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author | 2018-12-05 13:16:24 -0500 | |
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committer | 2018-12-05 13:23:38 -0500 | |
commit | 14a4467a0a5eacb2ebbe3aab1b4e25af3519c76a (patch) | |
tree | 541647056606d3e0aa1e06e62d2b40417623f8cb /arch/x86/xen/spinlock.c | |
parent | media: pixfmt-meta-d4xx.rst: Add a license to it (diff) | |
parent | Merge tag 'media/v4.20-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mc... (diff) | |
download | linux-14a4467a0a5eacb2ebbe3aab1b4e25af3519c76a.tar.gz linux-14a4467a0a5eacb2ebbe3aab1b4e25af3519c76a.tar.bz2 linux-14a4467a0a5eacb2ebbe3aab1b4e25af3519c76a.zip |
Merge commit '0072a0c14d5b7cb72c611d396f143f5dcd73ebe2' into patchwork
Merge from Upstream after the latest media fixes branch, because we
need one patch that it is there.
* commit '0072a0c14d5b7cb72c611d396f143f5dcd73ebe2': (1108 commits)
ide: Change to use DEFINE_SHOW_ATTRIBUTE macro
ide: pmac: add of_node_put()
drivers/tty: add missing of_node_put()
drivers/sbus/char: add of_node_put()
sbus: char: add of_node_put()
Linux 4.20-rc5
PCI: Fix incorrect value returned from pcie_get_speed_cap()
MAINTAINERS: Update linux-mips mailing list address
ocfs2: fix potential use after free
mm/khugepaged: fix the xas_create_range() error path
mm/khugepaged: collapse_shmem() do not crash on Compound
mm/khugepaged: collapse_shmem() without freezing new_page
mm/khugepaged: minor reorderings in collapse_shmem()
mm/khugepaged: collapse_shmem() remember to clear holes
mm/khugepaged: fix crashes due to misaccounted holes
mm/khugepaged: collapse_shmem() stop if punched or truncated
mm/huge_memory: fix lockdep complaint on 32-bit i_size_read()
mm/huge_memory: splitting set mapping+index before unfreeze
mm/huge_memory: rename freeze_page() to unmap_page()
initramfs: clean old path before creating a hardlink
...
Diffstat (limited to 'arch/x86/xen/spinlock.c')
-rw-r--r-- | arch/x86/xen/spinlock.c | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index 441c88262169..3776122c87cc 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -3,24 +3,21 @@ * Split spinlock implementation out into its own file, so it can be * compiled in a FTRACE-compatible way. */ -#include <linux/kernel_stat.h> +#include <linux/kernel.h> #include <linux/spinlock.h> -#include <linux/debugfs.h> -#include <linux/log2.h> -#include <linux/gfp.h> #include <linux/slab.h> +#include <linux/atomic.h> #include <asm/paravirt.h> #include <asm/qspinlock.h> -#include <xen/interface/xen.h> #include <xen/events.h> #include "xen-ops.h" -#include "debugfs.h" static DEFINE_PER_CPU(int, lock_kicker_irq) = -1; static DEFINE_PER_CPU(char *, irq_name); +static DEFINE_PER_CPU(atomic_t, xen_qlock_wait_nest); static bool xen_pvspin = true; static void xen_qlock_kick(int cpu) @@ -39,25 +36,25 @@ static void xen_qlock_kick(int cpu) */ static void xen_qlock_wait(u8 *byte, u8 val) { - unsigned long flags; int irq = __this_cpu_read(lock_kicker_irq); + atomic_t *nest_cnt = this_cpu_ptr(&xen_qlock_wait_nest); /* If kicker interrupts not initialized yet, just spin */ if (irq == -1 || in_nmi()) return; - /* Guard against reentry. */ - local_irq_save(flags); + /* Detect reentry. */ + atomic_inc(nest_cnt); - /* If irq pending already clear it. */ - if (xen_test_irq_pending(irq)) { + /* If irq pending already and no nested call clear it. */ + if (atomic_read(nest_cnt) == 1 && xen_test_irq_pending(irq)) { xen_clear_irq_pending(irq); } else if (READ_ONCE(*byte) == val) { /* Block until irq becomes pending (or a spurious wakeup) */ xen_poll_irq(irq); } - local_irq_restore(flags); + atomic_dec(nest_cnt); } static irqreturn_t dummy_handler(int irq, void *dev_id) |