* [PATCH] powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
@ 2017-08-11 20:05 ` Dan Carpenter
0 siblings, 0 replies; 10+ messages in thread
From: Dan Carpenter @ 2017-08-11 20:05 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Anju T Sudhakar
Cc: Paul Mackerras, Michael Ellerman, Madhavan Srinivasan,
Hemant Kumar, linuxppc-dev, kernel-janitors
There is a typo so we call unlock instead of lock.
Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
I also don't understand how the &nest_imc_refc[node_id].lock works. Why
can't we use ref->lock everywhere? They seem equivalent, and my static
checker complains if we call the same lock different names.
diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
index 46cd912af060..52017f6eafd9 100644
--- a/arch/powerpc/perf/imc-pmu.c
+++ b/arch/powerpc/perf/imc-pmu.c
@@ -1124,7 +1124,7 @@ static void cleanup_all_thread_imc_memory(void)
static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
{
if (pmu_ptr->domain == IMC_DOMAIN_NEST) {
- mutex_unlock(&nest_init_lock);
+ mutex_lock(&nest_init_lock);
if (nest_pmus == 1) {
cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE);
kfree(nest_imc_refc);
^ permalink raw reply related [flat|nested] 10+ messages in thread* Re: [PATCH] powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
2017-08-11 20:05 ` Dan Carpenter
@ 2017-08-14 3:30 ` Michael Ellerman
-1 siblings, 0 replies; 10+ messages in thread
From: Michael Ellerman @ 2017-08-14 3:30 UTC (permalink / raw)
To: Dan Carpenter, Benjamin Herrenschmidt, Anju T Sudhakar
Cc: Paul Mackerras, Madhavan Srinivasan, Hemant Kumar, linuxppc-dev,
kernel-janitors
Dan Carpenter <dan.carpenter@oracle.com> writes:
> There is a typo so we call unlock instead of lock.
>
> Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> I also don't understand how the &nest_imc_refc[node_id].lock works. Why
> can't we use ref->lock everywhere? They seem equivalent, and my static
> checker complains if we call the same lock different names.
That looks like a bug to me, ie. we should always use ref.
Maddy?
cheers
> diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
> index 46cd912af060..52017f6eafd9 100644
> --- a/arch/powerpc/perf/imc-pmu.c
> +++ b/arch/powerpc/perf/imc-pmu.c
> @@ -1124,7 +1124,7 @@ static void cleanup_all_thread_imc_memory(void)
> static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
> {
> if (pmu_ptr->domain = IMC_DOMAIN_NEST) {
> - mutex_unlock(&nest_init_lock);
> + mutex_lock(&nest_init_lock);
> if (nest_pmus = 1) {
> cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE);
> kfree(nest_imc_refc);
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH] powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
@ 2017-08-14 3:30 ` Michael Ellerman
0 siblings, 0 replies; 10+ messages in thread
From: Michael Ellerman @ 2017-08-14 3:30 UTC (permalink / raw)
To: Dan Carpenter, Benjamin Herrenschmidt, Anju T Sudhakar
Cc: Paul Mackerras, Madhavan Srinivasan, Hemant Kumar, linuxppc-dev,
kernel-janitors
Dan Carpenter <dan.carpenter@oracle.com> writes:
> There is a typo so we call unlock instead of lock.
>
> Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> I also don't understand how the &nest_imc_refc[node_id].lock works. Why
> can't we use ref->lock everywhere? They seem equivalent, and my static
> checker complains if we call the same lock different names.
That looks like a bug to me, ie. we should always use ref.
