diff options
| -rw-r--r-- | sys/compat/svr4/svr4_misc.c | 3 | ||||
| -rw-r--r-- | sys/kern/kern_exec.c | 8 | ||||
| -rw-r--r-- | sys/kern/kern_exit.c | 3 | ||||
| -rw-r--r-- | sys/kern/kern_fork.c | 3 | ||||
| -rw-r--r-- | sys/kern/kern_proc.c | 12 | ||||
| -rw-r--r-- | sys/sys/proc.h | 51 |
6 files changed, 61 insertions, 19 deletions
diff --git a/sys/compat/svr4/svr4_misc.c b/sys/compat/svr4/svr4_misc.c index 33c679a..3780fd0 100644 --- a/sys/compat/svr4/svr4_misc.c +++ b/sys/compat/svr4/svr4_misc.c @@ -1330,8 +1330,7 @@ loop: /* * Remove unused arguments */ - if (q->p_args && --q->p_args->ar_ref == 0) - FREE(q->p_args, M_PARGS); + pargs_drop(q->p_args); PROC_UNLOCK(q); /* diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c index 8e88de6..fe0be73 100644 --- a/sys/kern/kern_exec.c +++ b/sys/kern/kern_exec.c @@ -441,8 +441,7 @@ interpret: pa = p->p_args; p->p_args = NULL; PROC_UNLOCK(p); - if (pa != NULL && --pa->ar_ref == 0) - FREE(pa, M_PARGS); + pargs_drop(pa); /* Set values passed into the program in registers. */ setregs(td, imgp->entry_addr, (u_long)(uintptr_t)stack_base, @@ -451,10 +450,7 @@ interpret: /* Cache arguments if they fit inside our allowance */ i = imgp->endargs - imgp->stringbase; if (ps_arg_cache_limit >= i + sizeof(struct pargs)) { - MALLOC(pa, struct pargs *, sizeof(struct pargs) + i, - M_PARGS, M_WAITOK); - pa->ar_ref = 1; - pa->ar_length = i; + pa = pargs_alloc(i); bcopy(imgp->stringbase, pa->ar_args, i); PROC_LOCK(p); p->p_args = pa; diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c index 6e38fd0..172fd10 100644 --- a/sys/kern/kern_exit.c +++ b/sys/kern/kern_exit.c @@ -637,8 +637,7 @@ loop: /* * Remove unused arguments */ - if (p->p_args && --p->p_args->ar_ref == 0) - FREE(p->p_args, M_PARGS); + pargs_drop(p->p_args); if (--p->p_procsig->ps_refcnt == 0) { if (p->p_sigacts != &p->p_uarea->u_sigacts) diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c index db4a459..ddd962a 100644 --- a/sys/kern/kern_fork.c +++ b/sys/kern/kern_fork.c @@ -482,8 +482,7 @@ again: p2->p_ucred = crhold(p1->p_ucred); td2->td_ucred = crhold(p2->p_ucred); /* XXXKSE */ - if (p2->p_args) - p2->p_args->ar_ref++; + pargs_hold(p2->p_args); if (flags & RFSIGSHARE) { p2->p_procsig = p1->p_procsig; diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c index 0e236cb..b81141b 100644 --- a/sys/kern/kern_proc.c +++ b/sys/kern/kern_proc.c @@ -80,6 +80,7 @@ struct proclist zombproc; struct sx allproc_lock; struct sx proctree_lock; struct sx pgrpsess_lock; +struct mtx pargs_ref_lock; uma_zone_t proc_zone; uma_zone_t ithread_zone; @@ -94,6 +95,7 @@ procinit() sx_init(&allproc_lock, "allproc"); sx_init(&proctree_lock, "proctree"); sx_init(&pgrpsess_lock, "pgrpsess"); + mtx_init(&pargs_ref_lock, "struct pargs.ref", MTX_DEF); LIST_INIT(&allproc); LIST_INIT(&zombproc); pidhashtbl = hashinit(maxproc / 4, M_PROC, &pidhash); @@ -982,23 +984,19 @@ sysctl_kern_proc_args(SYSCTL_HANDLER_ARGS) pa = p->p_args; p->p_args = NULL; PROC_UNLOCK(p); - if (pa != NULL && --pa->ar_ref == 0) - FREE(pa, M_PARGS); + pargs_drop(pa); if (req->newlen + sizeof(struct pargs) > ps_arg_cache_limit) return (error); - MALLOC(pa, struct pargs *, sizeof(struct pargs) + req->newlen, - M_PARGS, M_WAITOK); - pa->ar_ref = 1; - pa->ar_length = req->newlen; + pa = pargs_alloc(req->newlen); error = SYSCTL_IN(req, pa->ar_args, req->newlen); if (!error) { PROC_LOCK(p); p->p_args = pa; PROC_UNLOCK(p); } else - FREE(pa, M_PARGS); + pargs_free(pa); return (error); } diff --git a/sys/sys/proc.h b/sys/sys/proc.h index e3e0cf8..d520d63 100644 --- a/sys/sys/proc.h +++ b/sys/sys/proc.h @@ -55,6 +55,8 @@ #else #include <sys/pcpu.h> #endif +#include <sys/lock.h> +#include <sys/mutex.h> #include <sys/ucred.h> #include <machine/proc.h> /* Machine-dependent proc substruct. */ #include <vm/uma.h> @@ -667,6 +669,10 @@ sigonstack(size_t sp) (--(p)->p_lock); \ } while (0) +/* Lock and unlock process arguments. */ +#define PARGS_LOCK(p) mtx_lock(&pargs_ref_lock) +#define PARGS_UNLOCK(p) mtx_unlock(&pargs_ref_lock) + #define PIDHASH(pid) (&pidhashtbl[(pid) & pidhash]) extern LIST_HEAD(pidhashhead, proc) *pidhashtbl; extern u_long pidhash; @@ -678,6 +684,7 @@ extern u_long pgrphash; extern struct sx allproc_lock; extern struct sx proctree_lock; extern struct sx pgrpsess_lock; +extern struct mtx pargs_ref_lock; extern struct proc proc0; /* Process slot for swapper. */ extern struct thread thread0; /* Primary thread in proc0 */ extern int hogticks; /* Limit on kernel cpu hogs. */ @@ -700,6 +707,50 @@ extern uma_zone_t proc_zone; extern int lastpid; +static __inline struct pargs * +pargs_alloc(int len) +{ + struct pargs *pa; + + MALLOC(pa, struct pargs *, sizeof(struct pargs) + len, M_PARGS, + M_WAITOK); + pa->ar_ref = 1; + pa->ar_length = len; + return (pa); +} + +static __inline void +pargs_free(struct pargs *pa) +{ + + FREE(pa, M_PARGS); +} + +static __inline void +pargs_hold(struct pargs *pa) +{ + + if (pa == NULL) + return; + PARGS_LOCK(pa); + pa->ar_ref++; + PARGS_UNLOCK(pa); +} + +static __inline void +pargs_drop(struct pargs *pa) +{ + + if (pa == NULL) + return; + PARGS_LOCK(pa); + if (--pa->ar_ref == 0) { + PARGS_UNLOCK(pa); + pargs_free(pa); + } else + PARGS_UNLOCK(pa); +} + /* * XXX macros for scheduler. Shouldn't be here, but currently needed for * bounding the dubious p_estcpu inheritance in wait1(). |
