Messages in this thread | | | Date | Sun, 11 Jan 2009 00:11:27 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH 08/16] dma-debug: add core checking functions |
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* Joerg Roedel <joerg.roedel@amd.com> wrote:
> +#define err_printk(dev, format, arg...) do { \ > + error_count += 1; \ > + if (show_all_errors || show_num_errors > 0) { \ > + WARN(1, "%s %s: " format, \ > + dev_driver_string(dev), \ > + dev_name(dev) , ## arg); \ > + } \ > + if (!show_all_errors && show_num_errors > 0) \ > + show_num_errors -= 1; \
Note that the arithmetics here is SMP-unsafe: we only hold the hash bucket so if two errors hit at once on two CPUs then the error tracking variables can be accessed at once.
I'd suggest a simple global lock for this error case (taken inside the hash bucket lock), to be on the safe side.
Also, please dont use a macro for this - printk details can be passed in to helper inlines/functions too.
Ingo
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