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[PATCH v6 00/21] tracing: probeevent: Improve fetcharg features

by Masami Hiramatsu

Hi, This is the 6th version of the fetch-arg improvement series. This includes variable changes on fetcharg framework like, - Add fetcharg testcases (syntax, argN, symbol, string and array) and probepoint testcase. - Rewrite fetcharg framework with fetch_insn, switch-case based instead of function pointer. - Add "symbol" type support, which shows symbol+offset instead of address value. - Add "$argN" fetcharg, which fetches function parameters. (currently only for x86-64) - Add array type support (including string arrary :) ) , which enables to get fixed length array from probe-events. - Add array type support for perf-probe, so that user can dump partial array entries. V5 is here: https://lkml.org/lkml/2018/3/12/558 Changes from the v5 is here: - [16/21] Fix README to add backslash escapes to "[]" - [20/21] Add a bugfix patch for perf-probe. - [21/21] Add array type support for perf-probe. Note that [20/21] is same as https://lkml.org/lkml/2018/3/16/108 I have to add this because the last patch depends on it. Anyway, [20/21] and [21/21] is only for showing how perf-probe will enhanced by this series. So those are extra work. I will resend thodr again after [01/21]-[19/21] are merged. Here are examples: o 'symbol' type # echo 'p vfs_read $stack0:symbol' > kprobe_events # echo 1 > events/kprobes/p_vfs_read_0/enable # tail -n 3 trace sh-729 [007] ...2 105.753637: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=SyS_read+0x42/0x90 tail-736 [000] ...2 105.754904: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=kernel_read+0x2c/0x40 tail-736 [000] ...2 105.754929: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=kernel_read+0x2c/0x40 o $argN # echo 'p vfs_read $arg0 $arg1 $arg2' > kprobe_events # echo 1 > events/kprobes/p_vfs_read_0/enable # tail -n 3 trace sh-726 [007] ...2 134.288973: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=0xffff88001d98ec00 arg2=0x7ffeb4330f79 arg3=0x1 tail-731 [000] ...2 134.289987: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=0xffff88001d9dd200 arg2=0xffff88001d8a0a00 arg3=0x80 tail-731 [000] ...2 134.290016: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=0xffff88001d9dd200 arg2=0xffff88001faf4a00 arg3=0x150 o Array type # echo 'p vfs_read +0($stack):x64 +0($stack):x8[8]' > kprobe_events # echo 1 > events/kprobes/p_vfs_read_0/enable # tail -n 3 trace sh-729 [007] ...2 91.701664: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=0xffffffff811b1252 arg2={0x52,0x12,0x1b,0x81,0xff,0xff,0xff,0xff} tail-734 [000] ...2 91.702366: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=0xffffffff811b0dec arg2={0xec,0xd,0x1b,0x81,0xff,0xff,0xff,0xff} tail-734 [000] ...2 91.702386: p_vfs_read_0: (vfs_read+0x0/0x130) arg1=0xffffffff811b0dec arg2={0xec,0xd,0x1b,0x81,0xff,0xff,0xff,0xff} # # cat events/kprobes/p_vfs_read_0/format name: p_vfs_read_0 ID: 1069 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:unsigned long __probe_ip; offset:8; size:8; signed:0; field:u64 arg1; offset:16; size:0; signed:0; field:u8 arg2[8]; offset:24; size:8; signed:0; print fmt: "(%lx) arg1=0x%Lx arg2={0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x}", REC->__probe_ip, REC->arg1, REC->arg2[0], REC->arg2[1], REC->arg2[2], REC->arg2[3], REC->arg2[4], REC->arg2[5], REC->arg2[6], REC->arg2[7] o String Array type # echo "p create_trace_kprobe arg1=+0(%si):string[3]" > kprobe_events # echo test1 test2 test3 >> kprobe_events sh: write error: Invalid argument # echo 'p vfs_read $stack' >> kprobe_events # tail -n 2 trace sh-744 [007] ...1 183.382407: p_create_trace_kprobe_0: (create_trace_kprobe+0x0/0x890) arg1={"test1","test2","test3"} sh-744 [007] ...1 230.487809: p_create_trace_kprobe_0: (create_trace_kprobe+0x0/0x890) arg1={"p","vfs_read","$stack"} Thank you, --- Masami Hiramatsu (21): [BUGFIX] tracing: probeevent: Fix to support minus offset from symbol selftests: ftrace: Add probe event argument syntax testcase selftests: ftrace: Add a testcase for string type with kprobe_event selftests: ftrace: Add a testcase for probepoint tracing: probeevent: Cleanup print argument functions tracing: probeevent: Cleanup argument field definition tracing: probeevent: Remove NOKPROBE_SYMBOL from print functions tracing: probeevent: Introduce new argument fetching code tracing: probeevent: Unify fetch type tables tracing: probeevent: Return consumed bytes of dynamic area tracing: probeevent: Append traceprobe_ for exported function tracing: probeevent: Unify fetch_insn processing common part tracing: probeevent: Add symbol type x86: ptrace: Add function argument access API tracing: probeevent: Add $argN for accessing function args tracing: probeevent: Add array type support selftests: ftrace: Add a testcase for symbol type selftests: ftrace: Add a testcase for $argN with kprobe_event selftests: ftrace: Add a testcase for array type with kprobe_event [RESEND] perf-probe: Fix to convert array type collectly perf-probe: Add array argument support Documentation/trace/kprobetrace.txt | 26 + arch/Kconfig | 7 arch/x86/Kconfig | 1 arch/x86/include/asm/ptrace.h | 38 + kernel/trace/trace.c | 9 kernel/trace/trace_kprobe.c | 366 ++++-------- kernel/trace/trace_probe.c | 628 +++++++++----------- kernel/trace/trace_probe.h | 284 +++------ kernel/trace/trace_probe_tmpl.h | 214 +++++++ kernel/trace/trace_uprobe.c | 168 ++--- tools/perf/Documentation/perf-probe.txt | 2 tools/perf/util/probe-event.c | 20 + tools/perf/util/probe-event.h | 2 tools/perf/util/probe-file.c | 5 tools/perf/util/probe-file.h | 1 tools/perf/util/probe-finder.c | 108 ++- .../ftrace/test.d/kprobe/kprobe_args_argN.tc | 25 + .../ftrace/test.d/kprobe/kprobe_args_array.tc | 92 +++ .../ftrace/test.d/kprobe/kprobe_args_string.tc | 46 + .../ftrace/test.d/kprobe/kprobe_args_symbol.tc | 77 ++ .../ftrace/test.d/kprobe/kprobe_args_syntax.tc | 97 +++ .../selftests/ftrace/test.d/kprobe/probepoint.tc | 43 + 22 files changed, 1319 insertions(+), 940 deletions(-) create mode 100644 kernel/trace/trace_probe_tmpl.h create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_argN.tc create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_array.tc create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_symbol.tc create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_syntax.tc create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/probepoint.tc -- Masami Hiramatsu (Linaro) <mhiramat(a)kernel.org> -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

3
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[PATCH] selftests/ftrace: fix spelling mistake: "tiggers" -> "triggers"

by Colin King

From: Colin Ian King <colin.king(a)canonical.com> Trivial fix to spelling mistake in message text Signed-off-by: Colin Ian King <colin.king(a)canonical.com> --- tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc index c5ef8b9d02b3..1b8faf4c318c 100644 --- a/tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc +++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc @@ -35,7 +35,7 @@ do_reset reset_trigger -echo "Test histogram multiple tiggers" +echo "Test histogram multiple triggers" echo 'hist:keys=parent_pid:vals=child_pid' > events/sched/sched_process_fork/trigger echo 'hist:keys=parent_comm:vals=child_pid' >> events/sched/sched_process_fork/trigger -- 2.15.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

