[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH v5 05/30] ARM: GICv3: allocate LPI pending and property table



Hi Andre,

On 06/04/17 00:18, Andre Przywara wrote:
+static unsigned int max_lpi_bits = 20;
+integer_param("max_lpi_bits", max_lpi_bits);
+
+int gicv3_lpi_init_host_lpis(unsigned int host_lpi_bits)
+{
+    /* An implementation needs to support at least 14 bits of LPI IDs. */
+    max_lpi_bits = max(max_lpi_bits, 14U);

I think we should warn the user if we don't use his command line. He might think he can disable LPIs using it.

+    lpi_data.max_host_lpi_ids = BIT_ULL(min(host_lpi_bits, max_lpi_bits));
+
+    /*
+     * Warn if the number of LPIs are quite high, as the user might not want
+     * to waste megabytes of memory for a mostly empty table.
+     * It's very unlikely that we need more than 24 bits worth of LPIs.
+     */
+    if ( lpi_data.max_host_lpi_ids > BIT(24) )
+        warning_add("Using high number of LPIs, limit memory usage with 
max_lpi_bits\n");
+
+    printk("GICv3: using at most %llu LPIs on the host.\n", MAX_NR_HOST_LPIS);
+
+    return 0;
+}

Cheers,

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.