Re: [PATCH 2/2] cxl/region: Use cond_guard() in show_targetN()

From: Ira Weiny
Date: Mon Feb 05 2024 - 12:07:05 EST


Fabio M. De Francesco wrote:
> Use cond_guard() in show_target() to not open code an up_read() in an 'out'
> block. If the down_read_interruptible() fails, the statement passed to the
> second argument of cond_guard() returns -EINTR.
>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Suggested-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> Suggested-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> Signed-off-by: Fabio M. De Francesco <fabio.maria.de.francesco@xxxxxxxxxxxxxxx>
> ---
> drivers/cxl/core/region.c | 16 ++++------------
> 1 file changed, 4 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 0f05692bfec3..bd3236786a25 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -666,28 +666,20 @@ static size_t show_targetN(struct cxl_region *cxlr, char *buf, int pos)
> {
> struct cxl_region_params *p = &cxlr->params;
> struct cxl_endpoint_decoder *cxled;
> - int rc;
>
> - rc = down_read_interruptible(&cxl_region_rwsem);
> - if (rc)
> - return rc;
> + cond_guard(rwsem_read_intr, return -EINTR, &cxl_region_rwsem);
>
> if (pos >= p->interleave_ways) {
> dev_dbg(&cxlr->dev, "position %d out of range %d\n", pos,
> p->interleave_ways);
> - rc = -ENXIO;
> - goto out;
> + return -ENXIO;
> }
>
> cxled = p->targets[pos];
> if (!cxled)
> - rc = sysfs_emit(buf, "\n");
> + return sysfs_emit(buf, "\n");
> else

NIT: This else is not needed anymore.

Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>

> - rc = sysfs_emit(buf, "%s\n", dev_name(&cxled->cxld.dev));
> -out:
> - up_read(&cxl_region_rwsem);
> -
> - return rc;
> + return sysfs_emit(buf, "%s\n", dev_name(&cxled->cxld.dev));
> }
>
> static int match_free_decoder(struct device *dev, void *data)
> --
> 2.43.0
>