7
9
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[PATCH v12 00/22] selftests, powerpc, x86 : Memory Protection Keys

by Ram Pai

Memory protection keys enables an application to protect its address space from inadvertent access by its own code. This feature is now enabled on powerpc architecture and integrated in 4.16-rc1. The patches move the selftests to arch neutral directory and enhance their test coverage. Test ---- Verified for correctness on powerpc and on x86 architectures(using EC2 ubuntu VM instance). History: ------- version 12: (1) fixed the offset of pkey field in the siginfo structure for x86_64 and powerpc. And tries to use the actual field if the headers have it defined. version 11: (1) fixed a deadlock in the ptrace testcase. version 10 and prior: (1) moved the testcase to arch neutral directory (2) split the changes into incremental patches. Ram Pai (21): selftests/x86: Move protecton key selftest to arch neutral directory selftests/vm: rename all references to pkru to a generic name selftests/vm: move generic definitions to header file selftests/vm: typecast the pkey register selftests/vm: generic function to handle shadow key register selftests/vm: fix the wrong assert in pkey_disable_set() selftests/vm: fixed bugs in pkey_disable_clear() selftests/vm: clear the bits in shadow reg when a pkey is freed. selftests/vm: fix alloc_random_pkey() to make it really random selftests/vm: introduce two arch independent abstraction selftests/vm: pkey register should match shadow pkey selftests/vm: generic cleanup selftests/vm: powerpc implementation for generic abstraction selftests/vm: clear the bits in shadow reg when a pkey is freed. selftests/vm: powerpc implementation to check support for pkey selftests/vm: fix an assertion in test_pkey_alloc_exhaust() selftests/vm: associate key on a mapped page and detect access violation selftests/vm: associate key on a mapped page and detect write violation selftests/vm: detect write violation on a mapped access-denied-key page selftests/vm: testcases must restore pkey-permissions selftests/vm: sub-page allocator Thiago Jung Bauermann (1): selftests/vm: Fix deadlock in protection_keys.c tools/testing/selftests/vm/Makefile | 1 + tools/testing/selftests/vm/pkey-helpers.h | 434 ++++++++ tools/testing/selftests/vm/protection_keys.c | 1471 +++++++++++++++++++++++++ tools/testing/selftests/x86/Makefile | 2 +- tools/testing/selftests/x86/pkey-helpers.h | 223 ---- tools/testing/selftests/x86/protection_keys.c | 1407 ----------------------- 6 files changed, 1907 insertions(+), 1631 deletions(-) create mode 100644 tools/testing/selftests/vm/pkey-helpers.h create mode 100644 tools/testing/selftests/vm/protection_keys.c delete mode 100644 tools/testing/selftests/x86/pkey-helpers.h delete mode 100644 tools/testing/selftests/x86/protection_keys.c -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

5
48
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[PATCH v2 0/4] selftests: fix compiling issues

by changbin.du＠intel.com

From: Changbin Du <changbin.du(a)intel.com> These 4 patches fixed all the existing compiling errors. With this serias, no compiling error reported after running 'make kselftest'. v2: resolve compiling error if run make in individual folder. Changbin Du (4): selftests/Makefile: append a slash to env variable OUTPUT selftests/gpio: fix paths in Makefile kselftest: install sanitized kernel headers before compiling selftests/bpf: fix compiling errors tools/testing/selftests/.gitignore | 4 ---- tools/testing/selftests/Makefile | 21 ++++++++++++--------- tools/testing/selftests/bpf/Makefile | 5 +++-- tools/testing/selftests/gpio/.gitignore | 4 ++++ tools/testing/selftests/gpio/Makefile | 17 +++++++++-------- 5 files changed, 28 insertions(+), 23 deletions(-) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

3
7
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[PATCH 4.15 084/105] selftests/x86/ptrace_syscall: Fix for yet more glibc interference

by Greg Kroah-Hartman

4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski <luto(a)kernel.org> commit 4b0b37d4cc54b21a6ecad7271cbc850555869c62 upstream. glibc keeps getting cleverer, and my version now turns raise() into more than one syscall. Since the test relies on ptrace seeing an exact set of syscalls, this breaks the test. Replace raise(SIGSTOP) with syscall(SYS_tgkill, ...) to force glibc to get out of our way. Signed-off-by: Andy Lutomirski <luto(a)kernel.org> Cc: Borislav Petkov <bp(a)alien8.de> Cc: Linus Torvalds <torvalds(a)linux-foundation.org> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Thomas Gleixner <tglx(a)linutronix.de> Cc: linux-kselftest(a)vger.kernel.org Cc: stable(a)vger.kernel.org Link: http://lkml.kernel.org/r/bc80338b453afa187bc5f895bd8e2c8d6e264da2.152130027… Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- tools/testing/selftests/x86/ptrace_syscall.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/tools/testing/selftests/x86/ptrace_syscall.c +++ b/tools/testing/selftests/x86/ptrace_syscall.c @@ -183,8 +183,10 @@ static void test_ptrace_syscall_restart( if (ptrace(PTRACE_TRACEME, 0, 0, 0) != 0) err(1, "PTRACE_TRACEME"); + pid_t pid = getpid(), tid = syscall(SYS_gettid); + printf("\tChild will make one syscall\n"); - raise(SIGSTOP); + syscall(SYS_tgkill, pid, tid, SIGSTOP); syscall(SYS_gettid, 10, 11, 12, 13, 14, 15); _exit(0); @@ -301,9 +303,11 @@ static void test_restart_under_ptrace(vo if (ptrace(PTRACE_TRACEME, 0, 0, 0) != 0) err(1, "PTRACE_TRACEME"); + pid_t pid = getpid(), tid = syscall(SYS_gettid); + printf("\tChild will take a nap until signaled\n"); setsigign(SIGUSR1, SA_RESTART); - raise(SIGSTOP); + syscall(SYS_tgkill, pid, tid, SIGSTOP); syscall(SYS_pause, 0, 0, 0, 0, 0, 0); _exit(0); -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

1
0
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[PATCH 4.14 079/101] selftests/x86/ptrace_syscall: Fix for yet more glibc interference

by Greg Kroah-Hartman

4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski <luto(a)kernel.org> commit 4b0b37d4cc54b21a6ecad7271cbc850555869c62 upstream. glibc keeps getting cleverer, and my version now turns raise() into more than one syscall. Since the test relies on ptrace seeing an exact set of syscalls, this breaks the test. Replace raise(SIGSTOP) with syscall(SYS_tgkill, ...) to force glibc to get out of our way. Signed-off-by: Andy Lutomirski <luto(a)kernel.org> Cc: Borislav Petkov <bp(a)alien8.de> Cc: Linus Torvalds <torvalds(a)linux-foundation.org> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Thomas Gleixner <tglx(a)linutronix.de> Cc: linux-kselftest(a)vger.kernel.org Cc: stable(a)vger.kernel.org Link: http://lkml.kernel.org/r/bc80338b453afa187bc5f895bd8e2c8d6e264da2.152130027… Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- tools/testing/selftests/x86/ptrace_syscall.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/tools/testing/selftests/x86/ptrace_syscall.c +++ b/tools/testing/selftests/x86/ptrace_syscall.c @@ -183,8 +183,10 @@ static void test_ptrace_syscall_restart( if (ptrace(PTRACE_TRACEME, 0, 0, 0) != 0) err(1, "PTRACE_TRACEME"); + pid_t pid = getpid(), tid = syscall(SYS_gettid); + printf("\tChild will make one syscall\n"); - raise(SIGSTOP); + syscall(SYS_tgkill, pid, tid, SIGSTOP); syscall(SYS_gettid, 10, 11, 12, 13, 14, 15); _exit(0); @@ -301,9 +303,11 @@ static void test_restart_under_ptrace(vo if (ptrace(PTRACE_TRACEME, 0, 0, 0) != 0) err(1, "PTRACE_TRACEME"); + pid_t pid = getpid(), tid = syscall(SYS_gettid); + printf("\tChild will take a nap until signaled\n"); setsigign(SIGUSR1, SA_RESTART); - raise(SIGSTOP); + syscall(SYS_tgkill, pid, tid, SIGSTOP); syscall(SYS_pause, 0, 0, 0, 0, 0, 0); _exit(0); -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

