The branch main has been updated by markj:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=e24a65528388f4debfb12e936f314f85ba6ac407

commit e24a65528388f4debfb12e936f314f85ba6ac407
Author:     Mark Johnston <[email protected]>
AuthorDate: 2024-07-29 01:40:22 +0000
Commit:     Mark Johnston <[email protected]>
CommitDate: 2024-07-29 01:40:22 +0000

    thread: Remove kernel stack swapping support, part 4
    
    - Remove the IS_SWAPPED thread inhibitor state.
    - Remove all uses of TD_IS_SWAPPED() in the kernel.
    - Remove the TDF_CANSWAP flag.
    - Remove the P_SWAPPINGOUT and P_SWAPPINGIN flags.
    
    Tested by:      pho
    Reviewed by:    alc, imp, kib
    Differential Revision:  https://reviews.freebsd.org/D46115
---
 sys/arm/arm/stack_machdep.c         |  2 --
 sys/arm64/arm64/stack_machdep.c     |  2 --
 sys/ddb/db_ps.c                     |  8 --------
 sys/gdb/gdb_main.c                  |  2 --
 sys/kern/kern_proc.c                | 10 +++-------
 sys/kern/kern_sig.c                 | 13 ++-----------
 sys/kern/kern_synch.c               | 25 +++++--------------------
 sys/kern/sched_4bsd.c               |  3 ---
 sys/kern/sched_ule.c                |  3 ---
 sys/kern/tty_info.c                 |  8 ++------
 sys/powerpc/powerpc/stack_machdep.c |  2 --
 sys/riscv/riscv/stack_machdep.c     |  2 --
 sys/sys/proc.h                      | 19 +++++--------------
 sys/sys/user.h                      |  2 +-
 sys/vm/vm_meter.c                   |  4 +---
 sys/vm/vm_pageout.c                 |  3 +--
 sys/x86/x86/stack_machdep.c         |  2 --
 17 files changed, 20 insertions(+), 90 deletions(-)

diff --git a/sys/arm/arm/stack_machdep.c b/sys/arm/arm/stack_machdep.c
index 3fc42d4524ae..7dcf5583d866 100644
--- a/sys/arm/arm/stack_machdep.c
+++ b/sys/arm/arm/stack_machdep.c
@@ -69,8 +69,6 @@ stack_save_td(struct stack *st, struct thread *td)
        struct unwind_state state;
 
        THREAD_LOCK_ASSERT(td, MA_OWNED);
-       KASSERT(!TD_IS_SWAPPED(td),
-           ("stack_save_td: thread %p is swapped", td));
 
        if (TD_IS_RUNNING(td))
                return (EOPNOTSUPP);
diff --git a/sys/arm64/arm64/stack_machdep.c b/sys/arm64/arm64/stack_machdep.c
index e5e105aeb955..fde975ffc7d2 100644
--- a/sys/arm64/arm64/stack_machdep.c
+++ b/sys/arm64/arm64/stack_machdep.c
@@ -59,8 +59,6 @@ stack_save_td(struct stack *st, struct thread *td)
        struct unwind_state frame;
 
        THREAD_LOCK_ASSERT(td, MA_OWNED);
-       KASSERT(!TD_IS_SWAPPED(td),
-           ("stack_save_td: thread %p is swapped", td));
 
