> -----Original Message-----
> From: Richardson, Bruce
> Sent: Thursday, January 22, 2015 8:19 PM
> To: Liang, Cunming
> Cc: dev at dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v1 02/15] eal: new eal option '--lcores' for
> cpu
> assignment
>
> On Thu, Jan 22, 2015 at 04:16:25PM +0800, Cunming Liang wrote:
> > It supports one new eal long option '--lcores' for EAL thread cpuset
> > assignment.
> >
> > The format pattern:
> > --lcores='lcores[@cpus]<,lcores[@cpus]>'
> > lcores, cpus could be a single digit or a group.
> > '(' and ')' are necessary if it's a group.
> > If not supply '@cpus', the value of cpus uses the same as lcores.
> >
> > e.g. '1,2@(5-7),(3-5)@(0,2),(0,6)' means starting 7 EAL thread as below
> > lcore 0 runs on cpuset 0x41 (cpu 0,6)
> > lcore 1 runs on cpuset 0x2 (cpu 1)
> > lcore 2 runs on cpuset 0xe0 (cpu 5,6,7)
> > lcore 3,4,5 runs on cpuset 0x5 (cpu 0,2)
> > lcore 6 runs on cpuset 0x41 (cpu 0,6)
> >
>
> This strikes me as very confusing, though a couple of tweaks might help with
> readability. The lcore 0 at the end is especially confusing. Perhaps we can
> limit the allowed formats here,
> * require the lcore_id to be specified - the lack of an lcore id for the last
> part
> makes having it as lcore 0 surprising.
> * only allow one lcore id to be given for each set of cores.
[Liang, Cunming] The last one lcore_set (0,6) without cpuset assigned is equal
to '(0,6)@(0,6)' or '0@(0,6), 6@(0,6)'.
It's not a typical use case but gives an aggressive sample, it shows the simple
way to explain the map.
>
> I think it may still be readable if we allow the core set to be omitted if its
> to be the same as the lcore_id.
>
> It's probably still not going to be very tidy, but I think we can improve
> things.
>
> /Bruce
>
> > Signed-off-by: Cunming Liang <cunming.liang at intel.com>
> > ---
> > lib/librte_eal/common/eal_common_launch.c | 1 -
> > lib/librte_eal/common/eal_common_options.c | 262
> ++++++++++++++++++++++++++++-
> > lib/librte_eal/common/eal_options.h | 2 +
> > lib/librte_eal/linuxapp/eal/Makefile | 1 +
> > 4 files changed, 261 insertions(+), 5 deletions(-)
> >
> > diff --git a/lib/librte_eal/common/eal_common_launch.c
> b/lib/librte_eal/common/eal_common_launch.c
> > index 599f83b..2d732b1 100644
> > --- a/lib/librte_eal/common/eal_common_launch.c
> > +++ b/lib/librte_eal/common/eal_common_launch.c
> > @@ -117,4 +117,3 @@ rte_eal_mp_wait_lcore(void)
> > rte_eal_wait_lcore(lcore_id);
> > }
> > }
> > -
> > diff --git a/lib/librte_eal/common/eal_common_options.c
> b/lib/librte_eal/common/eal_common_options.c
> > index e2810ab..fc47588 100644
> > --- a/lib/librte_eal/common/eal_common_options.c
> > +++ b/lib/librte_eal/common/eal_common_options.c
> > @@ -45,6 +45,7 @@
> > #include <rte_lcore.h>
> > #include <rte_version.h>
> > #include <rte_devargs.h>
> > +#include <rte_memcpy.h>
> >
> > #include "eal_internal_cfg.h"
> > #include "eal_options.h"
> > @@ -85,6 +86,7 @@ eal_long_options[] = {
> > {OPT_XEN_DOM0, 0, 0, OPT_XEN_DOM0_NUM},
> > {OPT_CREATE_UIO_DEV, 1, NULL, OPT_CREATE_UIO_DEV_NUM},
> > {OPT_VFIO_INTR, 1, NULL, OPT_VFIO_INTR_NUM},
> > + {OPT_LCORES, 1, 0, OPT_LCORES_NUM},
> > {0, 0, 0, 0}
> > };
> >
> > @@ -255,9 +257,11 @@ eal_parse_corelist(const char *corelist)
> > if (min == RTE_MAX_LCORE)
> > min = idx;
> > for (idx = min; idx <= max; idx++) {
> > - cfg->lcore_role[idx] = ROLE_RTE;
> > - lcore_config[idx].core_index = count;
> > - count++;
> > + if (cfg->lcore_role[idx] != ROLE_RTE) {
> > + cfg->lcore_role[idx] = ROLE_RTE;
> > + lcore_config[idx].core_index = count;
> > + count++;
> > + }
> > }
> > min = RTE_MAX_LCORE;
> > } else
> > @@ -289,6 +293,241 @@ eal_parse_master_lcore(const char *arg)
> > return 0;
> > }
> >
> > +/*
> > + * Parse elem, the elem could be single number or '(' ')' group
> > + * Within group elem, '-' used for a range seperator;
> > + * ',' used for a single number.
