[PATCH v2 2/3] cpuacct: Use loop to avoid copies of the similar code in cpuacct_stats_show()

From: Zhao Lei
Date: Fri May 13 2016 - 06:22:00 EST


Currently we have copies of the similar code for each cpustat(system/user)
in cpuacct_stats_show(), this patch use loop instead.
Only a little cleanup.

Signed-off-by: Zhao Lei <zhaolei@xxxxxxxxxxxxxx>
---
kernel/sched/cpuacct.c | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 74241eb..677cd1a 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -243,27 +243,26 @@ static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
static int cpuacct_stats_show(struct seq_file *sf, void *v)
{
struct cpuacct *ca = css_ca(seq_css(sf));
+ s64 val[CPUACCT_STAT_NSTATS];
int cpu;
- s64 val = 0;
+ int stat;

+ memset(val, 0, sizeof(val));
for_each_possible_cpu(cpu) {
- struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
- val += kcpustat->cpustat[CPUTIME_USER];
- val += kcpustat->cpustat[CPUTIME_NICE];
- }
- val = cputime64_to_clock_t(val);
- seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_USER], val);
+ u64 *cpustat = per_cpu_ptr(ca->cpustat, cpu)->cpustat;

- val = 0;
- for_each_possible_cpu(cpu) {
- struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
- val += kcpustat->cpustat[CPUTIME_SYSTEM];
- val += kcpustat->cpustat[CPUTIME_IRQ];
- val += kcpustat->cpustat[CPUTIME_SOFTIRQ];
+ val[CPUACCT_STAT_USER] += cpustat[CPUTIME_USER];
+ val[CPUACCT_STAT_USER] += cpustat[CPUTIME_NICE];
+ val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_SYSTEM];
+ val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_IRQ];
+ val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_SOFTIRQ];
}

- val = cputime64_to_clock_t(val);
- seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val);
+ for (stat = 0; stat < CPUACCT_STAT_NSTATS; stat++) {
+ seq_printf(sf, "%s %lld\n",
+ cpuacct_stat_desc[stat],
+ cputime64_to_clock_t(val[stat]));
+ }

return 0;
}
--
1.8.5.1