diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-16 09:26:42 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-16 09:26:42 -0800 |
commit | de399813b521ea7e38bbfb5e5b620b5e202e5783 (patch) | |
tree | ceb8302f9d6a7a4f2e25b64c5dc42c1fb80b435b /tools/testing/selftests/powerpc/benchmarks/null_syscall.c | |
parent | 57ca04ab440168e101da746ef9edd1ec583b7214 (diff) | |
parent | c6f6634721c871bfab4235e1cbcad208d3063798 (diff) |
Merge tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Highlights include:
- Support for the kexec_file_load() syscall, which is a prereq for
secure and trusted boot.
- Prevent kernel execution of userspace on P9 Radix (similar to
SMEP/PXN).
- Sort the exception tables at build time, to save time at boot, and
store them as relative offsets to save space in the kernel image &
memory.
- Allow building the kernel with thin archives, which should allow us
to build an allyesconfig once some other fixes land.
- Build fixes to allow us to correctly rebuild when changing the
kernel endian from big to little or vice versa.
- Plumbing so that we can avoid doing a full mm TLB flush on P9
Radix.
- Initial stack protector support (-fstack-protector).
- Support for dumping the radix (aka. Linux) and hash page tables via
debugfs.
- Fix an oops in cxl coredump generation when cxl_get_fd() is used.
- Freescale updates from Scott: "Highlights include 8xx hugepage
support, qbman fixes/cleanup, device tree updates, and some misc
cleanup."
- Many and varied fixes and minor enhancements as always.
Thanks to:
Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anshuman
Khandual, Anton Blanchard, Balbir Singh, Bartlomiej Zolnierkiewicz,
Christophe Jaillet, Christophe Leroy, Denis Kirjanov, Elimar
Riesebieter, Frederic Barrat, Gautham R. Shenoy, Geliang Tang, Geoff
Levand, Jack Miller, Johan Hovold, Lars-Peter Clausen, Libin,
Madhavan Srinivasan, Michael Neuling, Nathan Fontenot, Naveen N.
Rao, Nicholas Piggin, Pan Xinhui, Peter Senna Tschudin, Rashmica
Gupta, Rui Teng, Russell Currey, Scott Wood, Simon Guo, Suraj
Jitindar Singh, Thiago Jung Bauermann, Tobias Klauser, Vaibhav Jain"
[ And thanks to Michael, who took time off from a new baby to get this
pull request done. - Linus ]
* tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (174 commits)
powerpc/fsl/dts: add FMan node for t1042d4rdb
powerpc/fsl/dts: add sg_2500_aqr105_phy4 alias on t1024rdb
powerpc/fsl/dts: add QMan and BMan nodes on t1024
powerpc/fsl/dts: add QMan and BMan nodes on t1023
soc/fsl/qman: test: use DEFINE_SPINLOCK()
powerpc/fsl-lbc: use DEFINE_SPINLOCK()
powerpc/8xx: Implement support of hugepages
powerpc: get hugetlbpage handling more generic
powerpc: port 64 bits pgtable_cache to 32 bits
powerpc/boot: Request no dynamic linker for boot wrapper
soc/fsl/bman: Use resource_size instead of computation
soc/fsl/qe: use builtin_platform_driver
powerpc/fsl_pmc: use builtin_platform_driver
powerpc/83xx/suspend: use builtin_platform_driver
powerpc/ftrace: Fix the comments for ftrace_modify_code
powerpc/perf: macros for power9 format encoding
powerpc/perf: power9 raw event format encoding
powerpc/perf: update attribute_group data structure
powerpc/perf: factor out the event format field
powerpc/mm/iommu, vfio/spapr: Put pages on VFIO container shutdown
...