> > + */
> > +static int
> > +eal_parse_set(const char *input, uint16_t set[], unsigned num)
> > +{
> > + unsigned idx;
> > + const char *str = input;
> > + char *end = NULL;
> > + unsigned min, max;
> > +
> > + memset(set, 0, num * sizeof(uint16_t));
> > +
> > + while (isblank(*str))
> > + str++;
> > +
> > + /* only digit or left bracket is qulify for start point */
> > + if ((!isdigit(*str) && *str != '(') || *str == '\0')
> > + return -1;
> > +
> > + /* process single number */
> > + if (*str != '(') {
> > + errno = 0;
> > + idx = strtoul(str, &end, 10);
> > + if (errno || end == NULL || idx >= num)
> > + return -1;
> > + else {
> > + while (isblank(*end))
> > + end++;
> > +
> > + if (*end != ',' && *end != '\0' &&
> > + *end != '@')
> > + return -1;
> > +
> > + set[idx] = 1;
> > + return end - input;
> > + }
> > + }
> > +
> > + /* process set within bracket */
> > + str++;
> > + while (isblank(*str))
> > + str++;
> > + if (*str == '\0')
> > + return -1;
> > +
> > + min = RTE_MAX_LCORE;
> > + do {
> > +
> > + /* go ahead to the first digit */
> > + while (isblank(*str))
> > + str++;
> > + if (!isdigit(*str))
> > + return -1;
> > +
> > + /* get the digit value */
> > + errno = 0;
> > + idx = strtoul(str, &end, 10);
> > + if (errno || end == NULL || idx >= num)
> > + return -1;
> > +
> > + /* go ahead to separator '-',',' and ')' */
> > + while (isblank(*end))
> > + end++;
> > + if (*end == '-') {
> > + if (min == RTE_MAX_LCORE)
> > + min = idx;
> > + else /* avoid continuous '-' */
> > + return -1;
> > + } else if ((*end == ',') || (*end == ')')) {
> > + max = idx;
> > + if (min == RTE_MAX_LCORE)
> > + min = idx;
> > + for (idx = RTE_MIN(min, max);
> > + idx <= RTE_MAX(min, max); idx++)
> > + set[idx] = 1;
> > +
> > + min = RTE_MAX_LCORE;
> > + } else
> > + return -1;
> > +
> > + str = end + 1;
> > + } while (*end != '\0' && *end != ')');
> > +
> > + return str - input;
> > +}
> > +
> > +/* convert from set array to cpuset bitmap */
> > +static inline int
> > +convert_to_cpuset(rte_cpuset_t *cpusetp,
> > + uint16_t *set, unsigned num)
> > +{
> > + unsigned idx;
> > +
> > + CPU_ZERO(cpusetp);
> > +
> > + for (idx = 0; idx < num; idx++) {
> > + if (!set[idx])
> > + continue;
> > +
> > + if (!lcore_config[idx].detected) {
> > + RTE_LOG(ERR, EAL, "core %u "
> > + "unavailable\n", idx);
> > + return -1;
> > + }
> > +
> > + CPU_SET(idx, cpusetp);
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +/*
> > + * The format pattern: --lcores='lcores[@cpus]<,lcores[@cpus]>'
> > + * lcores, cpus could be a single digit or a group.
