diff options
Diffstat (limited to 'lib/thread.c')
| -rw-r--r-- | lib/thread.c | 134 |
1 files changed, 86 insertions, 48 deletions
diff --git a/lib/thread.c b/lib/thread.c index e89af541..1e714417 100644 --- a/lib/thread.c +++ b/lib/thread.c @@ -20,8 +20,9 @@ */ /* #define DEBUG */ - +#include <errno.h> #include <zebra.h> +#include <sys/times.h> #include "thread.h" #include "memory.h" @@ -31,8 +32,7 @@ #include "sigevent.h" /* Recent absolute time of day */ -struct timeval recent_time; -static struct timeval last_recent_time; +static struct timeval recent_time; /* Relative time, since startup */ static struct timeval relative_time; static struct timeval relative_time_base; @@ -94,54 +94,98 @@ timeval_elapsed (struct timeval a, struct timeval b) } #ifndef HAVE_CLOCK_MONOTONIC +static unsigned long recent_clock_mark; /* Holds value of last call to times(2) */ +static unsigned long last_clock_mark; +static unsigned long clocks_per_sec, msec_scale, usec_scale; + +static unsigned long quagga_times(void) +{ +#if defined(GNU_LINUX) + unsigned long ret; + + errno = 0; + ret = times(NULL); /* Linux can handle NULL */ + /* Workaround broken syscall impl. + * A bugfix exists for the kernel, hopefully + * it will make it into 2.6.28 + */ + if (errno) + ret = (unsigned long) (-errno); + return ret; +#else + struct tms dummy; /* Only return value is used */ + + return times(&dummy); +#endif +} + static void quagga_gettimeofday_relative_adjust (void) { - struct timeval diff; - if (timeval_cmp (recent_time, last_recent_time) < 0) - { - relative_time.tv_sec++; - relative_time.tv_usec = 0; - } - else - { - diff = timeval_subtract (recent_time, last_recent_time); - relative_time.tv_sec += diff.tv_sec; - relative_time.tv_usec += diff.tv_usec; - relative_time = timeval_adjust (relative_time); - } - last_recent_time = recent_time; + unsigned long diff; + + diff = recent_clock_mark - last_clock_mark; + if (!diff) + return; + /* save mark for next calculation */ + last_clock_mark = recent_clock_mark; + + relative_time.tv_sec += diff / clocks_per_sec; /* convert to seconds */ + relative_time.tv_usec += (diff % clocks_per_sec) * usec_scale; /* convert to useconds */ + relative_time = timeval_adjust (relative_time); } #endif /* !HAVE_CLOCK_MONOTONIC */ +static int init_quagga_timers(void) +{ + int ret; + + ret = gettimeofday (&recent_time, NULL); + relative_time_base = recent_time; +#if !defined(HAVE_CLOCK_MONOTONIC) + clocks_per_sec = sysconf(_SC_CLK_TCK); + assert(clocks_per_sec != 0); + + /* Precondition: 1000 % clocks_per_sec == 0 */ + assert(1000 % clocks_per_sec == 0); + msec_scale = 1000 / clocks_per_sec; + + /* Precondition: TIMER_SECOND_MICRO % clocks_per_sec == 0 */ + assert(TIMER_SECOND_MICRO % clocks_per_sec == 0); + usec_scale = TIMER_SECOND_MICRO / clocks_per_sec; + recent_clock_mark = quagga_times(); + last_clock_mark = recent_clock_mark; +#endif + if (ret) + return ret; + timers_inited = 1; + return 0; +} + /* gettimeofday wrapper, to keep recent_time updated */ static int quagga_gettimeofday (struct timeval *tv) { int ret; - - assert (tv); - - if (!(ret = gettimeofday (&recent_time, NULL))) - { - /* init... */ - if (!timers_inited) - { - relative_time_base = last_recent_time = recent_time; - timers_inited = 1; - } - /* avoid copy if user passed recent_time pointer.. */ - if (tv != &recent_time) - *tv = recent_time; - return 0; - } - return ret; + + /* init... */ + if (!timers_inited) + ret = init_quagga_timers(); + else + ret = gettimeofday (&recent_time, NULL); + if (ret) + return ret; + + /* avoid copy if user passed recent_time pointer.. */ + if (tv != &recent_time) + *tv = recent_time; + return 0; } static int quagga_get_relative (struct timeval *tv) { - int ret; + int ret = 0; #ifdef HAVE_CLOCK_MONOTONIC { @@ -153,8 +197,12 @@ quagga_get_relative (struct timeval *tv) } } #else /* !HAVE_CLOCK_MONOTONIC */ - if (!(ret = quagga_gettimeofday (&recent_time))) - quagga_gettimeofday_relative_adjust(); + /* init... */ + if (!timers_inited) + ret = init_quagga_timers(); + + recent_clock_mark = quagga_times(); + quagga_gettimeofday_relative_adjust(); #endif /* HAVE_CLOCK_MONOTONIC */ if (tv) @@ -910,7 +958,6 @@ thread_fetch (struct thread_master *m, struct thread *fetch) struct thread *thread; fd_set readfd; fd_set writefd; - fd_set exceptfd; struct timeval timer_val; struct timeval timer_val_bg; struct timeval *timer_wait; @@ -936,7 +983,6 @@ thread_fetch (struct thread_master *m, struct thread *fetch) /* Structure copy. */ readfd = m->readfd; writefd = m->writefd; - exceptfd = m->exceptfd; /* Calculate select wait timer if nothing else to do */ quagga_get_relative (NULL); @@ -947,7 +993,7 @@ thread_fetch (struct thread_master *m, struct thread *fetch) (!timer_wait || (timeval_cmp (*timer_wait, *timer_wait_bg) > 0))) timer_wait = timer_wait_bg; - num = select (FD_SETSIZE, &readfd, &writefd, &exceptfd, timer_wait); + num = select (FD_SETSIZE, &readfd, &writefd, NULL, timer_wait); /* Signals should get quick treatment */ if (num < 0) @@ -1028,14 +1074,6 @@ thread_getrusage (RUSAGE_T *r) getrusage(RUSAGE_SELF, &(r->cpu)); #endif r->real = relative_time; - -#ifdef HAVE_CLOCK_MONOTONIC - /* quagga_get_relative() only updates recent_time if gettimeofday - * based, not when using CLOCK_MONOTONIC. As we export recent_time - * and guarantee to update it before threads are run... - */ - quagga_gettimeofday(&recent_time); -#endif /* HAVE_CLOCK_MONOTONIC */ } /* We check thread consumed time. If the system has getrusage, we'll |