Author: kib
Date: Mon Mar 16 11:40:59 2020
New Revision: 359012
URL: https://svnweb.freebsd.org/changeset/base/359012
Log:
MFC r358825:
Preallocate pipe buffers on pipe creation.
Modified:
stable/12/sys/fs/fifofs/fifo_vnops.c
stable/12/sys/kern/sys_pipe.c
stable/12/sys/sys/pipe.h
Directory Properties:
stable/12/ (props changed)
Modified: stable/12/sys/fs/fifofs/fifo_vnops.c
==============================================================================
--- stable/12/sys/fs/fifofs/fifo_vnops.c Mon Mar 16 11:38:26 2020 (r359011)
+++ stable/12/sys/fs/fifofs/fifo_vnops.c Mon Mar 16 11:40:59 2020 (r359012)
@@ -150,7 +150,9 @@ fifo_open(ap)
if (fp == NULL || (ap->a_mode & FEXEC) != 0)
return (EINVAL);
if ((fip = vp->v_fifoinfo) == NULL) {
- pipe_named_ctor(&fpipe, td);
+ error = pipe_named_ctor(&fpipe, td);
+ if (error != 0)
+ return (error);
fip = malloc(sizeof(*fip), M_VNODE, M_WAITOK);
fip->fi_pipe = fpipe;
fpipe->pipe_wgen = fip->fi_readers = fip->fi_writers = 0;
Modified: stable/12/sys/kern/sys_pipe.c
==============================================================================
--- stable/12/sys/kern/sys_pipe.c Mon Mar 16 11:38:26 2020 (r359011)
+++ stable/12/sys/kern/sys_pipe.c Mon Mar 16 11:40:59 2020 (r359012)
@@ -226,8 +226,8 @@ SYSCTL_INT(_kern_ipc, OID_AUTO, piperesizeallowed, CTL
static void pipeinit(void *dummy __unused);
static void pipeclose(struct pipe *cpipe);
static void pipe_free_kmem(struct pipe *cpipe);
-static void pipe_create(struct pipe *pipe, int backing);
-static void pipe_paircreate(struct thread *td, struct pipepair **p_pp);
+static int pipe_create(struct pipe *pipe, bool backing);
+static int pipe_paircreate(struct thread *td, struct pipepair **p_pp);
static __inline int pipelock(struct pipe *cpipe, int catch);
static __inline void pipeunlock(struct pipe *cpipe);
#ifndef PIPE_NODIRECT
@@ -335,11 +335,12 @@ pipe_zone_fini(void *mem, int size)
mtx_destroy(&pp->pp_mtx);
}
-static void
+static int
pipe_paircreate(struct thread *td, struct pipepair **p_pp)
{
struct pipepair *pp;
struct pipe *rpipe, *wpipe;
+ int error;
*p_pp = pp = uma_zalloc(pipe_zone, M_WAITOK);
#ifdef MAC
@@ -357,22 +358,44 @@ pipe_paircreate(struct thread *td, struct pipepair **p
knlist_init_mtx(&rpipe->pipe_sel.si_note, PIPE_MTX(rpipe));
knlist_init_mtx(&wpipe->pipe_sel.si_note, PIPE_MTX(wpipe));
- /* Only the forward direction pipe is backed by default */
- pipe_create(rpipe, 1);
- pipe_create(wpipe, 0);
+ /*
+ * Only the forward direction pipe is backed by big buffer by
+ * default.
+ */
+ error = pipe_create(rpipe, true);
+ if (error != 0)
+ goto fail;
+ error = pipe_create(wpipe, false);
+ if (error != 0) {
+ pipe_free_kmem(rpipe);
+ goto fail;
+ }
rpipe->pipe_state |= PIPE_DIRECTOK;
wpipe->pipe_state |= PIPE_DIRECTOK;
+ return (0);
+
+fail:
+ knlist_destroy(&rpipe->pipe_sel.si_note);
+ knlist_destroy(&wpipe->pipe_sel.si_note);
+#ifdef MAC
+ mac_pipe_destroy(pp);
+#endif
+ return (error);
}
-void
+int
pipe_named_ctor(struct pipe **ppipe, struct thread *td)
{
struct pipepair *pp;
+ int error;
- pipe_paircreate(td, &pp);
+ error = pipe_paircreate(td, &pp);
+ if (error != 0)
+ return (error);
pp->pp_rpipe.pipe_state |= PIPE_NAMED;
*ppipe = &pp->pp_rpipe;
+ return (0);
}
void
@@ -404,7 +427,9 @@ kern_pipe(struct thread *td, int fildes[2], int flags,
struct pipepair *pp;
int fd, fflags, error;
- pipe_paircreate(td, &pp);
+ error = pipe_paircreate(td, &pp);
+ if (error != 0)
+ return (error);
rpipe = &pp->pp_rpipe;
wpipe = &pp->pp_wpipe;
error = falloc_caps(td, &rf, &fd, flags, fcaps1);
@@ -618,25 +643,16 @@ pipeselwakeup(struct pipe *cpipe)
* Initialize and allocate VM and memory for pipe. The structure
* will start out zero'd from the ctor, so we just manage the kmem.
*/
-static void
-pipe_create(struct pipe *pipe, int backing)
+static int
+pipe_create(struct pipe *pipe, bool large_backing)
{
+ int error;
- if (backing) {
- /*
- * Note that these functions can fail if pipe map is exhausted
- * (as a result of too many pipes created), but we ignore the
- * error as it is not fatal and could be provoked by
- * unprivileged users. The only consequence is worse performance
- * with given pipe.
- */
- if (amountpipekva > maxpipekva / 2)
- (void)pipespace_new(pipe, SMALL_PIPE_SIZE);
- else
- (void)pipespace_new(pipe, PIPE_SIZE);
- }
-
- pipe->pipe_ino = alloc_unr64(&pipeino_unr);
+ error = pipespace_new(pipe, !large_backing || amountpipekva >
+ maxpipekva / 2 ? SMALL_PIPE_SIZE : PIPE_SIZE);
+ if (error == 0)
+ pipe->pipe_ino = alloc_unr64(&pipeino_unr);
+ return (error);
}
/* ARGSUSED */
@@ -1070,17 +1086,7 @@ pipe_write(struct file *fp, struct uio *uio, struct uc
pipespace(wpipe, desiredsize);
PIPE_LOCK(wpipe);
}
- if (wpipe->pipe_buffer.size == 0) {
- /*
- * This can only happen for reverse direction use of pipes
- * in a complete OOM situation.
- */
- error = ENOMEM;
- --wpipe->pipe_busy;
- pipeunlock(wpipe);
- PIPE_UNLOCK(wpipe);
- return (error);
- }
+ MPASS(wpipe->pipe_buffer.size != 0);
pipeunlock(wpipe);
Modified: stable/12/sys/sys/pipe.h
==============================================================================
--- stable/12/sys/sys/pipe.h Mon Mar 16 11:38:26 2020 (r359011)
+++ stable/12/sys/sys/pipe.h Mon Mar 16 11:40:59 2020 (r359012)
@@ -142,6 +142,6 @@ struct pipepair {
#define PIPE_LOCK_ASSERT(pipe, type) mtx_assert(PIPE_MTX(pipe), (type))
void pipe_dtor(struct pipe *dpipe);
-void pipe_named_ctor(struct pipe **ppipe, struct thread *td);
+int pipe_named_ctor(struct pipe **ppipe, struct thread *td);
void pipeselwakeup(struct pipe *cpipe);
#endif /* !_SYS_PIPE_H_ */