1
0
0 0

[PATCH 4.9 49/67] selftests/x86/ptrace_syscall: Fix for yet more glibc interference

by Greg Kroah-Hartman

4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski <luto(a)kernel.org> commit 4b0b37d4cc54b21a6ecad7271cbc850555869c62 upstream. glibc keeps getting cleverer, and my version now turns raise() into more than one syscall. Since the test relies on ptrace seeing an exact set of syscalls, this breaks the test. Replace raise(SIGSTOP) with syscall(SYS_tgkill, ...) to force glibc to get out of our way. Signed-off-by: Andy Lutomirski <luto(a)kernel.org> Cc: Borislav Petkov <bp(a)alien8.de> Cc: Linus Torvalds <torvalds(a)linux-foundation.org> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Thomas Gleixner <tglx(a)linutronix.de> Cc: linux-kselftest(a)vger.kernel.org Cc: stable(a)vger.kernel.org Link: http://lkml.kernel.org/r/bc80338b453afa187bc5f895bd8e2c8d6e264da2.152130027… Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- tools/testing/selftests/x86/ptrace_syscall.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/tools/testing/selftests/x86/ptrace_syscall.c +++ b/tools/testing/selftests/x86/ptrace_syscall.c @@ -182,8 +182,10 @@ static void test_ptrace_syscall_restart( if (ptrace(PTRACE_TRACEME, 0, 0, 0) != 0) err(1, "PTRACE_TRACEME"); + pid_t pid = getpid(), tid = syscall(SYS_gettid); + printf("\tChild will make one syscall\n"); - raise(SIGSTOP); + syscall(SYS_tgkill, pid, tid, SIGSTOP); syscall(SYS_gettid, 10, 11, 12, 13, 14, 15); _exit(0); @@ -300,9 +302,11 @@ static void test_restart_under_ptrace(vo if (ptrace(PTRACE_TRACEME, 0, 0, 0) != 0) err(1, "PTRACE_TRACEME"); + pid_t pid = getpid(), tid = syscall(SYS_gettid); + printf("\tChild will take a nap until signaled\n"); setsigign(SIGUSR1, SA_RESTART); - raise(SIGSTOP); + syscall(SYS_tgkill, pid, tid, SIGSTOP); syscall(SYS_pause, 0, 0, 0, 0, 0, 0); _exit(0); -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

1
0
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[RFC PATCH for 4.17 21/21] rseq: selftests: Provide Makefile, scripts, gitignore

by Mathieu Desnoyers

A run_param_test.sh script runs many variants of the parametrizable tests. Wire up the rseq Makefile, add directory entry into MAINTAINERS file. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> CC: Shuah Khan <shuahkh(a)osg.samsung.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Paul Turner <pjt(a)google.com> CC: Andrew Hunter <ahh(a)google.com> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andi Kleen <andi(a)firstfloor.org> CC: Dave Watson <davejwatson(a)fb.com> CC: Chris Lameter <cl(a)linux.com> CC: Ingo Molnar <mingo(a)redhat.com> CC: "H. Peter Anvin" <hpa(a)zytor.com> CC: Ben Maurer <bmaurer(a)fb.com> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: "Paul E. McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: linux-kselftest(a)vger.kernel.org CC: linux-api(a)vger.kernel.org --- MAINTAINERS | 1 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/rseq/.gitignore | 7 ++ tools/testing/selftests/rseq/Makefile | 37 +++++++ tools/testing/selftests/rseq/run_param_test.sh | 130 +++++++++++++++++++++++++ 5 files changed, 176 insertions(+) create mode 100644 tools/testing/selftests/rseq/.gitignore create mode 100644 tools/testing/selftests/rseq/Makefile create mode 100755 tools/testing/selftests/rseq/run_param_test.sh diff --git a/MAINTAINERS b/MAINTAINERS index 936ff672d5fb..ba630a386a88 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -11830,6 +11830,7 @@ S: Supported F: kernel/rseq.c F: include/uapi/linux/rseq.h F: include/trace/events/rseq.h +F: tools/testing/selftests/rseq/ RFKILL M: Johannes Berg <johannes(a)sipsolutions.net> diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 1322e63f5963..c1c9323d4e50 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -26,6 +26,7 @@ TARGETS += nsfs TARGETS += powerpc TARGETS += pstore TARGETS += ptrace +TARGETS += rseq TARGETS += seccomp TARGETS += sigaltstack TARGETS += size diff --git a/tools/testing/selftests/rseq/.gitignore b/tools/testing/selftests/rseq/.gitignore new file mode 100644 index 000000000000..73dcf05b69fd --- /dev/null +++ b/tools/testing/selftests/rseq/.gitignore @@ -0,0 +1,7 @@ +basic_percpu_ops_test +basic_test +basic_rseq_op_test +param_test +param_test_benchmark +param_test_compare_twice +param_test_skip_fastpath diff --git a/tools/testing/selftests/rseq/Makefile b/tools/testing/selftests/rseq/Makefile new file mode 100644 index 000000000000..69f90d718774 --- /dev/null +++ b/tools/testing/selftests/rseq/Makefile @@ -0,0 +1,37 @@ +CFLAGS += -O2 -Wall -g -I./ -I../cpu-opv/ -I../../../../usr/include/ -L./ -Wl,-rpath=./ +LDLIBS += -lpthread + +# Own dependencies because we only want to build against 1st prerequisite, but +# still track changes to header files and depend on shared object. +OVERRIDE_TARGETS = 1 + +TEST_GEN_PROGS = basic_test basic_percpu_ops_test \ + param_test param_test_skip_fastpath \ + param_test_benchmark param_test_compare_twice + +TEST_GEN_PROGS_EXTENDED = librseq.so libcpu-op.so + +TEST_PROGS = run_param_test.sh + +include ../lib.mk + +$(OUTPUT)/librseq.so: rseq.c rseq.h rseq-*.h + $(CC) $(CFLAGS) -shared -fPIC $< $(LDLIBS) -o $@ + +$(OUTPUT)/libcpu-op.so: ../cpu-opv/cpu-op.c ../cpu-opv/cpu-op.h + $(CC) $(CFLAGS) -shared -fPIC $< $(LDLIBS) -o $@ + +$(OUTPUT)/%: %.c $(TEST_GEN_PROGS_EXTENDED) rseq.h rseq-*.h ../cpu-opv/cpu-op.h percpu-op.h + $(CC) $(CFLAGS) $< $(LDLIBS) -lrseq -lcpu-op -o $@ + +$(OUTPUT)/param_test_skip_fastpath: param_test.c $(TEST_GEN_PROGS_EXTENDED) \ + rseq.h rseq-*.h ../cpu-opv/cpu-op.h percpu-op.h + $(CC) $(CFLAGS) -DRSEQ_SKIP_FASTPATH $< $(LDLIBS) -lrseq -lcpu-op -o $@ + +$(OUTPUT)/param_test_benchmark: param_test.c $(TEST_GEN_PROGS_EXTENDED) \ + rseq.h rseq-*.h ../cpu-opv/cpu-op.h percpu-op.h + $(CC) $(CFLAGS) -DBENCHMARK $< $(LDLIBS) -lrseq -lcpu-op -o $@ + +$(OUTPUT)/param_test_compare_twice: param_test.c $(TEST_GEN_PROGS_EXTENDED) \ + rseq.h rseq-*.h ../cpu-opv/cpu-op.h percpu-op.h + $(CC) $(CFLAGS) -DRSEQ_COMPARE_TWICE $< $(LDLIBS) -lrseq -lcpu-op -o $@ diff --git a/tools/testing/selftests/rseq/run_param_test.sh b/tools/testing/selftests/rseq/run_param_test.sh new file mode 100755 index 000000000000..64d4c7d722c9 --- /dev/null +++ b/tools/testing/selftests/rseq/run_param_test.sh @@ -0,0 +1,130 @@ +#!/bin/bash + +EXTRA_ARGS=${@} + +OLDIFS="$IFS" +IFS=$'\n' +TEST_LIST=( + "-T s" + "-T l" + "-T b" + "-T b -M" + "-T m" + "-T m -M" + "-T i" +) + +TEST_NAME=( + "spinlock" + "list" + "buffer" + "buffer with barrier" + "memcpy" + "memcpy with barrier" + "increment" +) +IFS="$OLDIFS" + +REPS=1000 + +function do_tests() +{ + local i=0 + while [ "$i" -lt "${#TEST_LIST[@]}" ]; do + echo "Running test ${TEST_NAME[$i]}" + ./param_test ${TEST_LIST[$i]} -r ${REPS} ${@} ${EXTRA_ARGS} || exit 1 + echo "Running skip fast-path test ${TEST_NAME[$i]}" + ./param_test_skip_fastpath ${TEST_LIST[$i]} -r ${REPS} ${@} ${EXTRA_ARGS} || exit 1 + echo "Running compare-twice test ${TEST_NAME[$i]}" + ./param_test_compare_twice ${TEST_LIST[$i]} -r ${REPS} ${@} ${EXTRA_ARGS} || exit 1 + let "i++" + done +} + +echo "Default parameters" +do_tests + +echo "Loop injection: 10000 loops" + +OLDIFS="$IFS" +IFS=$'\n' +INJECT_LIST=( + "1" + "2" + "3" + "4" + "5" + "6" + "7" + "8" + "9" +) +IFS="$OLDIFS" + +NR_LOOPS=10000 + +i=0 +while [ "$i" -lt "${#INJECT_LIST[@]}" ]; do + echo "Injecting at <${INJECT_LIST[$i]}>" + do_tests -${INJECT_LIST[i]} ${NR_LOOPS} + let "i++" +done +NR_LOOPS= + +function inject_blocking() +{ + OLDIFS="$IFS" + IFS=$'\n' + INJECT_LIST=( + "7" + "8" + "9" + ) + IFS="$OLDIFS" + + NR_LOOPS=-1 + + i=0 + while [ "$i" -lt "${#INJECT_LIST[@]}" ]; do + echo "Injecting at <${INJECT_LIST[$i]}>" + do_tests -${INJECT_LIST[i]} -1 ${@} + let "i++" + done + NR_LOOPS= +} + +echo "Yield injection (25%)" +inject_blocking -m 4 -y + +echo "Yield injection (50%)" +inject_blocking -m 2 -y + +echo "Yield injection (100%)" +inject_blocking -m 1 -y + +echo "Kill injection (25%)" +inject_blocking -m 4 -k + +echo "Kill injection (50%)" +inject_blocking -m 2 -k + +echo "Kill injection (100%)" +inject_blocking -m 1 -k + +echo "Sleep injection (1ms, 25%)" +inject_blocking -m 4 -s 1 + +echo "Sleep injection (1ms, 50%)" +inject_blocking -m 2 -s 1 + +echo "Sleep injection (1ms, 100%)" +inject_blocking -m 1 -s 1 + +echo "Disable rseq for 25% threads" +do_tests -D 4 + +echo "Disable rseq for 50% threads" +do_tests -D 2 + +echo "Disable rseq" +do_tests -d -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

