This adds an implementation of a simple L2 configuration, in which a
unified L2 cache (stores both blocks of instructions and data) is
maintained for each core separately, with no inter-core interaction
taken in account. The L2 cache is used as a backup for L1 and is only
accessed if the wanted block does not exist in L1.
In terms of multi-threaded user-space emulation, the same approximation
of L1 is done, a static number of caches is maintained, and each and
every memory access initiated by a thread will have to go through one of
the available caches.
An atomic increment is used to maintain the number of L2 misses per
instruction.
The default cache parameters of L2 caches is:
2MB cache size
16-way associativity
64-byte blocks
Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210810134844.166490-3-ma.mandourr@gmail.com>
Message-Id: <20211026102234.3961636-15-alex.bennee@linaro.org>
Multicore L1 cache modelling is introduced and is supported for both
full system emulation and linux-user.
For full-system emulation, L1 icache and dcache are maintained for each
available core, since this information is exposed to the plugin through
`qemu_plugin_n_vcpus()`.
For linux-user, a static number of cores is assumed (default 1 core, and
can be provided as a plugin argument `cores=N`). Every memory access
goes through one of these caches, this approach is taken as it's
somewhat akin to what happens on real setup, where a program that
dispatches more threads than the available cores, they'll thrash
each other
Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
Message-Id: <20210803151301.123581-2-ma.mandourr@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
