perf-bench-futex: Add lock_pi stresser

PATCH New Davidlohr Bueso 2 participants 2 messages Jul 7, 2015 – Jul 21, 2015

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Davidlohr Bueso

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2015-07-07 08:56 UTC #0 lore raw

PATCH 1/1 perf-bench-futex: Add lock_pi stresser

Allows a way of measuring low level kernel implementation of FUTEX_LOCK_PI and FUTEX_UNLOCK_PI. The program comes in two flavors: (i) single futex (default), all threads contend on the same uaddr. For the sake of the benchmark, we call into kernel space even when the lock is uncontended. The kernel will set it to TID, any waters that come in and contend for the pi futex will be handled respectively by the kernel. (ii) -M option for multiple futexes, each thread deals with its own futex. This is a trivial scenario and only measures kernel handling of 0->TID transition.

Signed-off-by Davidlohr Bueso <[email protected]>

---
 tools/perf/Documentation/perf-bench.txt |   4 +
 tools/perf/bench/Build                  |   1 +
 tools/perf/bench/bench.h                |   2 +
 tools/perf/bench/futex-lock-pi.c        | 219 ++++++++++++++++++++++++++++++++
 tools/perf/bench/futex.h                |  20 +++
 tools/perf/builtin-bench.c              |   2 +
 6 files changed, 248 insertions(+)
 create mode 100644 tools/perf/bench/futex-lock-pi.c

tools/perf/Documentation/perf-bench.txt +4 -0

index bf3d064..ab632d9 100644
@@ -216,6 +216,10 @@ Suite for evaluating parallel wake calls.
 *requeue*::
 Suite for evaluating requeue calls.
 
+*lock-pi*::
+Suite for evaluating futex lock_pi calls.
+
+
 SEE ALSO
 --------
 linkperf:perf[1]

tools/perf/bench/Build +1 -0

index c3ab760..573e288 100644
@@ -5,6 +5,7 @@ perf-y += futex-hash.o
 perf-y += futex-wake.o
 perf-y += futex-wake-parallel.o
 perf-y += futex-requeue.o
+perf-y += futex-lock-pi.o
 
 perf-$(CONFIG_X86_64) += mem-memcpy-x86-64-asm.o
 perf-$(CONFIG_X86_64) += mem-memset-x86-64-asm.o

tools/perf/bench/bench.h +2 -0

index 70b2f71..a50df86 100644
@@ -36,6 +36,8 @@ extern int bench_futex_wake(int argc, const char **argv, const char *prefix);
 extern int bench_futex_wake_parallel(int argc, const char **argv,
 				     const char *prefix);
 extern int bench_futex_requeue(int argc, const char **argv, const char *prefix);
+/* pi futexes */
+extern int bench_futex_lock_pi(int argc, const char **argv, const char *prefix);
 
 #define BENCH_FORMAT_DEFAULT_STR	"default"
 #define BENCH_FORMAT_DEFAULT		0

tools/perf/bench/futex-lock-pi.c new file +219 -0

219 lines not on this page · raw message

tools/perf/bench/futex.h +20 -0

index 7ed22ff..d44de9f 100644
@@ -56,6 +56,26 @@ futex_wake(u_int32_t *uaddr, int nr_wake, int opflags)
 }
 
 /**
+ * futex_lock_pi() - block on uaddr as a PI mutex
+ * @detect:	whether (1) or not (0) to perform deadlock detection
+ */
+static inline int
+futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int detect,
+	      int opflags)
+{
+	return futex(uaddr, FUTEX_LOCK_PI, detect, timeout, NULL, 0, opflags);
+}
+
+/**
+ * futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter
+ */
+static inline int
+futex_unlock_pi(u_int32_t *uaddr, int opflags)
+{
+	return futex(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags);
+}
+
+/**
 * futex_cmp_requeue() - requeue tasks from uaddr to uaddr2
 * @nr_wake:        wake up to this many tasks
 * @nr_requeue:        requeue up to this many tasks

tools/perf/builtin-bench.c +2 -0

index b5314e4..f67934d 100644
@@ -60,6 +60,8 @@ static struct bench futex_benchmarks[] = {
 	{ "wake",	"Benchmark for futex wake calls",               bench_futex_wake	},
 	{ "wake-parallel", "Benchmark for parallel futex wake calls",   bench_futex_wake_parallel },
 	{ "requeue",	"Benchmark for futex requeue calls",            bench_futex_requeue	},
+	/* pi-futexes */
+	{ "lock-pi",	"Benchmark for futex lock_pi calls",            bench_futex_lock_pi	},
 	{ "all",	"Test all futex benchmarks",			NULL			},
 	{ NULL,		NULL,						NULL			}
 };

Signature · 1 line

2.1.4

tip-bot for Davidlohr Bueso

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2015-07-21 09:36 UTC #1 lore raw

[tip:perf/core] perf bench futex: Add lock_pi stresser

perf bench futex: Add lock_pi stresser

Commit-ID:  d2f3f5d2e9cae6e73f9642a5ddc8c8a07c35e79b
Gitweb:     http://git.kernel.org/tip/d2f3f5d2e9cae6e73f9642a5ddc8c8a07c35e79b
Author:     Davidlohr Bueso <[email protected]>
AuthorDate: Tue, 7 Jul 2015 01:55:53 -0700
Committer:  Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Mon, 20 Jul 2015 17:49:51 -0300

perf bench futex: Add lock_pi stresser

Allows a way of measuring low level kernel implementation of FUTEX_LOCK_PI and FUTEX_UNLOCK_PI.

