Commit a9c0b33e authored by Shradha Gupta's avatar Shradha Gupta Committed by Wei Liu
Browse files

tools: hv: Enable debug logs for hv_kvp_daemon 



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 syslog with loglevel LOG_DEBUG. This information comes
in handy for debugging issues where the key-value pairs for certain
pools show mismatch/incorrect values.
The distro-vendors can further consume these changes and modify the
respective service files to redirect the logs to specific files as
needed.

Signed-off-by: default avatarShradha Gupta <shradhagupta@linux.microsoft.com>
Reviewed-by: default avatarNaman Jain <namjain@linux.microsoft.com>
Reviewed-by: default avatarDexuan Cui <decui@microsoft.com>
Link: https://lore.kernel.org/r/1744715978-8185-1-git-send-email-shradhagupta@linux.microsoft.com


Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
Message-ID: <1744715978-8185-1-git-send-email-shradhagupta@linux.microsoft.com>
parent 82f2b0b9

tools/hv/hv_kvp_daemon.c

+59 −5
Original line number Diff line number Diff line
@@ -84,6 +84,7 @@ enum { 
};



static int in_hand_shake;

static int debug;



static char *os_name = "";

static char *os_major = "";
@@ -184,6 +185,20 @@ static void kvp_update_file(int pool) 
	kvp_release_lock(pool);

}



static void kvp_dump_initial_pools(int pool)

{

	int i;



	syslog(LOG_DEBUG, "===Start dumping the contents of pool %d ===\n",

	       pool);



	for (i = 0; i < kvp_file_info[pool].num_records; i++)

		syslog(LOG_DEBUG, "pool: %d, %d/%d key=%s val=%s\n",

		       pool, i + 1, kvp_file_info[pool].num_records,

		       kvp_file_info[pool].records[i].key,

		       kvp_file_info[pool].records[i].value);

}



static void kvp_update_mem_state(int pool)

{

	FILE *filep;
@@ -271,6 +286,8 @@ static int kvp_file_init(void) 
			return 1;

		kvp_file_info[i].num_records = 0;

		kvp_update_mem_state(i);

		if (debug)

			kvp_dump_initial_pools(i);

	}



	return 0;
@@ -298,6 +315,9 @@ static int kvp_key_delete(int pool, const __u8 *key, int key_size) 
		 * Found a match; just move the remaining

		 * entries up.

		 */

		if (debug)

			syslog(LOG_DEBUG, "%s: deleting the KVP: pool=%d key=%s val=%s",

			       __func__, pool, record[i].key, record[i].value);

		if (i == (num_records - 1)) {

			kvp_file_info[pool].num_records--;

			kvp_update_file(pool);
@@ -316,20 +336,36 @@ static int kvp_key_delete(int pool, const __u8 *key, int key_size) 
		kvp_update_file(pool);

		return 0;

	}



	if (debug)

		syslog(LOG_DEBUG, "%s: could not delete KVP: pool=%d key=%s. Record not found",

		       __func__, pool, key);



	return 1;

}



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;

	int num_records;

	int num_blocks;

	int i;



	if (debug)

		syslog(LOG_DEBUG, "%s: got a KVP: pool=%d key=%s val=%s",

		       __func__, 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, "%s: Too long key or value: key=%s, val=%s",

		       __func__, key, value);



		if (debug)

			syslog(LOG_DEBUG, "%s: Too long key or value: pool=%d, key=%s, val=%s",

			       __func__, pool, key, value);

		return 1;

	}



	/*

	 * First update the in-memory state.
@@ -349,6 +385,9 @@ 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 (debug)

			syslog(LOG_DEBUG, "%s: updated: pool=%d key=%s val=%s",

			       __func__, pool, key, value);

		return 0;

	}
@@ -360,8 +399,10 @@ 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) {

			syslog(LOG_ERR, "%s: Memory alloc failure", __func__);

			return 1;

		}

		kvp_file_info[pool].num_blocks++;



	}
@@ -369,6 +410,11 @@ 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 (debug)

		syslog(LOG_DEBUG, "%s: added: pool=%d key=%s val=%s",

		       __func__, pool, key, value);



	kvp_update_file(pool);

	return 0;

}
@@ -1722,6 +1768,7 @@ 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            Enable debug logs(syslog debug by default)\n"

		"  -h, --help             print this help\n", argv[0]);

}
@@ -1743,10 +1790,11 @@ int main(int argc, char *argv[]) 
	static struct option long_options[] = {

		{"help",	no_argument,	   0,  'h' },

		{"no-daemon",	no_argument,	   0,  'n' },

		{"debug",	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':
@@ -1755,6 +1803,9 @@ int main(int argc, char *argv[]) 
		case 'h':

			print_usage(argv);

			exit(0);

		case 'd':

			debug = 1;

			break;

		default:

			print_usage(argv);

			exit(EXIT_FAILURE);
@@ -1777,6 +1828,9 @@ int main(int argc, char *argv[]) 
	 */

	kvp_get_domain_name(full_domain_name, sizeof(full_domain_name));



	if (debug)

		syslog(LOG_INFO, "Logging debug info in syslog(debug)");



	if (kvp_file_init()) {

		syslog(LOG_ERR, "Failed to initialize the pools");

		exit(EXIT_FAILURE);