        if (TD_IS_RUNNING(td))
                return (EOPNOTSUPP);
diff --git a/sys/ddb/db_ps.c b/sys/ddb/db_ps.c
index cc2eded87c77..9bccb46f989c 100644
--- a/sys/ddb/db_ps.c
+++ b/sys/ddb/db_ps.c
@@ -290,8 +290,6 @@ dumpthread(volatile struct proc *p, volatile struct thread 
*td, int all)
                                else
                                        strlcat(state, "D", sizeof(state));
                        }
-                       if (TD_IS_SWAPPED(td))
-                               strlcat(state, "W", sizeof(state));
                        if (TD_AWAITING_INTR(td))
                                strlcat(state, "I", sizeof(state));
                        if (TD_IS_SUSPENDED(td))
@@ -393,12 +391,6 @@ DB_SHOW_COMMAND(thread, db_show_thread)
                        db_printf("SUSPENDED");
                        comma = true;
                }
-               if (TD_IS_SWAPPED(td)) {
-                       if (comma)
-                               db_printf(", ");
-                       db_printf("SWAPPED");
-                       comma = true;
-               }
                if (TD_ON_LOCK(td)) {
                        if (comma)
                                db_printf(", ");
diff --git a/sys/gdb/gdb_main.c b/sys/gdb/gdb_main.c
index 3e8ada42adac..8ba8b14fd4b1 100644
--- a/sys/gdb/gdb_main.c
+++ b/sys/gdb/gdb_main.c
@@ -522,8 +522,6 @@ do_qXfer_threads_read(void)
                                sbuf_cat(&ctx.qXfer.sb, "Blocked");
                        else if (TD_IS_SLEEPING(ctx.iter))
                                sbuf_cat(&ctx.qXfer.sb, "Sleeping");
-                       else if (TD_IS_SWAPPED(ctx.iter))
-                               sbuf_cat(&ctx.qXfer.sb, "Swapped");
                        else if (TD_AWAITING_INTR(ctx.iter))
                                sbuf_cat(&ctx.qXfer.sb, "IthreadWait");
                        else if (TD_IS_SUSPENDED(ctx.iter))
diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c
index 52b361832218..280ad3facd3a 100644
--- a/sys/kern/kern_proc.c
+++ b/sys/kern/kern_proc.c
@@ -1140,10 +1140,8 @@ fill_kinfo_proc_only(struct proc *p, struct kinfo_proc 
*kp)
 
                kp->ki_size = vm->vm_map.size;
                kp->ki_rssize = vmspace_resident_count(vm); /*XXX*/
-               FOREACH_THREAD_IN_PROC(p, td0) {
-                       if (!TD_IS_SWAPPED(td0))
-                               kp->ki_rssize += td0->td_kstack_pages;
-               }
+               FOREACH_THREAD_IN_PROC(p, td0)
+                       kp->ki_rssize += td0->td_kstack_pages;
                kp->ki_swrss = vm->vm_swrss;
                kp->ki_tsize = vm->vm_tsize;
                kp->ki_dsize = vm->vm_dsize;
@@ -2869,9 +2867,7 @@ sysctl_kern_proc_kstack(SYSCTL_HANDLER_ARGS)
                    sizeof(kkstp->kkst_trace), SBUF_FIXEDLEN);
                thread_lock(td);
                kkstp->kkst_tid = td->td_tid;
-               if (TD_IS_SWAPPED(td))
-                       kkstp->kkst_state = KKST_STATE_SWAPPED;
-               else if (stack_save_td(st, td) == 0)
+               if (stack_save_td(st, td) == 0)
                        kkstp->kkst_state = KKST_STATE_STACKOK;
                else
                        kkstp->kkst_state = KKST_STATE_RUNNING;
diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index 7ac9dcb8cb40..46f7b29837e4 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -2791,8 +2791,7 @@ sig_suspend_threads(struct thread *td, struct proc *p)
        FOREACH_THREAD_IN_PROC(p, td2) {
                thread_lock(td2);
                ast_sched_locked(td2, TDA_SUSPEND);
-               if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
-                   (td2->td_flags & TDF_SINTR)) {
+               if (TD_IS_SLEEPING(td2) && (td2->td_flags & TDF_SINTR) != 0) {
                        if (td2->td_flags & TDF_SBDRY) {
                                /*
                                 * Once a thread is asleep with
@@ -3579,16 +3578,8 @@ proc_wkilled(struct proc *p)
 {
 
        PROC_LOCK_ASSERT(p, MA_OWNED);
-       if ((p->p_flag & P_WKILLED) == 0) {
+       if ((p->p_flag & P_WKILLED) == 0)
                p->p_flag |= P_WKILLED;
-               /*
-                * Notify swapper that there is a process to swap in.
-                * The notification is racy, at worst it would take 10
-                * seconds for the swapper process to notice.
-                */
-               if ((p->p_flag & (P_INMEM | P_SWAPPINGIN)) == 0)
-                       wakeup(&proc0);
-       }
 }
 
