From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: [PATCH 5/8] ARM: KVM: Switch the CP reg search to be a binary search Date: Mon, 8 Feb 2016 11:40:19 +0000 Message-ID: <1454931622-14902-6-git-send-email-marc.zyngier@arm.com> References: <1454931622-14902-1-git-send-email-marc.zyngier@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu To: Christoffer Dall Return-path: In-Reply-To: <1454931622-14902-1-git-send-email-marc.zyngier@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org Doing a linear search is a bit silly when we can do a binary search. Not that we trap that so many things that it has become a burden yet, but it makes sense to align it with the arm64 code. Signed-off-by: Marc Zyngier --- arch/arm/kvm/coproc.c | 41 +++++++++++++++++++++++------------------ 1 file changed, 23 insertions(+), 18 deletions(-) diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c index 2a67f00..4f1c869 100644 --- a/arch/arm/kvm/coproc.c +++ b/arch/arm/kvm/coproc.c @@ -16,6 +16,8 @@ * along with this program; if not, write to the Free Software * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +#include #include #include #include @@ -414,29 +416,32 @@ static const struct coproc_reg *get_target_table(unsigned target, size_t *num) return table->table; } +#define reg_to_match_value(x) \ + ({ \ + unsigned long val; \ + val = (x)->CRn << 11; \ + val |= (x)->CRm << 7; \ + val |= (x)->Op1 << 4; \ + val |= (x)->Op2 << 1; \ + val |= !(x)->is_64bit; \ + val; \ + }) + +static int match_reg(const void *key, const void *elt) +{ + const unsigned long pval = (unsigned long)key; + const struct coproc_reg *r = elt; + + return pval - reg_to_match_value(r); +} + static const struct coproc_reg *find_reg(const struct coproc_params *params, const struct coproc_reg table[], unsigned int num) { - unsigned int i; - - for (i = 0; i < num; i++) { - const struct coproc_reg *r = &table[i]; + unsigned long pval = reg_to_match_value(params); - if (params->is_64bit != r->is_64bit) - continue; - if (params->CRn != r->CRn) - continue; - if (params->CRm != r->CRm) - continue; - if (params->Op1 != r->Op1) - continue; - if (params->Op2 != r->Op2) - continue; - - return r; - } - return NULL; + return bsearch((void *)pval, table, num, sizeof(table[0]), match_reg); } static int emulate_cp15(struct kvm_vcpu *vcpu, -- 2.1.4