mirror/freebsd
1
0
Fork 0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-17 10:26:15 +00:00
Code Issues Releases Activity

Stop checking TD_IDLETHREAD() in buffer cache routines.

Browse Source 
These predicates are vestigal and cannot be true today.  For example,
idle threads are not allowed to acquire locks.

Also cache curthread in breada().

No functional change intended.

Reviewed by:	kib, mckusick
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20066
This commit is contained in:
Mark Johnston 2019-04-29 13:23:32 +00:00
parent 761618de05
commit 8e7130a8a7
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=346888
1 changed files with 21 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
sys/kern/vfs_bio.c
View File

@ -2073,8 +2073,11 @@ breada(struct vnode * vp, daddr_t * rablkno, int * rabsize, int cnt,
struct ucred * cred, int flags, void (*ckhashfunc)(struct buf *))
{
struct buf *rabp;
struct thread *td;
int i;
td = curthread;
for (i = 0; i < cnt; i++, rablkno++, rabsize++) {
if (inmem(vp, *rablkno))
continue;
@ -2083,16 +2086,14 @@ breada(struct vnode * vp, daddr_t * rablkno, int * rabsize, int cnt,
brelse(rabp);
continue;
}
if (!TD_IS_IDLETHREAD(curthread)) {
#ifdef RACCT
if (racct_enable) {
PROC_LOCK(curproc);
racct_add_buf(curproc, rabp, 0);
PROC_UNLOCK(curproc);
}
#endif /* RACCT */
curthread->td_ru.ru_inblock++;
if (racct_enable) {
PROC_LOCK(curproc);
racct_add_buf(curproc, rabp, 0);
PROC_UNLOCK(curproc);
}
#endif /* RACCT */
td->td_ru.ru_inblock++;
rabp->b_flags |= B_ASYNC;
rabp->b_flags &= ~B_INVAL;
if ((flags & GB_CKHASH) != 0) {
@ -2148,16 +2149,14 @@ breadn_flags(struct vnode *vp, daddr_t blkno, int size, daddr_t *rablkno,
*/
readwait = 0;
if ((bp->b_flags & B_CACHE) == 0) {
if (!TD_IS_IDLETHREAD(td)) {
#ifdef RACCT
if (racct_enable) {
PROC_LOCK(td->td_proc);
racct_add_buf(td->td_proc, bp, 0);
PROC_UNLOCK(td->td_proc);
}
#endif /* RACCT */
td->td_ru.ru_inblock++;
if (racct_enable) {
PROC_LOCK(td->td_proc);
racct_add_buf(td->td_proc, bp, 0);
PROC_UNLOCK(td->td_proc);
}
#endif /* RACCT */
td->td_ru.ru_inblock++;
bp->b_iocmd = BIO_READ;
bp->b_flags &= ~B_INVAL;
if ((flags & GB_CKHASH) != 0) {
@ -2258,16 +2257,14 @@ bufwrite(struct buf *bp)
bp->b_runningbufspace = bp->b_bufsize;
space = atomic_fetchadd_long(&runningbufspace, bp->b_runningbufspace);
if (!TD_IS_IDLETHREAD(curthread)) {
#ifdef RACCT
if (racct_enable) {
PROC_LOCK(curproc);
racct_add_buf(curproc, bp, 1);
PROC_UNLOCK(curproc);
}
#endif /* RACCT */
curthread->td_ru.ru_oublock++;
if (racct_enable) {
PROC_LOCK(curproc);
racct_add_buf(curproc, bp, 1);
PROC_UNLOCK(curproc);
}
#endif /* RACCT */
curthread->td_ru.ru_oublock++;
if (oldflags & B_ASYNC)
BUF_KERNPROC(bp);
bp->b_iooffset = dbtob(bp->b_blkno);
@ -4019,9 +4016,6 @@ getblkx(struct vnode *vp, daddr_t blkno, int size, int slpflag, int slptimeo,
*/
if (flags & GB_NOCREAT)
return (EEXIST);
if (bdomain[bo->bo_domain].bd_freebuffers == 0 &&
TD_IS_IDLETHREAD(curthread))
return (EBUSY);
bsize = vn_isdisk(vp, NULL) ? DEV_BSIZE : bo->bo_bsize;
KASSERT(bsize != 0, ("bsize == 0, check bo->bo_bsize"));