From 9a5db530aa7d98b10c4f5104027565c98cca49e6 Mon Sep 17 00:00:00 2001 From: Sumit Garg Date: Mon, 12 Jul 2021 19:16:19 +0530 Subject: [PATCH] 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: Daniel Thompson Signed-off-by: Sumit Garg Reviewed-by: Douglas Anderson Link: https://lore.kernel.org/r/20210712134620.276667-4-sumit.garg@linaro.org Signed-off-by: Daniel Thompson --- kernel/debug/kdb/kdb_main.c | 107 ++++++++++++++++++++++++-------------------- 1 file changed, 58 insertions(+), 49 deletions(-) diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index b2880fa..7c7a2ef 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -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) { @@ -704,13 +706,21 @@ 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]); - kdb_printf("endefcmd\n"); + 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; } @@ -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 @@ fail_name: 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 @@ fail_defcmd: */ 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; } -- 2.7.4