KVM: Use __print_symbolic() for vmexit tracepoints

The vmexit tracepoints format the exit_reason to make it human-readable.
Since the exit_reason depends on the instruction set (vmx or svm),
formatting is handled with ftrace_print_symbols_seq() by referring to
the appropriate exit reason table.

However, the ftrace_print_symbols_seq() function is not meant to be used
directly in tracepoints since it does not export the formatting table
which userspace tools like trace-cmd and perf use to format traces.

In practice perf dies when formatting vmexit-related events and
trace-cmd falls back to printing the numeric value (with extra
formatting code in the kvm plugin to paper over this limitation).  Other
userspace consumers of vmexit-related tracepoints would be in similar
trouble.

To avoid significant changes to the kvm_exit tracepoint, this patch
moves the vmx and svm exit reason tables into arch/x86/kvm/trace.h and
selects the right table with __print_symbolic() depending on the
instruction set.  Note that __print_symbolic() is designed for exporting
the formatting table to userspace and allows trace-cmd and perf to work.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 0 insertions, 55 deletions

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 6adb7ba13a4a..2b24a88f2c67 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3899,60 +3899,6 @@ static void svm_set_supported_cpuid(u32 func, struct kvm_cpuid_entry2 *entry)
         }
 }
 
-static const struct trace_print_flags svm_exit_reasons_str[] = {
-        { SVM_EXIT_READ_CR0,                    "read_cr0" },
-        { SVM_EXIT_READ_CR3,                    "read_cr3" },
-        { SVM_EXIT_READ_CR4,                    "read_cr4" },
-        { SVM_EXIT_READ_CR8,                    "read_cr8" },
-        { SVM_EXIT_WRITE_CR0,                   "write_cr0" },
-        { SVM_EXIT_WRITE_CR3,                   "write_cr3" },
-        { SVM_EXIT_WRITE_CR4,                   "write_cr4" },
-        { SVM_EXIT_WRITE_CR8,                   "write_cr8" },
-        { SVM_EXIT_READ_DR0,                    "read_dr0" },
-        { SVM_EXIT_READ_DR1,                    "read_dr1" },
-        { SVM_EXIT_READ_DR2,                    "read_dr2" },
-        { SVM_EXIT_READ_DR3,                    "read_dr3" },
-        { SVM_EXIT_WRITE_DR0,                   "write_dr0" },
-        { SVM_EXIT_WRITE_DR1,                   "write_dr1" },
-        { SVM_EXIT_WRITE_DR2,                   "write_dr2" },
-        { SVM_EXIT_WRITE_DR3,                   "write_dr3" },
-        { SVM_EXIT_WRITE_DR5,                   "write_dr5" },
-        { SVM_EXIT_WRITE_DR7,                   "write_dr7" },
-        { SVM_EXIT_EXCP_BASE + DB_VECTOR,       "DB excp" },
-        { SVM_EXIT_EXCP_BASE + BP_VECTOR,       "BP excp" },
-        { SVM_EXIT_EXCP_BASE + UD_VECTOR,       "UD excp" },
-        { SVM_EXIT_EXCP_BASE + PF_VECTOR,       "PF excp" },
-        { SVM_EXIT_EXCP_BASE + NM_VECTOR,       "NM excp" },
-        { SVM_EXIT_EXCP_BASE + MC_VECTOR,       "MC excp" },
-        { SVM_EXIT_INTR,                        "interrupt" },
-        { SVM_EXIT_NMI,                         "nmi" },
-        { SVM_EXIT_SMI,                         "smi" },
-        { SVM_EXIT_INIT,                        "init" },
-        { SVM_EXIT_VINTR,                       "vintr" },
-        { SVM_EXIT_CPUID,                       "cpuid" },
-        { SVM_EXIT_INVD,                        "invd" },
-        { SVM_EXIT_HLT,                         "hlt" },
-        { SVM_EXIT_INVLPG,                      "invlpg" },
-        { SVM_EXIT_INVLPGA,                     "invlpga" },
-        { SVM_EXIT_IOIO,                        "io" },
-        { SVM_EXIT_MSR,                         "msr" },
-        { SVM_EXIT_TASK_SWITCH,                 "task_switch" },
-        { SVM_EXIT_SHUTDOWN,                    "shutdown" },
-        { SVM_EXIT_VMRUN,                       "vmrun" },
-        { SVM_EXIT_VMMCALL,                     "hypercall" },
-        { SVM_EXIT_VMLOAD,                      "vmload" },
-        { SVM_EXIT_VMSAVE,                      "vmsave" },
-        { SVM_EXIT_STGI,                        "stgi" },
-        { SVM_EXIT_CLGI,                        "clgi" },
-        { SVM_EXIT_SKINIT,                      "skinit" },
-        { SVM_EXIT_WBINVD,                      "wbinvd" },
-        { SVM_EXIT_MONITOR,                     "monitor" },
-        { SVM_EXIT_MWAIT,                       "mwait" },
-        { SVM_EXIT_XSETBV,                      "xsetbv" },
-        { SVM_EXIT_NPF,                         "npf" },
-        { -1, NULL }
-};
-
 static int svm_get_lpage_level(void)
 {
         return PT_PDPE_LEVEL;
@@ -4225,7 +4171,6 @@ static struct kvm_x86_ops svm_x86_ops = {
         .get_mt_mask = svm_get_mt_mask,
 
         .get_exit_info = svm_get_exit_info,
-        .exit_reasons_str = svm_exit_reasons_str,
 
         .get_lpage_level = svm_get_lpage_level,