Re: [Qemu-devel] Trying to Understand QEMU's Low Level Functionality ...

[Igor Kovalenko]

On 10/24/07, Atoosaah S <address@hidden> wrote:
> I'm using qemu version 0.8.2 on linux.
>
> I'm currently successful in creating the result.txt (with the command: prof
> /intsall_path/qemu gmon.out > result.txt), but the call graph created does
> not show my functions of interest.
>
> For example i'm trying to understand the sequence of calls qemu makes to
> read/write from the disk image. Using print statements i see the function
> ide_read_dma_cb (from hw directory, file ide.c) being called; as well as
> bdrv_read from (qemu root directory, file block.c). The only ide function i
> see in result.txt is ide_init2 and ide_init_ioport, and the only bdrv type
> functions are bdrv_open2 and bdrv_new. But, listing the symbol table via
> "nm" on qemu, does display my functions of interest ( i.e. bdrv_read,
> bdrv_write, ...). I should see these functions in the gprof result since,
> for example, they are executed frequently (during OS bootup, and
> writting/reading to/from a sample large file)
>
> 1. Why am I only seeing specific low level functions in the call graph?
> 2. Is there a more clear way of finding out how (i.e. sequence of calls)
> qemu make to write to the disk image?

Try valgrind instead?
valgrind --tool=callgrind --smc-check=all -v


-- 
Kind regards,
Igor V. Kovalenko