Commit 9a5db530 authored by Sumit Garg's avatar Sumit Garg Committed by Daniel Thompson
Browse files

kdb: Simplify kdb_defcmd macro logic 



Switch to use a linked list instead of dynamic array which makes
allocation of kdb macro and traversing the kdb macro commands list
simpler.

Suggested-by: default avatarDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: default avatarSumit Garg <sumit.garg@linaro.org>
Reviewed-by: default avatarDouglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210712134620.276667-4-sumit.garg@linaro.org


Signed-off-by: default avatarDaniel Thompson <daniel.thompson@linaro.org>
parent c25abcd6

kernel/debug/kdb/kdb_main.c

+58 −49
Original line number Diff line number Diff line
@@ -654,13 +654,16 @@ static void kdb_cmderror(int diag) 
 *	zero for success, a kdb diagnostic if error

 */

struct kdb_macro {

	int count;

	bool usable;

	kdbtab_t cmd;

	char **command;

	kdbtab_t cmd;			/* Macro command */

	struct list_head statements;	/* Associated statement list */

};



struct kdb_macro_statement {

	char *statement;		/* Statement text */

	struct list_head list_node;	/* Statement list node */

};



static struct kdb_macro *kdb_macro;

static int kdb_macro_count;

static bool defcmd_in_progress;



/* Forward references */
@@ -668,34 +671,33 @@ static int kdb_exec_defcmd(int argc, const char **argv); 


static int kdb_defcmd2(const char *cmdstr, const char *argv0)

{

	struct kdb_macro *s = kdb_macro + kdb_macro_count - 1;

	char **save_command = s->command;

	struct kdb_macro_statement *kms;



	if (!kdb_macro)

		return KDB_NOTIMP;



	if (strcmp(argv0, "endefcmd") == 0) {

		defcmd_in_progress = false;

		if (!s->count)

			s->usable = false;

		if (s->usable)

			kdb_register(&s->cmd);

		if (!list_empty(&kdb_macro->statements))

			kdb_register(&kdb_macro->cmd);

		return 0;

	}

	if (!s->usable)

		return KDB_NOTIMP;

	s->command = kcalloc(s->count + 1, sizeof(*(s->command)), GFP_KDB);

	if (!s->command) {

		kdb_printf("Could not allocate new kdb_defcmd table for %s\n",



	kms = kmalloc(sizeof(*kms), GFP_KDB);

	if (!kms) {

		kdb_printf("Could not allocate new kdb macro command: %s\n",

			   cmdstr);

		s->usable = false;

		return KDB_NOTIMP;

	}

	memcpy(s->command, save_command, s->count * sizeof(*(s->command)));

	s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);

	kfree(save_command);



	kms->statement = kdb_strdup(cmdstr, GFP_KDB);

	list_add_tail(&kms->list_node, &kdb_macro->statements);



	return 0;

}



static int kdb_defcmd(int argc, const char **argv)

{

	struct kdb_macro *save_kdb_macro = kdb_macro, *s;

	kdbtab_t *mp;



	if (defcmd_in_progress) {
@@ -704,14 +706,22 @@ static int kdb_defcmd(int argc, const char **argv) 
		kdb_defcmd2("endefcmd", "endefcmd");

	}

	if (argc == 0) {

		int i;

		for (s = kdb_macro; s < kdb_macro + kdb_macro_count; ++s) {

			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->cmd.cmd_name,

				   s->cmd.cmd_usage, s->cmd.cmd_help);

			for (i = 0; i < s->count; ++i)

				kdb_printf("%s", s->command[i]);

		kdbtab_t *kp;

		struct kdb_macro *kmp;

		struct kdb_macro_statement *kms;



		list_for_each_entry(kp, &kdb_cmds_head, list_node) {

			if (kp->cmd_func == kdb_exec_defcmd) {

				kdb_printf("defcmd %s \"%s\" \"%s\"\n",

					   kp->cmd_name, kp->cmd_usage,

					   kp->cmd_help);

				kmp = container_of(kp, struct kdb_macro, cmd);

				list_for_each_entry(kms, &kmp->statements,

						    list_node)

					kdb_printf("%s", kms->statement);

				kdb_printf("endefcmd\n");

			}

		}

		return 0;

	}

	if (argc != 3)
@@ -720,17 +730,11 @@ static int kdb_defcmd(int argc, const char **argv) 
		kdb_printf("Command only available during kdb_init()\n");

		return KDB_NOTIMP;

	}

	kdb_macro = kmalloc_array(kdb_macro_count + 1, sizeof(*kdb_macro),

				  GFP_KDB);

	kdb_macro = kzalloc(sizeof(*kdb_macro), GFP_KDB);

	if (!kdb_macro)

		goto fail_defcmd;

	memcpy(kdb_macro, save_kdb_macro,

	       kdb_macro_count * sizeof(*kdb_macro));

	s = kdb_macro + kdb_macro_count;

	memset(s, 0, sizeof(*s));

	s->usable = true;



	mp = &s->cmd;

	mp = &kdb_macro->cmd;

	mp->cmd_func = kdb_exec_defcmd;

	mp->cmd_minlen = 0;

	mp->cmd_flags = KDB_ENABLE_ALWAYS_SAFE;
@@ -751,9 +755,9 @@ static int kdb_defcmd(int argc, const char **argv) 
		strcpy(mp->cmd_help, argv[3]+1);

		mp->cmd_help[strlen(mp->cmd_help)-1] = '\0';

	}

	++kdb_macro_count;



	INIT_LIST_HEAD(&kdb_macro->statements);

	defcmd_in_progress = true;

	kfree(save_kdb_macro);

	return 0;

fail_help:

	kfree(mp->cmd_usage);
@@ -763,7 +767,6 @@ static int kdb_defcmd(int argc, const char **argv) 
	kfree(kdb_macro);

fail_defcmd:

	kdb_printf("Could not allocate new kdb_macro entry for %s\n", argv[1]);

	kdb_macro = save_kdb_macro;

	return KDB_NOTIMP;

}
@@ -778,25 +781,31 @@ static int kdb_defcmd(int argc, const char **argv) 
 */

static int kdb_exec_defcmd(int argc, const char **argv)

{

	int i, ret;

	struct kdb_macro *s;

	int ret;

	kdbtab_t *kp;

	struct kdb_macro *kmp;

	struct kdb_macro_statement *kms;



	if (argc != 0)

		return KDB_ARGCOUNT;

	for (s = kdb_macro, i = 0; i < kdb_macro_count; ++i, ++s) {

		if (strcmp(s->cmd.cmd_name, argv[0]) == 0)



	list_for_each_entry(kp, &kdb_cmds_head, list_node) {

		if (strcmp(kp->cmd_name, argv[0]) == 0)

			break;

	}

	if (i == kdb_macro_count) {

	if (list_entry_is_head(kp, &kdb_cmds_head, list_node)) {

		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",

			   argv[0]);

		return KDB_NOTIMP;

	}

	for (i = 0; i < s->count; ++i) {

		/* Recursive use of kdb_parse, do not use argv after

		 * this point */

	kmp = container_of(kp, struct kdb_macro, cmd);

	list_for_each_entry(kms, &kmp->statements, list_node) {

		/*

		 * Recursive use of kdb_parse, do not use argv after this point.

		 */

		argv = NULL;

		kdb_printf("[%s]kdb> %s\n", s->cmd.cmd_name, s->command[i]);

		ret = kdb_parse(s->command[i]);

		kdb_printf("[%s]kdb> %s\n", kmp->cmd.cmd_name, kms->statement);

		ret = kdb_parse(kms->statement);

		if (ret)

			return ret;

	}