On 2/3/22 14:37, Claudio Imbrenda wrote:
On Thu, 3 Feb 2022 09:45:56 +0100
Janosch Frank <frankja@xxxxxxxxxxxxx> wrote:
On 1/28/22 19:54, Claudio Imbrenda wrote:
On s390x there are no guarantees about the CPU addresses, except that
they shall be unique. This means that in some environments, it's
possible that there is no match between the CPU address and its
position (index) in the list of available CPUs returned by the system.
While I support this patch set I've yet to find an environment where
this gave me headaches.
This series fixes a small bug in the SMP initialization code, adds a
guarantee that the boot CPU will always have index 0, and introduces
some functions to allow tests to use CPU indexes instead of using
hardcoded CPU addresses. This will allow the tests to run successfully
in more environments (e.g. z/VM, LPAR).
I'm wondering if we should do it the other way round and make the smp_*
functions take a idx instead of a cpu addr. The only instance where this
gets a bit ugly is the sigp calls which we would also need to convert.
yes, in fact this is something I was already planning to do :)
Do you want to add that in a v2 to reduce the additional churn?
for sigp, we can either convert, or add a wrapper with idx.
How about adding a wrapper to smp.c?
smp_cpu_sigp()
smp_cpu_sigp_retry()
That would fall in line with the naming of the smp functions and it's
clear that we refer to a specific cpu from the smp lib.
We can then leave the sigp.h functions as is so Nico can use them for
the invalid addr tests.
Some existing tests are adapted to take advantage of the new
functionalities.
Claudio Imbrenda (5):
lib: s390x: smp: add functions to work with CPU indexes
lib: s390x: smp: guarantee that boot CPU has index 0
s390x: smp: avoid hardcoded CPU addresses
s390x: firq: avoid hardcoded CPU addresses
s390x: skrf: avoid hardcoded CPU addresses
lib/s390x/smp.h | 2 ++
lib/s390x/smp.c | 28 ++++++++++++-----
s390x/firq.c | 17 +++++-----
s390x/skrf.c | 8 +++--
s390x/smp.c | 83 ++++++++++++++++++++++++++-----------------------
5 files changed, 79 insertions(+), 59 deletions(-)
