| Message ID | 20200117104640.1983-8-frankja@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | s390x: smp: Improve smp code and reset checks | expand |
On Fri, 17 Jan 2020 05:46:38 -0500 Janosch Frank <frankja@linux.ibm.com> wrote: > Now that we have a loop which is executed after we return from the > main function of a secondary cpu, we can remove the surplus loops. > > Signed-off-by: Janosch Frank <frankja@linux.ibm.com> > --- > s390x/smp.c | 8 +------- > 1 file changed, 1 insertion(+), 7 deletions(-) > > diff --git a/s390x/smp.c b/s390x/smp.c > index 555ed72..c12a3db 100644 > --- a/s390x/smp.c > +++ b/s390x/smp.c > @@ -29,15 +29,9 @@ static void wait_for_flag(void) > } > } > > -static void cpu_loop(void) > -{ > - for (;;) {} > -} > - > static void test_func(void) > { > testflag = 1; > - cpu_loop(); > } > > static void test_start(void) > @@ -234,7 +228,7 @@ int main(void) > > /* Setting up the cpu to give it a stack and lowcore */ > psw.mask = extract_psw_mask(); > - psw.addr = (unsigned long)cpu_loop; > + psw.addr = (unsigned long)test_func; Before, you did not set testflag here... intended change? > smp_cpu_setup(1, psw); > smp_cpu_stop(1); >
On 1/20/20 12:29 PM, Cornelia Huck wrote: > On Fri, 17 Jan 2020 05:46:38 -0500 > Janosch Frank <frankja@linux.ibm.com> wrote: > >> Now that we have a loop which is executed after we return from the >> main function of a secondary cpu, we can remove the surplus loops. >> >> Signed-off-by: Janosch Frank <frankja@linux.ibm.com> >> --- >> s390x/smp.c | 8 +------- >> 1 file changed, 1 insertion(+), 7 deletions(-) >> >> diff --git a/s390x/smp.c b/s390x/smp.c >> index 555ed72..c12a3db 100644 >> --- a/s390x/smp.c >> +++ b/s390x/smp.c >> @@ -29,15 +29,9 @@ static void wait_for_flag(void) >> } >> } >> >> -static void cpu_loop(void) >> -{ >> - for (;;) {} >> -} >> - >> static void test_func(void) >> { >> testflag = 1; >> - cpu_loop(); >> } >> >> static void test_start(void) >> @@ -234,7 +228,7 @@ int main(void) >> >> /* Setting up the cpu to give it a stack and lowcore */ >> psw.mask = extract_psw_mask(); >> - psw.addr = (unsigned long)cpu_loop; >> + psw.addr = (unsigned long)test_func; > > Before, you did not set testflag here... intended change? Yes It is set to 0 before the first test, so it shouldn't matter. > >> smp_cpu_setup(1, psw); >> smp_cpu_stop(1); >> >
On Mon, 20 Jan 2020 15:41:52 +0100 Janosch Frank <frankja@linux.ibm.com> wrote: > On 1/20/20 12:29 PM, Cornelia Huck wrote: > > On Fri, 17 Jan 2020 05:46:38 -0500 > > Janosch Frank <frankja@linux.ibm.com> wrote: > > > >> Now that we have a loop which is executed after we return from the > >> main function of a secondary cpu, we can remove the surplus loops. > >> > >> Signed-off-by: Janosch Frank <frankja@linux.ibm.com> > >> --- > >> s390x/smp.c | 8 +------- > >> 1 file changed, 1 insertion(+), 7 deletions(-) > >> > >> diff --git a/s390x/smp.c b/s390x/smp.c > >> index 555ed72..c12a3db 100644 > >> --- a/s390x/smp.c > >> +++ b/s390x/smp.c > >> @@ -29,15 +29,9 @@ static void wait_for_flag(void) > >> } > >> } > >> > >> -static void cpu_loop(void) > >> -{ > >> - for (;;) {} > >> -} > >> - > >> static void test_func(void) > >> { > >> testflag = 1; > >> - cpu_loop(); > >> } > >> > >> static void test_start(void) > >> @@ -234,7 +228,7 @@ int main(void) > >> > >> /* Setting up the cpu to give it a stack and lowcore */ > >> psw.mask = extract_psw_mask(); > >> - psw.addr = (unsigned long)cpu_loop; > >> + psw.addr = (unsigned long)test_func; > > > > Before, you did not set testflag here... intended change? > > Yes > It is set to 0 before the first test, so it shouldn't matter. Hm... I got a bit lost in all those changes, so I checked your branch on github, and I don't see it being set to 0 before test_start() is called? > > > > >> smp_cpu_setup(1, psw); > >> smp_cpu_stop(1); > >> > > > >
