From: Heiko Carstens Date: Tue, 24 Jun 2025 14:34:35 +0000 (+0200) Subject: s390/smp: Remove conditional emergency signal order code usage X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0cb39c9738903c2b69bddb5b767f0eae0213c1d5;p=thirdparty%2Fkernel%2Fstable.git s390/smp: Remove conditional emergency signal order code usage pcpu_ec_call() uses either the external call or emergency signal order code to signal (aka send an IPI) to a remote CPU. If the remote CPU is not running the emergency signal order is used. Measurements show that always using the external order code is at least as good, and sometimes even better, than the existing code. Therefore remove emergency signal order code usage from pcpu_ec_call(). Suggested-by: Christian Borntraeger Acked-by: Christian Borntraeger Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev --- diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 81f12bb77f62..6435c5632bc9 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -175,13 +175,10 @@ static struct pcpu *pcpu_find_address(const struct cpumask *mask, u16 address) static void pcpu_ec_call(struct pcpu *pcpu, int ec_bit) { - int order; - if (test_and_set_bit(ec_bit, &pcpu->ec_mask)) return; - order = pcpu_running(pcpu) ? SIGP_EXTERNAL_CALL : SIGP_EMERGENCY_SIGNAL; pcpu->ec_clk = get_tod_clock_fast(); - pcpu_sigp_retry(pcpu, order, 0); + pcpu_sigp_retry(pcpu, SIGP_EXTERNAL_CALL, 0); } static int pcpu_alloc_lowcore(struct pcpu *pcpu, int cpu)