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[RFC PATCH for 4.17 20/21] rseq: selftests: Provide parametrized tests

by Mathieu Desnoyers

"param_test" is a parametrizable restartable sequences test. See the "--help" output for usage. "param_test_benchmark" is the same as "param_test", but it removes testing book-keeping code to allow accurate benchmarks. "param_test_skip_fastpath" is the same as "param_test", but it skips the rseq fast-path, and only calls the cpu_opv slow path. "param_test_compare_twice" is the same as "param_test", but it performs each comparison within rseq critical section twice, thus validating invariants. If any of the second comparisons fails, an error message is printed and the test aborts. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> CC: Shuah Khan <shuahkh(a)osg.samsung.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Paul Turner <pjt(a)google.com> CC: Andrew Hunter <ahh(a)google.com> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andi Kleen <andi(a)firstfloor.org> CC: Dave Watson <davejwatson(a)fb.com> CC: Chris Lameter <cl(a)linux.com> CC: Ingo Molnar <mingo(a)redhat.com> CC: "H. Peter Anvin" <hpa(a)zytor.com> CC: Ben Maurer <bmaurer(a)fb.com> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: "Paul E. McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: linux-kselftest(a)vger.kernel.org CC: linux-api(a)vger.kernel.org --- tools/testing/selftests/rseq/param_test.c | 1163 +++++++++++++++++++++++++++++ 1 file changed, 1163 insertions(+) create mode 100644 tools/testing/selftests/rseq/param_test.c diff --git a/tools/testing/selftests/rseq/param_test.c b/tools/testing/selftests/rseq/param_test.c new file mode 100644 index 000000000000..0a7c05f506be --- /dev/null +++ b/tools/testing/selftests/rseq/param_test.c @@ -0,0 +1,1163 @@ +#define _GNU_SOURCE +#include <assert.h> +#include <pthread.h> +#include <sched.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <syscall.h> +#include <unistd.h> +#include <poll.h> +#include <sys/types.h> +#include <signal.h> +#include <errno.h> +#include <stddef.h> + +static inline pid_t gettid(void) +{ + return syscall(__NR_gettid); +} + +#define NR_INJECT 9 +static int loop_cnt[NR_INJECT + 1]; + +static int loop_cnt_1 asm("asm_loop_cnt_1") __attribute__((used)); +static int loop_cnt_2 asm("asm_loop_cnt_2") __attribute__((used)); +static int loop_cnt_3 asm("asm_loop_cnt_3") __attribute__((used)); +static int loop_cnt_4 asm("asm_loop_cnt_4") __attribute__((used)); +static int loop_cnt_5 asm("asm_loop_cnt_5") __attribute__((used)); +static int loop_cnt_6 asm("asm_loop_cnt_6") __attribute__((used)); + +static int opt_modulo, verbose; + +static int opt_yield, opt_signal, opt_sleep, + opt_disable_rseq, opt_threads = 200, + opt_disable_mod = 0, opt_test = 's', opt_mb = 0; + +static long long opt_reps = 5000; + +static __thread __attribute__((tls_model("initial-exec"))) +unsigned int signals_delivered; + +#ifndef BENCHMARK + +static __thread __attribute__((tls_model("initial-exec"), unused)) +unsigned int yield_mod_cnt, nr_abort; + +#define printf_verbose(fmt, ...) \ + do { \ + if (verbose) \ + printf(fmt, ## __VA_ARGS__); \ + } while (0) + +#if defined(__x86_64__) || defined(__i386__) + +#define INJECT_ASM_REG "eax" + +#define RSEQ_INJECT_CLOBBER \ + , INJECT_ASM_REG + +#define RSEQ_INJECT_ASM(n) \ + "mov asm_loop_cnt_" #n ", %%" INJECT_ASM_REG "\n\t" \ + "test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "dec %%" INJECT_ASM_REG "\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" + +#elif defined(__ARMEL__) + +#define RSEQ_INJECT_INPUT \ + , [loop_cnt_1]"m"(loop_cnt[1]) \ + , [loop_cnt_2]"m"(loop_cnt[2]) \ + , [loop_cnt_3]"m"(loop_cnt[3]) \ + , [loop_cnt_4]"m"(loop_cnt[4]) \ + , [loop_cnt_5]"m"(loop_cnt[5]) \ + , [loop_cnt_6]"m"(loop_cnt[6]) + +#define INJECT_ASM_REG "r4" + +#define RSEQ_INJECT_CLOBBER \ + , INJECT_ASM_REG + +#define RSEQ_INJECT_ASM(n) \ + "ldr " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \ + "cmp " INJECT_ASM_REG ", #0\n\t" \ + "beq 333f\n\t" \ + "222:\n\t" \ + "subs " INJECT_ASM_REG ", #1\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" + +#elif __PPC__ + +#define RSEQ_INJECT_INPUT \ + , [loop_cnt_1]"m"(loop_cnt[1]) \ + , [loop_cnt_2]"m"(loop_cnt[2]) \ + , [loop_cnt_3]"m"(loop_cnt[3]) \ + , [loop_cnt_4]"m"(loop_cnt[4]) \ + , [loop_cnt_5]"m"(loop_cnt[5]) \ + , [loop_cnt_6]"m"(loop_cnt[6]) + +#define INJECT_ASM_REG "r18" + +#define RSEQ_INJECT_CLOBBER \ + , INJECT_ASM_REG + +#define RSEQ_INJECT_ASM(n) \ + "lwz %%" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \ + "cmpwi %%" INJECT_ASM_REG ", 0\n\t" \ + "beq 333f\n\t" \ + "222:\n\t" \ + "subic. %%" INJECT_ASM_REG ", %%" INJECT_ASM_REG ", 1\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" +#else +#error unsupported target +#endif + +#define RSEQ_INJECT_FAILED \ + nr_abort++; + +#define RSEQ_INJECT_C(n) \ +{ \ + int loc_i, loc_nr_loops = loop_cnt[n]; \ + \ + for (loc_i = 0; loc_i < loc_nr_loops; loc_i++) { \ + rseq_barrier(); \ + } \ + if (loc_nr_loops == -1 && opt_modulo) { \ + if (yield_mod_cnt == opt_modulo - 1) { \ + if (opt_sleep > 0) \ + poll(NULL, 0, opt_sleep); \ + if (opt_yield) \ + sched_yield(); \ + if (opt_signal) \ + raise(SIGUSR1); \ + yield_mod_cnt = 0; \ + } else { \ + yield_mod_cnt++; \ + } \ + } \ +} + +#else + +#define printf_verbose(fmt, ...) + +#endif /* BENCHMARK */ + +#include "percpu-op.h" + +struct percpu_lock_entry { + intptr_t v; +} __attribute__((aligned(128))); + +struct percpu_lock { + struct percpu_lock_entry c[CPU_SETSIZE]; +}; + +struct test_data_entry { + intptr_t count; +} __attribute__((aligned(128))); + +struct spinlock_test_data { + struct percpu_lock lock; + struct test_data_entry c[CPU_SETSIZE]; +}; + +struct spinlock_thread_test_data { + struct spinlock_test_data *data; + long long reps; + int reg; +}; + +struct inc_test_data { + struct test_data_entry c[CPU_SETSIZE]; +}; + +struct inc_thread_test_data { + struct inc_test_data *data; + long long reps; + int reg; +}; + +struct percpu_list_node { + intptr_t data; + struct percpu_list_node *next; +}; + +struct percpu_list_entry { + struct percpu_list_node *head; +} __attribute__((aligned(128))); + +struct percpu_list { + struct percpu_list_entry c[CPU_SETSIZE]; +}; + +#define BUFFER_ITEM_PER_CPU 100 + +struct percpu_buffer_node { + intptr_t data; +}; + +struct percpu_buffer_entry { + intptr_t offset; + intptr_t buflen; + struct percpu_buffer_node **array; +} __attribute__((aligned(128))); + +struct percpu_buffer { + struct percpu_buffer_entry c[CPU_SETSIZE]; +}; + +#define MEMCPY_BUFFER_ITEM_PER_CPU 100 + +struct percpu_memcpy_buffer_node { + intptr_t data1; + uint64_t data2; +}; + +struct percpu_memcpy_buffer_entry { + intptr_t offset; + intptr_t buflen; + struct percpu_memcpy_buffer_node *array; +} __attribute__((aligned(128))); + +struct