 /*
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c
index c7258b3cffa5..25bca094b400 100644
--- a/sys/kern/kern_synch.c
+++ b/sys/kern/kern_synch.c
@@ -558,25 +558,23 @@ mi_switch(int flags)
 }
 
 /*
- * Change thread state to be runnable, placing it on the run queue if
- * it is in memory.  If it is swapped out, return true so our caller
- * will know to awaken the swapper.
+ * Change thread state to be runnable, placing it on the run queue.
  *
  * Requires the thread lock on entry, drops on exit.
  */
 int
 setrunnable(struct thread *td, int srqflags)
 {
-       int swapin;
-
        THREAD_LOCK_ASSERT(td, MA_OWNED);
        KASSERT(td->td_proc->p_state != PRS_ZOMBIE,
            ("setrunnable: pid %d is a zombie", td->td_proc->p_pid));
 
-       swapin = 0;
        switch (TD_GET_STATE(td)) {
        case TDS_RUNNING:
        case TDS_RUNQ:
+       case TDS_INHIBITED:
+               if ((srqflags & (SRQ_HOLD | SRQ_HOLDTD)) == 0)
+                       thread_unlock(td);
                break;
        case TDS_CAN_RUN:
                KASSERT((td->td_flags & TDF_INMEM) != 0,
@@ -584,25 +582,12 @@ setrunnable(struct thread *td, int srqflags)
                    td, td->td_flags, td->td_inhibitors));
                /* unlocks thread lock according to flags */
                sched_wakeup(td, srqflags);
-               return (0);
-       case TDS_INHIBITED:
-               /*
-                * If we are only inhibited because we are swapped out
-                * arrange to swap in this process.
-                */
-               if (td->td_inhibitors == TDI_SWAPPED &&
-                   (td->td_flags & TDF_SWAPINREQ) == 0) {
-                       td->td_flags |= TDF_SWAPINREQ;
-                       swapin = 1;
-               }
                break;
        default:
                panic("setrunnable: state 0x%x", TD_GET_STATE(td));
        }
-       if ((srqflags & (SRQ_HOLD | SRQ_HOLDTD)) == 0)
-               thread_unlock(td);
 
-       return (swapin);
+       return (0);
 }
 
 /*
diff --git a/sys/kern/sched_4bsd.c b/sys/kern/sched_4bsd.c
index ff1e57746404..6d94cc7f8ed1 100644
--- a/sys/kern/sched_4bsd.c
+++ b/sys/kern/sched_4bsd.c
@@ -998,8 +998,6 @@ sched_sleep(struct thread *td, int pri)
        td_get_sched(td)->ts_slptime = 0;
        if (pri != 0 && PRI_BASE(td->td_pri_class) == PRI_TIMESHARE)
                sched_prio(td, pri);
-       if (TD_IS_SUSPENDED(td) || pri >= PSOCK)
-               td->td_flags |= TDF_CANSWAP;
 }
 
 void
@@ -1137,7 +1135,6 @@ sched_wakeup(struct thread *td, int srqflags)
 
        THREAD_LOCK_ASSERT(td, MA_OWNED);
        ts = td_get_sched(td);
-       td->td_flags &= ~TDF_CANSWAP;
        if (ts->ts_slptime > 1) {
                updatepri(td);
                resetpriority(td);
diff --git a/sys/kern/sched_ule.c b/sys/kern/sched_ule.c
index 502802047cd4..39cb648c2216 100644
--- a/sys/kern/sched_ule.c
+++ b/sys/kern/sched_ule.c
@@ -2334,8 +2334,6 @@ sched_sleep(struct thread *td, int prio)
        THREAD_LOCK_ASSERT(td, MA_OWNED);
 
        td->td_slptick = ticks;
-       if (TD_IS_SUSPENDED(td) || prio >= PSOCK)
-               td->td_flags |= TDF_CANSWAP;
        if (PRI_BASE(td->td_pri_class) != PRI_TIMESHARE)
                return;
        if (static_boost == 1 && prio)
@@ -2358,7 +2356,6 @@ sched_wakeup(struct thread *td, int srqflags)
 
