linux-kernel - [PATCH] perf/x86/intel/uncore: Drop unnecessary NULL checks after container

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Date:   Mon, 10 May 2021 15:48:49 -0700
From:   Guenter Roeck <linux@...ck-us.net>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     x86@...nel.org, linux-perf-users@...r.kernel.org,
        linux-kernel@...r.kernel.org, Guenter Roeck <linux@...ck-us.net>
Subject: [PATCH] perf/x86/intel/uncore: Drop unnecessary NULL checks after container_of

The parameter passed to pmu_enable and pmu_disable functions can not be
NULL because it is dereferenced by the caller. That means the result of
container_of() on that parameter can also never be NULL. The existing
NULL checks are therefore unnecessary and misleading. Remove them.

This change was made automatically with the following Coccinelle script.

@@
type t;
identifier v;
statement s;
@@

<+...
(
  t v = container_of(...);
|
  v = container_of(...);
)
  ...
  when != v
- if (\( !v \| v == NULL \) ) s
...+>

Signed-off-by: Guenter Roeck <linux@...ck-us.net>
---
 arch/x86/events/intel/uncore.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/x86/events/intel/uncore.c b/arch/x86/events/intel/uncore.c
index df7b07d7fdcb..9bf4dbbc26e2 100644
--- a/arch/x86/events/intel/uncore.c
+++ b/arch/x86/events/intel/uncore.c
@@ -801,8 +801,6 @@ static void uncore_pmu_enable(struct pmu *pmu)
 	struct intel_uncore_box *box;
 
 	uncore_pmu = container_of(pmu, struct intel_uncore_pmu, pmu);
-	if (!uncore_pmu)
-		return;
 
 	box = uncore_pmu_to_box(uncore_pmu, smp_processor_id());
 	if (!box)
@@ -818,8 +816,6 @@ static void uncore_pmu_disable(struct pmu *pmu)
 	struct intel_uncore_box *box;
 
 	uncore_pmu = container_of(pmu, struct intel_uncore_pmu, pmu);
-	if (!uncore_pmu)
-		return;
 
 	box = uncore_pmu_to_box(uncore_pmu, smp_processor_id());
 	if (!box)
-- 
2.25.1