>From 6516d48db858f549cf663d61b55188d515746915 Mon Sep 17 00:00:00 2001
From: Akira Yokosawa <akiyks@xxxxxxxxx>
Date: Fri, 15 Dec 2017 23:17:59 +0900
Subject: [PATCH 1/4] count: Get rid of ACCESS_ONCE() in code snippet
Also update code under CodeSamples/count/.
Signed-off-by: Akira Yokosawa <akiyks@xxxxxxxxx>
---
CodeSamples/count/count_lim_sig.c | 26 +++++++++++++-------------
CodeSamples/count/counttorture.h | 8 ++++----
CodeSamples/count/limtorture.h | 18 +++++++++---------
count/count.tex | 28 ++++++++++++++--------------
4 files changed, 40 insertions(+), 40 deletions(-)
diff --git a/CodeSamples/count/count_lim_sig.c b/CodeSamples/count/count_lim_sig.c
index dbe4496..104d116 100644
--- a/CodeSamples/count/count_lim_sig.c
+++ b/CodeSamples/count/count_lim_sig.c
@@ -50,12 +50,12 @@ static void globalize_count(void)
static void flush_local_count_sig(int unused)
{
- if (ACCESS_ONCE(theft) != THEFT_REQ)
+ if (READ_ONCE(theft) != THEFT_REQ)
return;
smp_mb();
- ACCESS_ONCE(theft) = THEFT_ACK;
+ WRITE_ONCE(theft, THEFT_ACK);
if (!counting) {
- ACCESS_ONCE(theft) = THEFT_READY;
+ WRITE_ONCE(theft, THEFT_READY);
}
smp_mb();
}
@@ -68,25 +68,25 @@ static void flush_local_count(void)
for_each_tid(t, tid)
if (theftp[t] != NULL) {
if (*countermaxp[t] == 0) {
- ACCESS_ONCE(*theftp[t]) = THEFT_READY;
+ WRITE_ONCE(*theftp[t], THEFT_READY);
continue;
}
- ACCESS_ONCE(*theftp[t]) = THEFT_REQ;
+ WRITE_ONCE(*theftp[t], THEFT_REQ);
pthread_kill(tid, SIGUSR1);
}
for_each_tid(t, tid) {
if (theftp[t] == NULL)
continue;
- while (ACCESS_ONCE(*theftp[t]) != THEFT_READY) {
+ while (READ_ONCE(*theftp[t]) != THEFT_READY) {
poll(NULL, 0, 1);
- if (ACCESS_ONCE(*theftp[t]) == THEFT_REQ)
+ if (READ_ONCE(*theftp[t]) == THEFT_REQ)
pthread_kill(tid, SIGUSR1);
}
globalcount += *counterp[t];
*counterp[t] = 0;
globalreserve -= *countermaxp[t];
*countermaxp[t] = 0;
- ACCESS_ONCE(*theftp[t]) = THEFT_IDLE;
+ WRITE_ONCE(*theftp[t], THEFT_IDLE);
}
}
@@ -109,16 +109,16 @@ int add_count(unsigned long delta)
counting = 1;
barrier();
- if (countermax - counter >= delta && ACCESS_ONCE(theft) <= THEFT_REQ) {
+ if (countermax - counter >= delta && READ_ONCE(theft) <= THEFT_REQ) {
counter += delta;
fastpath = 1;
}
barrier();
counting = 0;
barrier();
- if (ACCESS_ONCE(theft) == THEFT_ACK) {
+ if (READ_ONCE(theft) == THEFT_ACK) {
smp_mb();
- ACCESS_ONCE(theft) = THEFT_READY;
+ WRITE_ONCE(theft, THEFT_READY);
}
if (fastpath)
return 1;
@@ -150,9 +150,9 @@ int sub_count(unsigned long delta)
barrier();
counting = 0;
barrier();
- if (ACCESS_ONCE(theft) == THEFT_ACK) {
+ if (READ_ONCE(theft) == THEFT_ACK) {
smp_mb();
- ACCESS_ONCE(theft) = THEFT_READY;
+ WRITE_ONCE(theft, THEFT_READY);
}
if (fastpath)
return 1;
diff --git a/CodeSamples/count/counttorture.h b/CodeSamples/count/counttorture.h
index 1565a70..3bfd213 100644
--- a/CodeSamples/count/counttorture.h
+++ b/CodeSamples/count/counttorture.h
@@ -81,9 +81,9 @@ void *count_read_perf_test(void *arg)
run_on(me);
count_register_thread(&k);
atomic_inc(&nthreadsrunning);
- while (ACCESS_ONCE(goflag) == GOFLAG_INIT)
+ while (READ_ONCE(goflag) == GOFLAG_INIT)
poll(NULL, 0, 1);
