From 44dba3d5d6a10685fb15bd1954e62016334825e0 Mon Sep 17 00:00:00 2001 From: Iulia Manda Date: Fri, 31 Oct 2014 02:13:31 +0200 Subject: sched: Refactor task_struct to use numa_faults instead of numa_* pointers This patch simplifies task_struct by removing the four numa_* pointers in the same array and replacing them with the array pointer. By doing this, on x86_64, the size of task_struct is reduced by 3 ulong pointers (24 bytes on x86_64). A new parameter is added to the task_faults_idx function so that it can return an index to the correct offset, corresponding with the old precalculated pointers. All of the code in sched/ that depended on task_faults_idx and numa_* was changed in order to match the new logic. Signed-off-by: Iulia Manda Signed-off-by: Peter Zijlstra (Intel) Cc: mgorman@suse.de Cc: dave@stgolabs.net Cc: riel@redhat.com Cc: Linus Torvalds Link: http://lkml.kernel.org/r/20141031001331.GA30662@winterfell Signed-off-by: Ingo Molnar --- include/linux/sched.h | 31 +++++++++++++------------------ 1 file changed, 13 insertions(+), 18 deletions(-) (limited to 'include') diff --git a/include/linux/sched.h b/include/linux/sched.h index 4400ddc..bd7c14b 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1597,28 +1597,23 @@ struct task_struct { struct numa_group *numa_group; /* - * Exponential decaying average of faults on a per-node basis. - * Scheduling placement decisions are made based on the these counts. - * The values remain static for the duration of a PTE scan + * numa_faults is an array split into four regions: + * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer + * in this precise order. + * + * faults_memory: Exponential decaying average of faults on a per-node + * basis. Scheduling placement decisions are made based on these + * counts. The values remain static for the duration of a PTE scan. + * faults_cpu: Track the nodes the process was running on when a NUMA + * hinting fault was incurred. + * faults_memory_buffer and faults_cpu_buffer: Record faults per node + * during the current scan window. When the scan completes, the counts + * in faults_memory and faults_cpu decay and these values are copied. */ - unsigned long *numa_faults_memory; + unsigned long *numa_faults; unsigned long total_numa_faults; /* - * numa_faults_buffer records faults per node during the current - * scan window. When the scan completes, the counts in - * numa_faults_memory decay and these values are copied. - */ - unsigned long *numa_faults_buffer_memory; - - /* - * Track the nodes the process was running on when a NUMA hinting - * fault was incurred. - */ - unsigned long *numa_faults_cpu; - unsigned long *numa_faults_buffer_cpu; - - /* * numa_faults_locality tracks if faults recorded during the last * scan window were remote/local. The task scan period is adapted * based on the locality of the faults with different weights -- cgit v1.1