On 1/20/20 5:11 PM, Cornelia Huck wrote: > On Mon, 20 Jan 2020 15:41:52 +0100 > Janosch Frank <frankja@linux.ibm.com> wrote: > >> On 1/20/20 12:29 PM, Cornelia Huck wrote: >>> On Fri, 17 Jan 2020 05:46:38 -0500 >>> Janosch Frank <frankja@linux.ibm.com> wrote: >>> >>>> Now that we have a loop which is executed after we return from the >>>> main function of a secondary cpu, we can remove the surplus loops. >>>> >>>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com> >>>> --- >>>> s390x/smp.c | 8 +------- >>>> 1 file changed, 1 insertion(+), 7 deletions(-) >>>> >>>> diff --git a/s390x/smp.c b/s390x/smp.c >>>> index 555ed72..c12a3db 100644 >>>> --- a/s390x/smp.c >>>> +++ b/s390x/smp.c >>>> @@ -29,15 +29,9 @@ static void wait_for_flag(void) >>>> } >>>> } >>>> >>>> -static void cpu_loop(void) >>>> -{ >>>> - for (;;) {} >>>> -} >>>> - >>>> static void test_func(void) >>>> { >>>> testflag = 1; >>>> - cpu_loop(); >>>> } >>>> >>>> static void test_start(void) >>>> @@ -234,7 +228,7 @@ int main(void) >>>> >>>> /* Setting up the cpu to give it a stack and lowcore */ >>>> psw.mask = extract_psw_mask(); >>>> - psw.addr = (unsigned long)cpu_loop; >>>> + psw.addr = (unsigned long)test_func; >>> >>> Before, you did not set testflag here... intended change? >> >> Yes >> It is set to 0 before the first test, so it shouldn't matter. > > Hm... I got a bit lost in all those changes, so I checked your branch > on github, and I don't see it being set to 0 before test_start() is > called? Well, that's because test_start doesn't care about the flag. ecall and emcall are the first users, and they set it to 0 before using it. > >> >>> >>>> smp_cpu_setup(1, psw); >>>> smp_cpu_stop(1); >>>> >>> >> >> >
On Tue, 21 Jan 2020 13:46:51 +0100 Janosch Frank <frankja@linux.ibm.com> wrote: > On 1/20/20 5:11 PM, Cornelia Huck wrote: > > On Mon, 20 Jan 2020 15:41:52 +0100 > > Janosch Frank <frankja@linux.ibm.com> wrote: > > > >> On 1/20/20 12:29 PM, Cornelia Huck wrote: > >>> On Fri, 17 Jan 2020 05:46:38 -0500 > >>> Janosch Frank <frankja@linux.ibm.com> wrote: > >>> > >>>> Now that we have a loop which is executed after we return from the > >>>> main function of a secondary cpu, we can remove the surplus loops. > >>>> > >>>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com> > >>>> --- > >>>> s390x/smp.c | 8 +------- > >>>> 1 file changed, 1 insertion(+), 7 deletions(-) > >>>> > >>>> diff --git a/s390x/smp.c b/s390x/smp.c > >>>> index 555ed72..c12a3db 100644 > >>>> --- a/s390x/smp.c > >>>> +++ b/s390x/smp.c > >>>> @@ -29,15 +29,9 @@ static void wait_for_flag(void) > >>>> } > >>>> } > >>>> > >>>> -static void cpu_loop(void) > >>>> -{ > >>>> - for (;;) {} > >>>> -} > >>>> - > >>>> static void test_func(void) > >>>> { > >>>> testflag = 1; > >>>> - cpu_loop(); > >>>> } > >>>> > >>>> static void test_start(void) > >>>> @@ -234,7 +228,7 @@ int main(void) > >>>> > >>>> /* Setting up the cpu to give it a stack and lowcore */ > >>>> psw.mask = extract_psw_mask(); > >>>> - psw.addr = (unsigned long)cpu_loop; > >>>> + psw.addr = (unsigned long)test_func; > >>> > >>> Before, you did not set