diff options
author | jhb <jhb@FreeBSD.org> | 2004-02-04 21:52:57 +0000 |
---|---|---|
committer | jhb <jhb@FreeBSD.org> | 2004-02-04 21:52:57 +0000 |
commit | 279b2b827810d149b5b8453900cdea57874ae234 (patch) | |
tree | d9c0a05d62914174d6f00ab22300e935c3e6d983 /sys/vm/vm_pageout.c | |
parent | f7b1079809c2529c50447de59fdce77a7f5a08f5 (diff) | |
download | FreeBSD-src-279b2b827810d149b5b8453900cdea57874ae234.zip FreeBSD-src-279b2b827810d149b5b8453900cdea57874ae234.tar.gz |
Locking for the per-process resource limits structure.
- struct plimit includes a mutex to protect a reference count. The plimit
structure is treated similarly to struct ucred in that is is always copy
on write, so having a reference to a structure is sufficient to read from
it without needing a further lock.
- The proc lock protects the p_limit pointer and must be held while reading
limits from a process to keep the limit structure from changing out from
under you while reading from it.
- Various global limits that are ints are not protected by a lock since
int writes are atomic on all the archs we support and thus a lock
wouldn't buy us anything.
- All accesses to individual resource limits from a process are abstracted
behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return
either an rlimit, or the current or max individual limit of the specified
resource from a process.
- dosetrlimit() was renamed to kern_setrlimit() to match existing style of
other similar syscall helper functions.
- The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit()
(it didn't used the stackgap when it should have) but uses lim_rlimit()
and kern_setrlimit() instead.
- The svr4 compat no longer uses the stackgap for resource limits calls,
but uses lim_rlimit() and kern_setrlimit() instead.
- The ibcs2 compat no longer uses the stackgap for resource limits. It
also no longer uses the stackgap for accessing sysctl's for the
ibcs2_sysconf() syscall but uses kernel_sysctl() instead. As a result,
ibcs2_sysconf() no longer needs Giant.
- The p_rlimit macro no longer exists.
Submitted by: mtm (mostly, I only did a few cleanups and catchups)
Tested on: i386
Compiled on: alpha, amd64
Diffstat (limited to 'sys/vm/vm_pageout.c')
-rw-r--r-- | sys/vm/vm_pageout.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/sys/vm/vm_pageout.c b/sys/vm/vm_pageout.c index 471f9b3..506f1ec 100644 --- a/sys/vm/vm_pageout.c +++ b/sys/vm/vm_pageout.c @@ -1486,6 +1486,7 @@ vm_daemon() struct proc *p; int breakout; struct thread *td; + struct rlimit rsslim; mtx_lock(&Giant); while (TRUE) { @@ -1511,6 +1512,7 @@ vm_daemon() PROC_UNLOCK(p); continue; } + lim_rlimit(p, RLIMIT_RSS, &rsslim); /* * if the process is in a non-running type state, * don't touch it. @@ -1534,8 +1536,7 @@ vm_daemon() * get a limit */ limit = OFF_TO_IDX( - qmin(p->p_rlimit[RLIMIT_RSS].rlim_cur, - p->p_rlimit[RLIMIT_RSS].rlim_max)); + qmin(rsslim.rlim_cur, rsslim.rlim_max)); /* * let processes that are swapped out really be |