Commit 366a2fd2 authored by Wang ShaoBo's avatar Wang ShaoBo Committed by Yu Liao
Browse files

arm64/mpam: mark partid non-exclusive if self-owned 

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7SVKK



--------------------------------

MPAM manages RMID in a matrix using PARTID as columns and PMG as rows.

 ------------row---------------------->
|
|  RMID  0     1     2     3   ... 255
|        256   257   258   259 ... 511
|        512   513   514   515 ... 767
v        768   769   770   771 ... 1023

Each time mon_groups is created, a new PARTID will be consumed until all
PARTID are exhausted and PMG still has remaining. As a result, RMID
greater than 255 cannot be used. mon_groups in the same resource group
should reuse PARTID to avoid rmid waste.

Fix it by adding 'exclusive' parameter to rmid_remap_bmp_find_step_entry()
  1) Allocate non-exclusive rmid for rmid_alloc()
  2) Allocate exclusive rmid when 'partid = old_reqpartid' for
     resctrl_group_rmid_write(). Otherwise, allocate non-exclusive rmid.

Signed-off-by: default avatarWang ShaoBo <bobo.shaobowang@huawei.com>
Signed-off-by: default avatarYu Liao <liaoyu15@huawei.com>
parent 2e7a3cda

arch/arm64/kernel/mpam/mpam_resctrl.c

+11 −9
Original line number Diff line number Diff line
@@ -919,7 +919,7 @@ static int is_rmid_remap_bmp_full(unsigned long *bmp) 
			bitmap_full(bmp, rmid_remap_matrix.rows));

}



static int rmid_remap_bmp_find_step_entry(int partid)

static int rmid_remap_bmp_find_step_entry(int partid, bool exclusive)

{

	int x, y;

	unsigned long **bmp;
@@ -931,7 +931,7 @@ static int rmid_remap_bmp_find_step_entry(int partid) 
	/* step entry should be non-occupied and aligned */

	bmp = __rmid_remap_bmp(partid);

	if (bmp)

		return (is_rmid_remap_bmp_occ(*bmp) ||

		return ((exclusive && is_rmid_remap_bmp_occ(*bmp)) ||

			!__step_align(partid)) ? -ENOSPC : partid;



	for_each_rmid_transform_point_from(bmp, x, y, 0) {
@@ -1024,7 +1024,7 @@ static int rmid_to_partid_pmg(int rmid, int *partid, int *pmg) 
	return 0;

}



static int __rmid_alloc(int partid, int pmg)

static int __rmid_alloc(int partid, int pmg, bool exclusive)

{

	int x, y, step, ret, rmid;

	bool checkpmg = false;
@@ -1034,7 +1034,7 @@ static int __rmid_alloc(int partid, int pmg) 
		checkpmg = true;



	/* traverse from first non-occupied and step-aligned entry */

	ret = rmid_remap_bmp_find_step_entry(partid);

	ret = rmid_remap_bmp_find_step_entry(partid, exclusive);

	if (ret < 0)

		goto out;

	partid = ret;
@@ -1084,7 +1084,7 @@ static int __rmid_alloc(int partid, int pmg) 


int rmid_alloc(int partid)

{

	return __rmid_alloc(partid, -1);

	return __rmid_alloc(partid, -1, false);

}



void rmid_free(int rmid)
@@ -1914,6 +1914,7 @@ static ssize_t resctrl_group_rmid_write(struct kernfs_open_file *of, 
	struct rdtgroup *rdtgrp;

	int ret = 0;

	int partid;

	bool exclusive;

	int pmg;

	int rmid;

	int old_rmid;
@@ -1954,15 +1955,16 @@ static ssize_t resctrl_group_rmid_write(struct kernfs_open_file *of, 
		goto unlock;

	}



	ret = __rmid_alloc(partid, pmg);

	old_rmid = rdtgrp->mon.rmid;

	old_reqpartid = rdtgrp->closid.reqpartid;



	exclusive = (partid == old_reqpartid) ? false : true;

	ret = __rmid_alloc(partid, pmg, exclusive);

	if (ret < 0) {

		rdt_last_cmd_puts("set rmid failed\n");

		goto unlock;

	}



	old_rmid = rdtgrp->mon.rmid;

	old_reqpartid = rdtgrp->closid.reqpartid;



	/*

	 * we use intpartid as group control, use reqpartid for config

	 * synchronization and monitor, only update the reqpartid