From bbeee4b2815dd318e9ec9d092d7f79061cc8ba36 Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Mon, 28 Feb 2011 13:32:14 -0500 Subject: [PATCH] arch/tile: warn and retry if an IPI is not accepted by the target cpu Previously we assumed this was impossible, but in fact it can happen. Handle it gracefully by retrying after issuing a warning. Signed-off-by: Chris Metcalf --- arch/tile/kernel/smp.c | 33 +++++++++++++++++++-------------- 1 file changed, 19 insertions(+), 14 deletions(-) diff --git a/arch/tile/kernel/smp.c b/arch/tile/kernel/smp.c index 9575b37a8b75..a4293102ef81 100644 --- a/arch/tile/kernel/smp.c +++ b/arch/tile/kernel/smp.c @@ -36,6 +36,22 @@ static unsigned long __iomem *ipi_mappings[NR_CPUS]; /* Set by smp_send_stop() to avoid recursive panics. */ static int stopping_cpus; +static void __send_IPI_many(HV_Recipient *recip, int nrecip, int tag) +{ + int sent = 0; + while (sent < nrecip) { + int rc = hv_send_message(recip, nrecip, + (HV_VirtAddr)&tag, sizeof(tag)); + if (rc < 0) { + if (!stopping_cpus) /* avoid recursive panic */ + panic("hv_send_message returned %d", rc); + break; + } + WARN_ONCE(rc == 0, "hv_send_message() returned zero\n"); + sent += rc; + } +} + void send_IPI_single(int cpu, int tag) { HV_Recipient recip = { @@ -43,14 +59,13 @@ void send_IPI_single(int cpu, int tag) .x = cpu % smp_width, .state = HV_TO_BE_SENT }; - int rc = hv_send_message(&recip, 1, (HV_VirtAddr)&tag, sizeof(tag)); - BUG_ON(rc <= 0); + __send_IPI_many(&recip, 1, tag); } void send_IPI_many(const struct cpumask *mask, int tag) { HV_Recipient recip[NR_CPUS]; - int cpu, sent; + int cpu; int nrecip = 0; int my_cpu = smp_processor_id(); for_each_cpu(cpu, mask) { @@ -61,17 +76,7 @@ void send_IPI_many(const struct cpumask *mask, int tag) r->x = cpu % smp_width; r->state = HV_TO_BE_SENT; } - sent = 0; - while (sent < nrecip) { - int rc = hv_send_message(recip, nrecip, - (HV_VirtAddr)&tag, sizeof(tag)); - if (rc <= 0) { - if (!stopping_cpus) /* avoid recursive panic */ - panic("hv_send_message returned %d", rc); - break; - } - sent += rc; - } + __send_IPI_many(recip, nrecip, tag); } void send_IPI_allbutself(int tag) -- 2.20.1