Message ID | 20210315104223.32542-1-lukma@denx.de |
---|---|
State | New |
Headers | show |
Series | tst: Provide test for getrusage | expand |
On Mär 15 2021, Lukasz Majewski wrote: > diff --git a/sysdeps/unix/sysv/linux/tst-getrusage.c b/sysdeps/unix/sysv/linux/tst-getrusage.c > new file mode 100644 > index 0000000000..068becdadb > --- /dev/null > +++ b/sysdeps/unix/sysv/linux/tst-getrusage.c > @@ -0,0 +1,55 @@ > +/* Test for getrusage > + Copyright (C) 2021 Free Software Foundation, Inc. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library is distributed in the hope that it will be useful, > + but WITHOUT ANY WARRANTY; without even the implied warranty of > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + <https://www.gnu.org/licenses/>. */ > + > +#include <time.h> > +#include <sys/resource.h> > +#include <support/check.h> > +#include <support/timespec.h> > + > +#define TST_GETRUSAGE_TIMEOUT 1 > + > +static int > +do_test (void) > +{ > + struct timespec tv_then, tv_now, gru_u, gru_s, s, r; > + struct rusage ru; > + int ret; > + > + tv_then = xclock_now (CLOCK_REALTIME); > + /* Busy wait for 1 second. */ > + do > + { > + tv_now = xclock_now (CLOCK_REALTIME); > + r = timespec_sub (tv_now, tv_then); > + } while ( r.tv_sec != TST_GETRUSAGE_TIMEOUT ); What happens if the process stalls for a second? Andreas.
Hi Andreas, > On Mär 15 2021, Lukasz Majewski wrote: > > > diff --git a/sysdeps/unix/sysv/linux/tst-getrusage.c > > b/sysdeps/unix/sysv/linux/tst-getrusage.c new file mode 100644 > > index 0000000000..068becdadb > > --- /dev/null > > +++ b/sysdeps/unix/sysv/linux/tst-getrusage.c > > @@ -0,0 +1,55 @@ > > +/* Test for getrusage > > + Copyright (C) 2021 Free Software Foundation, Inc. > > + This file is part of the GNU C Library. > > + > > + The GNU C Library is free software; you can redistribute it > > and/or > > + modify it under the terms of the GNU Lesser General Public > > + License as published by the Free Software Foundation; either > > + version 2.1 of the License, or (at your option) any later > > version. + > > + The GNU C Library is distributed in the hope that it will be > > useful, > > + but WITHOUT ANY WARRANTY; without even the implied warranty of > > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > GNU > > + Lesser General Public License for more details. > > + > > + You should have received a copy of the GNU Lesser General Public > > + License along with the GNU C Library; if not, see > > + <https://www.gnu.org/licenses/>. */ > > + > > +#include <time.h> > > +#include <sys/resource.h> > > +#include <support/check.h> > > +#include <support/timespec.h> > > + > > +#define TST_GETRUSAGE_TIMEOUT 1 > > + > > +static int > > +do_test (void) > > +{ > > + struct timespec tv_then, tv_now, gru_u, gru_s, s, r; > > + struct rusage ru; > > + int ret; > > + > > + tv_then = xclock_now (CLOCK_REALTIME); > > + /* Busy wait for 1 second. */ > > + do > > + { > > + tv_now = xclock_now (CLOCK_REALTIME); > > + r = timespec_sub (tv_now, tv_then); > > + } while ( r.tv_sec != TST_GETRUSAGE_TIMEOUT ); > > What happens if the process stalls for a second? I think that the glibc's test infrastructure will kill it - the default timeout is 2 seconds. As a result the test will fail. > > Andreas. > Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
Hi Andreas, > Hi Andreas, > > > On Mär 15 2021, Lukasz Majewski wrote: > > > > > diff --git a/sysdeps/unix/sysv/linux/tst-getrusage.c > > > b/sysdeps/unix/sysv/linux/tst-getrusage.c new file mode 100644 > > > index 0000000000..068becdadb > > > --- /dev/null > > > +++ b/sysdeps/unix/sysv/linux/tst-getrusage.c > > > @@ -0,0 +1,55 @@ > > > +/* Test for getrusage > > > + Copyright (C) 2021 Free Software Foundation, Inc. > > > + This file is part of the GNU C Library. > > > + > > > + The GNU C Library is free software; you can redistribute it > > > and/or > > > + modify it under the terms of the GNU Lesser General Public > > > + License as published by the Free Software Foundation; either > > > + version 2.1 of the License, or (at your option) any later > > > version. + > > > + The GNU C Library is distributed in the hope that it will be > > > useful, > > > + but WITHOUT ANY WARRANTY; without even the implied