* [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid of sparse context imbalance warning
@ 2015-06-02 19:57 Tolga Ceylan
2015-06-03 6:42 ` Sudip Mukherjee
0 siblings, 1 reply; 6+ messages in thread
From: Tolga Ceylan @ 2015-06-02 19:57 UTC (permalink / raw)
To: Oleg Drokin, Andreas Dilger, Greg Kroah-Hartman, Julia Lawall,
Greg Donald, Joe Perches, Darshana Padmadas, Arjun AK,
Tolga Ceylan, HPDD-discuss, devel, linux-kernel
In llog_cat_new_log(), sparse emits a context imbalance (unexpected lock)
warning due its inability to detect the noreturn attribute in
lbug_with_lock() function inside LBUG macro. Adding a never reached
return statement suppresses this warning.
Signed-off-by: Tolga Ceylan <tolga.ceylan@gmail.com>
---
drivers/staging/lustre/lustre/obdclass/llog_cat.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/staging/lustre/lustre/obdclass/llog_cat.c b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
index c8f6ab0..259947c 100644
--- a/drivers/staging/lustre/lustre/obdclass/llog_cat.c
+++ b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
@@ -108,6 +108,7 @@ static int llog_cat_new_log(const struct lu_env *env,
index);
spin_unlock(&loghandle->lgh_hdr_lock);
LBUG(); /* should never happen */
+ return -EINVAL;
}
spin_unlock(&loghandle->lgh_hdr_lock);
--
2.4.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid of sparse context imbalance warning
2015-06-02 19:57 [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid of sparse context imbalance warning Tolga Ceylan
@ 2015-06-03 6:42 ` Sudip Mukherjee
2015-06-03 15:47 ` Tolga Ceylan
0 siblings, 1 reply; 6+ messages in thread
From: Sudip Mukherjee @ 2015-06-03 6:42 UTC (permalink / raw)
To: Tolga Ceylan
Cc: Oleg Drokin, Andreas Dilger, Greg Kroah-Hartman, Julia Lawall,
Greg Donald, Joe Perches, Darshana Padmadas, Arjun AK,
HPDD-discuss, devel, linux-kernel
On Tue, Jun 02, 2015 at 12:57:20PM -0700, Tolga Ceylan wrote:
> In llog_cat_new_log(), sparse emits a context imbalance (unexpected lock)
> warning due its inability to detect the noreturn attribute in
> lbug_with_lock() function inside LBUG macro. Adding a never reached
> return statement suppresses this warning.
but adding a statement which never executes, is that the correct solution?
what about :
diff --git a/drivers/staging/lustre/lustre/obdclass/llog_cat.c b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
index c8f6ab0..1cb3495 100644
--- a/drivers/staging/lustre/lustre/obdclass/llog_cat.c
+++ b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
@@ -103,13 +103,12 @@ static int llog_cat_new_log(const struct lu_env *env,
spin_lock(&loghandle->lgh_hdr_lock);
llh->llh_count++;
- if (ext2_set_bit(index, llh->llh_bitmap)) {
- CERROR("argh, index %u already set in log bitmap?\n",
- index);
- spin_unlock(&loghandle->lgh_hdr_lock);
+ rc = ext2_set_bit(index, llh->llh_bitmap);
+ spin_unlock(&loghandle->lgh_hdr_lock);
+ if (rc) {
+ CERROR("argh, index %u already set in log bitmap?\n", index);
LBUG(); /* should never happen */
}
- spin_unlock(&loghandle->lgh_hdr_lock);
cathandle->lgh_last_idx = index;
llh->llh_tail.lrt_index = index;
regards
sudip
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid of sparse context imbalance warning
2015-06-03 6:42 ` Sudip Mukherjee
@ 2015-06-03 15:47 ` Tolga Ceylan
2015-06-03 16:36 ` Sudip Mukherjee
0 siblings, 1 reply; 6+ messages in thread
From: Tolga Ceylan @ 2015-06-03 15:47 UTC (permalink / raw)
To: Sudip Mukherjee
Cc: Oleg Drokin, Andreas Dilger, Greg Kroah-Hartman, Julia Lawall,
Greg Donald, Joe Perches, Darshana Padmadas, Arjun AK,
HPDD-discuss, devel, linux-kernel
The second patch is better (it also keeps the lock locked shorter.) Do
I need to resend?
On Tue, Jun 2, 2015 at 11:42 PM, Sudip Mukherjee
<sudipm.mukherjee@gmail.com> wrote:
> On Tue, Jun 02, 2015 at 12:57:20PM -0700, Tolga Ceylan wrote:
>> In llog_cat_new_log(), sparse emits a context imbalance (unexpected lock)
>> warning due its inability to detect the noreturn attribute in
>> lbug_with_lock() function inside LBUG macro. Adding a never reached
>> return statement suppresses this warning.
> but adding a statement which never executes, is that the correct solution?
