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-rw-r--r--arch/riscv/kernel/smp.c49
1 files changed, 0 insertions, 49 deletions
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 9253de5d91b6..b2537ffa855c 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -205,52 +205,3 @@ void smp_send_reschedule(int cpu)
send_ipi_message(cpumask_of(cpu), IPI_RESCHEDULE);
}
-/*
- * Performs an icache flush for the given MM context. RISC-V has no direct
- * mechanism for instruction cache shoot downs, so instead we send an IPI that
- * informs the remote harts they need to flush their local instruction caches.
- * To avoid pathologically slow behavior in a common case (a bunch of
- * single-hart processes on a many-hart machine, ie 'make -j') we avoid the
- * IPIs for harts that are not currently executing a MM context and instead
- * schedule a deferred local instruction cache flush to be performed before
- * execution resumes on each hart.
- */
-void flush_icache_mm(struct mm_struct *mm, bool local)
-{
- unsigned int cpu;
- cpumask_t others, hmask, *mask;
-
- preempt_disable();
-
- /* Mark every hart's icache as needing a flush for this MM. */
- mask = &mm->context.icache_stale_mask;
- cpumask_setall(mask);
- /* Flush this hart's I$ now, and mark it as flushed. */
- cpu = smp_processor_id();
- cpumask_clear_cpu(cpu, mask);
- local_flush_icache_all();
-
- /*
- * Flush the I$ of other harts concurrently executing, and mark them as
- * flushed.
- */
- cpumask_andnot(&others, mm_cpumask(mm), cpumask_of(cpu));
- local |= cpumask_empty(&others);
- if (mm != current->active_mm || !local) {
- cpumask_clear(&hmask);
- riscv_cpuid_to_hartid_mask(&others, &hmask);
- sbi_remote_fence_i(hmask.bits);
- } else {
- /*
- * It's assumed that at least one strongly ordered operation is
- * performed on this hart between setting a hart's cpumask bit
- * and scheduling this MM context on that hart. Sending an SBI
- * remote message will do this, but in the case where no
- * messages are sent we still need to order this hart's writes
- * with flush_icache_deferred().
- */
- smp_mb();
- }
-
- preempt_enable();
-}