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author | Joe Perches <joe@perches.com> | 2012-09-13 03:11:29 (GMT) |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-09-17 13:08:30 (GMT) |
commit | 798efc60e4276825df34af0e91ecbe0781237834 (patch) | |
tree | 8ccec7118a7a76f5731fecb8507643c44936eb49 /drivers/base/core.c | |
parent | 8f949b9a7e0bac3a9c3c29dc27c476a87e21db3e (diff) | |
download | linux-798efc60e4276825df34af0e91ecbe0781237834.tar.xz |
dev_dbg/dynamic_debug: Update to use printk_emit, optimize stack
commit c4e00daaa9
("driver-core: extend dev_printk() to pass structured data")
changed __dev_printk and broke dynamic-debug's ability to control the
dynamic prefix of dev_dbg(dev,..).
commit af7f2158fd
("drivers-core: make structured logging play nice with dynamic-debug")
made a minimal correction.
The current dynamic debug code uses up to 3 recursion levels via %pV.
This can consume quite a bit of stack. Directly call printk_emit to
reduce the recursion depth.
These changes include:
dev_dbg:
o Create and use function create_syslog_header to format the syslog
header for printk_emit uses.
o Call create_syslog_header and neaten __dev_printk
o Make __dev_printk static not global
o Remove include header declaration of __dev_printk
o Remove now unused EXPORT_SYMBOL() of __dev_printk
o Whitespace neatening
dynamic_dev_dbg:
o Remove KERN_DEBUG from dynamic_emit_prefix
o Call create_syslog_header and printk_emit
o Whitespace neatening
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base/core.c')
-rw-r--r-- | drivers/base/core.c | 64 |
1 files changed, 34 insertions, 30 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c index 91478bd..d325b9d 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1865,26 +1865,19 @@ void device_shutdown(void) */ #ifdef CONFIG_PRINTK -int __dev_printk(const char *level, const struct device *dev, - struct va_format *vaf) +int create_syslog_header(const struct device *dev, char *hdr, size_t hdrlen) { - char dict[128]; - const char *level_extra = ""; - size_t dictlen = 0; const char *subsys; - - if (!dev) - return printk("%s(NULL device *): %pV", level, vaf); + size_t pos = 0; if (dev->class) subsys = dev->class->name; else if (dev->bus) subsys = dev->bus->name; else - goto skip; + return 0; - dictlen += snprintf(dict + dictlen, sizeof(dict) - dictlen, - "SUBSYSTEM=%s", subsys); + pos += snprintf(hdr + pos, hdrlen - pos, "SUBSYSTEM=%s", subsys); /* * Add device identifier DEVICE=: @@ -1900,32 +1893,41 @@ int __dev_printk(const char *level, const struct device *dev, c = 'b'; else c = 'c'; - dictlen++; - dictlen += snprintf(dict + dictlen, sizeof(dict) - dictlen, - "DEVICE=%c%u:%u", - c, MAJOR(dev->devt), MINOR(dev->devt)); + pos++; + pos += snprintf(hdr + pos, hdrlen - pos, + "DEVICE=%c%u:%u", + c, MAJOR(dev->devt), MINOR(dev->devt)); } else if (strcmp(subsys, "net") == 0) { struct net_device *net = to_net_dev(dev); - dictlen++; - dictlen += snprintf(dict + dictlen, sizeof(dict) - dictlen, - "DEVICE=n%u", net->ifindex); + pos++; + pos += snprintf(hdr + pos, hdrlen - pos, + "DEVICE=n%u", net->ifindex); } else { - dictlen++; - dictlen += snprintf(dict + dictlen, sizeof(dict) - dictlen, - "DEVICE=+%s:%s", subsys, dev_name(dev)); + pos++; + pos += snprintf(hdr + pos, hdrlen - pos, + "DEVICE=+%s:%s", subsys, dev_name(dev)); } -skip: - if (level[2]) - level_extra = &level[2]; /* skip past KERN_SOH "L" */ - return printk_emit(0, level[1] - '0', - dictlen ? dict : NULL, dictlen, - "%s %s: %s%pV", - dev_driver_string(dev), dev_name(dev), - level_extra, vaf); + return pos; +} +EXPORT_SYMBOL(create_syslog_header); + +static int __dev_printk(const char *level, const struct device *dev, + struct va_format *vaf) +{ + char hdr[128]; + size_t hdrlen; + + if (!dev) + return printk("%s(NULL device *): %pV", level, vaf); + + hdrlen = create_syslog_header(dev, hdr, sizeof(hdr)); + + return printk_emit(0, level[1] - '0', hdrlen ? hdr : NULL, hdrlen, + "%s %s: %pV", + dev_driver_string(dev), dev_name(dev), vaf); } -EXPORT_SYMBOL(__dev_printk); int dev_printk(const char *level, const struct device *dev, const char *fmt, ...) @@ -1940,6 +1942,7 @@ int dev_printk(const char *level, const struct device *dev, vaf.va = &args; r = __dev_printk(level, dev, &vaf); + va_end(args); return r; @@ -1959,6 +1962,7 @@ int func(const struct device *dev, const char *fmt, ...) \ vaf.va = &args; \ \ r = __dev_printk(kern_level, dev, &vaf); \ + \ va_end(args); \ \ return r; \ |