Re: [LTP] [PATCH v2 2/7] libltpswap: alter get_used_swapfiles api

Cyril Hrubis
2024-01-03T15:30:32Z

Hi!
> +/*
> + * Get the used swapfiles number
> + */
> +int get_used_swapfiles(const char *file, const int lineno);
> +#define GET_USED_SWAPFILES() \
> + get_used_swapfiles(__FILE__, __LINE__)

This has to be prefixed with tst_

Also I wouldn't bother withg the macro and passing down FILE and LINE,
it's going to be called just once in the test setup anyways.

So I would just add:

int tst_count_swaps(void);

> #endif /* __LIBSWAP_H__ */
> diff --git a/libs/libltpswap/libswap.c b/libs/libltpswap/libswap.c
> index 658ecede7..e10a6f5b2 100644
> --- a/libs/libltpswap/libswap.c
> +++ b/libs/libltpswap/libswap.c
> @@ -14,6 +14,8 @@
> #include "tst_kconfig.h"
> #include "tst_safe_stdio.h"
>
> +#define BUFSIZE 1024
> +
> /*
> * Make a swap file
> */
> @@ -109,3 +111,27 @@ unsigned int get_maxswapfiles(void)
>
> return max_swapfile - swp_migration_num - swp_hwpoison_num - swp_device_num - swp_pte_marker_num;
> }
> +
> +/*
> + * Get the used swapfiles number
> + */
> +int get_used_swapfiles(const char *file, const int lineno)
> +{
> + FILE *fp;
> + int used = -1;
> + char buf[BUFSIZE];
> +
> + fp = safe_fopen(file, lineno, NULL, "/proc/swaps", "r");

I suppose that that we may want to check if the file exists and return 0
if it does not, otherwise we will possibly TBROK here if CONFIG_SWAP is
not set. Or do all the tests that call this function have CONFIG_SWAP in
.needs_kconfig?

> + while (fgets(buf, BUFSIZE, fp) != NULL)
> + used++;

We can do this even simpler:

int c;

while ((c = fgetc(f)) != EOF) {
if (c == '\n')
used++;
}

> + fclose(fp);
> +
> + if (used < 0) {
> + tst_brk(TBROK, "can't read /proc/swaps to get used swapfiles resource total "
> + "at %s:%d", file, lineno);
> + }
> +
> + return used;
> +}
> --
> 2.27.0
>
>
> --
> Mailing list info: https://lists.linux.it/listinfo/ltp

--
Cyril Hrubis
chrubis@suse.cz