Commit 826e99be authored by James Hogan's avatar James Hogan Committed by Ralf Baechle
Browse files

MIPS: SMP: Update cpu_foreign_map on CPU disable 



When a CPU is disabled via CPU hotplug, cpu_foreign_map is not updated.
This could result in cache management SMP calls being sent to offline
CPUs instead of online siblings in the same core.

Add a call to calculate_cpu_foreign_map() in the various MIPS cpu
disable callbacks after set_cpu_online(). All cases are updated for
consistency and to keep cpu_foreign_map strictly up to date, not just
those which may support hardware multithreading.

Fixes: cccf34e9 ("MIPS: c-r4k: Fix cache flushing for MT cores")
Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Hongliang Tao <taohl@lemote.com>
Cc: Hua Yan <yanh@lemote.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13799/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent a05c3920

arch/mips/cavium-octeon/smp.c

+1 −0
Original line number Diff line number Diff line
@@ -271,6 +271,7 @@ static int octeon_cpu_disable(void) 
		return -ENOTSUPP;



	set_cpu_online(cpu, false);

	calculate_cpu_foreign_map();

	cpumask_clear_cpu(cpu, &cpu_callin_map);

	octeon_fixup_irqs();

arch/mips/include/asm/smp.h

+2 −0
Original line number Diff line number Diff line
@@ -53,6 +53,8 @@ extern cpumask_t cpu_coherent_mask; 


extern void asmlinkage smp_bootstrap(void);



extern void calculate_cpu_foreign_map(void);



/*

 * this function sends a 'reschedule' IPI to another CPU.

 * it goes straight through and wastes no time serializing

arch/mips/kernel/smp-bmips.c

+1 −0
Original line number Diff line number Diff line
@@ -363,6 +363,7 @@ static int bmips_cpu_disable(void) 
	pr_info("SMP: CPU%d is offline\n", cpu);



	set_cpu_online(cpu, false);

	calculate_cpu_foreign_map();

	cpumask_clear_cpu(cpu, &cpu_callin_map);

	clear_c0_status(IE_IRQ5);

arch/mips/kernel/smp-cps.c

+1 −0
Original line number Diff line number Diff line
@@ -398,6 +398,7 @@ static int cps_cpu_disable(void) 
	atomic_sub(1 << cpu_vpe_id(&current_cpu_data), &core_cfg->vpe_mask);

	smp_mb__after_atomic();

	set_cpu_online(cpu, false);

	calculate_cpu_foreign_map();

	cpumask_clear_cpu(cpu, &cpu_callin_map);



	return 0;

arch/mips/kernel/smp.c

+1 −1
Original line number Diff line number Diff line
@@ -124,7 +124,7 @@ static inline void set_cpu_core_map(int cpu) 
 * Calculate a new cpu_foreign_map mask whenever a

 * new cpu appears or disappears.

 */

static inline void calculate_cpu_foreign_map(void)

void calculate_cpu_foreign_map(void)

{

	int i, k, core_present;

	cpumask_t temp_foreign_map;

CRA Git | Maintained and supported by SUSTech CRA and CCSE