Dear RT Folks,
I'm pleased to announce the 5.4.44-rt27 stable release. You can get this release via the git tree at: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git branch: v5.4-rt Head SHA1: ee8a165804fcf167113319fa659a4a3d1f18e536 Or to build 5.4.44-rt27 directly, the following patches should be applied: http://www.kernel.org/pub/linux/kernel/v5.x/linux-5.4.tar.xz http://www.kernel.org/pub/linux/kernel/v5.x/patch-5.4.44.xz http://www.kernel.org/pub/linux/kernel/projects/rt/5.4/patch-5.4.44-rt27.patch.xz You can also build from 5.4.44-rt26 by applying the incremental patch: http://www.kernel.org/pub/linux/kernel/projects/rt/5.4/incr/patch-5.4.44-rt26-rt27.patch.xz Enjoy, -- Steve Changes from v5.4.44-rt26: --- John Ogness (1): printk: console must not schedule for drivers Kevin Hao (1): mm: slub: Always flush the delayed empty slubs in flush_all() Liwei Song (1): mm: Don't warn about atomic memory allocations during suspend Sebastian Andrzej Siewior (3): fs/dcache: Include swait.h header Revert "rt: Improve the serial console PASS_LIMIT" mm/zswap: Use local lock to protect per-CPU data Steven Rostedt (VMware) (1): Linux 5.4.44-rt27 汪勇10269566 (1): printk: Force a line break on pr_cont(" ") ---- drivers/tty/serial/8250/8250_core.c | 11 +---------- fs/proc/base.c | 1 + kernel/printk/printk.c | 2 ++ localversion-rt | 2 +- mm/slub.c | 11 +++++------ mm/zswap.c | 21 ++++++++++++--------- 6 files changed, 22 insertions(+), 26 deletions(-) --------------------------- diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 809a65f68028..02bfafa8a672 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -55,16 +55,7 @@ static struct uart_driver serial8250_reg; static unsigned int skip_txen_test; /* force skip of txen test at init time */ -/* - * On -rt we can have a more delays, and legitimately - * so - so don't drop work spuriously and spam the - * syslog: - */ -#ifdef CONFIG_PREEMPT_RT -# define PASS_LIMIT 1000000 -#else -# define PASS_LIMIT 512 -#endif +#define PASS_LIMIT 512 #include <asm/serial.h> /* diff --git a/fs/proc/base.c b/fs/proc/base.c index 2dcd8fb3abb5..dc6cfa5de1df 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -95,6 +95,7 @@ #include <linux/sched/stat.h> #include <linux/posix-timers.h> #include <trace/events/oom.h> +#include <linux/swait.h> #include "internal.h" #include "fd.h" diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 2affe95866a4..2beb8eac13d1 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -1902,6 +1902,7 @@ static void cont_add(int ctx, int cpu, u32 caller_id, int facility, int level, // but later continuations can add a newline. if (flags & LOG_NEWLINE) { c->flags |= LOG_NEWLINE; + cont_flush(ctx); } } @@ -2746,6 +2747,7 @@ static int printk_kthread_func(void *data) &len, printk_time); console_lock(); + console_may_schedule = 0; call_console_drivers(master_seq, ext_text, ext_len, text, len, msg->level, msg->facility); if (len > 0 || ext_len > 0) diff --git a/localversion-rt b/localversion-rt index 2e9afd4a0afd..be1e37b64ad0 100644 --- a/localversion-rt +++ b/localversion-rt @@ -1 +1 @@ --rt26 +-rt27 diff --git a/mm/slub.c b/mm/slub.c index 44a602fc8a16..b2809a9ca8f8 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1635,7 +1635,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) enableirqs = true; #ifdef CONFIG_PREEMPT_RT - if (system_state > SYSTEM_BOOTING) + if (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND) enableirqs = true; #endif if (enableirqs) @@ -2382,9 +2382,6 @@ static void flush_all(struct kmem_cache *s) for_each_online_cpu(cpu) { struct