The program comes in two flavors:

(i) single futex (default), all threads contend on the same uaddr. For the sake of the benchmark, we call into kernel space even when the lock is uncontended. The kernel will set it to TID, any waters that come in and contend for the pi futex will be handled respectively by the kernel.

(ii) -M option for multiple futexes, each thread deals with its own futex. This is a trivial scenario and only measures kernel handling of 0->TID transition.

Signed-off-by Davidlohr Bueso <[email protected]>

Cc Mel Gorman <[email protected]>

Link http://lkml.kernel.org/r/[email protected] open here

Signed-off-by Arnaldo Carvalho de Melo <[email protected]>

---
 tools/perf/Documentation/perf-bench.txt            |   4 +
 tools/perf/bench/Build                             |   1 +
 tools/perf/bench/bench.h                           |   2 +
 tools/perf/bench/{futex-hash.c => futex-lock-pi.c} | 202 +++++++++++----------
 tools/perf/bench/futex.h                           |  20 ++
 tools/perf/builtin-bench.c                         |   2 +
 6 files changed, 132 insertions(+), 99 deletions(-)

tools/perf/Documentation/perf-bench.txt +4 -0

index bf3d064..ab632d9 100644
@@ -216,6 +216,10 @@ Suite for evaluating parallel wake calls.
 *requeue*::
 Suite for evaluating requeue calls.
 
+*lock-pi*::
+Suite for evaluating futex lock_pi calls.
+
+
 SEE ALSO
 --------
 linkperf:perf[1]

tools/perf/bench/Build +1 -0

index c3ab760..573e288 100644
@@ -5,6 +5,7 @@ perf-y += futex-hash.o
 perf-y += futex-wake.o
 perf-y += futex-wake-parallel.o
 perf-y += futex-requeue.o
+perf-y += futex-lock-pi.o
 
 perf-$(CONFIG_X86_64) += mem-memcpy-x86-64-asm.o
 perf-$(CONFIG_X86_64) += mem-memset-x86-64-asm.o

tools/perf/bench/bench.h +2 -0

index 70b2f71..a50df86 100644
@@ -36,6 +36,8 @@ extern int bench_futex_wake(int argc, const char **argv, const char *prefix);
 extern int bench_futex_wake_parallel(int argc, const char **argv,
 				     const char *prefix);
 extern int bench_futex_requeue(int argc, const char **argv, const char *prefix);
+/* pi futexes */
+extern int bench_futex_lock_pi(int argc, const char **argv, const char *prefix);
 
 #define BENCH_FORMAT_DEFAULT_STR	"default"
 #define BENCH_FORMAT_DEFAULT		0

tools/perf/bench/futex-lock-pi.c renamed from tools/perf/bench/futex-hash.c +103 ~~-99~~

282 lines not on this page · raw message

tools/perf/bench/futex.h +20 -0

index 7ed22ff..d44de9f 100644
@@ -56,6 +56,26 @@ futex_wake(u_int32_t *uaddr, int nr_wake, int opflags)
 }
 
 /**
+ * futex_lock_pi() - block on uaddr as a PI mutex
+ * @detect:	whether (1) or not (0) to perform deadlock detection
+ */
+static inline int
+futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int detect,
+	      int opflags)
+{
+	return futex(uaddr, FUTEX_LOCK_PI, detect, timeout, NULL, 0, opflags);
+}
+
+/**
+ * futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter
+ */
+static inline int
+futex_unlock_pi(u_int32_t *uaddr, int opflags)
+{
+	return futex(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags);
+}
+
+/**
 * futex_cmp_requeue() - requeue tasks from uaddr to uaddr2
 * @nr_wake:        wake up to this many tasks
 * @nr_requeue:        requeue up to this many tasks

tools/perf/builtin-bench.c +2 -0

index b5314e4..f67934d 100644
@@ -60,6 +60,8 @@ static struct bench futex_benchmarks[] = {
 	{ "wake",	"Benchmark for futex wake calls",               bench_futex_wake	},
 	{ "wake-parallel", "Benchmark for parallel futex wake calls",   bench_futex_wake_parallel },
 	{ "requeue",	"Benchmark for futex requeue calls",            bench_futex_requeue	},
+	/* pi-futexes */
+	{ "lock-pi",	"Benchmark for futex lock_pi calls",            bench_futex_lock_pi	},
 	{ "all",	"Test all futex benchmarks",			NULL			},
 	{ NULL,		NULL,						NULL			}
 };