percpu_memcpy_buffer { + struct percpu_memcpy_buffer_entry c[CPU_SETSIZE]; +}; + +/* A simple percpu spinlock. */ +static void rseq_percpu_lock(struct percpu_lock *lock, int cpu) +{ + for (;;) { + int ret; + + ret = percpu_cmpeqv_storev(&lock->c[cpu].v, + 0, 1, cpu); + if (rseq_likely(!ret)) + break; + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + /* Retry if comparison fails. */ + } + /* + * Acquire semantic when taking lock after control dependency. + * Matches rseq_smp_store_release(). + */ + rseq_smp_acquire__after_ctrl_dep(); +} + +static void rseq_percpu_unlock(struct percpu_lock *lock, int cpu) +{ + assert(lock->c[cpu].v == 1); + /* + * Release lock, with release semantic. Matches + * rseq_smp_acquire__after_ctrl_dep(). + */ + rseq_smp_store_release(&lock->c[cpu].v, 0); +} + +void *test_percpu_spinlock_thread(void *arg) +{ + struct spinlock_thread_test_data *thread_data = arg; + struct spinlock_test_data *data = thread_data->data; + long long i, reps; + + if (!opt_disable_rseq && thread_data->reg && + rseq_register_current_thread()) + abort(); + reps = thread_data->reps; + for (i = 0; i < reps; i++) { + int cpu = rseq_cpu_start(); + + rseq_percpu_lock(&data->lock, cpu); + data->c[cpu].count++; + rseq_percpu_unlock(&data->lock, cpu); +#ifndef BENCHMARK + if (i != 0 && !(i % (reps / 10))) + printf_verbose("tid %d: count %lld\n", (int) gettid(), i); +#endif + } + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && thread_data->reg && + rseq_unregister_current_thread()) + abort(); + return NULL; +} + +/* + * A simple test which implements a sharded counter using a per-cpu + * lock. Obviously real applications might prefer to simply use a + * per-cpu increment; however, this is reasonable for a test and the + * lock can be extended to synchronize more complicated operations. + */ +void test_percpu_spinlock(void) +{ + const int num_threads = opt_threads; + int i, ret; + uint64_t sum; + pthread_t test_threads[num_threads]; + struct spinlock_test_data data; + struct spinlock_thread_test_data thread_data[num_threads]; + + memset(&data, 0, sizeof(data)); + for (i = 0; i < num_threads; i++) { + thread_data[i].reps = opt_reps; + if (opt_disable_mod <= 0 || (i % opt_disable_mod)) + thread_data[i].reg = 1; + else + thread_data[i].reg = 0; + thread_data[i].data = &data; + ret = pthread_create(&test_threads[i], NULL, + test_percpu_spinlock_thread, + &thread_data[i]); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + sum = 0; + for (i = 0; i < CPU_SETSIZE; i++) + sum += data.c[i].count; + + assert(sum == (uint64_t)opt_reps * num_threads); +} + +void *test_percpu_inc_thread(void *arg) +{ + struct inc_thread_test_data *thread_data = arg; + struct inc_test_data *data = thread_data->data; + long long i, reps; + + if (!opt_disable_rseq && thread_data->reg && + rseq_register_current_thread()) + abort(); + reps = thread_data->reps; + for (i = 0; i < reps; i++) { + int cpu, ret; + + cpu = rseq_cpu_start(); + ret = percpu_addv(&data->c[cpu].count, 1, cpu); + if (rseq_unlikely(ret)) { + perror("cpu_opv"); + abort(); + } +#ifndef BENCHMARK + if (i != 0 && !(i % (reps / 10))) + printf_verbose("tid %d: count %lld\n", (int) gettid(), i); +#endif + } + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && thread_data->reg && + rseq_unregister_current_thread()) + abort(); + return NULL; +} + +void test_percpu_inc(void) +{ + const int num_threads = opt_threads; + int i, ret; + uint64_t sum; + pthread_t test_threads[num_threads]; + struct inc_test_data data; + struct inc_thread_test_data thread_data[num_threads]; + + memset(&data, 0, sizeof(data)); + for (i = 0; i < num_threads; i++) { + thread_data[i].reps = opt_reps; + if (opt_disable_mod <= 0 || (i % opt_disable_mod)) + thread_data[i].reg = 1; + else + thread_data[i].reg = 0; + thread_data[i].data = &data; + ret = pthread_create(&test_threads[i], NULL, + test_percpu_inc_thread, + &thread_data[i]); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + sum = 0; + for (i = 0; i < CPU_SETSIZE; i++) + sum += data.c[i].count; + + assert(sum == (uint64_t)opt_reps * num_threads); +} + +void percpu_list_push(struct percpu_list *list, + struct percpu_list_node *node, + int cpu) +{ + for (;;) { + intptr_t *targetptr, newval, expect; + int ret; + + /* Load list->c[cpu].head with single-copy atomicity. */ + expect = (intptr_t)RSEQ_READ_ONCE(list->c[cpu].head); + newval = (intptr_t)node; + targetptr = (intptr_t *)&list->c[cpu].head; + node->next = (struct percpu_list_node *)expect; + ret = percpu_cmpeqv_storev(targetptr, expect, newval, cpu); + if (rseq_likely(!ret)) + break; + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + /* Retry if comparison fails. */ + } +} + +/* + * Unlike a traditional lock-less linked list; the availability of a + * rseq primitive allows us to implement pop without concerns over + * ABA-type races. + */ +struct percpu_list_node *percpu_list_pop(struct percpu_list *list, + int cpu) +{ + struct percpu_list_node *head; + intptr_t *targetptr, expectnot, *load; + off_t offset; + int ret; + + targetptr = (intptr_t *)&list->c[cpu].head; + expectnot = (intptr_t)NULL; + offset = offsetof(struct percpu_list_node, next); + load = (intptr_t *)&head; + ret = percpu_cmpnev_storeoffp_load(targetptr, expectnot, + offset, load, cpu); + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + if (ret > 0) + return NULL; + return head; +} + +void *test_percpu_list_thread(void *arg) +{ + long long i, reps; + struct percpu_list *list = (struct percpu_list *)arg; + + if (!opt_disable_rseq && rseq_register_current_thread()) + abort(); + + reps = opt_reps; + for (i = 0; i < reps; i++) { + struct percpu_list_node *node; + + node = percpu_list_pop(list, rseq_cpu_start()); + if (opt_yield) + sched_yield(); /* encourage shuffling */ + if (node) + percpu_list_push(list, node, rseq_cpu_start()); + } + + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && rseq_unregister_current_thread()) + abort(); + + return NULL; +} + +/* Simultaneous modification to a per-cpu linked list from many threads. */ +void test_percpu_list(void) +{ + const int num_threads = opt_threads; + int i, j, ret; + uint64_t sum = 0, expected_sum = 0; + struct percpu_list list; + pthread_t test_threads[num_threads]; + cpu_set_t allowed_cpus; + + memset(&list, 0, sizeof(list)); + + /* Generate list entries for every usable cpu. */ + sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus); + for (i = 0; i < CPU_SETSIZE; i++) { + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + for (j = 1; j <= 100; j++) { + struct percpu_list_node *node; + + expected_sum += j; + + node = malloc(sizeof(*node)); + assert(node); + node->data = j; + node->next = list.c[i].head; + list.c[i].head = node; + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_create(&test_threads[i], NULL, + test_percpu_list_thread, &list); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + