Applied, thanks!
Milos Nikic, le dim. 01 mars 2026 22:23:09 -0800, a ecrit:
> The convert_port_to_* functions are heavily utilized fast paths.
> Add `likely(IP_VALID(port))` hints to optimize the instruction
> cache for the standard happy path where the provided IPC port
> is valid.
>
> Also added a few targeted branch hints to the active/null checks
> in processor_set_default and ipc_pset_enable.
>
> Tested by recompiling and booting inside QEMU on x86_64.
>
> * kern/ipc_host.c (ipc_pset_enable, processor_set_default,
> convert_port_to_host, convert_port_to_host_priv,
> convert_port_to_processor, convert_port_to_pset,
> convert_port_to_pset_name): Use likely and unlikely macros.
> ---
> kern/ipc_host.c | 15 ++++++++-------
> 1 file changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/kern/ipc_host.c b/kern/ipc_host.c
> index 4c6c530..d033b2e 100644
> --- a/kern/ipc_host.c
> +++ b/kern/ipc_host.c
> @@ -36,6 +36,7 @@
> #include <kern/debug.h>
> #include <kern/host.h>
> #include <kern/mach_host.server.h>
> +#include <kern/macros.h>
> #include <kern/processor.h>
> #include <kern/task.h>
> #include <kern/thread.h>
> @@ -159,7 +160,7 @@ ipc_pset_enable(
> processor_set_t pset)
> {
> pset_lock(pset);
> - if (pset->active) {
> + if (likely(pset->active)) {
> ipc_kobject_set(pset->pset_self,
> (ipc_kobject_t) pset, IKOT_PSET);
> ipc_kobject_set(pset->pset_name_self,
> @@ -210,7 +211,7 @@ processor_set_default(
> const host_t host,
> processor_set_t *pset)
> {
> - if (host == HOST_NULL)
> + if (unlikely(host == HOST_NULL))
> return KERN_INVALID_ARGUMENT;
>
> *pset = &default_pset;
> @@ -233,7 +234,7 @@ convert_port_to_host(
> {
> host_t host = HOST_NULL;
>
> - if (IP_VALID(port)) {
> + if (likely(IP_VALID(port))) {
> ip_lock(port);
> if (ip_active(port) &&
> ((ip_kotype(port) == IKOT_HOST) ||
> @@ -260,7 +261,7 @@ convert_port_to_host_priv(
> {
> host_t host = HOST_NULL;
>
> - if (IP_VALID(port)) {
> + if (likely(IP_VALID(port))) {
> ip_lock(port);
> if (ip_active(port) &&
> (ip_kotype(port) == IKOT_HOST_PRIV))
> @@ -287,7 +288,7 @@ convert_port_to_processor(
> {
> processor_t processor = PROCESSOR_NULL;
>
> - if (IP_VALID(port)) {
> + if (likely(IP_VALID(port))) {
> ip_lock(port);
> if (ip_active(port) &&
> (ip_kotype(port) == IKOT_PROCESSOR))
> @@ -314,7 +315,7 @@ convert_port_to_pset(
> {
> processor_set_t pset = PROCESSOR_SET_NULL;
>
> - if (IP_VALID(port)) {
> + if (likely(IP_VALID(port))) {
> ip_lock(port);
> if (ip_active(port) &&
> (ip_kotype(port) == IKOT_PSET)) {
> @@ -343,7 +344,7 @@ convert_port_to_pset_name(
> {
> processor_set_t pset = PROCESSOR_SET_NULL;
>
> - if (IP_VALID(port)) {
> + if (likely(IP_VALID(port))) {
> ip_lock(port);
> if (ip_active(port) &&
> ((ip_kotype(port) == IKOT_PSET) ||
> --
> 2.53.0
>
>
--
Samuel
<T> csp.tar.gz: ascii text
-+- #ens-mim - vive les browsers qui prennent des initiatives à la con -+-
