David Marchand <david.march...@redhat.com> writes:
> Subject: Re: [PATCH v2 1/4] eal: use C11 atomic builtins for already
> initialized
> check
>
> On Wed, Sep 16, 2020 at 10:24 AM Phil Yang <phil.y...@arm.com> wrote:
> >
> > Since rte_atomicXX APIs are not allowed to be used, use C11 builtins to
> > check if EAL is already initialized.
> >
> > Signed-off-by: Phil Yang <phil.y...@arm.com>
> > Reviewed-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>
> > Reviewed-by: Ruifeng Wang <ruifeng.w...@arm.com>
> > ---
> > lib/librte_eal/freebsd/eal.c | 18 ++++++++++--------
> > lib/librte_eal/linux/eal.c | 20 +++++++++++---------
> > 2 files changed, 21 insertions(+), 17 deletions(-)
> >
> > diff --git a/lib/librte_eal/freebsd/eal.c b/lib/librte_eal/freebsd/eal.c
> > index 798add0..9f4c7bb 100644
> > --- a/lib/librte_eal/freebsd/eal.c
> > +++ b/lib/librte_eal/freebsd/eal.c
> > @@ -665,7 +665,8 @@ rte_eal_init(int argc, char **argv)
> > {
> > int i, fctret, ret;
> > pthread_t thread_id;
> > - static rte_atomic32_t run_once = RTE_ATOMIC32_INIT(0);
> > + static uint32_t run_once;
> > + uint32_t has_run = 0;
> > char cpuset[RTE_CPU_AFFINITY_STR_LEN];
> > char thread_name[RTE_MAX_THREAD_NAME_LEN];
> > const struct rte_config *config = rte_eal_get_configuration();
> > @@ -679,7 +680,8 @@ rte_eal_init(int argc, char **argv)
> > return -1;
> > }
> >
> > - if (!rte_atomic32_test_and_set(&run_once)) {
> > + if (!__atomic_compare_exchange_n(&run_once, &has_run, 1, 0,
> > + __ATOMIC_RELAXED,
> > __ATOMIC_RELAXED)) {
> > rte_eal_init_alert("already called initialization.");
> > rte_errno = EALREADY;
> > return -1;
> > @@ -705,7 +707,7 @@ rte_eal_init(int argc, char **argv)
> > if (fctret < 0) {
> > rte_eal_init_alert("Invalid 'command line' arguments.");
> > rte_errno = EINVAL;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > @@ -715,20 +717,20 @@ rte_eal_init(int argc, char **argv)
> > if (eal_plugins_init() < 0) {
> > rte_eal_init_alert("Cannot init plugins");
> > rte_errno = EINVAL;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > if (eal_trace_init() < 0) {
> > rte_eal_init_alert("Cannot init trace");
> > rte_errno = EFAULT;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > if (eal_option_device_parse()) {
> > rte_errno = ENODEV;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > @@ -762,7 +764,7 @@ rte_eal_init(int argc, char **argv)
> > if (rte_bus_scan()) {
> > rte_eal_init_alert("Cannot scan the buses for devices");
> > rte_errno = ENODEV;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > @@ -790,7 +792,7 @@ rte_eal_init(int argc, char **argv)
> > if (ret < 0) {
> > rte_eal_init_alert("Cannot get hugepage
> > information.");
> > rte_errno = EACCES;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> > }
> > diff --git a/lib/librte_eal/linux/eal.c b/lib/librte_eal/linux/eal.c
> > index 0960f01..82a73ed 100644
> > --- a/lib/librte_eal/linux/eal.c
> > +++ b/lib/librte_eal/linux/eal.c
> > @@ -960,7 +960,8 @@ rte_eal_init(int argc, char **argv)
> > {
> > int i, fctret, ret;
> > pthread_t thread_id;
> > - static rte_atomic32_t run_once = RTE_ATOMIC32_INIT(0);
> > + static uint32_t run_once;
> > + uint32_t has_run = 0;
> > const char *p;
> > static char logid[PATH_MAX];
> > char cpuset[RTE_CPU_AFFINITY_STR_LEN];
> > @@ -977,7 +978,8 @@ rte_eal_init(int argc, char **argv)
> > return -1;
> > }
> >
> > - if (!rte_atomic32_test_and_set(&run_once)) {
> > + if (!__atomic_compare_exchange_n(&run_once, &has_run, 1, 0,
> > + __ATOMIC_RELAXED,
> > __ATOMIC_RELAXED)) {
> > rte_eal_init_alert("already called initialization.");
> > rte_errno = EALREADY;
> > return -1;
> > @@ -1005,14 +1007,14 @@ rte_eal_init(int argc, char **argv)
> > if (fctret < 0) {
> > rte_eal_init_alert("Invalid 'command line' arguments.");
> > rte_errno = EINVAL;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > if (eal_plugins_init() < 0) {
> > rte_eal_init_alert("Cannot init plugins");
> > rte_errno = EINVAL;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > @@ -1024,7 +1026,7 @@ rte_eal_init(int argc, char **argv)
> >
> > if (eal_option_device_parse()) {
> > rte_errno = ENODEV;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > @@ -1064,7 +1066,7 @@ rte_eal_init(int argc, char **argv)
> > if (rte_bus_scan()) {
> > rte_eal_init_alert("Cannot scan the buses for devices");
> > rte_errno = ENODEV;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > @@ -1138,7 +1140,7 @@ rte_eal_init(int argc, char **argv)
> > if (ret < 0) {
> > rte_eal_init_alert("Cannot get hugepage
> > information.");
> > rte_errno = EACCES;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> > }
> > @@ -1162,7 +1164,7 @@ rte_eal_init(int argc, char **argv)
> > if (rte_eal_log_init(logid, internal_conf->syslog_facility) < 0) {
> > rte_eal_init_alert("Cannot init logging.");
> > rte_errno = ENOMEM;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> >
> > @@ -1170,7 +1172,7 @@ rte_eal_init(int argc, char **argv)
> > if (rte_eal_vfio_setup() < 0) {
> > rte_eal_init_alert("Cannot init VFIO");
> > rte_errno = EAGAIN;
> > - rte_atomic32_clear(&run_once);
> > + __atomic_store_n(&run_once, 0, __ATOMIC_RELAXED);
> > return -1;
> > }
> > #endif
> > --
> > 2.7.4
> >
>
> I see no reason to include rte_atomic.h in those files after this patch.
> Did I miss something?
No, it is not needed anymore.
Will remove them.
Thanks,
Phil
>
>
> --
> David Marchand
