Allow the KVP daemon to log the KVP updates triggered in the VM
with a new debug flag(-d).
When the daemon is started with this flag, it logs updates and debug
information in /var/log/kvp_debug_file.log. This information comes
in handy for debugging issues where the key-value pairs for certain
pools show mismatch/incorrect values.
Signed-off-by: Shradha Gupta <shradhagu...@linux.microsoft.com>
---
tools/hv/hv_kvp_daemon.c | 120 ++++++++++++++++++++++++++++++++++++---
1 file changed, 112 insertions(+), 8 deletions(-)
diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index 04ba035d67e9..1f8b02b17356 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -41,6 +41,7 @@
#include <net/if.h>
#include <limits.h>
#include <getopt.h>
+#include <time.h>
/*
* KVP protocol: The user mode component first registers with the
@@ -83,6 +84,7 @@ enum {
};
static int in_hand_shake;
+static int debug_enabled;
static char *os_name = "";
static char *os_major = "";
@@ -91,6 +93,7 @@ static char *processor_arch;
static char *os_build;
static char *os_version;
static char *lic_version = "Unknown version";
+static char debug_file[PATH_MAX];
static char full_domain_name[HV_KVP_EXCHANGE_MAX_VALUE_SIZE];
static struct utsname uts_buf;
@@ -99,6 +102,7 @@ static struct utsname uts_buf;
*/
#define KVP_CONFIG_LOC "/var/lib/hyperv"
+#define KVP_DEBUG_LOC "/var/log/"
#ifndef KVP_SCRIPTS_PATH
#define KVP_SCRIPTS_PATH "/usr/libexec/hypervkvpd/"
@@ -153,6 +157,16 @@ static void kvp_release_lock(int pool)
}
}
+static void convert_tm_to_string(char *tm_str, size_t tm_str_size)
+{
+ struct tm tm;
+ time_t t;
+
+ time(&t);
+ gmtime_r(&t, &tm);
+ strftime(tm_str, tm_str_size, "%Y-%m-%dT%H:%M:%S", &tm);
+}
+
static void kvp_update_file(int pool)
{
FILE *filep;
@@ -183,6 +197,45 @@ static void kvp_update_file(int pool)
kvp_release_lock(pool);
}
+static void kvp_dump_initial_pools(int pool)
+{
+ FILE *debug_filep;
+ char tm_str[50];
+ int i, ret;
+
+ convert_tm_to_string(tm_str, sizeof(tm_str));
+
+ debug_filep = fopen(debug_file, "a");
+ if (!debug_filep) {
+ syslog(LOG_ERR, "Failed to open file: %s, pool: %d; error:
%d%s",
+ debug_file, pool, errno, strerror(errno));
+ return;
+ }
+
+ ret = fprintf(debug_filep, "===Start dumping the contents on pool %d
===\n",
+ pool);
+ if (ret <= 0) {
+ syslog(LOG_ERR, "Failed to write to kvp debug file: %d", pool);
+ fclose(debug_filep);
+ return;
+ }
+
+ for (i = 0; i < kvp_file_info[pool].num_records; i++) {
+ ret = fprintf(debug_filep, "[%s]: pool: %d, %d/%d key=%s
val=%s\n",
+ tm_str, pool, i, kvp_file_info[pool].num_records,
+ kvp_file_info[pool].records[i].key,
+ kvp_file_info[pool].records[i].value);
+
+ if (ret <= 0) {
+ syslog(LOG_ERR, "Failed to write to kvp debug file:
pool=%d, i=%u/%u",
+ pool, i, kvp_file_info[pool].num_records);
+ break;
+ }
+ }
+
+ fclose(debug_filep);
+}
+
static void kvp_update_mem_state(int pool)
{
FILE *filep;
@@ -270,6 +323,8 @@ static int kvp_file_init(void)
return 1;
kvp_file_info[i].num_records = 0;
kvp_update_mem_state(i);
+ if (debug_enabled)
+ kvp_dump_initial_pools(i);
}
return 0;
@@ -321,14 +376,37 @@ static int kvp_key_delete(int pool, const __u8 *key, int
key_size)
static int kvp_key_add_or_modify(int pool, const __u8 *key, int key_size,
const __u8 *value, int value_size)
{
- int i;
- int num_records;
struct kvp_record *record;
+ FILE *filep = NULL;
+ int num_records;
+ char tm_str[50];
int num_blocks;
+ int i;
+
+ if (debug_enabled) {
+ filep = fopen(debug_file, "a");
+ if (!filep) {
+ syslog(LOG_ERR, "Failed to open file %s; error: %d",
+ debug_file, errno);
+ } else {
+ convert_tm_to_string(tm_str, sizeof(tm_str));
+ fprintf(filep, "[%s]:%s: got a KVP: pool=%d key=%s
val=%s\n",
+ __func__, tm_str, pool, key, value);
+ }
+ }
if ((key_size > HV_KVP_EXCHANGE_MAX_KEY_SIZE) ||
- (value_size > HV_KVP_EXCHANGE_MAX_VALUE_SIZE))
+ (value_size > HV_KVP_EXCHANGE_MAX_VALUE_SIZE)) {
+ syslog(LOG_ERR, "Got a too long key or value: key=%s, val=%s",
+ key, value);
+
+ if (filep) {
+ fprintf(filep, "[%s]: Got a too long key or value:
pool=%d, key=%s, val=%s\n",
+ tm_str, pool, key, value);
+ fclose(filep);
+ }
return 1;
+ }
/*
* First update the in-memory state.