for (i = 0; i < CPU_SETSIZE; i++) { + struct percpu_list_node *node; + + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + + while ((node = percpu_list_pop(&list, i))) { + sum += node->data; + free(node); + } + } + + /* + * All entries should now be accounted for (unless some external + * actor is interfering with our allowed affinity while this + * test is running). + */ + assert(sum == expected_sum); +} + +bool percpu_buffer_push(struct percpu_buffer *buffer, + struct percpu_buffer_node *node, + int cpu) +{ + for (;;) { + intptr_t *targetptr_spec, newval_spec; + intptr_t *targetptr_final, newval_final; + intptr_t offset; + int ret; + + offset = RSEQ_READ_ONCE(buffer->c[cpu].offset); + if (offset == buffer->c[cpu].buflen) + return false; + newval_spec = (intptr_t)node; + targetptr_spec = (intptr_t *)&buffer->c[cpu].array[offset]; + newval_final = offset + 1; + targetptr_final = &buffer->c[cpu].offset; + if (opt_mb) + ret = percpu_cmpeqv_storev_storev_release( + targetptr_final, offset, targetptr_spec, + newval_spec, newval_final, cpu); + else + ret = percpu_cmpeqv_storev_storev(targetptr_final, + offset, targetptr_spec, newval_spec, + newval_final, cpu); + if (rseq_likely(!ret)) + break; + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + /* Retry if comparison fails. */ + } + return true; +} + +struct percpu_buffer_node *percpu_buffer_pop(struct percpu_buffer *buffer, + int cpu) +{ + struct percpu_buffer_node *head; + + for (;;) { + intptr_t *targetptr, newval; + intptr_t offset; + int ret; + + /* Load offset with single-copy atomicity. */ + offset = RSEQ_READ_ONCE(buffer->c[cpu].offset); + if (offset == 0) + return NULL; + head = RSEQ_READ_ONCE(buffer->c[cpu].array[offset - 1]); + newval = offset - 1; + targetptr = (intptr_t *)&buffer->c[cpu].offset; + ret = percpu_cmpeqv_cmpeqv_storev(targetptr, offset, + (intptr_t *)&buffer->c[cpu].array[offset - 1], + (intptr_t)head, newval, cpu); + if (rseq_likely(!ret)) + break; + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + /* Retry if comparison fails. */ + } + return head; +} + +void *test_percpu_buffer_thread(void *arg) +{ + long long i, reps; + struct percpu_buffer *buffer = (struct percpu_buffer *)arg; + + if (!opt_disable_rseq && rseq_register_current_thread()) + abort(); + + reps = opt_reps; + for (i = 0; i < reps; i++) { + struct percpu_buffer_node *node; + + node = percpu_buffer_pop(buffer, rseq_cpu_start()); + if (opt_yield) + sched_yield(); /* encourage shuffling */ + if (node) { + if (!percpu_buffer_push(buffer, node, + rseq_cpu_start())) { + /* Should increase buffer size. */ + abort(); + } + } + } + + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && rseq_unregister_current_thread()) + abort(); + + return NULL; +} + +/* Simultaneous modification to a per-cpu buffer from many threads. */ +void test_percpu_buffer(void) +{ + const int num_threads = opt_threads; + int i, j, ret; + uint64_t sum = 0, expected_sum = 0; + struct percpu_buffer buffer; + pthread_t test_threads[num_threads]; + cpu_set_t allowed_cpus; + + memset(&buffer, 0, sizeof(buffer)); + + /* Generate list entries for every usable cpu. */ + sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus); + for (i = 0; i < CPU_SETSIZE; i++) { + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + /* Worse-case is every item in same CPU. */ + buffer.c[i].array = + malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE * + BUFFER_ITEM_PER_CPU); + assert(buffer.c[i].array); + buffer.c[i].buflen = CPU_SETSIZE * BUFFER_ITEM_PER_CPU; + for (j = 1; j <= BUFFER_ITEM_PER_CPU; j++) { + struct percpu_buffer_node *node; + + expected_sum += j; + + /* + * We could theoretically put the word-sized + * "data" directly in the buffer. However, we + * want to model objects that would not fit + * within a single word, so allocate an object + * for each node. + */ + node = malloc(sizeof(*node)); + assert(node); + node->data = j; + buffer.c[i].array[j - 1] = node; + buffer.c[i].offset++; + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_create(&test_threads[i], NULL, + test_percpu_buffer_thread, &buffer); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + for (i = 0; i < CPU_SETSIZE; i++) { + struct percpu_buffer_node *node; + + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + + while ((node = percpu_buffer_pop(&buffer, i))) { + sum += node->data; + free(node); + } + free(buffer.c[i].array); + } + + /* + * All entries should now be accounted for (unless some external + * actor is interfering with our allowed affinity while this + * test is running). + */ + assert(sum == expected_sum); +} + +bool percpu_memcpy_buffer_push(struct percpu_memcpy_buffer *buffer, + struct percpu_memcpy_buffer_node item, int cpu) +{ + for (;;) { + intptr_t *targetptr_final, newval_final, offset; + char *destptr, *srcptr; + size_t copylen; + int ret; + + /* Load offset with single-copy atomicity. */ + offset = RSEQ_READ_ONCE(buffer->c[cpu].offset); + if (offset == buffer->c[cpu].buflen) + return false; + destptr = (char *)&buffer->c[cpu].array[offset]; + srcptr = (char *)&item; + /* copylen must be <= 4kB. */ + copylen = sizeof(item); + newval_final = offset + 1; + targetptr_final = &buffer->c[cpu].offset; + if (opt_mb) + ret = percpu_cmpeqv_memcpy_storev_release( + targetptr_final, offset, + destptr, srcptr, copylen, + newval_final, cpu); + else + ret = percpu_cmpeqv_memcpy_storev(targetptr_final, + offset, destptr, srcptr, copylen, + newval_final, cpu); + if (rseq_likely(!ret)) + break; + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + /* Retry if comparison fails. */ + } + return true; +} + +bool percpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer, + struct percpu_memcpy_buffer_node *item, int cpu) +{ + for (;;) { + intptr_t *targetptr_final, newval_final, offset; + char *destptr, *srcptr; + size_t copylen; + int ret; + + /* Load offset with single-copy atomicity. */ + offset = RSEQ_READ_ONCE(buffer->c[cpu].offset); + if (offset == 0) + return false; + destptr = (char *)item; + srcptr = (char *)&buffer->c[cpu].array[offset - 1]; + /* copylen must be <= 4kB. */ + copylen = sizeof(*item); + newval_final = offset - 1; + targetptr_final = &buffer->c[cpu].offset; + ret = percpu_cmpeqv_memcpy_storev(targetptr_final, + offset, destptr, srcptr, copylen, + newval_final, cpu); + if (rseq_likely(!ret)) + break; + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + /* Retry if comparison fails. */ + } + return true; +} + +void *test_percpu_memcpy_buffer_thread(void *arg) +{ + long long i, reps; + struct percpu_memcpy_buffer *buffer = (struct percpu_memcpy_buffer *)arg; + + if (!opt_disable_rseq && rseq_register_current_thread()) + abort(); + + reps = opt_reps; + for (i = 0; i < reps; i++) { + struct percpu_memcpy_buffer_node