Don't generate data in sysctl_out_proc unless we intend to copy out.
The first call is used to gauge how much spaces is needed. Just computing the size instead of generating the output allows to not take the proctree lock.
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parent
7d3761dc72
commit
9d4e369ae8
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=329985
@ -1347,6 +1347,32 @@ freebsd32_kinfo_proc_out(const struct kinfo_proc *ki, struct kinfo_proc32 *ki32)
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}
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#endif
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static ssize_t
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kern_proc_out_size(struct proc *p, int flags)
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{
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ssize_t size = 0;
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PROC_LOCK_ASSERT(p, MA_OWNED);
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if ((flags & KERN_PROC_NOTHREADS) != 0) {
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#ifdef COMPAT_FREEBSD32
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if ((flags & KERN_PROC_MASK32) != 0) {
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size += sizeof(struct kinfo_proc32);
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} else
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#endif
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size += sizeof(struct kinfo_proc);
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} else {
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#ifdef COMPAT_FREEBSD32
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if ((flags & KERN_PROC_MASK32) != 0)
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size += sizeof(struct kinfo_proc32) * p->p_numthreads;
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else
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#endif
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size += sizeof(struct kinfo_proc) * p->p_numthreads;
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}
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PROC_UNLOCK(p);
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return (size);
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}
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int
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kern_proc_out(struct proc *p, struct sbuf *sb, int flags)
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{
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@ -1399,6 +1425,9 @@ sysctl_out_proc(struct proc *p, struct sysctl_req *req, int flags)
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struct kinfo_proc ki;
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int error, error2;
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if (req->oldptr == NULL)
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return (SYSCTL_OUT(req, 0, kern_proc_out_size(p, flags)));
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sbuf_new_for_sysctl(&sb, (char *)&ki, sizeof(ki), req);
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sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
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error = kern_proc_out(p, &sb, flags);
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@ -1461,16 +1490,22 @@ sysctl_kern_proc(SYSCTL_HANDLER_ARGS)
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break;
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}
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if (!req->oldptr) {
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if (req->oldptr == NULL) {
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/* overestimate by 5 procs */
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error = SYSCTL_OUT(req, 0, sizeof (struct kinfo_proc) * 5);
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if (error)
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return (error);
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}
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} else {
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error = sysctl_wire_old_buffer(req, 0);
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if (error != 0)
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return (error);
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/*
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* This lock is only needed to safely grab the parent of a
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* traced process. Only grab it if we are producing any
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* data to begin with.
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*/
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sx_slock(&proctree_lock);
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}
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sx_slock(&allproc_lock);
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for (doingzomb=0 ; doingzomb < 2 ; doingzomb++) {
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if (!doingzomb)
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@ -1571,16 +1606,15 @@ sysctl_kern_proc(SYSCTL_HANDLER_ARGS)
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}
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error = sysctl_out_proc(p, req, flags);
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if (error) {
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if (error)
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goto out;
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}
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}
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out:
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sx_sunlock(&allproc_lock);
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if (req->oldptr != NULL)
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sx_sunlock(&proctree_lock);
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return (error);
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}
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}
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}
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sx_sunlock(&allproc_lock);
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sx_sunlock(&proctree_lock);
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return (0);
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}
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struct pargs *
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