warranty of > > > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > > GNU > > > + Lesser General Public License for more details. > > > + > > > + You should have received a copy of the GNU Lesser General > > > Public > > > + License along with the GNU C Library; if not, see > > > + <https://www.gnu.org/licenses/>. */ > > > + > > > +#include <time.h> > > > +#include <sys/resource.h> > > > +#include <support/check.h> > > > +#include <support/timespec.h> > > > + > > > +#define TST_GETRUSAGE_TIMEOUT 1 > > > + > > > +static int > > > +do_test (void) > > > +{ > > > + struct timespec tv_then, tv_now, gru_u, gru_s, s, r; > > > + struct rusage ru; > > > + int ret; > > > + > > > + tv_then = xclock_now (CLOCK_REALTIME); > > > + /* Busy wait for 1 second. */ > > > + do > > > + { > > > + tv_now = xclock_now (CLOCK_REALTIME); > > > + r = timespec_sub (tv_now, tv_then); > > > + } while ( r.tv_sec != TST_GETRUSAGE_TIMEOUT ); > > > > What happens if the process stalls for a second? > > I think that the glibc's test infrastructure will kill it - the > default timeout is 2 seconds. > > As a result the test will fail. On the other hand - the proposed approach with busy waiting was the natural one to check if accounting from getrusage is correct. Maybe you (or anybody else from the community) have a better idea on how to force the process to be "running" (active) for some time? Maybe I could modify the C test code to perform following bash operation: cat /dev/urandom | gzip -9 > /dev/null and replace /dev/urandom with some large (generated in place) file? However, this would pose additional dependencies (gzip) on glibc test suite. > > > > > Andreas. > > > > > > > Best regards, > > Lukasz Majewski > > -- > > DENX Software Engineering GmbH, Managing Director: Wolfgang Denk > HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany > Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: > lukma@denx.de Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
On Mär 17 2021, Lukasz Majewski wrote: > Maybe you (or anybody else from the community) have a better idea on how > to force the process to be "running" (active) for some time? You don't get real-time scheduling on Unix. You always have to account for a process stalling for an arbitrary amount of time. Andreas.
Hi Andreas, > On Mär 17 2021, Lukasz Majewski wrote: > > > Maybe you (or anybody else from the community) have a better idea > > on how to force the process to be "running" (active) for some time? > > > > You don't get real-time scheduling on Unix. You always have to > account for a process stalling for an arbitrary amount of time. > > Andreas. > I'm just looking for ideas on how to reliably test getrusage. Do you have any ideas? Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
On 15/03/2021 07:42, Lukasz Majewski wrote: > This commit adds test to check if getrusage provides correct time > accounting for some busy wait loop. > > To be more specific - the time is measured in a loop by wrappers > from glibc's libsupport and checked if timeout has passed. > > Afterwards, the data from struct rusage, namely ru_stime and ru_utime > is summed up and compared with time from busy waiting. > --- > sysdeps/unix/sysv/linux/Makefile | 2 +- > sysdeps/unix/sysv/linux/tst-getrusage.c | 55 +++++++++++++++++++++++++ > 2 files changed, 56 insertions(+), 1 deletion(-) > create mode 100644 sysdeps/unix/sysv/linux/tst-getrusage.c > > diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile > index 6a45ac820a..a93fa4ca50 100644 > --- a/sysdeps/unix/sysv/linux/Makefile > +++ b/sysdeps/unix/sysv/linux/Makefile > @@ -113,7 +113,7 @@ tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \ > tst-tgkill tst-sysvsem-linux tst-sysvmsg-linux tst-sysvshm-linux \ > tst-timerfd tst-ppoll tst-futimens tst-utime tst-utimes \ > tst-clock_adjtime tst-adjtimex tst-ntp_adjtime tst-futimes \ > - tst-lutimes tst-ntp_gettime tst-ntp_gettimex > + tst-lutimes tst-ntp_gettime tst-ntp_gettimex tst-getrusage > tests-internal += tst-ofdlocks-compat tst-sigcontext-get_pc > tests-time64 += \ > tst-futimes-time64\ > diff --git a/sysdeps/unix/sysv/linux/tst-getrusage.c b/sysdeps/unix/sysv/linux/tst-getrusage.c > new file mode 100644 > index 0000000000..068becdadb > --- /dev/null > +++ b/sysdeps/unix/sysv/linux/tst-getrusage.c > @@ -0,0 +1,55 @@ > +/* Test for getrusage > + Copyright (C) 2021 Free Software Foundation, Inc. