[PATCH] drm/vc4: replace idr_init() by idr_init_base()

From: Deepak R Varma <mh12gx2825@gmail.com>
To: Eric Anholt <eric@anholt.net>, David Airlie <airlied@linux.ie>,
	Daniel Vetter <daniel@ffwll.ch>,
	dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Cc: mh12gx2825@gmail.com, maxime@cerno.tech, mripard@kernel.org
Subject: [PATCH] drm/vc4: replace idr_init() by idr_init_base()
Date: Thu, 5 Nov 2020 23:46:13 +0530	[thread overview]
Message-ID: <20201105181613.GA42968@localhost> (raw)

idr_init() uses base 0 which is an invalid identifier for this driver.
The idr_alloc for this driver uses VC4_PERFMONID_MIN as start value for
ID range and it is #defined to 1. The new function idr_init_base allows
IDR to set the ID lookup from base 1. This avoids all lookups that
otherwise starts from 0 since 0 is always unused / available.

References: commit 6ce711f27500 ("idr: Make 1-based IDRs more efficient")

Signed-off-by: Deepak R Varma <mh12gx2825@gmail.com>
---
 drivers/gpu/drm/vc4/vc4_perfmon.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vc4/vc4_perfmon.c b/drivers/gpu/drm/vc4/vc4_perfmon.c
index f4aa75efd16b..7d40f421d922 100644
--- a/drivers/gpu/drm/vc4/vc4_perfmon.c
+++ b/drivers/gpu/drm/vc4/vc4_perfmon.c
@@ -77,7 +77,7 @@ struct vc4_perfmon *vc4_perfmon_find(struct vc4_file *vc4file, int id)
 void vc4_perfmon_open_file(struct vc4_file *vc4file)
 {
 	mutex_init(&vc4file->perfmon.lock);
-	idr_init(&vc4file->perfmon.idr);
+	idr_init_base(&vc4file->perfmon.idr, 1);
 }
 
 static int vc4_perfmon_idr_del(int id, void *elem, void *data)
-- 
2.25.1

