Re: [PATCH] How to get number of physical CPU in linux from user space?

[Robert Love <rml@tech9.net>]

On Fri, 2002-10-25 at 15:13, Dave Jones wrote:

> Should this be wrapped in a if (cpu_has_ht(c)) { }  ?
> Seems silly to be displaying HT information on non-HT CPUs.

I am neutral, but is fine with me. It is just "cpu_has_ht", btw.

Take two...

This displays the physical processor id and number of siblings of each
processor in /proc/cpuinfo.

	Robert Love

 .proc.c.swp |binary
 proc.c      |    7 +++++++
 2 files changed, 7 insertions(+)

diff -urN linux-2.5.44/arch/i386/kernel/cpu/proc.c linux/arch/i386/kernel/cpu/proc.c
--- linux-2.5.44/arch/i386/kernel/cpu/proc.c	2002-10-19 00:02:29.000000000 -0400
+++ linux/arch/i386/kernel/cpu/proc.c	2002-10-25 15:18:03.000000000 -0400
@@ -17,6 +17,7 @@
 	 * applications want to get the raw CPUID data, they should access
 	 * /dev/cpu/<cpu_nr>/cpuid instead.
 	 */
+	extern int phys_proc_id[NR_CPUS];
 	static char *x86_cap_flags[] = {
 		/* Intel-defined */
 	        "fpu", "vme", "de", "pse", "tsc", "msr", "pae", "mce",
@@ -74,6 +75,12 @@
 	/* Cache size */
 	if (c->x86_cache_size >= 0)
 		seq_printf(m, "cache size\t: %d KB\n", c->x86_cache_size);
+#ifdef CONFIG_SMP
+	if (cpu_has_ht) {
+		seq_printf(m, "physical processor ID\t: %d\n", phys_proc_id[n]);
+		seq_printf(m, "number of siblings\t: %d\n", smp_num_siblings);
+	}
+#endif
 	
 	/* We use exception 16 if we have hardware math and we've either seen it or the CPU claims it is internal */
 	fpu_exception = c->hard_math && (ignore_irq13 || cpu_has_fpu);