Diffstat (limited to 'tools/testing/selftests/powerpc/benchmarks/null_syscall.c')
-rw-r--r-- | tools/testing/selftests/powerpc/benchmarks/null_syscall.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/benchmarks/null_syscall.c b/tools/testing/selftests/powerpc/benchmarks/null_syscall.c new file mode 100644 index 000000000000..ecc14d68e101 --- /dev/null +++ b/tools/testing/selftests/powerpc/benchmarks/null_syscall.c @@ -0,0 +1,157 @@ +/* + * Test null syscall performance + * + * Copyright (C) 2009-2015 Anton Blanchard, IBM + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#define NR_LOOPS 10000000 + +#include <string.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <time.h> +#include <sys/types.h> +#include <sys/time.h> +#include <signal.h> + +static volatile int soak_done; +unsigned long long clock_frequency; +unsigned long long timebase_frequency; +double timebase_multiplier; + +static inline unsigned long long mftb(void) +{ + unsigned long low; + + asm volatile("mftb %0" : "=r" (low)); + + return low; +} + +static void sigalrm_handler(int unused) +{ + soak_done = 1; +} + +/* + * Use a timer instead of busy looping on clock_gettime() so we don't + * pollute profiles with glibc and VDSO hits. + */ +static void cpu_soak_usecs(unsigned long usecs) +{ + struct itimerval val; + + memset(&val, 0, sizeof(val)); + val.it_value.tv_usec = usecs; + + signal(SIGALRM, sigalrm_handler); + setitimer(ITIMER_REAL, &val, NULL); + + while (1) { + if (soak_done) + break; + } + + signal(SIGALRM, SIG_DFL); +} + +/* + * This only works with recent kernels where cpufreq modifies + * /proc/cpuinfo dynamically. + */ +static void get_proc_frequency(void) +{ + FILE *f; + char line[128]; + char *p, *end; + unsigned long v; + double d; + char *override; + + /* Try to get out of low power/low frequency mode */ + cpu_soak_usecs(0.25 * 1000000); + + f = fopen("/proc/cpuinfo", "r"); + if (f == NULL) + return; + + timebase_frequency = 0; + + while (fgets(line, sizeof(line), f) != NULL) { + if (strncmp(line, "timebase", 8) == 0) { + p = strchr(line, ':'); + if (p != NULL) { + v = strtoull(p + 1, &end, 0); + if (end != p + 1) + timebase_frequency = v; + } + } + + if (((strncmp(line, "clock", 5) == 0) || + (strncmp(line, "cpu MHz", 7) == 0))) { + p = strchr(line, ':'); + if (p != NULL) { + d = strtod(p + 1, &end); + if (end != p + 1) { + /* Find fastest clock frequency */ + if ((d * 1000000ULL) > clock_frequency) + clock_frequency = d * 1000000ULL; + } + } + } + } + + fclose(f); + + override = getenv("FREQUENCY"); + if (override) + clock_frequency = strtoull(override, NULL, 10); + + if (timebase_frequency) + timebase_multiplier = (double)clock_frequency + / timebase_frequency; + else + timebase_multiplier = 1; +} + +static void do_null_syscall(unsigned long nr) +{ + unsigned long i; + + for (i = 0; i < nr; i++) + getppid(); +} + +#define TIME(A, STR) \ + +int main(void) +{ + unsigned long tb_start, tb_now; + struct timespec tv_start, tv_now; + unsigned long long elapsed_ns, elapsed_tb; + + get_proc_frequency(); + + clock_gettime(CLOCK_MONOTONIC, &tv_start); + tb_start = mftb(); + + do_null_syscall(NR_LOOPS); + + clock_gettime(CLOCK_MONOTONIC, &tv_now); + tb_now = mftb(); + + elapsed_ns = (tv_now.tv_sec - tv_start.tv_sec) * 1000000000ULL + + (tv_now.tv_nsec - tv_start.tv_nsec); + elapsed_tb = tb_now - tb_start; + + printf("%10.2f ns %10.2f cycles\n", (float)elapsed_ns / NR_LOOPS, + (float)elapsed_tb * timebase_multiplier / NR_LOOPS); + + return 0; +} |