On Thu, Mar 17, 2022 at 04:07:24PM +0000, Visa Hankala wrote:
> Use the refcnt API with struct plimit.
>
> OK?
OK bluhm@
> Index: kern/kern_resource.c
> ===================================================================
> RCS file: src/sys/kern/kern_resource.c,v
> retrieving revision 1.71
> diff -u -p -r1.71 kern_resource.c
> --- kern/kern_resource.c 8 Feb 2021 10:51:01 -0000 1.71
> +++ kern/kern_resource.c 17 Mar 2022 15:59:52 -0000
> @@ -582,7 +582,7 @@ lim_startup(struct plimit *limit0)
> limit0->pl_rlimit[RLIMIT_RSS].rlim_max = lim;
> limit0->pl_rlimit[RLIMIT_MEMLOCK].rlim_max = lim;
> limit0->pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = lim / 3;
> - limit0->pl_refcnt = 1;
> + refcnt_init(&limit0->pl_refcnt);
> }
>
> /*
> @@ -598,14 +598,14 @@ lim_copy(struct plimit *lim)
> newlim = pool_get(&plimit_pool, PR_WAITOK);
> memcpy(newlim->pl_rlimit, lim->pl_rlimit,
> sizeof(struct rlimit) * RLIM_NLIMITS);
> - newlim->pl_refcnt = 1;
> + refcnt_init(&newlim->pl_refcnt);
> return (newlim);
> }
>
> void
> lim_free(struct plimit *lim)
> {
> - if (atomic_dec_int_nv(&lim->pl_refcnt) > 0)
> + if (refcnt_rele(&lim->pl_refcnt) == 0)
> return;
> pool_put(&plimit_pool, lim);
> }
> @@ -617,7 +617,7 @@ lim_fork(struct process *parent, struct
>
> mtx_enter(&parent->ps_mtx);
> limit = parent->ps_limit;
> - atomic_inc_int(&limit->pl_refcnt);
> + refcnt_take(&limit->pl_refcnt);
> mtx_leave(&parent->ps_mtx);
>
> child->ps_limit = limit;
> @@ -650,7 +650,7 @@ lim_write_begin(void)
> */
>
> limit = p->p_p->ps_limit;
> - if (P_HASSIBLING(p) || limit->pl_refcnt > 1)
> + if (P_HASSIBLING(p) || refcnt_shared(&limit->pl_refcnt))
> limit = lim_copy(limit);
>
> return (limit);
> @@ -703,7 +703,7 @@ lim_read_enter(void)
> if (limit != pr->ps_limit) {
> mtx_enter(&pr->ps_mtx);
> limit = pr->ps_limit;
> - atomic_inc_int(&limit->pl_refcnt);
> + refcnt_take(&limit->pl_refcnt);
> mtx_leave(&pr->ps_mtx);
> if (p->p_limit != NULL)
> lim_free(p->p_limit);
> Index: sys/resourcevar.h
> ===================================================================
> RCS file: src/sys/sys/resourcevar.h,v
> retrieving revision 1.24
> diff -u -p -r1.24 resourcevar.h
> --- sys/resourcevar.h 21 Jun 2019 09:39:48 -0000 1.24
> +++ sys/resourcevar.h 17 Mar 2022 15:59:52 -0000
> @@ -35,6 +35,7 @@
> #ifndef _SYS_RESOURCEVAR_H_
> #define _SYS_RESOURCEVAR_H_
>
> +#include <sys/refcnt.h>
> #include <sys/timeout.h>
>
> /*
> @@ -44,7 +45,7 @@
> */
> struct plimit {
> struct rlimit pl_rlimit[RLIM_NLIMITS];
> - u_int pl_refcnt; /* number of references */
> + struct refcnt pl_refcnt;
> };
>
> /* add user profiling from AST */
