X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Fprintk.c;h=f38b07f78a4e864da8fb2c7bcc5a0641bd04e7b5;hb=1d510750941a53a1d3049c1d33c75d6dfcd78618;hp=55d16e57499a90e87cfbd756a4204e2817bcc082;hpb=42fdfa238a23643226910acf922ea930b3286032;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/printk.c b/kernel/printk.c index 55d16e5..f38b07f 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -13,7 +13,7 @@ * Fixed SMP synchronization, 08/08/99, Manfred Spraul * manfred@colorfullife.com * Rewrote bits to get rid of console_lock - * 01Mar01 Andrew Morton + * 01Mar01 Andrew Morton */ #include @@ -32,13 +32,20 @@ #include #include #include +#include #include /* + * for_each_console() allows you to iterate on each console + */ +#define for_each_console(con) \ + for (con = console_drivers; con != NULL; con = con->next) + +/* * Architectures can override it: */ -void __attribute__((weak)) early_printk(const char *fmt, ...) +void asmlinkage __attribute__((weak)) early_printk(const char *fmt, ...) { } @@ -60,6 +67,8 @@ int console_printk[4] = { DEFAULT_CONSOLE_LOGLEVEL, /* default_console_loglevel */ }; +static int saved_console_loglevel = -1; + /* * Low level drivers may need that to know if they can schedule in * their unblank() callback or not. So let's export it. @@ -73,8 +82,9 @@ EXPORT_SYMBOL(oops_in_progress); * driver system. */ static DECLARE_MUTEX(console_sem); -static DECLARE_MUTEX(secondary_console_sem); struct console *console_drivers; +EXPORT_SYMBOL_GPL(console_drivers); + /* * This is used for debugging the mess that is the VT code by * keeping track if we have the console semaphore held. It's @@ -121,6 +131,8 @@ struct console_cmdline static struct console_cmdline console_cmdline[MAX_CMDLINECONSOLES]; static int selected_console = -1; static int preferred_console = -1; +int console_set_on_cmdline; +EXPORT_SYMBOL(console_set_on_cmdline); /* Flag: console code may call schedule() */ static int console_may_schedule; @@ -132,6 +144,24 @@ static char *log_buf = __log_buf; static int log_buf_len = __LOG_BUF_LEN; static unsigned logged_chars; /* Number of chars produced since last read+clear operation */ +#ifdef CONFIG_KEXEC +/* + * This appends the listed symbols to /proc/vmcoreinfo + * + * /proc/vmcoreinfo is used by various utiilties, like crash and makedumpfile to + * obtain access to symbols that are otherwise very difficult to locate. These + * symbols are specifically used so that utilities can access and extract the + * dmesg log from a vmcore file after a crash. + */ +void log_buf_kexec_setup(void) +{ + VMCOREINFO_SYMBOL(log_buf); + VMCOREINFO_SYMBOL(log_end); + VMCOREINFO_SYMBOL(log_buf_len); + VMCOREINFO_SYMBOL(logged_chars); +} +#endif + static int __init log_buf_len_setup(char *str) { unsigned size = memparse(str, &str); @@ -176,12 +206,11 @@ __setup("log_buf_len=", log_buf_len_setup); #ifdef CONFIG_BOOT_PRINTK_DELAY static unsigned int boot_delay; /* msecs delay after each printk during bootup */ -static unsigned long long printk_delay_msec; /* per msec, based on boot_delay */ +static unsigned long long loops_per_msec; /* based on boot_delay */ static int __init boot_delay_setup(char *str) { unsigned long lpj; - unsigned long long loops_per_msec; lpj = preset_lpj ? preset_lpj : 1000000; /* some guess */ loops_per_msec = (unsigned long long)lpj / 1000 * HZ; @@ -190,10 +219,9 @@ static int __init boot_delay_setup(char *str) if (boot_delay > 10 * 1000) boot_delay = 0; - printk_delay_msec = loops_per_msec; - printk(KERN_DEBUG "boot_delay: %u, preset_lpj: %ld, lpj: %lu, " - "HZ: %d, printk_delay_msec: %llu\n", - boot_delay, preset_lpj, lpj, HZ, printk_delay_msec); + pr_debug("boot_delay: %u, preset_lpj: %ld, lpj: %lu, " + "HZ: %d, loops_per_msec: %llu\n", + boot_delay, preset_lpj, lpj, HZ, loops_per_msec); return 1; } __setup("boot_delay=", boot_delay_setup); @@ -206,7 +234,7 @@ static