linux-kernel - [PATCH 38/49] arch/powerpc: replace cpumask_weight with cpumask_weight

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Date:   Thu, 10 Feb 2022 14:49:22 -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,
        Michael Ellerman <mpe@...erman.id.au>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Srikar Dronamraju <srikar@...ux.vnet.ibm.com>,
        "Gautham R. Shenoy" <ego@...ux.vnet.ibm.com>,
        Valentin Schneider <valentin.schneider@....com>,
        Parth Shah <parth@...ux.ibm.com>,
        Cédric Le Goater <clg@...d.org>,
        Hari Bathini <hbathini@...ux.ibm.com>,
        Rob Herring <robh@...nel.org>,
        Laurent Dufour <ldufour@...ux.ibm.com>,
        Petr Mladek <pmladek@...e.com>,
        John Ogness <john.ogness@...utronix.de>,
        Sudeep Holla <sudeep.holla@....com>,
        Christophe Leroy <christophe.leroy@...roup.eu>,
        "Naveen N. Rao" <naveen.n.rao@...ux.vnet.ibm.com>,
        Xiongwei Song <sxwjean@...il.com>,
        Arnd Bergmann <arnd@...db.de>, linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH 38/49] arch/powerpc: replace cpumask_weight with cpumask_weight_{eq, ...} where appropriate

PowerPC code uses 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 (or can't be)  met.

Signed-off-by: Yury Norov <yury.norov@...il.com>
---
 arch/powerpc/kernel/smp.c      | 2 +-
 arch/powerpc/kernel/watchdog.c | 2 +-
 arch/powerpc/xmon/xmon.c       | 4 ++--
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index b7fd6a72aa76..8bff748df402 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -1656,7 +1656,7 @@ void start_secondary(void *unused)
 		if (has_big_cores)
 			sibling_mask = cpu_smallcore_mask;
 
-		if (cpumask_weight(mask) > cpumask_weight(sibling_mask(cpu)))
+		if (cpumask_weight_gt(mask, cpumask_weight(sibling_mask(cpu))))
 			shared_caches = true;
 	}
 
diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c
index bfc27496fe7e..62937a077de7 100644
--- a/arch/powerpc/kernel/watchdog.c
+++ b/arch/powerpc/kernel/watchdog.c
@@ -483,7 +483,7 @@ static void start_watchdog(void *arg)
 
 	wd_smp_lock(&flags);
 	cpumask_set_cpu(cpu, &wd_cpus_enabled);
-	if (cpumask_weight(&wd_cpus_enabled) == 1) {
+	if (cpumask_weight_eq(&wd_cpus_enabled, 1)) {
 		cpumask_set_cpu(cpu, &wd_smp_cpus_pending);
 		wd_smp_last_reset_tb = get_tb();
 	}
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index fd72753e8ad5..b423812e94e0 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -469,7 +469,7 @@ static bool wait_for_other_cpus(int ncpus)
 
 	/* We wait for 2s, which is a metric "little while" */
 	for (timeout = 20000; timeout != 0; --timeout) {
-		if (cpumask_weight(&cpus_in_xmon) >= ncpus)
+		if (cpumask_weight_ge(&cpus_in_xmon, ncpus))
 			return true;
 		udelay(100);
 		barrier();
@@ -1338,7 +1338,7 @@ static int cpu_cmd(void)
 			case 'S':
 			case 't':
 				cpumask_copy(&xmon_batch_cpus, &cpus_in_xmon);
-				if (cpumask_weight(&xmon_batch_cpus) <= 1) {
+				if (cpumask_weight_le(&xmon_batch_cpus, 1)) {
 					printf("There are no other cpus in xmon\n");
 					break;
 				}
-- 
2.32.0