> what about :
>
> diff --git a/drivers/staging/lustre/lustre/obdclass/llog_cat.c b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
> index c8f6ab0..1cb3495 100644
> --- a/drivers/staging/lustre/lustre/obdclass/llog_cat.c
> +++ b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
> @@ -103,13 +103,12 @@ static int llog_cat_new_log(const struct lu_env *env,
>
> spin_lock(&loghandle->lgh_hdr_lock);
> llh->llh_count++;
> - if (ext2_set_bit(index, llh->llh_bitmap)) {
> - CERROR("argh, index %u already set in log bitmap?\n",
> - index);
> - spin_unlock(&loghandle->lgh_hdr_lock);
> + rc = ext2_set_bit(index, llh->llh_bitmap);
> + spin_unlock(&loghandle->lgh_hdr_lock);
> + if (rc) {
> + CERROR("argh, index %u already set in log bitmap?\n", index);
> LBUG(); /* should never happen */
> }
> - spin_unlock(&loghandle->lgh_hdr_lock);
>
> cathandle->lgh_last_idx = index;
> llh->llh_tail.lrt_index = index;
>
>
> regards
> sudip
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid of sparse context imbalance warning
2015-06-03 15:47 ` Tolga Ceylan
@ 2015-06-03 16:36 ` Sudip Mukherjee
0 siblings, 0 replies; 6+ messages in thread
From: Sudip Mukherjee @ 2015-06-03 16:36 UTC (permalink / raw)
To: Tolga Ceylan
Cc: Oleg Drokin, Andreas Dilger, Greg Kroah-Hartman, Julia Lawall,
Greg Donald, Joe Perches, Darshana Padmadas, Arjun AK,
HPDD-discuss, devel, linux-kernel
On Wed, Jun 03, 2015 at 08:47:38AM -0700, Tolga Ceylan wrote:
> The second patch is better (it also keeps the lock locked shorter.) Do
> I need to resend?
yes, please, it was not formally submitted.
regards
sudip
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid of sparse context imbalance warning
2015-06-03 20:20 Tolga Ceylan
@ 2015-06-08 19:35 ` Greg Kroah-Hartman
0 siblings, 0 replies; 6+ messages in thread
From: Greg Kroah-Hartman @ 2015-06-08 19:35 UTC (permalink / raw)
To: Tolga Ceylan
Cc: Oleg Drokin, Andreas Dilger, Julia Lawall, Arjun AK, Greg Donald,
Darshana Padmadas, Joe Perches, HPDD-discuss, devel,
linux-kernel
On Wed, Jun 03, 2015 at 01:20:10PM -0700, Tolga Ceylan wrote:
> In llog_cat_new_log(), sparse emits a context imbalance (unexpected lock)
> warning due its inability to detect the noreturn attribute in
> lbug_with_lock() function inside LBUG macro. With this patch, we unlock
> the spinlock before checking the error condition to resolve this warning.
That's a bug in sparse, not in the code, please don't work around tool
bugs by changing kernel code.
thanks,
greg k-h
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid of sparse context imbalance warning
@ 2015-06-03 20:20 Tolga Ceylan
2015-06-08 19:35 ` Greg Kroah-Hartman
0 siblings, 1 reply; 6+ messages in thread
From: Tolga Ceylan @ 2015-06-03 20:20 UTC (permalink / raw)
To: Oleg Drokin, Andreas Dilger, Greg Kroah-Hartman, Julia Lawall,
Arjun AK, Greg Donald, Darshana Padmadas, Tolga Ceylan,
Joe Perches, HPDD-discuss, devel, linux-kernel
In llog_cat_new_log(), sparse emits a context imbalance (unexpected lock)
warning due its inability to detect the noreturn attribute in
lbug_with_lock() function inside LBUG macro. With this patch, we unlock
the spinlock before checking the error condition to resolve this warning.
Signed-off-by: Tolga Ceylan <tolga.ceylan@gmail.com>
---
drivers/staging/lustre/lustre/obdclass/llog_cat.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/staging/lustre/lustre/obdclass/llog_cat.c b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
index c8f6ab0..280e861 100644
--- a/drivers/staging/lustre/lustre/obdclass/llog_cat.c
+++ b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
@@ -103,13 +103,13 @@ static int llog_cat_new_log(const struct lu_env *env,
spin_lock(&loghandle->lgh_hdr_lock);
llh->llh_count++;
- if (ext2_set_bit(index, llh->llh_bitmap)) {
+ rc = ext2_set_bit(index, llh->llh_bitmap);
+ spin_unlock(&loghandle->lgh_hdr_lock);
+ if (rc) {
CERROR("argh, index %u already set in log bitmap?\n",
index);
- spin_unlock(&loghandle->lgh_hdr_lock);
LBUG(); /* should never happen */
}
- spin_unlock(&loghandle->lgh_hdr_lock);
cathandle->lgh_last_idx = index;
llh->llh_tail.lrt_index = index;
--
2.4.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2015-06-08 19:35 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-06-02 19:57 [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid of sparse context imbalance warning Tolga Ceylan
2015-06-03 6:42 ` Sudip Mukherjee
2015-06-03 15:47 ` Tolga Ceylan
2015-06-03 16:36 ` Sudip Mukherjee
2015-06-03 20:20 Tolga Ceylan
2015-06-08 19:35 ` Greg Kroah-Hartman
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