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authorDimitri Sivanich <sivanich@sgi.com>2016-04-30 00:54:22 +0300
committerIngo Molnar <mingo@kernel.org>2016-05-04 09:48:51 +0300
commit40bfb8eedf1e7fa0535c685ff1000c05bcf7a637 (patch)
tree09970d586c957464d9797157e4e01e736aa33ee0 /drivers/misc/sgi-gru
parentc85375cd19966d5dd854cd8b8eada9be8f21fac1 (diff)
downloadlinux-40bfb8eedf1e7fa0535c685ff1000c05bcf7a637.tar.xz
x86/platform/UV: Remove Obsolete GRU MMR address translation
Use no-op messages in place of cross-partition interrupts when nacking a put message in the GRU. This allows us to remove MMR's as a destination from the GRU driver. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Dimitri Sivanich <sivanich@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215406.012228480@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/misc/sgi-gru')
-rw-r--r--drivers/misc/sgi-gru/grukservices.c38
1 files changed, 22 insertions, 16 deletions
diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c
index 967b9dd24fe9..030769018461 100644
--- a/drivers/misc/sgi-gru/grukservices.c
+++ b/drivers/misc/sgi-gru/grukservices.c
@@ -718,8 +718,8 @@ cberr:
static int send_message_put_nacked(void *cb, struct gru_message_queue_desc *mqd,
void *mesg, int lines)
{
- unsigned long m, *val = mesg, gpa, save;
- int ret;
+ unsigned long m;
+ int ret, loops = 200; /* experimentally determined */
m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
if (lines == 2) {
@@ -735,22 +735,28 @@ static int send_message_put_nacked(void *cb, struct gru_message_queue_desc *mqd,
return MQE_OK;
/*
- * Send a cross-partition interrupt to the SSI that contains the target
- * message queue. Normally, the interrupt is automatically delivered by
- * hardware but some error conditions require explicit delivery.
- * Use the GRU to deliver the interrupt. Otherwise partition failures
+ * Send a noop message in order to deliver a cross-partition interrupt
+ * to the SSI that contains the target message queue. Normally, the
+ * interrupt is automatically delivered by hardware following mesq
+ * operations, but some error conditions require explicit delivery.
+ * The noop message will trigger delivery. Otherwise partition failures
* could cause unrecovered errors.
*/
- gpa = uv_global_gru_mmr_address(mqd->interrupt_pnode, UVH_IPI_INT);
- save = *val;
- *val = uv_hub_ipi_value(mqd->interrupt_apicid, mqd->interrupt_vector,
- dest_Fixed);
- gru_vstore_phys(cb, gpa, gru_get_tri(mesg), IAA_REGISTER, IMA);
- ret = gru_wait(cb);
- *val = save;
- if (ret != CBS_IDLE)
- return MQE_UNEXPECTED_CB_ERR;
- return MQE_OK;
+ do {
+ ret = send_noop_message(cb, mqd, mesg);
+ } while ((ret == MQIE_AGAIN || ret == MQE_CONGESTION) && (loops-- > 0));
+
+ if (ret == MQIE_AGAIN || ret == MQE_CONGESTION) {
+ /*
+ * Don't indicate to the app to resend the message, as it's
+ * already been successfully sent. We simply send an OK
+ * (rather than fail the send with MQE_UNEXPECTED_CB_ERR),
+ * assuming that the other side is receiving enough
+ * interrupts to get this message processed anyway.
+ */
+ ret = MQE_OK;
+ }
+ return ret;
}
/*