[PATCH 7/10] __send_IPI_dest_field - i386

Implement __send_IPI_dest_field which can be used to send IPIs when the
"destination shorthand" field of the ICR is set to 00 (destination
field). Use it whenever possible.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@xxxxxxxxxxxxx>
---

diff -urNp linux-2.6.21-rc7-orig/arch/i386/kernel/smp.c linux-2.6.21-rc7/arch/i386/kernel/smp.c
--- linux-2.6.21-rc7-orig/arch/i386/kernel/smp.c 2007-04-18 15:27:48.000000000 +0900
+++ linux-2.6.21-rc7/arch/i386/kernel/smp.c 2007-04-23 16:29:24.000000000 +0900
@@ -165,16 +165,13 @@ void fastcall send_IPI_self(int vector)
}

/*
- * This is only used on smaller machines.
+ * This is used to send an IPI with no shorthand notation (the destination is
+ * specified in bits 56 to 63 of the ICR).
*/
-void send_IPI_mask_bitmask(cpumask_t cpumask, int vector)
+static inline void __send_IPI_dest_field(unsigned long mask, int vector)
{
- unsigned long mask = cpus_addr(cpumask)[0];
unsigned long cfg;
- unsigned long flags;

- local_irq_save(flags);
- WARN_ON(mask & ~cpus_addr(cpu_online_map)[0]);
/*
* Wait for idle.
*/
@@ -195,13 +192,25 @@ void send_IPI_mask_bitmask(cpumask_t cpu
* Send the IPI. The write to APIC_ICR fires this off.
*/
apic_write_around(APIC_ICR, cfg);
+}

+/*
+ * This is only used on smaller machines.
+ */
+void send_IPI_mask_bitmask(cpumask_t cpumask, int vector)
+{
+ unsigned long mask = cpus_addr(cpumask)[0];
+ unsigned long flags;
+
+ local_irq_save(flags);
+ WARN_ON(mask & ~cpus_addr(cpu_online_map)[0]);
+ __send_IPI_dest_field(mask, vector);
local_irq_restore(flags);
}

void send_IPI_mask_sequence(cpumask_t mask, int vector)
{
- unsigned long cfg, flags;
+ unsigned long flags;
unsigned int query_cpu;

/*
@@ -211,30 +220,10 @@ void send_IPI_mask_sequence(cpumask_t ma
*/

local_irq_save(flags);
-
for (query_cpu = 0; query_cpu < NR_CPUS; ++query_cpu) {
if (cpu_isset(query_cpu, mask)) {
-
- /*
- * Wait for idle.
- */
- apic_wait_icr_idle();
-
- /*
- * prepare target chip field
- */
- cfg = __prepare_ICR2(cpu_to_logical_apicid(query_cpu));
- apic_write_around(APIC_ICR2, cfg);
-
- /*
- * program the ICR
- */
- cfg = __prepare_ICR(0, vector);
-
- /*
- * Send the IPI. The write to APIC_ICR fires this off.
- */
- apic_write_around(APIC_ICR, cfg);
+ __send_IPI_dest_field(cpu_to_logical_apicid(query_cpu),
+ vector);
}
}
local_irq_restore(flags);


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