void boot_delay_msec(void) if (boot_delay == 0 || system_state != SYSTEM_BOOTING) return; - k = (unsigned long long)printk_delay_msec * boot_delay; + k = (unsigned long long)loops_per_msec * boot_delay; timeout = jiffies + msecs_to_jiffies(boot_delay); while (k) { @@ -229,45 +257,6 @@ static inline void boot_delay_msec(void) #endif /* - * Return the number of unread characters in the log buffer. - */ -static int log_buf_get_len(void) -{ - return logged_chars; -} - -/* - * Copy a range of characters from the log buffer. - */ -int log_buf_copy(char *dest, int idx, int len) -{ - int ret, max; - bool took_lock = false; - - if (!oops_in_progress) { - spin_lock_irq(&logbuf_lock); - took_lock = true; - } - - max = log_buf_get_len(); - if (idx < 0 || idx >= max) { - ret = -1; - } else { - if (len > max) - len = max; - ret = len; - idx += (log_end - max); - while (len-- > 0) - dest[len] = LOG_BUF(idx + len); - } - - if (took_lock) - spin_unlock_irq(&logbuf_lock); - - return ret; -} - -/* * Commands to do_syslog: * * 0 -- Close the log. Currently a NOP. @@ -389,10 +378,15 @@ int do_syslog(int type, char __user *buf, int len) logged_chars = 0; break; case 6: /* Disable logging to console */ + if (saved_console_loglevel == -1) + saved_console_loglevel = console_loglevel; console_loglevel = minimum_console_loglevel; break; case 7: /* Enable logging to console */ - console_loglevel = default_console_loglevel; + if (saved_console_loglevel != -1) { + console_loglevel = saved_console_loglevel; + saved_console_loglevel = -1; + } break; case 8: /* Set level of messages printed to console */ error = -EINVAL; @@ -401,6 +395,8 @@ int do_syslog(int type, char __user *buf, int len) if (len < minimum_console_loglevel) len = minimum_console_loglevel; console_loglevel = len; + /* Implicitly re-enable logging to console */ + saved_console_loglevel = -1; error = 0; break; case 9: /* Number of chars in the log buffer */ @@ -417,7 +413,7 @@ out: return error; } -asmlinkage long sys_syslog(int type, char __user *buf, int len) +SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len) { return do_syslog(type, buf, len); } @@ -429,7 +425,7 @@ static void __call_console_drivers(unsigned start, unsigned end) { struct console *con; - for (con = console_drivers; con; con = con->next) { + for_each_console(con) { if ((con->flags & CON_ENABLED) && con->write && (cpu_online(smp_processor_id()) || (con->flags & CON_ANYTIME))) @@ -561,7 +557,7 @@ static int have_callable_console(void) { struct console *con; - for (con = console_drivers; con; con = con->next) + for_each_console(con) if (con->flags & CON_ANYTIME) return 1; @@ -573,9 +569,6 @@ static int have_callable_console(void) * @fmt: format string * * This is printk(). It can be called from any context. We want it to work. - * Be aware of the fact that if oops_in_progress is not set, we might try to - * wake klogd up which could deadlock on runqueue lock if printk() is called - * from scheduler code. * * We try to grab the console_sem. If we succeed, it's easy - we log the output and * call the console drivers. If we fail to get the semaphore we place the output @@ -589,6 +582,8 @@ static int have_callable_console(void) * * See also: * printf(3) + * + * See the vsnprintf() documentation for format string extensions over C99. */ asmlinkage int printk(const char *fmt, ...) @@ -652,22 +647,36 @@ static int acquire_console_semaphore_for_printk(unsigned int cpu) spin_unlock(&logbuf_lock); return retval; } +static const char recursion_bug_msg [] = + KERN_CRIT "BUG: recent printk recursion!\n"; +static int recursion_bug; +static int new_text_line = 1; +static char printk_buf[1024]; -const char printk_recursion_bug_msg [] = - KERN_CRIT "BUG: recent printk recursion!