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2 commits

Author SHA1 Message Date
Pranith Kumar 2141c777f1
util/cacheinfo: Fix warning generated by clang
Clang generates the following warning on aarch64 host:

CC util/cacheinfo.o
/home/pranith/qemu/util/cacheinfo.c:121:48: warning: value size does not match register size specified by the constraint and modifier [-Wasm-operand-widths]
asm volatile("mrs\t%0, ctr_el0" : "=r"(ctr));
^
/home/pranith/qemu/util/cacheinfo.c:121:28: note: use constraint modifier "w"
asm volatile("mrs\t%0, ctr_el0" : "=r"(ctr));
^~
%w0

Constraint modifier 'w' is not (yet?) accepted by gcc. Fix this by increasing the ctr size.

Backports commit 2ae96c157ab3155baf6595c08cf5d3fe3c023a60 from qemu
2018-03-03 22:04:12 -05:00
Emilio G. Cota 8e58c67968
util: add cacheinfo
Add helpers to gather cache info from the host at init-time.

For now, only export the host's I/D cache line sizes, which we
will use to improve cache locality to avoid false sharing.

Backports commit b255b2c8a5484742606e8760870ba3e14d0c9605 from qemu
2018-03-03 16:58:28 -05:00