item; + bool result; + + result = percpu_memcpy_buffer_pop(buffer, &item, + rseq_cpu_start()); + if (opt_yield) + sched_yield(); /* encourage shuffling */ + if (result) { + if (!percpu_memcpy_buffer_push(buffer, item, + rseq_cpu_start())) { + /* Should increase buffer size. */ + abort(); + } + } + } + + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && rseq_unregister_current_thread()) + abort(); + + return NULL; +} + +/* Simultaneous modification to a per-cpu buffer from many threads. */ +void test_percpu_memcpy_buffer(void) +{ + const int num_threads = opt_threads; + int i, j, ret; + uint64_t sum = 0, expected_sum = 0; + struct percpu_memcpy_buffer buffer; + pthread_t test_threads[num_threads]; + cpu_set_t allowed_cpus; + + memset(&buffer, 0, sizeof(buffer)); + + /* Generate list entries for every usable cpu. */ + sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus); + for (i = 0; i < CPU_SETSIZE; i++) { + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + /* Worse-case is every item in same CPU. */ + buffer.c[i].array = + malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE * + MEMCPY_BUFFER_ITEM_PER_CPU); + assert(buffer.c[i].array); + buffer.c[i].buflen = CPU_SETSIZE * MEMCPY_BUFFER_ITEM_PER_CPU; + for (j = 1; j <= MEMCPY_BUFFER_ITEM_PER_CPU; j++) { + expected_sum += 2 * j + 1; + + /* + * We could theoretically put the word-sized + * "data" directly in the buffer. However, we + * want to model objects that would not fit + * within a single word, so allocate an object + * for each node. + */ + buffer.c[i].array[j - 1].data1 = j; + buffer.c[i].array[j - 1].data2 = j + 1; + buffer.c[i].offset++; + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_create(&test_threads[i], NULL, + test_percpu_memcpy_buffer_thread, + &buffer); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + for (i = 0; i < CPU_SETSIZE; i++) { + struct percpu_memcpy_buffer_node item; + + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + + while (percpu_memcpy_buffer_pop(&buffer, &item, i)) { + sum += item.data1; + sum += item.data2; + } + free(buffer.c[i].array); + } + + /* + * All entries should now be accounted for (unless some external + * actor is interfering with our allowed affinity while this + * test is running). + */ + assert(sum == expected_sum); +} + +static void test_signal_interrupt_handler(int signo) +{ + signals_delivered++; +} + +static int set_signal_handler(void) +{ + int ret = 0; + struct sigaction sa; + sigset_t sigset; + + ret = sigemptyset(&sigset); + if (ret < 0) { + perror("sigemptyset"); + return ret; + } + + sa.sa_handler = test_signal_interrupt_handler; + sa.sa_mask = sigset; + sa.sa_flags = 0; + ret = sigaction(SIGUSR1, &sa, NULL); + if (ret < 0) { + perror("sigaction"); + return ret; + } + + printf_verbose("Signal handler set for SIGUSR1\n"); + + return ret; +} + +static void show_usage(int argc, char **argv) +{ + printf("Usage : %s <OPTIONS>\n", + argv[0]); + printf("OPTIONS:\n"); + printf(" [-1 loops] Number of loops for delay injection 1\n"); + printf(" [-2 loops] Number of loops for delay injection 2\n"); + printf(" [-3 loops] Number of loops for delay injection 3\n"); + printf(" [-4 loops] Number of loops for delay injection 4\n"); + printf(" [-5 loops] Number of loops for delay injection 5\n"); + printf(" [-6 loops] Number of loops for delay injection 6\n"); + printf(" [-7 loops] Number of loops for delay injection 7 (-1 to enable -m)\n"); + printf(" [-8 loops] Number of loops for delay injection 8 (-1 to enable -m)\n"); + printf(" [-9 loops] Number of loops for delay injection 9 (-1 to enable -m)\n"); + printf(" [-m N] Yield/sleep/kill every modulo N (default 0: disabled) (>= 0)\n"); + printf(" [-y] Yield\n"); + printf(" [-k] Kill thread with signal\n"); + printf(" [-s S] S: =0: disabled (default), >0: sleep time (ms)\n"); + printf(" [-t N] Number of threads (default 200)\n"); + printf(" [-r N] Number of repetitions per thread (default 5000)\n"); + printf(" [-d] Disable rseq system call (no initialization)\n"); + printf(" [-D M] Disable rseq for each M threads\n"); + printf(" [-T test] Choose test: (s)pinlock, (l)ist, (b)uffer, (m)emcpy, (i)ncrement\n"); + printf(" [-M] Push into buffer and memcpy buffer with memory barriers.\n"); + printf(" [-v] Verbose output.\n"); + printf(" [-h] Show this help.\n"); + printf("\n"); +} + +int main(int argc, char **argv) +{ + int i; + + for (i = 1; i < argc; i++) { + if (argv[i][0] != '-') + continue; + switch (argv[i][1]) { + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + loop_cnt[argv[i][1] - '0'] = atol(argv[i + 1]); + i++; + break; + case 'm': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_modulo = atol(argv[i + 1]); + if (opt_modulo < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 's': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_sleep = atol(argv[i + 1]); + if (opt_sleep < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 'y': + opt_yield = 1; + break; + case 'k': + opt_signal = 1; + break; + case 'd': + opt_disable_rseq = 1; + break; + case 'D': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_disable_mod = atol(argv[i + 1]); + if (opt_disable_mod < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 't': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_threads = atol(argv[i + 1]); + if (opt_threads < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 'r': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_reps = atoll(argv[i + 1]); + if (opt_reps < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 'h': + show_usage(argc, argv); + goto end; + case 'T': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_test = *argv[i + 1]; + switch (opt_test) { + case 's': + case 'l': + case 'i': + case 'b': + case 'm': + break; + default: + show_usage(argc, argv); + goto error; + } + i++; + break; + case 'v': + verbose = 1; + break; + case 'M': + opt_mb = 1; + break; + default: + show_usage(argc, argv); + goto error; + } + } + + loop_cnt_1 = loop_cnt[1]; + loop_cnt_2 = loop_cnt[2]; + loop_cnt_3 = loop_cnt[3]; + loop_cnt_4 = loop_cnt[4]; + loop_cnt_5 = loop_cnt[5]; + loop_cnt_6 = loop_cnt[6]; + + if (set_signal_handler()) + goto error; + + if (!opt_disable_rseq && rseq_register_current_thread()) + goto error; + switch (opt_test) { + case 's': + printf_verbose("spinlock\n"); + test_percpu_spinlock(); + break; + case 'l': + printf_verbose("linked list\n"); + test_percpu_list(); + break; + case 'b': + printf_verbose("buffer\n"); + test_percpu_buffer(); + break; + case 'm': + printf_verbose("memcpy buffer\n"); + test_percpu_memcpy_buffer(); + break; + case 'i': + printf_verbose("counter increment\n"); + test_percpu_inc(); + break; + } + if (!opt_disable_rseq && rseq_unregister_current_thread()) + abort(); +end: + return 0; + +error: + return -1; +} -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

