Commit 6e1cce7c authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: selftests: Add __open_path_or_exit() variant to provide extra help info 

Add an inner __open_path_or_exit() API to let the caller provide additional
information on ENOENT to try and help the user figure out why the test is
being skipped, e.g. for files like the page_idle bitmap needed by the
access tracking perf, which is dependent on a Kconfig.

Immediately convert /dev/kvm to the new API, both as an example and because
users might not know that some architectures/setups require loading KVM.

Link: https://lore.kernel.org/r/20250516215909.2551628-3-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent fcab107a

tools/testing/selftests/kvm/include/kvm_util.h

+1 −0
Original line number Diff line number Diff line
@@ -253,6 +253,7 @@ struct vm_guest_mode_params { 
};

extern const struct vm_guest_mode_params vm_guest_mode_params[];



int __open_path_or_exit(const char *path, int flags, const char *enoent_help);

int open_path_or_exit(const char *path, int flags);

int open_kvm_dev_path_or_exit(void);

tools/testing/selftests/kvm/lib/kvm_util.c

+15 −4
Original line number Diff line number Diff line
@@ -26,15 +26,26 @@ static uint32_t last_guest_seed; 


static int vcpu_mmap_sz(void);



int open_path_or_exit(const char *path, int flags)

int __open_path_or_exit(const char *path, int flags, const char *enoent_help)

{

	int fd;



	fd = open(path, flags);

	__TEST_REQUIRE(fd >= 0 || errno != ENOENT, "Cannot open %s: %s", path, strerror(errno));

	TEST_ASSERT(fd >= 0, "Failed to open '%s'", path);

	if (fd < 0)

		goto error;



	return fd;



error:

	if (errno == ENOENT)

		ksft_exit_skip("- Cannot open '%s': %s.  %s\n",

			       path, strerror(errno), enoent_help);

	TEST_FAIL("Failed to open '%s'", path);

}



int open_path_or_exit(const char *path, int flags)

{

	return __open_path_or_exit(path, flags, "");

}



/*
@@ -48,7 +59,7 @@ int open_path_or_exit(const char *path, int flags) 
 */

static int _open_kvm_dev_path_or_exit(int flags)

{

	return open_path_or_exit(KVM_DEV_PATH, flags);

	return __open_path_or_exit(KVM_DEV_PATH, flags, "Is KVM loaded and enabled?");

}



int open_kvm_dev_path_or_exit(void)