• Sudeep Holla's avatar
    drivers: base: support cpu cache information interface to userspace via sysfs · 246246cb
    Sudeep Holla authored
    This patch adds initial support for providing processor cache information
    to userspace through sysfs interface. This is based on already existing
    implementations(x86, ia64, s390 and powerpc) and hence the interface is
    intended to be fully compatible.
    The main purpose of this generic support is to avoid further code
    duplication to support new architectures and also to unify all the existing
    different implementations.
    This implementation maintains the hierarchy of cache objects which reflects
    the system's cache topology. Cache devices are instantiated as needed as
    CPUs come online. The cache information is replicated per-cpu even if they are
    shared. A per-cpu array of cache information maintained is used mainly for
    sysfs-related book keeping.
    It also implements the shared_cpu_map attribute, which is essential for
    enabling both kernel and user-space to discover the system's overall cache
    This patch also add the missing ABI documentation for the cacheinfo sysfs
    interface already, which is well defined and widely used.
    Signed-off-by: default avatarSudeep Holla <sudeep.holla@arm.com>
    Reviewed-by: default avatarStephen Boyd <sboyd@codeaurora.org>
    Tested-by: default avatarStephen Boyd <sboyd@codeaurora.org>
    Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Cc: linux-api@vger.kernel.org
    Cc: linux390@de.ibm.com
    Cc: linux-arm-kernel@lists.infradead.org
    Cc: linux-ia64@vger.kernel.org
    Cc: linuxppc-dev@lists.ozlabs.org
    Cc: linux-s390@vger.kernel.org
    Cc: x86@kernel.org
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs-devices-system-cpu 9.56 KB