        THREAD_LOCK_ASSERT(td, MA_OWNED);
        ts = td_get_sched(td);
-       td->td_flags &= ~TDF_CANSWAP;
 
        /*
         * If we slept for more than a tick update our interactivity and
diff --git a/sys/kern/tty_info.c b/sys/kern/tty_info.c
index f54fc3a30f5e..638180292f67 100644
--- a/sys/kern/tty_info.c
+++ b/sys/kern/tty_info.c
@@ -369,12 +369,8 @@ tty_info(struct tty *tp)
        kstacks_val = atomic_load_int(&tty_info_kstacks);
        print_kstacks = (kstacks_val != STACK_SBUF_FMT_NONE);
 
-       if (print_kstacks) {
-               if (TD_IS_SWAPPED(td))
-                       sterr = ENOENT;
-               else
-                       sterr = stack_save_td(&stack, td);
-       }
+       if (print_kstacks)
+               sterr = stack_save_td(&stack, td);
 #endif
        thread_unlock(td);
        if (p->p_state == PRS_NEW || p->p_state == PRS_ZOMBIE)
diff --git a/sys/powerpc/powerpc/stack_machdep.c 
b/sys/powerpc/powerpc/stack_machdep.c
index 2d1a45c71c5a..b34d97958cd9 100644
--- a/sys/powerpc/powerpc/stack_machdep.c
+++ b/sys/powerpc/powerpc/stack_machdep.c
@@ -91,8 +91,6 @@ stack_save_td(struct stack *st, struct thread *td)
        vm_offset_t frame;
 
        THREAD_LOCK_ASSERT(td, MA_OWNED);
-       KASSERT(!TD_IS_SWAPPED(td),
-           ("stack_save_td: thread %p is swapped", td));
 
        if (TD_IS_RUNNING(td))
                return (EOPNOTSUPP);
diff --git a/sys/riscv/riscv/stack_machdep.c b/sys/riscv/riscv/stack_machdep.c
index 25ddf6ddfa0b..92d82220a9be 100644
--- a/sys/riscv/riscv/stack_machdep.c
+++ b/sys/riscv/riscv/stack_machdep.c
@@ -65,8 +65,6 @@ stack_save_td(struct stack *st, struct thread *td)
        struct unwind_state frame;
 
        THREAD_LOCK_ASSERT(td, MA_OWNED);
-       KASSERT(!TD_IS_SWAPPED(td),
-           ("stack_save_td: thread %p is swapped", td));
 
        if (TD_IS_RUNNING(td))
                return (EOPNOTSUPP);
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index c492cd10e712..167ac275c920 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -452,7 +452,7 @@ do {                                                        
                \
 #define        TDF_SINTR       0x00000008 /* Sleep is interruptible. */
 #define        TDF_TIMEOUT     0x00000010 /* Timing out during sleep. */
 #define        TDF_IDLETD      0x00000020 /* This is a per-CPU idle thread. */
-#define        TDF_CANSWAP     0x00000040 /* Thread can be swapped. */
+#define        TDF_UNUSED11    0x00000040 /* Available */
 #define        TDF_SIGWAIT     0x00000080 /* Ignore ignored signals */
 #define        TDF_KTH_SUSP    0x00000100 /* kthread is suspended */
 #define        TDF_ALLPROCSUSP 0x00000200 /* suspended by SINGLE_ALLPROC */
@@ -468,7 +468,7 @@ do {                                                        
                \
 #define        TDF_SERESTART   0x00080000 /* ERESTART on stop attempts. */
 #define        TDF_THRWAKEUP   0x00100000 /* Libthr thread must not suspend 
itself. */
 #define        TDF_SEINTR      0x00200000 /* EINTR on stop attempts. */
-#define        TDF_SWAPINREQ   0x00400000 /* Swapin request due to wakeup. */
+#define        TDF_UNUSED12    0x00400000 /* Available */
 #define        TDF_UNUSED6     0x00800000 /* Available */
 #define        TDF_SCHED0      0x01000000 /* Reserved for scheduler private 
use */
 #define        TDF_SCHED1      0x02000000 /* Reserved for scheduler private 
use */
@@ -574,14 +574,12 @@ enum {
  */
 #define        TDI_SUSPENDED   0x0001  /* On suspension queue. */
 #define        TDI_SLEEPING    0x0002  /* Actually asleep! (tricky). */
-#define        TDI_SWAPPED     0x0004  /* Stack not in mem.  Bad juju if run. 
*/
 #define        TDI_LOCK        0x0008  /* Stopped on a lock. */
 #define        TDI_IWAIT       0x0010  /* Awaiting interrupt. */
 
