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[PATCH][2.5][4/14] smp_call_function_on_cpu - MIPS

To: Linux Kernel <linux-kernel@vger.kernel.org>
Subject: [PATCH][2.5][4/14] smp_call_function_on_cpu - MIPS
From: Zwane Mwaikambo <zwane@zwane.ca>
Date: Fri, 14 Feb 2003 04:33:43 -0500 (EST)
Cc: Linus Torvalds <torvalds@transmeta.com>, "" <linux-mips@linux-mips.org>
Original-recipient: rfc822;linux-mips@linux-mips.org
Sender: linux-mips-bounce@linux-mips.org
 smp.c |   43 +++++++++++++++++++++++++++++--------------
 1 files changed, 29 insertions(+), 14 deletions(-)

Index: linux-2.5.60/arch/mips/kernel/smp.c
===================================================================
RCS file: /build/cvsroot/linux-2.5.60/arch/mips/kernel/smp.c,v
retrieving revision 1.1.1.1
diff -u -r1.1.1.1 smp.c
--- linux-2.5.60/arch/mips/kernel/smp.c 10 Feb 2003 22:15:04 -0000      1.1.1.1
+++ linux-2.5.60/arch/mips/kernel/smp.c 14 Feb 2003 06:09:00 -0000
@@ -185,22 +185,32 @@
        smp_call_function(reschedule_this_cpu, NULL, 0, 0);
 }
 
-
 /*
- * The caller of this wants the passed function to run on every cpu.  If wait
- * is set, wait until all cpus have finished the function before returning.
- * The lock is here to protect the call structure.
+ * smp_call_function_on_cpu - Runs func on all processors in the mask
+ *
+ * @func: The function to run. This must be fast and non-blocking.
+ * @info: An arbitrary pointer to pass to the function.
+ * @wait: If true, wait (atomically) until function has completed on other 
CPUs.
+ * @mask The bitmask of CPUs to call the function
+ * 
+ * Returns 0 on success, else a negative status code. Does not return until
+ * remote CPUs are nearly ready to execute func or have executed it.
+ *
  * You must not call this function with disabled interrupts or from a
  * hardware interrupt handler or from a bottom half handler.
  */
-int smp_call_function (void (*func) (void *info), void *info, int retry, 
-                                                               int wait)
+
+int smp_call_function_on_cpu (void (*func) (void *info), void *info, int wait,
+                               unsigned long mask)
 {
-       int cpus = smp_num_cpus - 1;
-       int i;
+       int cpu, i, num_cpus;
 
-       if (smp_num_cpus < 2) {
-               return 0;
+       cpu = get_cpu();
+       mask &= ~(1UL << cpu);
+       num_cpus = hweight32(mask);
+       if (num_cpus == 0) {
+               put_cpu_no_resched();
+               return -EINVAL;
        }
 
        spin_lock(&smp_fn_call.lock);
@@ -209,19 +219,24 @@
        smp_fn_call.fn = func;
        smp_fn_call.data = info;
 
-       for (i = 0; i < smp_num_cpus; i++) {
-               if (i != smp_processor_id()) {
+       for (i = 0; i < NR_CPUS; i++) {
+               if (cpu_online(i) && ((1UL << i) & mask))
                        /* Call the board specific routine */
                        core_call_function(i);
-               }
        }
 
        if (wait) {
-               while(atomic_read(&smp_fn_call.finished) != cpus) {}
+               while(atomic_read(&smp_fn_call.finished) != num_cpus) {}
        }
 
        spin_unlock(&smp_fn_call.lock);
+       put_cpu_no_resched();
        return 0;
+}
+
+int smp_call_function (void (*func) (void *info), void *info, int retry, int 
wait)
+{
+       return smp_call_function_on_cpu(func, info, wait, cpu_online_map);
 }
 
 void synchronize_irq(void)

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