Message ID | 1421144560-15901-10-git-send-email-khandual@linux.vnet.ibm.com (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | Michael Ellerman |
Headers | show |
On 01/13/2015 03:22 AM, Anshuman Khandual wrote: > This patch adds a test to verify that the changed DSCR value inside > any process would be inherited to it's child process across the fork > system call. > > Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> > --- > tools/testing/selftests/powerpc/dscr/Makefile | 3 +- > .../selftests/powerpc/dscr/dscr_inherit_test.c | 96 ++++++++++++++++++++++ > 2 files changed, 98 insertions(+), 1 deletion(-) > create mode 100644 tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c > > diff --git a/tools/testing/selftests/powerpc/dscr/Makefile b/tools/testing/selftests/powerpc/dscr/Makefile > index ae865d8..81239e2 100644 > --- a/tools/testing/selftests/powerpc/dscr/Makefile > +++ b/tools/testing/selftests/powerpc/dscr/Makefile > @@ -1,4 +1,5 @@ > -PROGS := dscr_default_test dscr_explicit_test dscr_user_test > +PROGS := dscr_default_test dscr_explicit_test dscr_user_test \ > + dscr_inherit_test > > CFLAGS := $(CFLAGS) -lpthread > > diff --git a/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c b/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c > new file mode 100644 > index 0000000..f1add77 > --- /dev/null > +++ b/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c > @@ -0,0 +1,96 @@ > +/* > + * POWER Data Stream Control Register (DSCR) fork test > + * > + * This testcase modifies the DSCR using mtspr, forks and then > + * verifies that the child process has the correct changed DSCR > + * value using mfspr. > + * > + * When using the privilege state SPR, the instructions such as > + * mfspr or mtspr are priviledged and the kernel emulates them > + * for us. Instructions using problem state SPR can be exuecuted > + * directly without any emulation if the HW supports them. Else > + * they also get emulated by the kernel. > + * > + * Copyright (C) 2012 Anton Blanchard <anton@au.ibm.com>, IBM > + * Copyright (C) 2015 Anshuman Khandual <khandual@linux.vnet.ibm.com>, 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. > + */ > +#include "dscr.h" > + > +int test_body(void) > +{ > + unsigned long i, dscr = 0; > + pid_t pid; > + > + srand(getpid()); > + set_dscr(dscr); > + > + for (i = 0; i < COUNT; i++) { > + unsigned long cur_dscr, cur_dscr_usr; > + > + dscr++; > + if (dscr > DSCR_MAX) > + dscr = 0; > + > + if (i % 2 == 0) > + set_dscr_usr(dscr); > + else > + set_dscr(dscr); > + > + /* > + * XXX: Force a context switch out so that DSCR > + * current value is copied into the thread struct > + * which is required for the child to inherit the > + * changed value. > + */ > + sleep(1); > + > + pid = fork(); > + if (pid == -1) { > + perror("fork() failed\n"); > + exit(1); > + } else if (pid) { > + int status; > + > + if (waitpid(pid, &status, 0) == -1) { > + perror("waitpid() failed\n"); > + exit(1); > + } > + > + if (!WIFEXITED(status)) { > + fprintf(stderr, "Child didn't exit cleanly\n"); > + exit(1); > + } > + > + if (WEXITSTATUS(status) != 0) { > + fprintf(stderr, "Child didn't exit cleanly\n"); > + return 1; > + } > + } else { > + cur_dscr = get_dscr(); > + if (cur_dscr != dscr) { > + fprintf(stderr, "Kernel DSCR should be %ld " > + "but is %ld\n", dscr, cur_dscr); > + exit(1); > + } > + > + cur_dscr_usr = get_dscr_usr(); > + if (cur_dscr_usr != dscr) { > + fprintf(stderr, "User DSCR should be %ld " > + "but is %ld\n", dscr, cur_dscr_usr); > + exit(1); > + } > + exit(0); > + } > + } > + return 0; > +} > + > +int main(int argc, char *argv[]) > +{ > + return test_harness(test_body, "dscr_inherit_test"); > +} > Could you please add a .gitignore for powerpc targets as we discussed earlier. It can be separate patch. Also, I would like to see the test results reports using kselftest.h - it can be separate patch in the interest of getting tests in. Acked-by: Shuah Khan <shuahkh@osg.samsung.com> Please take this through powerpc maintainer git. thanks, -- Shuah