@@ -348,6 +426,11 @@ static int kvp_key_add_or_modify(int pool, const __u8
*key, int key_size,
*/
memcpy(record[i].value, value, value_size);
kvp_update_file(pool);
+ if (filep) {
+ fprintf(filep, "[%s]:%s: updated: pool=%d key=%s
val=%s\n",
+ __func__, tm_str, pool, key, value);
+ fclose(filep);
+ }
return 0;
}
@@ -359,8 +442,12 @@ static int kvp_key_add_or_modify(int pool, const __u8
*key, int key_size,
record = realloc(record, sizeof(struct kvp_record) *
ENTRIES_PER_BLOCK * (num_blocks + 1));
- if (record == NULL)
+ if (!record) {
+ if (filep)
+ fclose(filep);
+ syslog(LOG_ERR, "%s: Memory alloc failure", __func__);
return 1;
+ }
kvp_file_info[pool].num_blocks++;
}
@@ -368,6 +455,12 @@ static int kvp_key_add_or_modify(int pool, const __u8
*key, int key_size,
memcpy(record[i].key, key, key_size);
kvp_file_info[pool].records = record;
kvp_file_info[pool].num_records++;
+
+ if (filep) {
+ fprintf(filep, "[%s]:%s: added: pool=%d key=%s val=%s\n",
+ __func__, tm_str, pool, key, value);
+ fclose(filep);
+ }
kvp_update_file(pool);
return 0;
}
@@ -1662,6 +1755,7 @@ void print_usage(char *argv[])
fprintf(stderr, "Usage: %s [options]\n"
"Options are:\n"
" -n, --no-daemon stay in foreground, don't daemonize\n"
+ " -d, --debug-enabled Enable debug logs\n"
" -h, --help print this help\n", argv[0]);
}
@@ -1681,12 +1775,13 @@ int main(int argc, char *argv[])
int daemonize = 1, long_index = 0, opt;
static struct option long_options[] = {
- {"help", no_argument, 0, 'h' },
- {"no-daemon", no_argument, 0, 'n' },
- {0, 0, 0, 0 }
+ {"help", no_argument, 0, 'h' },
+ {"no-daemon", no_argument, 0, 'n' },
+ {"debug-enabled", no_argument, 0, 'd' },
+ {0, 0, 0, 0 }
};
- while ((opt = getopt_long(argc, argv, "hn", long_options,
+ while ((opt = getopt_long(argc, argv, "hnd", long_options,
&long_index)) != -1) {
switch (opt) {
case 'n':
@@ -1695,6 +1790,9 @@ int main(int argc, char *argv[])
case 'h':
print_usage(argv);
exit(0);
+ case 'd':
+ debug_enabled = 1;
+ break;
default:
print_usage(argv);
exit(EXIT_FAILURE);
@@ -1717,6 +1815,12 @@ int main(int argc, char *argv[])
*/
kvp_get_domain_name(full_domain_name, sizeof(full_domain_name));
+ if (debug_enabled) {
+ sprintf(debug_file, "%s%s", KVP_DEBUG_LOC,
"kvp_debug_file.log");
+ syslog(LOG_INFO, "Logging debug info in kvp_debug_file=%s",
+ debug_file);
+ }
+
if (kvp_file_init()) {
syslog(LOG_ERR, "Failed to initialize the pools");
exit(EXIT_FAILURE);
--
2.34.1