> > + * '(' and ')' are necessary if it's a group.
> > + * If not supply '@cpus', the value of cpus uses the same as lcores.
> > + * e.g. '1,2@(5-7),(3-5)@(0,2),(0,6)' means start 7 EAL thread as below
> > + * lcore 0 runs on cpuset 0x41 (cpu 0,6)
> > + * lcore 1 runs on cpuset 0x2 (cpu 1)
> > + * lcore 2 runs on cpuset 0xe0 (cpu 5,6,7)
> > + * lcore 3,4,5 runs on cpuset 0x5 (cpu 0,2)
> > + * lcore 6 runs on cpuset 0x41 (cpu 0,6)
> > + */
> > +static int
> > +eal_parse_lcores(const char *lcores)
> > +{
> > + struct rte_config *cfg = rte_eal_get_configuration();
> > + static uint16_t set[RTE_MAX_LCORE];
> > + unsigned idx = 0;
> > + int i;
> > + unsigned count = 0;
> > + const char *lcore_start = NULL;
> > + const char *end = NULL;
> > + int offset;
> > + rte_cpuset_t cpuset;
> > + int ret = -1;
> > +
> > + if (lcores == NULL)
> > + return -1;
> > +
> > + /* Remove all blank characters ahead and after */
> > + while (isblank(*lcores))
> > + lcores++;
> > + i = strnlen(lcores, sysconf(_SC_ARG_MAX));
> > + while ((i > 0) && isblank(lcores[i - 1]))
> > + i--;
> > +
> > + CPU_ZERO(&cpuset);
> > +
> > + /* Reset lcore config */
> > + for (idx = 0; idx < RTE_MAX_LCORE; idx++) {
> > + cfg->lcore_role[idx] = ROLE_OFF;
> > + lcore_config[idx].core_index = -1;
> > + CPU_ZERO(&lcore_config[idx].cpuset);
> > + }
> > +
> > + /* Get list of cores */
> > + do {
> > + while (isblank(*lcores))
> > + lcores++;
> > + if (*lcores == '\0')
> > + goto err;
> > +
> > + /* record lcore_set start point */
> > + lcore_start = lcores;
> > +
> > + /* go across a complete bracket */
> > + if (*lcore_start == '(') {
> > + lcores += strcspn(lcores, ")");
> > + if (*lcores++ == '\0')
> > + goto err;
> > + }
> > +
> > + /* scan the separator '@', ','(next) or '\0'(finish) */
> > + lcores += strcspn(lcores, "@,");
> > +
> > + if (*lcores == '@') {
> > + /* explict assign cpu_set */
> > + offset = eal_parse_set(lcores + 1, set, RTE_DIM(set));
> > + if (offset < 0)
> > + goto err;
> > +
> > + /* prepare cpu_set and update the end cursor */
> > + if (0 > convert_to_cpuset(&cpuset,
> > + set, RTE_DIM(set)))
> > + goto err;
> > + end = lcores + 1 + offset;
> > + } else /* ',' or '\0' */
> > + /* haven't given cpu_set, current loop done */
> > + end = lcores;
> > +
> > + if (*end != ',' && *end != '\0')
> > + goto err;
> > +
> > + /* parse lcore_set from start point */
> > + if (0 > eal_parse_set(lcore_start, set, RTE_DIM(set)))
> > + goto err;
> > +
> > + /* without '@', by default using lcore_set as cpu_set */
> > + if (*lcores != '@' &&
> > + 0 > convert_to_cpuset(&cpuset, set, RTE_DIM(set)))
> > + goto err;
> > +
> > + /* start to update lcore_set */
> > + for (idx = 0; idx < RTE_MAX_LCORE; idx++) {
> > + if (!set[idx])
> > + continue;
> > +
> > + if (cfg->lcore_role[idx] != ROLE_RTE) {
> > + lcore_config[idx].core_index = count;
> > + cfg->lcore_role[idx] = ROLE_RTE;
> > + count++;
> > + }
> > + rte_memcpy(&lcore_config[idx].cpuset, &cpuset,
