[3/4] plugins/execlog: add data address match

Commit Message

Sven Schnelle Feb. 28, 2024, 8:02 p.m. UTC

Add a match similar to the afilter address match, but for data
addresses. When an address is specified with '-dfilter=0x12345'
only load/stores to/from address 0x12345 are printed. All other
instructions are hidden.

Signed-off-by: Sven Schnelle <[e-mail]>
---
 contrib/plugins/execlog.c | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

Patch

diff --git a/contrib/plugins/execlog.c b/contrib/plugins/execlog.c
index b4b5ba113c..33fef9bfc6 100644
--- a/contrib/plugins/execlog.c
+++ b/contrib/plugins/execlog.c
@@ -23,9 +23,11 @@  static GRWLock expand_array_lock;
 
 static GPtrArray *imatches;
 static GArray *amatches;
+static GArray *dmatches;
 
 struct execlog_ctx {
     GString *s;
+    bool log;
 };
 
 /*
@@ -45,6 +47,17 @@  static void expand_last_exec(int cpu_index)
     g_rw_lock_writer_unlock(&expand_array_lock);
 }
 
+static bool match_vaddr(struct execlog_ctx *ctx, uint64_t vaddr)
+{
+    for (int i = 0; i < dmatches->len; i++) {
+        uint64_t v = g_array_index(dmatches, uint64_t, i);
+        if (v == vaddr) {
+            ctx->log = true;
+            return true;
+        }
+    }
+    return false;
+}
 /**
  * Add memory read or write information to current instruction log
  */
@@ -57,6 +70,9 @@  static void vcpu_mem(unsigned int cpu_index, qemu_plugin_meminfo_t info,
     struct execlog_ctx *ctx = g_ptr_array_index(last_exec, cpu_index);
     g_rw_lock_reader_unlock(&expand_array_lock);
 
+    if (dmatches && !match_vaddr(ctx, vaddr)) {
+        return;
+    }
     GString *s = ctx->s;
     /* Indicate type of memory access */
     if (qemu_plugin_mem_is_store(info)) {
@@ -93,7 +109,7 @@  static void vcpu_insn_exec(unsigned int cpu_index, void *udata)
     GString *s = ctx->s;
 
     /* Print previous instruction in cache */
-    if (s->len) {
+    if (ctx->log && s->len) {
         qemu_plugin_outs(s->str);
         qemu_plugin_outs("\n");
     }
@@ -102,6 +118,7 @@  static void vcpu_insn_exec(unsigned int cpu_index, void *udata)
     /* vcpu_mem will add memory access information to last_exec */
     g_string_printf(s, "%u, ", cpu_index);
     g_string_append(s, (char *)udata);
+    ctx->log = dmatches ? false : true;
 }
 
 /**
@@ -190,7 +207,7 @@  static void plugin_exit(qemu_plugin_id_t id, void *p)
     for (i = 0; i < last_exec->len; i++) {
         struct execlog_ctx *ctx = g_ptr_array_index(last_exec, i);
         GString *s = ctx->s;
-        if (s->str) {
+        if (ctx->log && s->str) {
             qemu_plugin_outs(s->str);
             qemu_plugin_outs("\n");
         }
@@ -240,6 +257,8 @@  QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
             parse_insn_match(tokens[1]);
         } else if (g_strcmp0(tokens[0], "afilter") == 0) {
             parse_vaddr_match(&amatches, tokens[1]);
+        } else if (g_strcmp0(tokens[0], "dfilter") == 0) {
+            parse_vaddr_match(&dmatches, tokens[1]);
         } else {
             fprintf(stderr, "option parsing failed: %s\n", opt);
             return -1;