 #define        TD_IS_SLEEPING(td)      ((td)->td_inhibitors & TDI_SLEEPING)
 #define        TD_ON_SLEEPQ(td)        ((td)->td_wchan != NULL)
 #define        TD_IS_SUSPENDED(td)     ((td)->td_inhibitors & TDI_SUSPENDED)
-#define        TD_IS_SWAPPED(td)       ((td)->td_inhibitors & TDI_SWAPPED)
 #define        TD_ON_LOCK(td)          ((td)->td_inhibitors & TDI_LOCK)
 #define        TD_AWAITING_INTR(td)    ((td)->td_inhibitors & TDI_IWAIT)
 #ifdef _KERNEL
@@ -602,7 +600,6 @@ enum {
 #define        KTDSTATE(td)                                                    
\
        (((td)->td_inhibitors & TDI_SLEEPING) != 0 ? "sleep"  :         \
        ((td)->td_inhibitors & TDI_SUSPENDED) != 0 ? "suspended" :      \
-       ((td)->td_inhibitors & TDI_SWAPPED) != 0 ? "swapped" :          \
        ((td)->td_inhibitors & TDI_LOCK) != 0 ? "blocked" :             \
        ((td)->td_inhibitors & TDI_IWAIT) != 0 ? "iwait" : "yielding")
 
@@ -618,14 +615,12 @@ enum {
 } while (0)
 
 #define        TD_SET_SLEEPING(td)     TD_SET_INHIB((td), TDI_SLEEPING)
-#define        TD_SET_SWAPPED(td)      TD_SET_INHIB((td), TDI_SWAPPED)
 #define        TD_SET_LOCK(td)         TD_SET_INHIB((td), TDI_LOCK)
 #define        TD_SET_SUSPENDED(td)    TD_SET_INHIB((td), TDI_SUSPENDED)
 #define        TD_SET_IWAIT(td)        TD_SET_INHIB((td), TDI_IWAIT)
 #define        TD_SET_EXITING(td)      TD_SET_INHIB((td), TDI_EXITING)
 
 #define        TD_CLR_SLEEPING(td)     TD_CLR_INHIB((td), TDI_SLEEPING)
-#define        TD_CLR_SWAPPED(td)      TD_CLR_INHIB((td), TDI_SWAPPED)
 #define        TD_CLR_LOCK(td)         TD_CLR_INHIB((td), TDI_LOCK)
 #define        TD_CLR_SUSPENDED(td)    TD_CLR_INHIB((td), TDI_SUSPENDED)
 #define        TD_CLR_IWAIT(td)        TD_CLR_INHIB((td), TDI_IWAIT)
@@ -816,8 +811,7 @@ struct proc {
                                           shortcuts) */
 #define        P_SUGID         0x00000100      /* Had set id privileges since 
last
                                           exec. */
-#define        P_SYSTEM        0x00000200      /* System proc: no sigs, stats 
or
-                                          swapping. */
+#define        P_SYSTEM        0x00000200      /* System proc: no sigs or 
stats. */
 #define        P_SINGLE_EXIT   0x00000400      /* Threads suspending should 
exit,
                                           not wait. */
 #define        P_TRACED        0x00000800      /* Debugged process being 
traced. */
@@ -842,8 +836,8 @@ struct proc {
 #define        P_INEXEC        0x04000000      /* Process is in execve(). */
 #define        P_STATCHILD     0x08000000      /* Child process stopped or 
exited. */
 #define        P_INMEM         0x10000000      /* Loaded into memory. */
-#define        P_SWAPPINGOUT   0x20000000      /* Process is being swapped 
out. */
-#define        P_SWAPPINGIN    0x40000000      /* Process is being swapped in. 
*/
+#define        P_UNUSED1       0x20000000      /* --available-- */
+#define        P_UNUSED2       0x40000000      /* --available-- */
 #define        P_PPTRACE       0x80000000      /* PT_TRACEME by vforked child. 
*/
 