\n"; -static int printk_recursion_bug; +int printk_delay_msec __read_mostly; -asmlinkage int vprintk(const char *fmt, va_list args) +static inline void printk_delay(void) { - static int log_level_unknown = 1; - static char printk_buf[1024]; + if (unlikely(printk_delay_msec)) { + int m = printk_delay_msec; - unsigned long flags; + while (m--) { + mdelay(1); + touch_nmi_watchdog(); + } + } +} + +asmlinkage int vprintk(const char *fmt, va_list args) +{ int printed_len = 0; + int current_log_level = default_message_loglevel; + unsigned long flags; int this_cpu; char *p; boot_delay_msec(); + printk_delay(); preempt_disable(); /* This stops the holder of console_sem just where we want him */ @@ -686,7 +695,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) * it can be printed at the next appropriate moment: */ if (!oops_in_progress) { - printk_recursion_bug = 1; + recursion_bug = 1; goto out_restore_irqs; } zap_locks(); @@ -696,70 +705,77 @@ asmlinkage int vprintk(const char *fmt, va_list args) spin_lock(&logbuf_lock); printk_cpu = this_cpu; - if (printk_recursion_bug) { - printk_recursion_bug = 0; - strcpy(printk_buf, printk_recursion_bug_msg); - printed_len = sizeof(printk_recursion_bug_msg); + if (recursion_bug) { + recursion_bug = 0; + strcpy(printk_buf, recursion_bug_msg); + printed_len = strlen(recursion_bug_msg); } /* Emit the output into the temporary buffer */ printed_len += vscnprintf(printk_buf + printed_len, sizeof(printk_buf) - printed_len, fmt, args); + + p = printk_buf; + + /* Do we have a loglevel in the string? */ + if (p[0] == '<') { + unsigned char c = p[1]; + if (c && p[2] == '>') { + switch (c) { + case '0' ... '7': /* loglevel */ + current_log_level = c - '0'; + /* Fallthrough - make sure we're on a new line */ + case 'd': /* KERN_DEFAULT */ + if (!new_text_line) { + emit_log_char('\n'); + new_text_line = 1; + } + /* Fallthrough - skip the loglevel */ + case 'c': /* KERN_CONT */ + p += 3; + break; + } + } + } + /* * Copy the output into log_buf. If the caller didn't provide * appropriate log level tags, we insert them here */ - for (p = printk_buf; *p; p++) { - if (log_level_unknown) { - /* log_level_unknown signals the start of a new line */ + for ( ; *p; p++) { + if (new_text_line) { + /* Always output the token */ + emit_log_char('<'); + emit_log_char(current_log_level + '0'); + emit_log_char('>'); + printed_len += 3; + new_text_line = 0; + if (printk_time) { - int loglev_char; + /* Follow the token with the time */ char tbuf[50], *tp; unsigned tlen; unsigned long long t; unsigned long nanosec_rem; - /* - * force the log level token to be - * before the time output. - */ - if (p[0] == '<' && p[1] >='0' && - p[1] <= '7' && p[2] == '>') { - loglev_char = p[1]; - p += 3; - printed_len -= 3; - } else { - loglev_char = default_message_loglevel - + '0'; - } t = cpu_clock(printk_cpu); nanosec_rem = do_div(t, 1000000000); - tlen = sprintf(tbuf, - "<%c>[%5lu.%06lu] ", - loglev_char, - (unsigned long)t, - nanosec_rem/1000); + tlen = sprintf(tbuf, "[%5lu.%06lu] ", + (unsigned long) t, + nanosec_rem / 1000); for (tp = tbuf; tp < tbuf + tlen; tp++) emit_log_char(*tp); printed_len += tlen; - } else { - if (p[0] != '<' || p[1] < '0' || - p[1] > '7' || p[2] != '>') { - emit_log_char('<'); - emit_log_char(default_message_loglevel - + '0'); - emit_log_char('>'); - printed_len += 3; - } } - log_level_unknown = 0; + if (!*p) break; } + emit_log_char(*p); if (*p == '\n') - log_level_unknown = 1; + new_text_line = 1; } /* @@ -787,11 +803,6 @@ EXPORT_SYMBOL(vprintk); #else -asmlinkage long sys_syslog(int type, char __user *buf, int len) -{ - return -ENOSYS; -} - static void call_console_drivers(unsigned start, unsigned end) { } @@ -877,6 +888,7 @@ static int __init console_setup(char *str) *s = 0; __add_preferred_console(buf, idx, options, brl_options); + console_set_on_cmdline = 1; return 1; } __setup("console=", console_setup); @@ -937,15 +949,17 @@ void suspend_console(void) { if (!console_suspend_enabled) return; - printk("Suspending