> > + sizeof(rte_cpuset_t));
> > + }
> > +
> > + lcores = end + 1;
> > + } while (*end != '\0');
> > +
> > + if (count == 0)
> > + goto err;
> > +
> > + cfg->lcore_count = count;
> > + lcores_parsed = 1;
> > + ret = 0;
> > +
> > +err:
> > +
> > + return ret;
> > +}
> > +
> > static int
> > eal_parse_syslog(const char *facility, struct internal_config *conf)
> > {
> > @@ -489,6 +728,13 @@ eal_parse_common_option(int opt, const char
> *optarg,
> > conf->log_level = log;
> > break;
> > }
> > + case OPT_LCORES_NUM:
> > + if (eal_parse_lcores(optarg) < 0) {
> > + RTE_LOG(ERR, EAL, "invalid parameter for --"
> > + OPT_LCORES "\n");
> > + return -1;
> > + }
> > + break;
> >
> > /* don't know what to do, leave this to caller */
> > default:
> > @@ -527,7 +773,7 @@ eal_check_common_options(struct internal_config
> *internal_cfg)
> >
> > if (!lcores_parsed) {
> > RTE_LOG(ERR, EAL, "CPU cores must be enabled with options "
> > - "-c or -l\n");
> > + "-c, -l or --lcores\n");
> > return -1;
> > }
> > if (cfg->lcore_role[cfg->master_lcore] != ROLE_RTE) {
> > @@ -583,6 +829,14 @@ eal_common_usage(void)
> > " The argument format is
> > <c1>[-c2][,c3[-c4],...]\n"
> > " where c1, c2, etc are core indexes between 0
> and %d\n"
> > " --"OPT_MASTER_LCORE" ID: Core ID that is used as master\n"
> > + " --"OPT_LCORES" MAP: maps between lcore_set to
> phys_cpu_set\n"
> > + " The argument format is\n"
> > + " 'lcores[@cpus]<,lcores[@cpus],...>'\n"
> > + " lcores and cpus list are grouped by '(' and
> > ')'\n"
> > + " Within the group, '-' is used for range
> separator,\n"
> > + " ',' is used for single number separator.\n"
> > + " '( )' can be omitted for single element group,
> '@' \n"
> > + " can be omitted if cpus and lcores has the same
> value\n"
> > " -n NUM : Number of memory channels\n"
> > " -v : Display version information on startup\n"
> > " -m MB : memory to allocate (see also
> --"OPT_SOCKET_MEM")\n"
> > diff --git a/lib/librte_eal/common/eal_options.h
> b/lib/librte_eal/common/eal_options.h
> > index e476f8d..a1cc59f 100644
> > --- a/lib/librte_eal/common/eal_options.h
> > +++ b/lib/librte_eal/common/eal_options.h
> > @@ -77,6 +77,8 @@ enum {
> > OPT_CREATE_UIO_DEV_NUM,
> > #define OPT_VFIO_INTR "vfio-intr"
> > OPT_VFIO_INTR_NUM,
> > +#define OPT_LCORES "lcores"
> > + OPT_LCORES_NUM,
> > OPT_LONG_MAX_NUM
> > };
> >
> > diff --git a/lib/librte_eal/linuxapp/eal/Makefile
> b/lib/librte_eal/linuxapp/eal/Makefile
> > index 0e9c447..025d836 100644
> > --- a/lib/librte_eal/linuxapp/eal/Makefile
> > +++ b/lib/librte_eal/linuxapp/eal/Makefile
> > @@ -95,6 +95,7 @@ CFLAGS_eal_hugepage_info.o := -D_GNU_SOURCE
> > CFLAGS_eal_pci.o := -D_GNU_SOURCE
> > CFLAGS_eal_pci_vfio.o := -D_GNU_SOURCE
> > CFLAGS_eal_common_whitelist.o := -D_GNU_SOURCE
> > +CFLAGS_eal_common_options.o := -D_GNU_SOURCE
> >
> > # workaround for a gcc bug with noreturn attribute
> > # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12603
> > --
> > 1.8.1.4
> >