 #define        P_STOPPED       (P_STOPPED_SIG|P_STOPPED_SINGLE|P_STOPPED_TRACE)
@@ -1038,9 +1032,6 @@ extern pid_t pid_max;
        _p->p_cowgen - _td->td_cowgen;                                  \
 })
 
-/* Check whether a thread is safe to be swapped out. */
-#define        thread_safetoswapout(td)        ((td)->td_flags & TDF_CANSWAP)
-
 /* Control whether or not it is safe for curthread to sleep. */
 #define        THREAD_NO_SLEEPING()            do {                            
\
        curthread->td_no_sleeping++;                                    \
diff --git a/sys/sys/user.h b/sys/sys/user.h
index e76b2a66ae94..96f17bffff8c 100644
--- a/sys/sys/user.h
+++ b/sys/sys/user.h
@@ -613,7 +613,7 @@ struct kinfo_vmobject {
 #define        KKST_MAXLEN     1024
 
 #define        KKST_STATE_STACKOK      0               /* Stack is valid. */
-#define        KKST_STATE_SWAPPED      1               /* Stack swapped out. */
+#define        KKST_STATE_SWAPPED      1               /* Stack swapped out, 
obsolete. */
 #define        KKST_STATE_RUNNING      2               /* Stack ephemeral. */
 
 #if defined(__amd64__) || defined(__i386__)
diff --git a/sys/vm/vm_meter.c b/sys/vm/vm_meter.c
index d255f8e8f358..7348577fc3cb 100644
--- a/sys/vm/vm_meter.c
+++ b/sys/vm/vm_meter.c
@@ -189,9 +189,7 @@ vmtotal(SYSCTL_HANDLER_ARGS)
                                thread_lock(td);
                                switch (TD_GET_STATE(td)) {
                                case TDS_INHIBITED:
-                                       if (TD_IS_SWAPPED(td))
-                                               total.t_sw++;
-                                       else if (TD_IS_SLEEPING(td)) {
+                                       if (TD_IS_SLEEPING(td)) {
                                                if (td->td_priority <= PZERO)
                                                        total.t_dw++;
                                                else
diff --git a/sys/vm/vm_pageout.c b/sys/vm/vm_pageout.c
index e32d27f2300a..e848d68739ca 100644
--- a/sys/vm/vm_pageout.c
+++ b/sys/vm/vm_pageout.c
@@ -1960,8 +1960,7 @@ vm_pageout_oom(int shortage)
                        if (!TD_ON_RUNQ(td) &&
                            !TD_IS_RUNNING(td) &&
                            !TD_IS_SLEEPING(td) &&
-                           !TD_IS_SUSPENDED(td) &&
-                           !TD_IS_SWAPPED(td)) {
+                           !TD_IS_SUSPENDED(td)) {
                                thread_unlock(td);
                                breakout = true;
                                break;
diff --git a/sys/x86/x86/stack_machdep.c b/sys/x86/x86/stack_machdep.c
index 746c560a094b..f1084a1d3b0c 100644
--- a/sys/x86/x86/stack_machdep.c
+++ b/sys/x86/x86/stack_machdep.c
@@ -109,8 +109,6 @@ stack_save_td(struct stack *st, struct thread *td)
        bool done;
 
        THREAD_LOCK_ASSERT(td, MA_OWNED);
-       KASSERT(!TD_IS_SWAPPED(td),
-           ("stack_save_td: thread %p is swapped", td));
        if (TD_IS_RUNNING(td) && td != curthread)
                PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
 

Reply via email to