6 years, 9 months

1
0
0 0

[RFC PATCH for 4.17 19/21] rseq: selftests: Provide basic percpu ops test

by Mathieu Desnoyers

"basic_percpu_ops_test" is a slightly more "realistic" variant, implementing a few simple per-cpu operations and testing their correctness. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> CC: Shuah Khan <shuahkh(a)osg.samsung.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Paul Turner <pjt(a)google.com> CC: Andrew Hunter <ahh(a)google.com> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andi Kleen <andi(a)firstfloor.org> CC: Dave Watson <davejwatson(a)fb.com> CC: Chris Lameter <cl(a)linux.com> CC: Ingo Molnar <mingo(a)redhat.com> CC: "H. Peter Anvin" <hpa(a)zytor.com> CC: Ben Maurer <bmaurer(a)fb.com> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: "Paul E. McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: linux-kselftest(a)vger.kernel.org CC: linux-api(a)vger.kernel.org --- .../testing/selftests/rseq/basic_percpu_ops_test.c | 296 +++++++++++++++++++++ 1 file changed, 296 insertions(+) create mode 100644 tools/testing/selftests/rseq/basic_percpu_ops_test.c diff --git a/tools/testing/selftests/rseq/basic_percpu_ops_test.c b/tools/testing/selftests/rseq/basic_percpu_ops_test.c new file mode 100644 index 000000000000..e585bba0bf8d --- /dev/null +++ b/tools/testing/selftests/rseq/basic_percpu_ops_test.c @@ -0,0 +1,296 @@ +#define _GNU_SOURCE +#include <assert.h> +#include <pthread.h> +#include <sched.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <stddef.h> + +#include "percpu-op.h" + +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) + +struct percpu_lock_entry { + intptr_t v; +} __attribute__((aligned(128))); + +struct percpu_lock { + struct percpu_lock_entry c[CPU_SETSIZE]; +}; + +struct test_data_entry { + intptr_t count; +} __attribute__((aligned(128))); + +struct spinlock_test_data { + struct percpu_lock lock; + struct test_data_entry c[CPU_SETSIZE]; + int reps; +}; + +struct percpu_list_node { + intptr_t data; + struct percpu_list_node *next; +}; + +struct percpu_list_entry { + struct percpu_list_node *head; +} __attribute__((aligned(128))); + +struct percpu_list { + struct percpu_list_entry c[CPU_SETSIZE]; +}; + +/* A simple percpu spinlock. Returns the cpu lock was acquired on. */ +int rseq_percpu_lock(struct percpu_lock *lock) +{ + int cpu; + + for (;;) { + int ret; + + cpu = rseq_cpu_start(); + ret = percpu_cmpeqv_storev(&lock->c[cpu].v, + 0, 1, cpu); + if (rseq_likely(!ret)) + break; + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + /* Retry if comparison fails. */ + } + /* + * Acquire semantic when taking lock after control dependency. + * Matches rseq_smp_store_release(). + */ + rseq_smp_acquire__after_ctrl_dep(); + return cpu; +} + +void rseq_percpu_unlock(struct percpu_lock *lock, int cpu) +{ + assert(lock->c[cpu].v == 1); + /* + * Release lock, with release semantic. Matches + * rseq_smp_acquire__after_ctrl_dep(). + */ + rseq_smp_store_release(&lock->c[cpu].v, 0); +} + +void *test_percpu_spinlock_thread(void *arg) +{ + struct spinlock_test_data *data = arg; + int i, cpu; + + if (rseq_register_current_thread()) { + fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + abort(); + } + for (i = 0; i < data->reps; i++) { + cpu = rseq_percpu_lock(&data->lock); + data->c[cpu].count++; + rseq_percpu_unlock(&data->lock, cpu); + } + if (rseq_unregister_current_thread()) { + fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + abort(); + } + + return NULL; +} + +/* + * A simple test which implements a sharded counter using a per-cpu + * lock. Obviously real applications might prefer to simply use a + * per-cpu increment; however, this is reasonable for a test and the + * lock can be extended to synchronize more complicated operations. + */ +void test_percpu_spinlock(void) +{ + const int num_threads = 200; + int i; + uint64_t sum; + pthread_t test_threads[num_threads]; + struct spinlock_test_data data; + + memset(&data, 0, sizeof(data)); + data.reps = 5000; + + for (i = 0; i < num_threads; i++) + pthread_create(&test_threads[i], NULL, + test_percpu_spinlock_thread, &data); + + for (i = 0; i < num_threads; i++) + pthread_join(test_threads[i], NULL); + + sum = 0; + for (i = 0; i < CPU_SETSIZE; i++) + sum += data.c[i].count; + + assert(sum == (uint64_t)data.reps * num_threads); +} + +int percpu_list_push(struct percpu_list *list, struct percpu_list_node *node, + int cpu) +{ + for (;;) { + intptr_t *targetptr, newval, expect; + int ret; + + /* Load list->c[cpu].head with single-copy atomicity. */ + expect = (intptr_t)RSEQ_READ_ONCE(list->c[cpu].head); + newval = (intptr_t)node; + targetptr = (intptr_t *)&list->c[cpu].head; + node->next = (struct percpu_list_node *)expect; + ret = percpu_cmpeqv_storev(targetptr, expect, newval, cpu); + if (rseq_likely(!ret)) + break; + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + /* Retry if comparison fails. */ + } + return cpu; +} + +/* + * Unlike a traditional lock-less linked list; the availability of a + * rseq primitive allows us to implement pop without concerns over + * ABA-type races. + */ +struct percpu_list_node *percpu_list_pop(struct percpu_list *list, + int cpu) +{ + struct percpu_list_node *head; + intptr_t *targetptr, expectnot, *load; + off_t offset; + int ret; + + targetptr = (intptr_t *)&list->c[cpu].head; + expectnot = (intptr_t)NULL; + offset = offsetof(struct percpu_list_node, next); + load = (intptr_t *)&head; + ret = percpu_cmpnev_storeoffp_load(targetptr, expectnot, + offset, load, cpu); + if (rseq_unlikely(ret < 0)) { + perror("cpu_opv"); + abort(); + } + if (ret > 0) + return NULL; + return head; +} + +void *test_percpu_list_thread(void *arg) +{ + int i; + struct percpu_list *list = (struct percpu_list *)arg; + + if (rseq_register_current_thread()) { + fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + abort(); + } + + for (i = 0; i < 100000; i++) { + struct percpu_list_node *node; + + node = percpu_list_pop(list, rseq_cpu_start()); + sched_yield(); /* encourage shuffling */ + if (node) + percpu_list_push(list, node, rseq_cpu_start()); + } + + if (rseq_unregister_current_thread()) { + fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + abort(); + } + + return NULL; +} + +/* Simultaneous modification to a per-cpu linked list from many threads. */ +void test_percpu_list(void) +{ + int i, j; + uint64_t sum = 0, expected_sum = 0; + struct percpu_list list; + pthread_t test_threads[200]; + cpu_set_t allowed_cpus; + + memset(&list, 0, sizeof(list)); + + /* Generate list entries for every usable cpu. */ + sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus); + for (i = 0; i < CPU_SETSIZE; i++) { + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + for (j = 1; j <= 100; j++) { + struct percpu_list_node *node; + + expected_sum += j; + + node = malloc(sizeof(*node)); + assert(node); + node->data = j; + node->next = list.c[i].head; + list.c[i].head = node; + } + } + + for (i = 0; i < 200; i++) + pthread_create(&test_threads[i], NULL, + test_percpu_list_thread, &list); + + for (i = 0; i < 200; i++) + pthread_join(test_threads[i], NULL); + + for (i = 0; i < CPU_SETSIZE; i++) { + struct percpu_list_node *node; + + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + + while ((node = percpu_list_pop(&list, i))) { + sum += node->data; + free(node); + } + } + + /* + * All entries should now be accounted for (unless some external + * actor is interfering with our allowed affinity while this + * test is running). + */ + assert(sum == expected_sum); +} + +int main(int argc, char **argv) +{ + if (rseq_register_current_thread()) { + fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + goto error; + } + printf("spinlock\n"); + test_percpu_spinlock(); + printf("percpu_list\n"); + test_percpu_list(); + if (rseq_unregister_current_thread()) { + fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + goto error; + } + return 0; + +error: + return -1; +} + -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

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