[PATCH 2/2 v4] cxl/region: Use cond_guard() in show_targetN()

From: Fabio M. De Francesco
Date: Thu Feb 08 2024 - 08:05:28 EST


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>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
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 ce0e2d82bb2b..704102f75c14 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");
- else
- rc = sysfs_emit(buf, "%s\n", dev_name(&cxled->cxld.dev));
-out:
- up_read(&cxl_region_rwsem);
+ return sysfs_emit(buf, "\n");

- 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