testflag here... intended change? > >> > >> Yes > >> It is set to 0 before the first test, so it shouldn't matter. > > > > Hm... I got a bit lost in all those changes, so I checked your branch > > on github, and I don't see it being set to 0 before test_start() is > > called? > > Well, that's because test_start doesn't care about the flag. But I see a wait_for_flag() in there? What am I missing? > ecall and emcall are the first users, and they set it to 0 before using it. > > > > >> > >>> > >>>> smp_cpu_setup(1, psw); > >>>> smp_cpu_stop(1); > >>>> > >>> > >> > >> > > > >
On 1/21/20 1:59 PM, Cornelia Huck wrote: > On Tue, 21 Jan 2020 13:46:51 +0100 > Janosch Frank <frankja@linux.ibm.com> wrote: > >> On 1/20/20 5:11 PM, Cornelia Huck wrote: >>> On Mon, 20 Jan 2020 15:41:52 +0100 >>> Janosch Frank <frankja@linux.ibm.com> wrote: >>> >>>> On 1/20/20 12:29 PM, Cornelia Huck wrote: >>>>> On Fri, 17 Jan 2020 05:46:38 -0500 >>>>> Janosch Frank <frankja@linux.ibm.com> wrote: >>>>> >>>>>> Now that we have a loop which is executed after we return from the >>>>>> main function of a secondary cpu, we can remove the surplus loops. >>>>>> >>>>>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com> >>>>>> --- >>>>>> s390x/smp.c | 8 +------- >>>>>> 1 file changed, 1 insertion(+), 7 deletions(-) >>>>>> >>>>>> diff --git a/s390x/smp.c b/s390x/smp.c >>>>>> index 555ed72..c12a3db 100644 >>>>>> --- a/s390x/smp.c >>>>>> +++ b/s390x/smp.c >>>>>> @@ -29,15 +29,9 @@ static void wait_for_flag(void) >>>>>> } >>>>>> } >>>>>> >>>>>> -static void cpu_loop(void) >>>>>> -{ >>>>>> - for (;;) {} >>>>>> -} >>>>>> - >>>>>> static void test_func(void) >>>>>> { >>>>>> testflag = 1; >>>>>> - cpu_loop(); >>>>>> } >>>>>> >>>>>> static void test_start(void) >>>>>> @@ -234,7 +228,7 @@ int main(void) >>>>>> >>>>>> /* Setting up the cpu to give it a stack and lowcore */ >>>>>> psw.mask = extract_psw_mask(); >>>>>> - psw.addr = (unsigned long)cpu_loop; >>>>>> + psw.addr = (unsigned long)test_func; >>>>> >>>>> Before, you did not set testflag here... intended change? >>>> >>>> Yes >>>> It is set to 0 before the first test, so it shouldn't matter. >>> >>> Hm... I got a bit lost in all those changes, so I checked your branch >>> on github, and I don't see it being set to 0 before test_start() is >>> called? >> >> Well, that's because test_start doesn't care about the flag. > > But I see a wait_for_flag() in there? What am I missing? > >> ecall and emcall are the first users, and they set it to 0 before using it. Well, cpu #1 will update tesflag to 1 in ecall() and emcall() >> >>> >>>> >>>>> >>>>>> smp_cpu_setup(1, psw); >>>>>> smp_cpu_stop(1); >>>>>> >>>>> >>>> >>>> >>> >> >> >
diff --git a/s390x/smp.c b/s390x/smp.c index 555ed72..c12a3db 100644 --- a/s390x/smp.c +++ b/s390x/smp.c @@ -29,15 +29,9 @@ static void wait_for_flag(void) } } -static void cpu_loop(void) -{ - for (;;) {} -} - static void test_func(void) { testflag = 1; - cpu_loop(); } static void test_start(void) @@ -234,7 +228,7 @@ int main(void) /* Setting up the cpu to give it a stack and lowcore */ psw.mask = extract_psw_mask(); - psw.addr = (unsigned long)cpu_loop; + psw.addr = (unsigned long)test_func; smp_cpu_setup(1, psw); smp_cpu_stop(1);
Now that we have a loop which is executed after we return from the main function of a secondary cpu, we can remove the surplus loops. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> --- s390x/smp.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-)