linux-kernel - [RFC PATCH mpam mpam/snapshot/v6.12-rc1 v2 2/6] arm

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20241119135104.595630-3-zengheng4@huawei.com>
Date: Tue, 19 Nov 2024 21:51:00 +0800
From: Zeng Heng <zengheng4@...wei.com>
To: <james.morse@....com>, <Dave.Martin@....com>
CC: <linux-kernel@...r.kernel.org>, <jonathan.cameron@...wei.com>,
	<xiexiuqi@...wei.com>, <linux-arm-kernel@...ts.infradead.org>
Subject: [RFC PATCH mpam mpam/snapshot/v6.12-rc1 v2 2/6] arm_mpam: Create reqPARTIDs resource bitmap

The driver checks whether mpam_partid_max and mpam_intpartid_max are equal
as a basis for supporting reqPARTID. If this feature is supported, use a
bitmap to represent whether the target reqPARTID is available or not.
Create the bitmap during monitor initialization, and the destructor is
called during the monitor exit process.

It is noted that the reqpartid_free_map reserves the first reqPARTID under
each intPARTID (which is equal to the corresponding intPARTID itself). By
default, assigns it to the corresponding control group for use in
monitoring.

Signed-off-by: Zeng Heng <zengheng4@...wei.com>
---
 drivers/platform/arm64/mpam/mpam_resctrl.c | 33 ++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/drivers/platform/arm64/mpam/mpam_resctrl.c b/drivers/platform/arm64/mpam/mpam_resctrl.c
index ac3d228befcf..dfd4125875d7 100644
--- a/drivers/platform/arm64/mpam/mpam_resctrl.c
+++ b/drivers/platform/arm64/mpam/mpam_resctrl.c
@@ -1005,6 +1005,33 @@ static void mpam_resctrl_monitor_init(struct mpam_class *class,
 	return;
 }
 
+static unsigned long *reqpartid_free_map;
+static int reqpartid_free_map_len;
+
+static int reqpartid_create(void)
+{
+	u32 reqpartid_num = get_num_reqpartid();
+	int i;
+
+	reqpartid_free_map = bitmap_alloc(reqpartid_num, GFP_KERNEL);
+	if (!reqpartid_free_map)
+		return -ENOMEM;
+
+	bitmap_fill(reqpartid_free_map, reqpartid_num);
+
+	/* Reserved for the internal partIDs mapping */
+	for (i = 0; i < resctrl_arch_get_num_closid(NULL); i++)
+		__clear_bit(i, reqpartid_free_map);
+
+	reqpartid_free_map_len = reqpartid_num;
+	return 0;
+}
+
+static void reqpartid_destroy(void)
+{
+	bitmap_free(reqpartid_free_map);
+}
+
 int mpam_resctrl_setup(void)
 {
 	int err = 0;
@@ -1052,6 +1079,10 @@ int mpam_resctrl_setup(void)
 
 	cpus_read_unlock();
 
+	err = reqpartid_create();
+	if (err)
+		return err;
+
 	if (!err && !exposed_alloc_capable && !exposed_mon_capable)
 		err = -EOPNOTSUPP;
 
@@ -1080,6 +1111,8 @@ static void mpam_resctrl_exit(void)
 
 	WRITE_ONCE(resctrl_enabled, false);
 	resctrl_exit();
+
+	reqpartid_destroy();
 }
 
 
-- 
2.25.1