Commit d06a5440 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

ARM: KVM: Switch the CP reg search to be a binary search 



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.

Reviewed-by: default avatarChristoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
parent f1d67d4a

arch/arm/kvm/coproc.c

+23 −18
Original line number Diff line number Diff line
@@ -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 <linux/bsearch.h>

#include <linux/mm.h>

#include <linux/kvm_host.h>

#include <linux/uaccess.h>
@@ -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;

	unsigned long pval = reg_to_match_value(params);



	for (i = 0; i < num; i++) {

		const struct coproc_reg *r = &table[i];



		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,

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