- while (ACCESS_ONCE(goflag) == GOFLAG_RUN) {
+ while (READ_ONCE(goflag) == GOFLAG_RUN) {
for (i = COUNT_READ_RUN; i > 0; i--) {
j += read_count();
barrier();
@@ -105,9 +105,9 @@ void *count_update_perf_test(void *arg)
count_register_thread(&k);
atomic_inc(&nthreadsrunning);
- while (ACCESS_ONCE(goflag) == GOFLAG_INIT)
+ while (READ_ONCE(goflag) == GOFLAG_INIT)
poll(NULL, 0, 1);
- while (ACCESS_ONCE(goflag) == GOFLAG_RUN) {
+ while (READ_ONCE(goflag) == GOFLAG_RUN) {
for (i = COUNT_UPDATE_RUN; i > 0; i--) {
inc_count();
barrier();
diff --git a/CodeSamples/count/limtorture.h b/CodeSamples/count/limtorture.h
index 20862a9..4866e28 100644
--- a/CodeSamples/count/limtorture.h
+++ b/CodeSamples/count/limtorture.h
@@ -89,7 +89,7 @@ void *count_updown_limit(void *arg)
run_on(me);
count_register_thread();
atomic_inc(&nthreadsrunning);
- while (ACCESS_ONCE(goflag) != GOFLAG_RUN_UP)
+ while (READ_ONCE(goflag) != GOFLAG_RUN_UP)
poll(NULL, 0, 1);
while (add_count(1)) {
n_updates_local++;
@@ -97,7 +97,7 @@ void *count_updown_limit(void *arg)
__get_thread_var(n_updates_pt) += n_updates_local;
smp_mb();
atomic_inc(&n_threads_run_up);
- while (ACCESS_ONCE(goflag) != GOFLAG_RUN_DOWN)
+ while (READ_ONCE(goflag) != GOFLAG_RUN_DOWN)
poll(NULL, 0, 1);
n_updates_local = 0LL;
while (sub_count(1)) {
@@ -106,7 +106,7 @@ void *count_updown_limit(void *arg)
__get_thread_var(n_updates_pt) += n_updates_local;
smp_mb();
atomic_inc(&n_threads_run_down);
- while (ACCESS_ONCE(goflag) != GOFLAG_STOP)
+ while (READ_ONCE(goflag) != GOFLAG_STOP)
poll(NULL, 0, 1);
count_unregister_thread(nthreadsexpected);
return NULL;
@@ -120,7 +120,7 @@ void *count_updown_hog(void *arg)
run_on(me);
count_register_thread();
atomic_inc(&nthreadsrunning);
- while (ACCESS_ONCE(goflag) == GOFLAG_INIT)
+ while (READ_ONCE(goflag) == GOFLAG_INIT)
poll(NULL, 0, 1);
delta = num_online_threads() * 20;
if (!add_count(delta)) {
@@ -130,7 +130,7 @@ void *count_updown_hog(void *arg)
__get_thread_var(n_updates_pt) += delta;
smp_mb();
atomic_inc(&n_threads_hog);
- while (ACCESS_ONCE(goflag) != GOFLAG_STOP)
+ while (READ_ONCE(goflag) != GOFLAG_STOP)
poll(NULL, 0, 1);
count_unregister_thread(nthreadsexpected);
return NULL;
@@ -209,9 +209,9 @@ void *count_read_perf_test(void *arg)
run_on(me);
count_register_thread();
atomic_inc(&nthreadsrunning);
- while (ACCESS_ONCE(goflag) == GOFLAG_INIT)
+ while (READ_ONCE(goflag) == GOFLAG_INIT)
poll(NULL, 0, 1);
- while (ACCESS_ONCE(goflag) == GOFLAG_RUN) {
+ while (READ_ONCE(goflag) == GOFLAG_RUN) {
for (i = COUNT_READ_RUN; i > 0; i--) {
j += read_count();
barrier();
@@ -232,9 +232,9 @@ void *count_update_perf_test(void *arg)
count_register_thread();
atomic_inc(&nthreadsrunning);
- while (ACCESS_ONCE(goflag) == GOFLAG_INIT)
+ while (READ_ONCE(goflag) == GOFLAG_INIT)
poll(NULL, 0, 1);
- while (ACCESS_ONCE(goflag) == GOFLAG_RUN) {
+ while (READ_ONCE(goflag) == GOFLAG_RUN) {
for (i = COUNT_UPDATE_RUN; i > 0; i--) {
add_count(1);
sub_count(1);
diff --git a/count/count.tex b/count/count.tex
index 900c384..277627d 100644
--- a/count/count.tex
+++ b/count/count.tex
@@ -2719,12 +2719,12 @@ and \co{theft} variables, respectively.
