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| author |   Olof Johansson <olof@lixom.net> | 2013-07-12 10:59:39 -0700 |
|---|---|---|
| committer | Olof Johansson <olof@lixom.net> | 2013-07-12 10:59:39 -0700 |
| commit | f4b96f5e4ff8d86699c851c10245e102809b0331 (patch) | |
| tree | f766102263bed71738431cabb4d4f6f086005cd8 /lib/dump_stack.c | |
| parent | ARM: omap2: add select of TI_PRIV_EDMA (diff) | |
| parent | ARM: OMAP2+: omap2plus_defconfig: Enable appended DTB support (diff) | |
| download | wireguard-linux-f4b96f5e4ff8d86699c851c10245e102809b0331.tar.xz wireguard-linux-f4b96f5e4ff8d86699c851c10245e102809b0331.zip | |
Merge tag 'omap-for-v3.11/fixes-for-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes
Omap fixes and minor defconfig updates that would be good to
get in before -rc1.
* tag 'omap-for-v3.11/fixes-for-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: OMAP2+: omap2plus_defconfig: Enable appended DTB support
ARM: OMAP2+: Enable TI_EDMA in omap2plus_defconfig
ARM: OMAP2+: omap2plus_defconfig: enable DRA752 thermal support by default
ARM: OMAP2+: omap2plus_defconfig: enable TI bandgap driver
ARM: OMAP2+: devices: remove duplicated include from devices.c
ARM: OMAP3: igep0020: Set DSS pins in correct mux mode.
ARM: OMAP2+: N900: enable N900-specific drivers even if device tree is enabled
ARM: OMAP2+: Cocci spatch "ptr_ret.spatch"
ARM: OMAP2+: Remove obsolete Makefile line
ARM: OMAP5: Enable Cortex A15 errata 798181
ARM: scu: provide inline dummy functions when SCU is not present
ARM: OMAP4: sleep: build OMAP4 specific functions only for OMAP4
ARM: OMAP2+: timer: initialize before using oh_name
Signed-off-by: Olof Johansson <olof@lixom.net>
Add/move/change conflicts in arch/arm/mach-omap2/Kconfig resolved.
Diffstat (limited to 'lib/dump_stack.c')
| -rw-r--r-- | lib/dump_stack.c | 47 |
1 files changed, 45 insertions, 2 deletions
diff --git a/lib/dump_stack.c b/lib/dump_stack.c index 53bad099ebd6..c03154173cc7 100644 --- a/lib/dump_stack.c +++ b/lib/dump_stack.c @@ -6,15 +6,58 @@ #include <linux/kernel.h> #include <linux/export.h> #include <linux/sched.h> +#include <linux/smp.h> +#include <linux/atomic.h> + +static void __dump_stack(void) +{ + dump_stack_print_info(KERN_DEFAULT); + show_stack(NULL, NULL); +} /** * dump_stack - dump the current task information and its stack trace * * Architectures can override this implementation by implementing its own. */ +#ifdef CONFIG_SMP +static atomic_t dump_lock = ATOMIC_INIT(-1); + void dump_stack(void) { - dump_stack_print_info(KERN_DEFAULT); - show_stack(NULL, NULL); + int was_locked; + int old; + int cpu; + + /* + * Permit this cpu to perform nested stack dumps while serialising + * against other CPUs + */ + preempt_disable(); + +retry: + cpu = smp_processor_id(); + old = atomic_cmpxchg(&dump_lock, -1, cpu); + if (old == -1) { + was_locked = 0; + } else if (old == cpu) { + was_locked = 1; + } else { + cpu_relax(); + goto retry; + } + + __dump_stack(); + + if (!was_locked) + atomic_set(&dump_lock, -1); + + preempt_enable(); +} +#else +void dump_stack(void) +{ + __dump_stack(); } +#endif EXPORT_SYMBOL(dump_stack); |