Maddy?
cheers
> diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
> index 46cd912af060..52017f6eafd9 100644
> --- a/arch/powerpc/perf/imc-pmu.c
> +++ b/arch/powerpc/perf/imc-pmu.c
> @@ -1124,7 +1124,7 @@ static void cleanup_all_thread_imc_memory(void)
> static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
> {
> if (pmu_ptr->domain == IMC_DOMAIN_NEST) {
> - mutex_unlock(&nest_init_lock);
> + mutex_lock(&nest_init_lock);
> if (nest_pmus == 1) {
> cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE);
> kfree(nest_imc_refc);
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH] powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
2017-08-14 3:30 ` Michael Ellerman
@ 2017-08-14 4:12 ` Madhavan Srinivasan
-1 siblings, 0 replies; 10+ messages in thread
From: Madhavan Srinivasan @ 2017-08-14 4:00 UTC (permalink / raw)
To: Michael Ellerman, Dan Carpenter, Benjamin Herrenschmidt,
Anju T Sudhakar
Cc: Paul Mackerras, Hemant Kumar, linuxppc-dev, kernel-janitors
On Monday 14 August 2017 09:00 AM, Michael Ellerman wrote:
> Dan Carpenter <dan.carpenter@oracle.com> writes:
>
>> There is a typo so we call unlock instead of lock.
>>
>> Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
>> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
>> ---
>> I also don't understand how the &nest_imc_refc[node_id].lock works. Why
>> can't we use ref->lock everywhere? They seem equivalent, and my static
>> checker complains if we call the same lock different names.
> That looks like a bug to me, ie. we should always use ref.
ok. will send a fix.
Thanks
Maddy
>
> Maddy?
>
> cheers
>
>> diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
>> index 46cd912af060..52017f6eafd9 100644
>> --- a/arch/powerpc/perf/imc-pmu.c
>> +++ b/arch/powerpc/perf/imc-pmu.c
>> @@ -1124,7 +1124,7 @@ static void cleanup_all_thread_imc_memory(void)
>> static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
>> {
>> if (pmu_ptr->domain == IMC_DOMAIN_NEST) {
>> - mutex_unlock(&nest_init_lock);
>> + mutex_lock(&nest_init_lock);
>> if (nest_pmus == 1) {
>> cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE);
>> kfree(nest_imc_refc);
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH] powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
@ 2017-08-14 4:12 ` Madhavan Srinivasan
0 siblings, 0 replies; 10+ messages in thread
From: Madhavan Srinivasan @ 2017-08-14 4:12 UTC (permalink / raw)
To: Michael Ellerman, Dan Carpenter, Benjamin Herrenschmidt,
Anju T Sudhakar
Cc: Paul Mackerras, Hemant Kumar, linuxppc-dev, kernel-janitors
On Monday 14 August 2017 09:00 AM, Michael Ellerman wrote:
> Dan Carpenter <dan.carpenter@oracle.com> writes:
>
>> There is a typo so we call unlock instead of lock.
>>
>> Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
>> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
>> ---
>> I also don't understand how the &nest_imc_refc[node_id].lock works. Why
>> can't we use ref->lock everywhere? They seem equivalent, and my static
>> checker complains if we call the same lock different names.
> That looks like a bug to me, ie. we should always use ref.
ok. will send a fix.
Thanks
Maddy
>
> Maddy?
>
> cheers
>
>> diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
>> index 46cd912af060..52017f6eafd9 100644
>> --- a/arch/powerpc/perf/imc-pmu.c
>> +++ b/arch/powerpc/perf/imc-pmu.c
>> @@ -1124,7 +1124,7 @@ static void cleanup_all_thread_imc_memory(void)
>> static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
>> {
>> if (pmu_ptr->domain = IMC_DOMAIN_NEST) {
>> - mutex_unlock(&nest_init_lock);
>> + mutex_lock(&nest_init_lock);
>> if (nest_pmus = 1) {
>> cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE);
>> kfree(nest_imc_refc);
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
2017-08-11 20:05 ` Dan Carpenter
@ 2017-08-14 3:59 ` Madhavan Srinivasan
-1 siblings, 0 replies; 10+ messages in thread
From: Madhavan Srinivasan @ 2017-08-14 3:58 UTC (permalink / raw)
To: Dan Carpenter, Benjamin Herrenschmidt, Anju T Sudhakar
Cc: Paul Mackerras, Michael Ellerman, Hemant Kumar, linuxppc-dev,
kernel-janitors
On Saturday 12 August 2017 01:35 AM, Dan Carpenter wrote:
> There is a typo so we call unlock instead of lock.