8
9 static void flush_local_count_sig(int unused)
10 {
- 11 if (ACCESS_ONCE(theft) != THEFT_REQ)
+ 11 if (READ_ONCE(theft) != THEFT_REQ)
12 return;
13 smp_mb();
- 14 ACCESS_ONCE(theft) = THEFT_ACK;
+ 14 WRITE_ONCE(theft, THEFT_ACK);
15 if (!counting) {
- 16 ACCESS_ONCE(theft) = THEFT_READY;
+ 16 WRITE_ONCE(theft, THEFT_READY);
17 }
18 smp_mb();
19 }
@@ -2737,25 +2737,25 @@ and \co{theft} variables, respectively.
26 for_each_tid(t, tid)
27 if (theftp[t] != NULL) {
28 if (*countermaxp[t] == 0) {
- 29 ACCESS_ONCE(*theftp[t]) = THEFT_READY;
+ 29 WRITE_ONCE(*theftp[t], THEFT_READY);
30 continue;
31 }
- 32 ACCESS_ONCE(*theftp[t]) = THEFT_REQ;
+ 32 WRITE_ONCE(*theftp[t], THEFT_REQ);
33 pthread_kill(tid, SIGUSR1);
34 }
35 for_each_tid(t, tid) {
36 if (theftp[t] == NULL)
37 continue;
- 38 while (ACCESS_ONCE(*theftp[t]) != THEFT_READY) {
+ 38 while (READ_ONCE(*theftp[t]) != THEFT_READY) {
39 poll(NULL, 0, 1);
- 40 if (ACCESS_ONCE(*theftp[t]) == THEFT_REQ)
+ 40 if (READ_ONCE(*theftp[t]) == THEFT_REQ)
41 pthread_kill(tid, SIGUSR1);
42 }
43 globalcount += *counterp[t];
44 *counterp[t] = 0;
45 globalreserve -= *countermaxp[t];
46 *countermaxp[t] = 0;
- 47 ACCESS_ONCE(*theftp[t]) = THEFT_IDLE;
+ 47 WRITE_ONCE(*theftp[t], THEFT_IDLE);
48 }
49 }
50
@@ -2907,16 +2907,16 @@ earlier examples.
5 counting = 1;
6 barrier();
7 if (countermax - counter >= delta &&
- 8 ACCESS_ONCE(theft) <= THEFT_REQ) {
+ 8 READ_ONCE(theft) <= THEFT_REQ) {
9 counter += delta;
10 fastpath = 1;
11 }
12 barrier();
13 counting = 0;
14 barrier();
- 15 if (ACCESS_ONCE(theft) == THEFT_ACK) {
+ 15 if (READ_ONCE(theft) == THEFT_ACK) {
16 smp_mb();
- 17 ACCESS_ONCE(theft) = THEFT_READY;
+ 17 WRITE_ONCE(theft, THEFT_READY);
18 }
19 if (fastpath)
20 return 1;
@@ -2954,16 +2954,16 @@ earlier examples.
42 counting = 1;
43 barrier();
44 if (counter >= delta &&
- 45 ACCESS_ONCE(theft) <= THEFT_REQ) {
+ 45 READ_ONCE(theft) <= THEFT_REQ) {
46 counter -= delta;
47 fastpath = 1;
48 }
49 barrier();
50 counting = 0;
51 barrier();
- 52 if (ACCESS_ONCE(theft) == THEFT_ACK) {
+ 52 if (READ_ONCE(theft) == THEFT_ACK) {
53 smp_mb();
- 54 ACCESS_ONCE(theft) = THEFT_READY;
+ 54 WRITE_ONCE(theft, THEFT_READY);
55 }
56 if (fastpath)
57 return 1;
--
2.7.4
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