console(s)\n"); + printk("Suspending console(s) (use no_console_suspend to debug)\n"); acquire_console_sem(); console_suspended = 1; + up(&console_sem); } void resume_console(void) { if (!console_suspend_enabled) return; + down(&console_sem); console_suspended = 0; release_console_sem(); } @@ -961,11 +975,9 @@ void resume_console(void) void acquire_console_sem(void) { BUG_ON(in_interrupt()); - if (console_suspended) { - down(&secondary_console_sem); - return; - } down(&console_sem); + if (console_suspended) + return; console_locked = 1; console_may_schedule = 1; } @@ -975,6 +987,10 @@ int try_acquire_console_sem(void) { if (down_trylock(&console_sem)) return -1; + if (console_suspended) { + up(&console_sem); + return -1; + } console_locked = 1; console_may_schedule = 0; return 0; @@ -986,10 +1002,25 @@ int is_console_locked(void) return console_locked; } -void wake_up_klogd(void) +static DEFINE_PER_CPU(int, printk_pending); + +void printk_tick(void) { - if (!oops_in_progress && waitqueue_active(&log_wait)) + if (__get_cpu_var(printk_pending)) { + __get_cpu_var(printk_pending) = 0; wake_up_interruptible(&log_wait); + } +} + +int printk_needs_cpu(int cpu) +{ + return per_cpu(printk_pending, cpu); +} + +void wake_up_klogd(void) +{ + if (waitqueue_active(&log_wait)) + __raw_get_cpu_var(printk_pending) = 1; } /** @@ -1013,7 +1044,7 @@ void release_console_sem(void) unsigned wake_klogd = 0; if (console_suspended) { - up(&secondary_console_sem); + up(&console_sem); return; } @@ -1028,7 +1059,9 @@ void release_console_sem(void) _log_end = log_end; con_start = log_end; /* Flush */ spin_unlock(&logbuf_lock); + stop_critical_timings(); /* don't trace print latency */ call_console_drivers(_con_start, _log_end); + start_critical_timings(); local_irq_restore(flags); } console_locked = 0; @@ -1055,12 +1088,6 @@ void __sched console_conditional_schedule(void) } EXPORT_SYMBOL(console_conditional_schedule); -void console_print(const char *s) -{ - printk(KERN_EMERG "%s", s); -} -EXPORT_SYMBOL(console_print); - void console_unblank(void) { struct console *c; @@ -1077,7 +1104,7 @@ void console_unblank(void) console_locked = 1; console_may_schedule = 0; - for (c = console_drivers; c != NULL; c = c->next) + for_each_console(c) if ((c->flags & CON_ENABLED) && c->unblank) c->unblank(); release_console_sem(); @@ -1092,7 +1119,7 @@ struct tty_driver *console_device(int *index) struct tty_driver *driver = NULL; acquire_console_sem(); - for (c = console_drivers; c != NULL; c = c->next) { + for_each_console(c) { if (!c->device) continue; driver = c->device(c, index); @@ -1129,25 +1156,49 @@ EXPORT_SYMBOL(console_start); * to register the console printing procedure with printk() and to * print any messages that were printed by the kernel before the * console driver was initialized. + * + * This can happen pretty early during the boot process (because of + * early_printk) - sometimes before setup_arch() completes - be careful + * of what kernel features are used - they may not be initialised yet. + * + * There are two types of consoles - bootconsoles (early_printk) and + * "real" consoles (everything which is not a bootconsole) which are + * handled differently. + * - Any number of bootconsoles can be registered at any time. + * - As soon as a "real" console is registered, all bootconsoles + * will be unregistered automatically. + * - Once a "real" console is registered, any attempt to register a + * bootconsoles will be rejected */ -void register_console(struct console *console) +void register_console(struct console *newcon) { int i; unsigned long flags; - struct console *bootconsole = NULL; + struct console *bcon = NULL; - if (console_drivers) { - if (console->flags & CON_BOOT) - return; - if (console_drivers->flags & CON_BOOT) - bootconsole = console_drivers; + /* + * before we register a new CON_BOOT console, make sure we don't + * already have a valid console + */ + if (console_drivers && newcon->flags & CON_BOOT) { + /* find the last or real console */ + for_each_console(bcon) { + if (!