linux-kernel - [PATCH 42/54] firmware: pcsi: replace cpumask_weight with cpumask_weight

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sun, 23 Jan 2022 10:39:13 -0800
From:   Yury Norov <yury.norov@...il.com>
To:     Yury Norov <yury.norov@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Peter Zijlstra <peterz@...radead.org>,
        David Laight <David.Laight@...lab.com>,
        Joe Perches <joe@...ches.com>, Dennis Zhou <dennis@...nel.org>,
        Emil Renner Berthing <kernel@...il.dk>,
        Nicholas Piggin <npiggin@...il.com>,
        Matti Vaittinen <matti.vaittinen@...rohmeurope.com>,
        Alexey Klimov <aklimov@...hat.com>,
        linux-kernel@...r.kernel.org, Mark Rutland <mark.rutland@....com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@....com>,
        linux-arm-kernel@...ts.infradead.org
Subject: [PATCH 42/54] firmware: pcsi: replace cpumask_weight with cpumask_weight_eq

down_and_up_cpus() calls cpumask_weight() to compare the weight of
cpumask with a given number. We can do it more efficiently with
cpumask_weight_{eq, ...} because conditional cpumask_weight may stop
traversing the cpumask earlier, as soon as condition is met.

Signed-off-by: Yury Norov <yury.norov@...il.com>
---
 drivers/firmware/psci/psci_checker.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/psci/psci_checker.c b/drivers/firmware/psci/psci_checker.c
index 116eb465cdb4..90c9473832a9 100644
--- a/drivers/firmware/psci/psci_checker.c
+++ b/drivers/firmware/psci/psci_checker.c
@@ -90,7 +90,7 @@ static unsigned int down_and_up_cpus(const struct cpumask *cpus,
 		 * cpu_down() checks the number of online CPUs before the TOS
 		 * resident CPU.
 		 */
-		if (cpumask_weight(offlined_cpus) + 1 == nb_available_cpus) {
+		if (cpumask_weight_eq(offlined_cpus, nb_available_cpus - 1)) {
 			if (ret != -EBUSY) {
 				pr_err("Unexpected return code %d while trying "
 				       "to power down last online CPU %d\n",
-- 
2.30.2