[06/13] libfrog: add missing per-thread variable error handling
diff mbox series

Message ID 156944723982.297677.3080857602921528738.stgit@magnolia
State New
Headers show
Series
  • libfrog/xfs_scrub: fix error handling
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Commit Message

Darrick J. Wong Sept. 25, 2019, 9:33 p.m. UTC
From: Darrick J. Wong <darrick.wong@oracle.com>

Add missing return value checks for everything that the per-thread
variable code calls.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 libfrog/ptvar.c |   17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

Comments

Eric Sandeen Oct. 9, 2019, 9:16 p.m. UTC | #1
On 9/25/19 4:33 PM, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> Add missing return value checks for everything that the per-thread
> variable code calls.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> ---
>  libfrog/ptvar.c |   17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)
> 
> 
> diff --git a/libfrog/ptvar.c b/libfrog/ptvar.c
> index 6cb58208..55324b71 100644
> --- a/libfrog/ptvar.c
> +++ b/libfrog/ptvar.c
> @@ -44,8 +44,12 @@ ptvar_alloc(
>  	int		ret;
>  
>  #ifdef _SC_LEVEL1_DCACHE_LINESIZE
> +	long		l1_dcache;
> +
>  	/* Try to prevent cache pingpong by aligning to cacheline size. */
> -	size = max(size, sysconf(_SC_LEVEL1_DCACHE_LINESIZE));
> +	l1_dcache = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
> +	if (l1_dcache > 0)
> +		size = roundup(size, l1_dcache);
>  #endif
>  
>  	ptv = malloc(PTVAR_SIZE(nr, size));
> @@ -88,17 +92,26 @@ ptvar_get(
>  	int		*retp)
>  {
>  	void		*p;
> +	int		ret;
>  
>  	p = pthread_getspecific(ptv->key);
>  	if (!p) {
>  		pthread_mutex_lock(&ptv->lock);
>  		assert(ptv->nr_used < ptv->nr_counters);
>  		p = &ptv->data[(ptv->nr_used++) * ptv->data_size];
> -		pthread_setspecific(ptv->key, p);
> +		ret = pthread_setspecific(ptv->key, p);
> +		if (ret)
> +			goto out_unlock;
>  		pthread_mutex_unlock(&ptv->lock);
>  	}
>  	*retp = 0;
>  	return p;
> +
> +out_unlock:
> +	ptv->nr_used--;
> +	pthread_mutex_unlock(&ptv->lock);
> +	*retp = ret;
> +	return NULL;

As of this patch I'm a little confused by the "error handling" in ptcounter_add():

        p = ptvar_get(ptc->var, &ret);
        assert(ret == 0);

?
Eric Sandeen Oct. 9, 2019, 9:40 p.m. UTC | #2
On 9/25/19 4:33 PM, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> Add missing return value checks for everything that the per-thread
> variable code calls.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

my question about handling in the caller got addressed by patch 9,
good enough.

Reviewed-by: Eric Sandeen <sandeen@redhat.com

Patch
diff mbox series

diff --git a/libfrog/ptvar.c b/libfrog/ptvar.c
index 6cb58208..55324b71 100644
--- a/libfrog/ptvar.c
+++ b/libfrog/ptvar.c
@@ -44,8 +44,12 @@  ptvar_alloc(
 	int		ret;
 
 #ifdef _SC_LEVEL1_DCACHE_LINESIZE
+	long		l1_dcache;
+
 	/* Try to prevent cache pingpong by aligning to cacheline size. */
-	size = max(size, sysconf(_SC_LEVEL1_DCACHE_LINESIZE));
+	l1_dcache = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
+	if (l1_dcache > 0)
+		size = roundup(size, l1_dcache);
 #endif
 
 	ptv = malloc(PTVAR_SIZE(nr, size));
@@ -88,17 +92,26 @@  ptvar_get(
 	int		*retp)
 {
 	void		*p;
+	int		ret;
 
 	p = pthread_getspecific(ptv->key);
 	if (!p) {
 		pthread_mutex_lock(&ptv->lock);
 		assert(ptv->nr_used < ptv->nr_counters);
 		p = &ptv->data[(ptv->nr_used++) * ptv->data_size];
-		pthread_setspecific(ptv->key, p);
+		ret = pthread_setspecific(ptv->key, p);
+		if (ret)
+			goto out_unlock;
 		pthread_mutex_unlock(&ptv->lock);
 	}
 	*retp = 0;
 	return p;
+
+out_unlock:
+	ptv->nr_used--;
+	pthread_mutex_unlock(&ptv->lock);
+	*retp = ret;
+	return NULL;
 }
 
 /* Iterate all of the per-thread variables. */