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
nest_imc_refc used to maintain list of perf sessions thats using the
nest units currently. This is needed in turning off nest engine microcode
when not in use.
Yes will send a patch to fix ref->lock change.
Thanks for fix
Maddy
>
> Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> I also don't understand how the &nest_imc_refc[node_id].lock works. Why
> can't we use ref->lock everywhere? They seem equivalent, and my static
> checker complains if we call the same lock different names.
>
> diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
> index 46cd912af060..52017f6eafd9 100644
> --- a/arch/powerpc/perf/imc-pmu.c
> +++ b/arch/powerpc/perf/imc-pmu.c
> @@ -1124,7 +1124,7 @@ static void cleanup_all_thread_imc_memory(void)
> static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
> {
> if (pmu_ptr->domain == IMC_DOMAIN_NEST) {
> - mutex_unlock(&nest_init_lock);
> + mutex_lock(&nest_init_lock);
> if (nest_pmus == 1) {
> cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE);
> kfree(nest_imc_refc);
>
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH] powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
@ 2017-08-14 3:59 ` Madhavan Srinivasan
0 siblings, 0 replies; 10+ messages in thread
From: Madhavan Srinivasan @ 2017-08-14 3:59 UTC (permalink / raw)
To: Dan Carpenter, Benjamin Herrenschmidt, Anju T Sudhakar
Cc: Paul Mackerras, Michael Ellerman, Hemant Kumar, linuxppc-dev,
kernel-janitors
On Saturday 12 August 2017 01:35 AM, Dan Carpenter wrote:
> There is a typo so we call unlock instead of lock.
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
nest_imc_refc used to maintain list of perf sessions thats using the
nest units currently. This is needed in turning off nest engine microcode
when not in use.
Yes will send a patch to fix ref->lock change.
Thanks for fix
Maddy
>
> Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> I also don't understand how the &nest_imc_refc[node_id].lock works. Why
> can't we use ref->lock everywhere? They seem equivalent, and my static
> checker complains if we call the same lock different names.
>
> diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
> index 46cd912af060..52017f6eafd9 100644
> --- a/arch/powerpc/perf/imc-pmu.c
> +++ b/arch/powerpc/perf/imc-pmu.c
> @@ -1124,7 +1124,7 @@ static void cleanup_all_thread_imc_memory(void)
> static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
> {
> if (pmu_ptr->domain = IMC_DOMAIN_NEST) {
> - mutex_unlock(&nest_init_lock);
> + mutex_lock(&nest_init_lock);
> if (nest_pmus = 1) {
> cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE);
> kfree(nest_imc_refc);
>
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
2017-08-11 20:05 ` Dan Carpenter
@ 2017-08-16 12:29 ` Michael Ellerman
-1 siblings, 0 replies; 10+ messages in thread
From: Michael Ellerman @ 2017-08-16 12:29 UTC (permalink / raw)
To: Dan Carpenter, Benjamin Herrenschmidt, Anju T Sudhakar
Cc: Madhavan Srinivasan, kernel-janitors, linuxppc-dev,
Paul Mackerras, Hemant Kumar
On Fri, 2017-08-11 at 20:05:41 UTC, Dan Carpenter wrote:
> There is a typo so we call unlock instead of lock.
>
> Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/b3376dcc6c62452fe24e76d8fc35bb
cheers
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: powerpc/perf: double unlock bug in imc_common_cpuhp_mem_free()
@ 2017-08-16 12:29 ` Michael Ellerman
0 siblings, 0 replies; 10+ messages in thread
From: Michael Ellerman @ 2017-08-16 12:29 UTC (permalink / raw)
To: Dan Carpenter, Benjamin Herrenschmidt, Anju T Sudhakar
Cc: Madhavan Srinivasan, kernel-janitors, linuxppc-dev,
Paul Mackerras, Hemant Kumar
On Fri, 2017-08-11 at 20:05:41 UTC, Dan Carpenter wrote:
> There is a typo so we call unlock instead of lock.
>
> Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/b3376dcc6c62452fe24e76d8fc35bb
cheers
^ permalink raw reply [flat|nested] 10+ messages in thread