Commit f1268214 authored by Mario Limonciello's avatar Mario Limonciello Committed by Borislav Petkov (AMD)
Browse files

x86/itmt: Add debugfs file to show core priorities 



Multiple drivers can report priorities to ITMT. To aid in debugging
any issues with the values reported by drivers introduce a debugfs
file to read out the values.

Signed-off-by: default avatarMario Limonciello <mario.limonciello@amd.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Acked-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/20250609200518.3616080-14-superm1@kernel.org
parent 13bc67a9

arch/x86/kernel/itmt.c

+23 −0
Original line number Diff line number Diff line
@@ -59,6 +59,18 @@ static ssize_t sched_itmt_enabled_write(struct file *filp, 
	return result;

}



static int sched_core_priority_show(struct seq_file *s, void *unused)

{

	int cpu;



	seq_puts(s, "CPU #\tPriority\n");

	for_each_possible_cpu(cpu)

		seq_printf(s, "%d\t%d\n", cpu, arch_asym_cpu_priority(cpu));



	return 0;

}

DEFINE_SHOW_ATTRIBUTE(sched_core_priority);



static const struct file_operations dfs_sched_itmt_fops = {

	.read =         debugfs_read_file_bool,

	.write =        sched_itmt_enabled_write,
@@ -67,6 +79,7 @@ static const struct file_operations dfs_sched_itmt_fops = { 
};



static struct dentry *dfs_sched_itmt;

static struct dentry *dfs_sched_core_prio;



/**

 * sched_set_itmt_support() - Indicate platform supports ITMT
@@ -102,6 +115,14 @@ int sched_set_itmt_support(void) 
		return -ENOMEM;

	}



	dfs_sched_core_prio = debugfs_create_file("sched_core_priority", 0644,

						  arch_debugfs_dir, NULL,

						  &sched_core_priority_fops);

	if (IS_ERR_OR_NULL(dfs_sched_core_prio)) {

		dfs_sched_core_prio = NULL;

		return -ENOMEM;

	}



	sched_itmt_capable = true;



	sysctl_sched_itmt_enabled = 1;
@@ -133,6 +154,8 @@ void sched_clear_itmt_support(void) 


	debugfs_remove(dfs_sched_itmt);

	dfs_sched_itmt = NULL;

	debugfs_remove(dfs_sched_core_prio);

	dfs_sched_core_prio = NULL;



	if (sysctl_sched_itmt_enabled) {

		/* disable sched_itmt if we are no longer ITMT capable */