Re: [PATCH v1 5/9] selftests: kvm: s390: Add debug print functions

On Tue, 9 Jul 2024 14:57:00 +0200 Christoph Schlameuss schlameuss@linux.ibm.com wrote:

Add functions to simply print some basic state information in selftests.

The output can be enabled by setting:

#define TH_LOG_ENABLED 1
#define DEBUG 1

• print_psw: current SIE state description and VM run state
• print_hex_bytes: print memory with some counting markers
• print_hex: PRINT_HEX with 512 bytes
• print_run: use print_psw and print_hex to print contents of VM run state and SIE state description
• print_regs: print content of general and control registers

All prints use pr_debug for the output and can be configured using DEBUG.

Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com

.../selftests/kvm/include/s390x/debug_print.h | 78 +++++++++++++++++++ .../selftests/kvm/s390x/ucontrol_test.c | 1 + 2 files changed, 79 insertions(+) create mode 100644 tools/testing/selftests/kvm/include/s390x/debug_print.h

diff --git a/tools/testing/selftests/kvm/include/s390x/debug_print.h b/tools/testing/selftests/kvm/include/s390x/debug_print.h new file mode 100644 index 000000000000..7cc21596398e --- /dev/null +++ b/tools/testing/selftests/kvm/include/s390x/debug_print.h @@ -0,0 +1,78 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/*

• • Definition for kernel virtual machines on s390x
• • Copyright IBM Corp. 2024
• • Authors:
• • Christoph Schlameuss schlameuss@linux.ibm.com
• */

+#ifndef SELFTEST_KVM_DEBUG_PRINT_H +#define SELFTEST_KVM_DEBUG_PRINT_H

+#include "kvm_util.h" +#include "sie.h"

+static inline void print_hex_bytes(const char *name, u64 page, size_t len)

"page" is not an appropriate name, it's just an address, right? "addr" seems a more appropriate name

+{

• pr_debug("%s (%p)\t\t8-0x08 12-0x0c 16-0x10 20-0x14 24-0x18 28-0x1c",

•  name, (void *)page);
  

• for (u8 pp_row = 0; pp_row < (len / 32); pp_row++) {

• pr_debug("\n %3d 0x%.3x ", pp_row * 32, pp_row * 32);
  

• for (u8 pp_block = 0; pp_block < 8; pp_block++)
  

• 	pr_debug(" %8x", *(((u32 *)page) + 8 * pp_row + pp_block));
  

why not printing in blocks of 64 bits?

• }
• pr_debug("\n");

+}

+static inline void print_hex(const char *name, u64 page)

same here s/page/addr/

+{

• print_hex_bytes(name, page, 512);

+}

+static inline void print_psw(struct kvm_run *run, struct kvm_s390_sie_block *sie_block) +{

• pr_debug("flags:0x%x psw:0x%.16llx:0x%.16llx exit:%u %s\n",

•  run->flags,
  

•  run->psw_mask, run->psw_addr,
  

•  run->exit_reason, exit_reason_str(run->exit_reason));
  

• pr_debug("sie_block psw:0x%.16llx:0x%.16llx\n",

•  sie_block->psw_mask, sie_block->psw_addr);
  

+}

+static inline void print_run(struct kvm_run *run, struct kvm_s390_sie_block *sie_block) +{

• print_hex("run", (u64)run);
• print_hex("sie_block", (u64)sie_block);
• print_psw(run, sie_block);

+}

+static inline void print_regs(int vcpu_fd) +{

• struct kvm_sregs sregs = {};
• struct kvm_regs regs = {};
• int i;
• if (ioctl(vcpu_fd, KVM_GET_REGS, &regs) != 0)

• TEST_FAIL("get regs failed, %s", strerror(errno));
  

• pr_debug("gprs:\n");

if you rewrite print_hex_bytes to print blocks of 8 bytes, you can reuse it here:

• for (i = 0; i < 16; i += 4)

• pr_debug("0x%.16llx 0x%.16llx 0x%.16llx 0x%.16llx\n",
  

• 	 regs.gprs[i], regs.gprs[i + 1],
  

• 	 regs.gprs[i + 2], regs.gprs[i + 3]);
  

• if (ioctl(vcpu_fd, KVM_GET_SREGS, &sregs) != 0)

• TEST_FAIL("get sregs failed, %s", strerror(errno));
  

• pr_debug("acrs:\n");

acrs are 32 bits, you can print twice as many per row:

• for (i = 0; i < 16; i += 4)

• pr_debug("0x%.8x 0x%.8x 0x%.8x 0x%.8x\n",
  

• 	 sregs.acrs[i], sregs.acrs[i + 1],
  

• 	 sregs.acrs[i + 2], sregs.acrs[i + 3]);
  

• pr_debug("crs:\n");

and here you could reuse print_hex_bytes:

• for (i = 0; i < 16; i += 4)

• pr_debug("0x%.16llx 0x%.16llx 0x%.16llx 0x%.16llx\n",
  

• 	 sregs.crs[i], sregs.crs[i + 1],
  

• 	 sregs.crs[i + 2], sregs.crs[i + 3]);
  

+}

+#endif /* SELFTEST_KVM_DEBUG_PRINT_H */ diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c b/tools/testing/selftests/kvm/s390x/ucontrol_test.c index 44945af6d47d..5c009ee27fd2 100644 --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c @@ -7,6 +7,7 @@

• Authors:
• Christoph Schlameuss schlameuss@linux.ibm.com

*/ +#include "debug_print.h" #include "kselftest_harness.h" #include "kvm_util.h" #include "processor.h"