mm: page_alloc: use jump labels to avoid checking number_of_cpusets (664eedde) · Commits · 戴 / test

include/linux/cpuset.h

+26 −3

Original line number	Diff line number	Diff line
		@@ -12,10 +12,31 @@
		#include <linux/cpumask.h>
		#include <linux/nodemask.h>
		#include <linux/mm.h>
		#include <linux/jump_label.h>

		#ifdef CONFIG_CPUSETS

		extern int number_of_cpusets; /* How many cpusets are defined in system? */
		extern struct static_key cpusets_enabled_key;
		static inline bool cpusets_enabled(void)
		{
		return static_key_false(&cpusets_enabled_key);
		}

		static inline int nr_cpusets(void)
		{
		/* jump label reference count + the top-level cpuset */
		return static_key_count(&cpusets_enabled_key) + 1;
		}

		static inline void cpuset_inc(void)
		{
		static_key_slow_inc(&cpusets_enabled_key);
		}

		static inline void cpuset_dec(void)
		{
		static_key_slow_dec(&cpusets_enabled_key);
		}

		extern int cpuset_init(void);
		extern void cpuset_init_smp(void);
		@@ -32,13 +53,13 @@ extern int __cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask);

		static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
		{
		return number_of_cpusets <= 1 \|\|
		return nr_cpusets() <= 1 \|\|
		__cpuset_node_allowed_softwall(node, gfp_mask);
		}

		static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
		{
		return number_of_cpusets <= 1 \|\|
		return nr_cpusets() <= 1 \|\|
		__cpuset_node_allowed_hardwall(node, gfp_mask);
		}

		@@ -124,6 +145,8 @@ static inline void set_mems_allowed(nodemask_t nodemask)

		#else /* !CONFIG_CPUSETS */

		static inline bool cpusets_enabled(void) { return false; }

		static inline int cpuset_init(void) { return 0; }
		static inline void cpuset_init_smp(void) {}

+4 −10

Original line number	Diff line number	Diff line
		@@ -61,12 +61,7 @@
		#include <linux/cgroup.h>
		#include <linux/wait.h>

		/*
		* Tracks how many cpusets are currently defined in system.
		* When there is only one cpuset (the root cpuset) we can
		* short circuit some hooks.
		*/
		int number_of_cpusets __read_mostly;
		struct static_key cpusets_enabled_key __read_mostly = STATIC_KEY_INIT_FALSE;

		/* See "Frequency meter" comments, below. */

		@@ -611,7 +606,7 @@ static int generate_sched_domains(cpumask_var_t **domains,
		goto done;
		}

		csa = kmalloc(number_of_cpusets * sizeof(cp), GFP_KERNEL);
		csa = kmalloc(nr_cpusets() * sizeof(cp), GFP_KERNEL);
		if (!csa)
		goto done;
		csn = 0;
		@@ -1888,7 +1883,7 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
		if (is_spread_slab(parent))
		set_bit(CS_SPREAD_SLAB, &cs->flags);

		number_of_cpusets++;
		cpuset_inc();

		if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &css->cgroup->flags))
		goto out_unlock;
		@@ -1939,7 +1934,7 @@ static void cpuset_css_offline(struct cgroup_subsys_state *css)
		if (is_sched_load_balance(cs))
		update_flag(CS_SCHED_LOAD_BALANCE, cs, 0);

		number_of_cpusets--;
		cpuset_dec();
		clear_bit(CS_ONLINE, &cs->flags);

		mutex_unlock(&cpuset_mutex);
		@@ -1992,7 +1987,6 @@ int __init cpuset_init(void)
		if (!alloc_cpumask_var(&cpus_attach, GFP_KERNEL))
		BUG();

		number_of_cpusets = 1;
		return 0;
		}

+2 −1

Original line number	Diff line number	Diff line
		@@ -1921,7 +1921,8 @@ zonelist_scan:
		if (IS_ENABLED(CONFIG_NUMA) && zlc_active &&
		!zlc_zone_worth_trying(zonelist, z, allowednodes))
		continue;
		if ((alloc_flags & ALLOC_CPUSET) &&
		if (cpusets_enabled() &&
		(alloc_flags & ALLOC_CPUSET) &&
		!cpuset_zone_allowed_softwall(zone, gfp_mask))
		continue;
		BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);