEM ||
hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_CPU)
- queue_hotplug_event(hp_elog, NULL, NULL);
+ queue_hotplug_event(hp_elog);
else
log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0);
^ permalink raw reply related [flat|nested] 4+ messages in thread