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library is distributed in the hope that it will be useful, > + but WITHOUT ANY WARRANTY; without even the implied warranty of > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + <https://www.gnu.org/licenses/>. */ > + > +#include <time.h> > +#include <sys/resource.h> > +#include <support/check.h> > +#include <support/timespec.h> > + > +#define TST_GETRUSAGE_TIMEOUT 1 > + > +static int > +do_test (void) > +{ > + struct timespec tv_then, tv_now, gru_u, gru_s, s, r; > + struct rusage ru; > + int ret; > + > + tv_then = xclock_now (CLOCK_REALTIME); > + /* Busy wait for 1 second. */ > + do > + { > + tv_now = xclock_now (CLOCK_REALTIME); > + r = timespec_sub (tv_now, tv_then); > + } while ( r.tv_sec != TST_GETRUSAGE_TIMEOUT ); > + > + ret = getrusage (RUSAGE_SELF, &ru); > + if (ret == -1) > + FAIL_EXIT1 ("getrusage failed: %m\n"); > + > + gru_u = make_timespec (ru.ru_utime.tv_sec, ru.ru_utime.tv_usec * 1000); > + gru_s = make_timespec (ru.ru_stime.tv_sec, ru.ru_stime.tv_usec * 1000); > + s = timespec_add (gru_u, gru_s); > + > + TEST_COMPARE (support_timespec_check_in_range > + ((struct timespec) { 1, 0 }, s, 0.8, 1.2), 1); > + > + return 0; > +} > + > +#include <support/test-driver.c> > Timer accounting tests are tricky to get right and prone to show a lot of false positive failures and has bitten us in the past (check 04deeaa9ea74 and 9a29f1a2ae3d4b). So I think we should be as simple as possible and take in consideration that tests will run a timer shared machine so even with a busy wait the result timer might not take in consideration the desirable timeout. So for geturage (which afaik is also deprecated on future POSIX) I more simpler tests would be to: 1. Check for invalid 'who' (the EFAULT result from man-pages only trigger where syscall is issued directly, which is not always the case for glibc). 2. Issue getusage and check if the ru_utime.tv_nsec and ru_stime.tv_nsec are within the microseconds range. 3. Do some very short busy wait (10ms) and check if the ru_utime.tv_sec and ru_stime.tv_sec are equal or larger than the previous one. Also, I think this tests should generic, so move to resource folder.
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile index 6a45ac820a..a93fa4ca50 100644 --- a/sysdeps/unix/sysv/linux/Makefile +++ b/sysdeps/unix/sysv/linux/Makefile @@ -113,7 +113,7 @@ tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \ tst-tgkill tst-sysvsem-linux tst-sysvmsg-linux tst-sysvshm-linux \ tst-timerfd tst-ppoll tst-futimens tst-utime tst-utimes \ tst-clock_adjtime tst-adjtimex tst-ntp_adjtime tst-futimes \ - tst-lutimes tst-ntp_gettime tst-ntp_gettimex + tst-lutimes tst-ntp_gettime tst-ntp_gettimex tst-getrusage tests-internal += tst-ofdlocks-compat tst-sigcontext-get_pc tests-time64 += \ tst-futimes-time64\ diff --git a/sysdeps/unix/sysv/linux/tst-getrusage.c b/sysdeps/unix/sysv/linux/tst-getrusage.c new file mode 100644 index 0000000000..068becdadb --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-getrusage.c @@ -0,0 +1,55 @@ +/* Test for getrusage + Copyright (C) 2021 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +#include <time.h> +#include <sys/resource.h> +#include <support/check.h> +#include <support/timespec.h> + +#define TST_GETRUSAGE_TIMEOUT 1 + +static int +do_test (void) +{ + struct timespec tv_then, tv_now, gru_u, gru_s, s, r; + struct rusage ru; + int ret; + + tv_then = xclock_now (CLOCK_REALTIME); + /* Busy wait for 1 second. */ + do + { + tv_now = xclock_now (CLOCK_REALTIME); + r = timespec_sub (tv_now, tv_then); + } while ( r.tv_sec != TST_GETRUSAGE_TIMEOUT ); + + ret = getrusage (RUSAGE_SELF, &ru); + if (ret == -1) + FAIL_EXIT1 ("getrusage failed: %m\n"); + + gru_u = make_timespec (ru.ru_utime.tv_sec, ru.ru_utime.tv_usec * 1000); + gru_s = make_timespec (ru.ru_stime.tv_sec, ru.ru_stime.tv_usec * 1000); + s = timespec_add (gru_u, gru_s); + + TEST_COMPARE (support_timespec_check_in_range + ((struct timespec) { 1, 0 }, s, 0.8, 1.2), 1); + + return 0; +} + +#include <support/test-driver.c>