(bcon->flags & CON_BOOT)) { + printk(KERN_INFO "Too late to register bootconsole %s%d\n", + newcon->name, newcon->index); + return; + } + } } - if (preferred_console < 0 || bootconsole || !console_drivers) + if (console_drivers && console_drivers->flags & CON_BOOT) + bcon = console_drivers; + + if (preferred_console < 0 || bcon || !console_drivers) preferred_console = selected_console; - if (console->early_setup) - console->early_setup(); + if (newcon->early_setup) + newcon->early_setup(); /* * See if we want to use this console driver. If we @@ -1155,12 +1206,15 @@ void register_console(struct console *console) * that registers here. */ if (preferred_console < 0) { - if (console->index < 0) - console->index = 0; - if (console->setup == NULL || - console->setup(console, NULL) == 0) { - console->flags |= CON_ENABLED | CON_CONSDEV; - preferred_console = 0; + if (newcon->index < 0) + newcon->index = 0; + if (newcon->setup == NULL || + newcon->setup(newcon, NULL) == 0) { + newcon->flags |= CON_ENABLED; + if (newcon->device) { + newcon->flags |= CON_CONSDEV; + preferred_console = 0; + } } } @@ -1170,64 +1224,62 @@ void register_console(struct console *console) */ for (i = 0; i < MAX_CMDLINECONSOLES && console_cmdline[i].name[0]; i++) { - if (strcmp(console_cmdline[i].name, console->name) != 0) + if (strcmp(console_cmdline[i].name, newcon->name) != 0) continue; - if (console->index >= 0 && - console->index != console_cmdline[i].index) + if (newcon->index >= 0 && + newcon->index != console_cmdline[i].index) continue; - if (console->index < 0) - console->index = console_cmdline[i].index; + if (newcon->index < 0) + newcon->index = console_cmdline[i].index; #ifdef CONFIG_A11Y_BRAILLE_CONSOLE if (console_cmdline[i].brl_options) { - console->flags |= CON_BRL; - braille_register_console(console, + newcon->flags |= CON_BRL; + braille_register_console(newcon, console_cmdline[i].index, console_cmdline[i].options, console_cmdline[i].brl_options); return; } #endif - if (console->setup && - console->setup(console, console_cmdline[i].options) != 0) + if (newcon->setup && + newcon->setup(newcon, console_cmdline[i].options) != 0) break; - console->flags |= CON_ENABLED; - console->index = console_cmdline[i].index; + newcon->flags |= CON_ENABLED; + newcon->index = console_cmdline[i].index; if (i == selected_console) { - console->flags |= CON_CONSDEV; + newcon->flags |= CON_CONSDEV; preferred_console = selected_console; } break; } - if (!(console->flags & CON_ENABLED)) + if (!(newcon->flags & CON_ENABLED)) return; - if (bootconsole && (console->flags & CON_CONSDEV)) { - printk(KERN_INFO "console handover: boot [%s%d] -> real [%s%d]\n", - bootconsole->name, bootconsole->index, - console->name, console->index); - unregister_console(bootconsole); - console->flags &= ~CON_PRINTBUFFER; - } else { - printk(KERN_INFO "console [%s%d] enabled\n", - console->name, console->index); - } + /* + * If we have a bootconsole, and are switching to a real console, + * don't print everything out again, since when the boot console, and + * the real console are the same physical device, it's annoying to + * see the beginning boot messages twice + */ + if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) + newcon->flags &= ~CON_PRINTBUFFER; /* * Put this console in the list - keep the * preferred driver at the head of the list. */ acquire_console_sem(); - if ((console->flags & CON_CONSDEV) || console_drivers == NULL) { - console->next = console_drivers; - console_drivers = console; - if (console->next) - console->next->flags &= ~CON_CONSDEV; + if ((newcon->flags & CON_CONSDEV) || console_drivers == NULL) { + newcon->next = console_drivers; + console_drivers = newcon; + if (newcon->next) + newcon->next->flags &= ~CON_CONSDEV; } else { - console->next = console_drivers->next; - console_drivers->next = console; + newcon->next = console_drivers->next; + console_drivers->next = newcon; } - if (console->flags & CON_PRINTBUFFER) { + if (newcon->flags & CON_PRINTBUFFER) { /* * release_console_sem() will print out the buffered messages * for us. @@ -1237,6 +1289,28 @@ void register_console(struct console *console) spin_unlock_irqrestore(&logbuf_lock, flags); } release_console_sem(); + + /* + * By unregistering the bootconsoles after we enable the real console + * we get the "console xxx enabled" message on all the consoles - + * boot consoles, real consoles, etc - this is to ensure that end + * users know there might be something in the kernel's log buffer that + * went to the bootconsole (that they do not see on the real console) + */ + if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) { + /* we need to iterate through twice, to make sure we print + * everything out, before we unregister the console(s) + */ + printk(KERN_INFO "console [%s%d] enabled, bootconsole disabled\n", + newcon->name, newcon->index); + for_each_console(bcon) + if (bcon->flags & CON_BOOT) + unregister_console(bcon); + } else { + printk(KERN_INFO "%sconsole [%s%d] enabled\n", + (newcon->flags & CON_BOOT) ? "boot" : "" , + newcon->name, newcon->index); + } } EXPORT_SYMBOL(register_console); @@ -1279,57 +1353,32 @@ EXPORT_SYMBOL(unregister_console); static int __init disable_boot_consoles(void) { - if (console_drivers != NULL) { - if (console_drivers->flags & CON_BOOT) { + struct console *con; + + for_each_console(con) { + if (con->flags & CON_BOOT) { printk(KERN_INFO "turn off boot console %s%d\n", - console_drivers->name, console_drivers->index); - return unregister_console(console_drivers); + con->name, con->index); + unregister_console(con); } } return 0; } late_initcall(disable_boot_consoles); -/** - * tty_write_message - write a message to a certain tty, not just the console. - * @tty: the destination tty_struct - * @msg: the message to write - * - * This is used for messages that need to be redirected to a specific tty. - * We don't put it into the syslog queue right now maybe in the future if - * really needed. - */ -void tty_write_message(struct tty_struct *tty, char *msg) -{ - if (tty && tty->ops->write) - tty->ops->write(tty, msg, strlen(msg)); - return; -} - #if defined CONFIG_PRINTK + /* * printk rate limiting, lifted from the networking subsystem. * - * This enforces a rate limit: not more than one kernel message - * every printk_ratelimit_jiffies to make a denial-of-service - * attack impossible. + * This enforces a rate limit: not more than 10 kernel messages + * every 5s to make a denial-of-service attack impossible. */ -int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst) -{ - return __ratelimit(ratelimit_jiffies, ratelimit_burst); -} -EXPORT_SYMBOL(__printk_ratelimit); - -/* minimum time in jiffies between messages */ -int printk_ratelimit_jiffies = 5 * HZ; - -/* number of messages we send before ratelimiting */ -int printk_ratelimit_burst = 10; +DEFINE_RATELIMIT_STATE(printk_ratelimit_state, 5 * HZ, 10); int printk_ratelimit(void) { - return __printk_ratelimit(printk_ratelimit_jiffies, - printk_ratelimit_burst); + return __ratelimit(&printk_ratelimit_state); } EXPORT_SYMBOL(printk_ratelimit); @@ -1345,8 +1394,11 @@ EXPORT_SYMBOL(printk_ratelimit); bool printk_timed_ratelimit(unsigned long *caller_jiffies, unsigned int interval_msecs) { - if (*caller_jiffies == 0 || time_after(jiffies, *caller_jiffies)) { - *caller_jiffies = jiffies + msecs_to_jiffies(interval_msecs); + if (*caller_jiffies == 0 + || !time_in_range(jiffies, *caller_jiffies, + *caller_jiffies + + msecs_to_jiffies(interval_msecs))) { + *caller_jiffies = jiffies; return true; } return false;