Hi Jonathan,

On 28/07/2025 11:08, Jonathan Cameron wrote:

quoted

quoted

+static struct acpi_table_header *get_table(void)
+{
+	struct acpi_table_header *table;
+	acpi_status status;
+
+	if (acpi_disabled || !system_supports_mpam())
+		return NULL;
+
+	status = acpi_get_table(ACPI_SIG_MPAM, 0, &table);
+	if (ACPI_FAILURE(status))
+		return NULL;
+
+	if (table->revision != 1)

Missing an acpi_put_table()

Oops,

I'm messing around with ACQUIRE() that is queued in the CXL tree
for the coming merge window and noticed this.
https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git/log/?h=for-6.17/cleanup-acquire

(not more C++!)

Interestingly this is a new corner case where we want conditional locking
style handling but with return_ptr() style handling. Maybe too much of a niche
to bother with infrastructure.

Worth noting though that one layer up it is probably worth something like:

DEFINE_FREE(acpi_table_mpam, struct acpi_table_header *, if (_T) acpi_put_table(_T));

That enables nice clean code like:


static int __init acpi_mpam_parse(void)
{
	struct acpi_table_header *mpam = __free(acpi_table_mpam) = get_table();

	if (!mpam)
		return 0;

	return _parse_table;
}

I've got bits of that from your PPTT suggestions. I ended up folding the get_table()
helper in here.

count_msc() gets the same treatment and the cleanup thing lets _count_msc() be folded into it.


Thanks,

James

This series was big enough that I'm spinning a single 'suggested changes'
patch on top of it that includes stuff like this.  Might take another day or so.

Jonathan