slub_free_list *f; - if (!has_cpu_slab(cpu, s)) - continue; - f = &per_cpu(slub_free_list, cpu); raw_spin_lock_irq(&f->lock); list_splice_init(&f->list, &tofree); @@ -2751,7 +2748,8 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s, unsigned long tid; if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP)) - WARN_ON_ONCE(!preemptible() && system_state >= SYSTEM_SCHEDULING); + WARN_ON_ONCE(!preemptible() && + (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND)); s = slab_pre_alloc_hook(s, gfpflags); if (!s) @@ -3216,7 +3214,8 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, int i; if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP)) - WARN_ON_ONCE(!preemptible() && system_state >= SYSTEM_SCHEDULING); + WARN_ON_ONCE(!preemptible() && + (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND)); /* memcg and kmem_cache debug support */ s = slab_pre_alloc_hook(s, flags); diff --git a/mm/zswap.c b/mm/zswap.c index 21d2d3ed3d6d..3c9644b51f3f 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -372,6 +372,8 @@ static struct zswap_entry *zswap_entry_find_get(struct rb_root *root, * per-cpu code **********************************/ static DEFINE_PER_CPU(u8 *, zswap_dstmem); +/* Used for zswap_dstmem and tfm */ +static DEFINE_LOCAL_IRQ_LOCK(zswap_cpu_lock); static int zswap_dstmem_prepare(unsigned int cpu) { @@ -889,10 +891,11 @@ static int zswap_writeback_entry(struct zpool *pool, unsigned long handle) dlen = PAGE_SIZE; src = (u8 *)zhdr + sizeof(struct zswap_header); dst = kmap_atomic(page); - tfm = *get_cpu_ptr(entry->pool->tfm); + local_lock(zswap_cpu_lock); + tfm = *this_cpu_ptr(entry->pool->tfm); ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen); - put_cpu_ptr(entry->pool->tfm); + local_unlock(zswap_cpu_lock); kunmap_atomic(dst); BUG_ON(ret); BUG_ON(dlen != PAGE_SIZE); @@ -981,8 +984,6 @@ static void zswap_fill_page(void *ptr, unsigned long value) memset_l(page, value, PAGE_SIZE / sizeof(unsigned long)); } -/* protect zswap_dstmem from concurrency */ -static DEFINE_LOCAL_IRQ_LOCK(zswap_dstmem_lock); /********************************* * frontswap hooks **********************************/ @@ -1060,7 +1061,8 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset, } /* compress */ - dst = get_locked_var(zswap_dstmem_lock, zswap_dstmem); + local_lock(zswap_cpu_lock); + dst = *this_cpu_ptr(&zswap_dstmem); tfm = *this_cpu_ptr(entry->pool->tfm); src = kmap_atomic(page); ret = crypto_comp_compress(tfm, src, PAGE_SIZE, dst, &dlen); @@ -1088,7 +1090,7 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset, memcpy(buf, &zhdr, hlen); memcpy(buf + hlen, dst, dlen); zpool_unmap_handle(entry->pool->zpool, handle); - put_locked_var(zswap_dstmem_lock, zswap_dstmem); + local_unlock(zswap_cpu_lock); /* populate entry */ entry->offset = offset; @@ -1116,7 +1118,7 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset, return 0; put_dstmem: - put_locked_var(zswap_dstmem_lock, zswap_dstmem); + local_unlock(zswap_cpu_lock); zswap_pool_put(entry->pool); freepage: zswap_entry_cache_free(entry); @@ -1161,9 +1163,10 @@ static int zswap_frontswap_load(unsigned type, pgoff_t offset, if (zpool_evictable(entry->pool->zpool)) src += sizeof(struct zswap_header); dst = kmap_atomic(page); - tfm = *get_cpu_ptr(entry->pool->tfm); + local_lock(zswap_cpu_lock); + tfm = *this_cpu_ptr(entry->pool->tfm); ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen); - put_cpu_ptr(entry->pool->tfm); + local_unlock(zswap_cpu_lock); kunmap_atomic(dst); zpool_unmap_handle(entry->pool->zpool, entry->handle); BUG_ON(ret);
