diff options
author | Jim Cromie <jim.cromie@gmail.com> | 2020-07-19 17:10:55 -0600 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-07-24 17:00:09 +0200 |
commit | 84da83a6ffc0b730f64604d869e0697ad106fd42 (patch) | |
tree | 5d2a35bfb104c02d3ed25640f4346ea0b59de1b5 /lib | |
parent | 14775b04964264189caa4a0862eac05dab8c0502 (diff) | |
download | linux-84da83a6ffc0b730f64604d869e0697ad106fd42.tar.bz2 |
dyndbg: combine flags & mask into a struct, simplify with it
flags & mask are used together everywhere, and are passed around
together between multiple functions; they belong together in a struct,
call that struct flag_settings.
Use struct flag_settings to rework 3 functions:
- ddebug_exec_query - declares query and flag-settings,
calls other 2, passing flags
- ddebug_parse_flags - fills flag_settings and returns
- ddebug_change - test all callsites against query,
modify passing sites.
benefits:
- bit-banging always needs flags & mask, best together.
- simpler function signatures
- 1 less parameter, less stack overhead
no functional changes
Acked-by: <jbaron@akamai.com>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20200719231058.1586423-16-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/dynamic_debug.c | 45 |
1 files changed, 24 insertions, 21 deletions
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index fad6c34c930d..c983049e986d 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -62,6 +62,11 @@ struct ddebug_iter { unsigned int idx; }; +struct flag_settings { + unsigned int flags; + unsigned int mask; +}; + static DEFINE_MUTEX(ddebug_lock); static LIST_HEAD(ddebug_tables); static int verbose; @@ -141,7 +146,7 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg) * logs the changes. Takes ddebug_lock. */ static int ddebug_change(const struct ddebug_query *query, - unsigned int flags, unsigned int mask) + struct flag_settings *modifiers) { int i; struct ddebug_table *dt; @@ -190,14 +195,14 @@ static int ddebug_change(const struct ddebug_query *query, nfound++; - newflags = (dp->flags & mask) | flags; + newflags = (dp->flags & modifiers->mask) | modifiers->flags; if (newflags == dp->flags) continue; #ifdef CONFIG_JUMP_LABEL if (dp->flags & _DPRINTK_FLAGS_PRINT) { - if (!(flags & _DPRINTK_FLAGS_PRINT)) + if (!(modifiers->flags & _DPRINTK_FLAGS_PRINT)) static_branch_disable(&dp->key.dd_key_true); - } else if (flags & _DPRINTK_FLAGS_PRINT) + } else if (modifiers->flags & _DPRINTK_FLAGS_PRINT) static_branch_enable(&dp->key.dd_key_true); #endif dp->flags = newflags; @@ -431,11 +436,9 @@ static int ddebug_parse_query(char *words[], int nwords, * flags fields of matched _ddebug's. Returns 0 on success * or <0 on error. */ -static int ddebug_parse_flags(const char *str, unsigned int *flagsp, - unsigned int *maskp) +static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) { - unsigned flags = 0; - int op = '=', i; + int op, i; switch (*str) { case '+': @@ -452,7 +455,7 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp, for (; *str ; ++str) { for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) { if (*str == opt_array[i].opt_char) { - flags |= opt_array[i].flag; + modifiers->flags |= opt_array[i].flag; break; } } @@ -461,30 +464,30 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp, return -EINVAL; } } - vpr_info("flags=0x%x\n", flags); + vpr_info("flags=0x%x\n", modifiers->flags); - /* calculate final *flagsp, *maskp according to mask and op */ + /* calculate final flags, mask based upon op */ switch (op) { case '=': - *maskp = 0; - *flagsp = flags; + /* modifiers->flags already set */ + modifiers->mask = 0; break; case '+': - *maskp = ~0U; - *flagsp = flags; + modifiers->mask = ~0U; break; case '-': - *maskp = ~flags; - *flagsp = 0; + modifiers->mask = ~modifiers->flags; + modifiers->flags = 0; break; } - vpr_info("*flagsp=0x%x *maskp=0x%x\n", *flagsp, *maskp); + vpr_info("*flagsp=0x%x *maskp=0x%x\n", modifiers->flags, modifiers->mask); + return 0; } static int ddebug_exec_query(char *query_string, const char *modname) { - unsigned int flags = 0, mask = 0; + struct flag_settings modifiers = {}; struct ddebug_query query = {}; #define MAXWORDS 9 int nwords, nfound; @@ -496,7 +499,7 @@ static int ddebug_exec_query(char *query_string, const char *modname) return -EINVAL; } /* check flags 1st (last arg) so query is pairs of spec,val */ - if (ddebug_parse_flags(words[nwords-1], &flags, &mask)) { + if (ddebug_parse_flags(words[nwords-1], &modifiers)) { pr_err("flags parse failed\n"); return -EINVAL; } @@ -505,7 +508,7 @@ static int ddebug_exec_query(char *query_string, const char *modname) return -EINVAL; } /* actually go and implement the change */ - nfound = ddebug_change(&query, flags, mask); + nfound = ddebug_change(&query, &modifiers); vpr_info_dq(&query, nfound ? "applied" : "no-match"); return nfound; |