[tip:x86/urgent] x86/platform/uv/BAU: Fix congested_response_us not taking effect

From: tip-bot for Justin Ernst
Date: Sun Jul 16 2017 - 05:20:04 EST


Commit-ID: dfc1ed1caef09e6be147f9e8d72631e788ffefd9
Gitweb: http://git.kernel.org/tip/dfc1ed1caef09e6be147f9e8d72631e788ffefd9
Author: Justin Ernst <justin.ernst@xxxxxxx>
AuthorDate: Thu, 13 Jul 2017 13:33:23 -0500
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Sun, 16 Jul 2017 11:05:04 +0200

x86/platform/uv/BAU: Fix congested_response_us not taking effect

Bug fix for the BAU tunable congested_cycles not being set to the user
defined value. Instead of referencing a global variable when deciding
on BAU shutdown, a node will reference its own tunable set
value ( cong_response_us). This results in the user set
tunable value congested_response_us taking effect correctly.

Signed-off-by: Justin Ernst <justin.ernst@xxxxxxx>
Acked-by: Andrew Banman <abanman@xxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: mike.travis@xxxxxxx
Cc: sivanich@xxxxxxx
Link: http://lkml.kernel.org/r/1499970803-282432-1-git-send-email-justin.ernst@xxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/platform/uv/tlb_uv.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c
index d4a61dd..fd87591 100644
--- a/arch/x86/platform/uv/tlb_uv.c
+++ b/arch/x86/platform/uv/tlb_uv.c
@@ -40,7 +40,6 @@ static int timeout_base_ns[] = {
static int timeout_us;
static bool nobau = true;
static int nobau_perm;
-static cycles_t congested_cycles;

/* tunables: */
static int max_concurr = MAX_BAU_CONCURRENT;
@@ -829,10 +828,10 @@ static void record_send_stats(cycles_t time1, cycles_t time2,
if ((completion_status == FLUSH_COMPLETE) && (try == 1)) {
bcp->period_requests++;
bcp->period_time += elapsed;
- if ((elapsed > congested_cycles) &&
+ if ((elapsed > usec_2_cycles(bcp->cong_response_us)) &&
(bcp->period_requests > bcp->cong_reps) &&
((bcp->period_time / bcp->period_requests) >
- congested_cycles)) {
+ usec_2_cycles(bcp->cong_response_us))) {
stat->s_congested++;
disable_for_period(bcp, stat);
}
@@ -2228,7 +2227,6 @@ static int __init uv_bau_init(void)
}

nuvhubs = uv_num_possible_blades();
- congested_cycles = usec_2_cycles(congested_respns_us);

uv_base_pnode = 0x7fffffff;
for (uvhub = 0; uvhub < nuvhubs; uvhub++) {