diff --git a/tools/testing/selftests/powerpc/dscr/Makefile b/tools/testing/selftests/powerpc/dscr/Makefile index ae865d8..81239e2 100644 --- a/tools/testing/selftests/powerpc/dscr/Makefile +++ b/tools/testing/selftests/powerpc/dscr/Makefile @@ -1,4 +1,5 @@ -PROGS := dscr_default_test dscr_explicit_test dscr_user_test +PROGS := dscr_default_test dscr_explicit_test dscr_user_test \ + dscr_inherit_test CFLAGS := $(CFLAGS) -lpthread diff --git a/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c b/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c new file mode 100644 index 0000000..f1add77 --- /dev/null +++ b/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c @@ -0,0 +1,96 @@ +/* + * POWER Data Stream Control Register (DSCR) fork test + * + * This testcase modifies the DSCR using mtspr, forks and then + * verifies that the child process has the correct changed DSCR + * value using mfspr. + * + * When using the privilege state SPR, the instructions such as + * mfspr or mtspr are priviledged and the kernel emulates them + * for us. Instructions using problem state SPR can be exuecuted + * directly without any emulation if the HW supports them. Else + * they also get emulated by the kernel. + * + * Copyright (C) 2012 Anton Blanchard <anton@au.ibm.com>, IBM + * Copyright (C) 2015 Anshuman Khandual <khandual@linux.vnet.ibm.com>, 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. + */ +#include "dscr.h" + +int test_body(void) +{ + unsigned long i, dscr = 0; + pid_t pid; + + srand(getpid()); + set_dscr(dscr); + + for (i = 0; i < COUNT; i++) { + unsigned long cur_dscr, cur_dscr_usr; + + dscr++; + if (dscr > DSCR_MAX) + dscr = 0; + + if (i % 2 == 0) + set_dscr_usr(dscr); + else + set_dscr(dscr); + + /* + * XXX: Force a context switch out so that DSCR + * current value is copied into the thread struct + * which is required for the child to inherit the + * changed value. + */ + sleep(1); + + pid = fork(); + if (pid == -1) { + perror("fork() failed\n"); + exit(1); + } else if (pid) { + int status; + + if (waitpid(pid, &status, 0) == -1) { + perror("waitpid() failed\n"); + exit(1); + } + + if (!WIFEXITED(status)) { + fprintf(stderr, "Child didn't exit cleanly\n"); + exit(1); + } + + if (WEXITSTATUS(status) != 0) { + fprintf(stderr, "Child didn't exit cleanly\n"); + return 1; + } + } else { + cur_dscr = get_dscr(); + if (cur_dscr != dscr) { + fprintf(stderr, "Kernel DSCR should be %ld " + "but is %ld\n", dscr, cur_dscr); + exit(1); + } + + cur_dscr_usr = get_dscr_usr(); + if (cur_dscr_usr != dscr) { + fprintf(stderr, "User DSCR should be %ld " + "but is %ld\n", dscr, cur_dscr_usr); + exit(1); + } + exit(0); + } + } + return 0; +} + +int main(int argc, char *argv[]) +{ + return test_harness(test_body, "dscr_inherit_test"); +}
This patch adds a test to verify that the changed DSCR value inside any process would be inherited to it's child process across the fork system call. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> --- tools/testing/selftests/powerpc/dscr/Makefile | 3 +- .../selftests/powerpc/dscr/dscr_inherit_test.c | 96 ++++++++++++++++++++++ 2 files changed, 98 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c